蒲公英属植物繁殖生物学研究
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摘要
蒲公英属(Taraxacum)植物是菊科(Asteraceae)较大属之一,也是菊科舌状花亚科最进化类群之一,全世界约有300多种,2000多个小种。我国有蒲公英70种,1变种,其中东北有11种。蒲公英属植物在药材、食品、饲料等方面具有广泛应用,并具有一定观赏价值。本论文以沈阳农业大学种质资源异位保存圃为研究地点,对东北地区广泛存在的五种蒲公英为试材,对五种蒲公英的花部综合特征及其繁育系统、花粉母细胞减数分裂行为、胚胎学发育规律、传粉机制、生物量分配动态及生殖配置、流式细胞仪检测成熟种子内胚和胚乳细胞的相对倍性、种子萌发特性等进行研究,分析蒲公英属植物有性生殖与无融合生殖的发生机理,评价不同倍性蒲公英的生殖特性,为进一步研究蒲公英属植物的生殖遗传规律和分子机制奠定基础。
主要结果如下：
(1)东北蒲公英为二倍体,花粉母细胞减数正常,花粉离体萌发率高达70%以上。丹东蒲公英和长春蒲公英为异源三倍体；朝鲜蒲公英和斑叶蒲公英为异源四倍体。蒲公英多倍体均由异源染色体组成。多倍体蒲公英花粉母细胞减数分裂过程异常,存在大量落后染色体、染色体桥、染色体断片以及微核等异常现象,导致四分体时期出现含微核的二分体、三分体、四分体以及多分体等异常现象。多倍体蒲公英花粉活性均低于30%。蒲公英属植物均为同时型胞质分裂,四分体排列方式以正四面体型为主,十字交叉型次之。蒲公英属植物成熟花粉为3-细胞型,多倍体蒲公英中发现成熟花粉存在多核的异常现象,这也是导致花粉活性较低的一个主要原因。
(2)花粉管荧光显微镜观察表明,东北蒲公英花粉只有在异花授粉情况下才能萌发,具有严格的自交不亲和性。多倍体蒲公英的花粉也只有在异花授粉的情况下才能在柱头上萌发,但花粉管生长缓慢,并有扭曲和断裂的异常现象,在未达到胚珠前花粉管就已经消亡。研究结果表明,无融合生殖的蒲公英,其无融合生殖胚和胚乳的发育不依赖于受精。
(3)蒲公英属植物花药4室,药壁发育为简化型,由表皮、药室内壁和绒毡层组成。除朝鲜蒲公英为腺性绒毡层外,其它四种蒲公英均为变形绒毡层。蒲公英为倒生胚珠,单珠皮,薄珠心。有性生殖蒲公英的大孢子母细胞经减数分裂形成线型(或T形)四分体,珠孔端3个大孢子退化,合点端的1个发育成功能大孢子,胚囊发育为蓼型。无融合生殖的蒲公英,大孢子经有丝分裂形成二分体后,珠孔端退化,合子端大孢子继续发育功能性大孢子,并形成单核胚囊,发育过程与东北蒲公英一致,直至形成7细胞8核成熟胚囊,并继续发育,卵细胞形成胚,中央细胞形成胚乳,并在花序开放之前形成原胚。因此授粉对无融合生殖蒲公英的发育无影响。
(4)人工去雄套袋实验表明东北蒲公英为专性异交,长春蒲公英和丹东蒲公英为专性无融合,朝鲜蒲公英和斑叶蒲公英为兼性无融合生殖。流式细胞仪对蒲公英种子进行检测,以确定胚和胚乳的倍性水平。东北蒲公英种子的流式细胞仪检测出2个峰,其倍性之比为2C：3C,表明东北蒲公英发生双受精过程,二倍体胚由受精卵(2n)发育而来,三倍体胚乳由中央细胞和精细胞受精形成。丹东蒲公英种子检测出两个峰,峰值之比为1：2,这一结果无法用双受精理论来解释,表明丹东蒲公英发生无融合生殖,种子由未减数卵细胞(2n)以及中央细胞(4n)发育而来。结果表明胚由未减数卵细胞自发分裂(2C)形成,胚乳由两个未受精极核(融合)自发分裂形成(4C),确定丹东蒲公英为专性无融合生殖类型。朝鲜蒲公英种子检测出3个峰,三峰之比为2C：3C：4C。二倍体峰为胚细胞倍性水平,三倍体峰和四倍体峰为胚乳细胞倍性水平。说明朝鲜蒲公英种子形成存在有性生殖以及无融合生殖,结果表明朝鲜蒲公英属于兼性无融合生殖。综上,得出二倍体蒲公英为专性异交、三倍体为专性无融合以及四倍体为兼性无融合的结论。
(5)蒲公英属植物访花昆虫种类较多,以膜翅目、鳞翅目、双翅目昆虫居多,属于泛化昆虫类型。主要访花昆虫有意大利蜂(Apis mellifera L.)、角马蜂(Apis melliferaL.)食蚜蝇以及蛱蝶等。昆虫访花活动受天气影响较大,传粉者访花行为受天气影响比大,晴天访花者数量多,雨天或阴天访花者数量少。每天访花高峰也不一致,受温度影响较大,5月初,13：00左右气温最适宜,此时有最强的活动高峰,随着天气变暖,活动高峰也不断提前,中旬,11：00左右就形成明显活动高峰。同一天的不同时间,访花者的访花频率差异较大。
(6)经过授粉处理的蒲公英种子比未授粉处理的种子发芽率高40%,授粉与否产生不同的萌发类型：授粉种子属于爆发型机会主义萌发策略,而未授粉种子属于低萌型谨慎萌发策略。缺少冠毛种子的发芽率比正常种子(有冠毛)低16%,并需要更多时间来进行萌发。浸种时间长短对发芽率影响不同,浸种12h种子萌发率最高,超过48h,发芽率、发芽势均降低。而对未授粉处理的种子,浸种却有促进作用。斑叶蒲公英种子在高温(>30℃)及低温(<5℃)情况下,种子萌发均受到明显抑制,萌发温度在10～20℃之间,种子具最大萌发率60%以上。
(7)具有无融合生殖的雌雄同花植物中,减少雄性功能的资源分配具有重要意义。然而,在很多无融合生殖物种中经常可以观察到产生大量花粉的现象。无融合生殖长春蒲公英发现雄性不育系,并对可育系与不育系进行比较研究。发现雄性不育现象可稳定遗传。雄性不育系比可育系产生更多头状花序,更重的种子,这表明产生花粉的资源能够重新分配到产生种子的过程中。雄性不育的无融合生殖蒲公英在自然界中还是很少见的。对不育系和可育系种子萌发特性研究表明,二者萌发特性比较相似,在高温或低温条件下均会受到抑制,不育系比可育系种子具有更高萌发率。
(8)丹东蒲公英存在雌全同株现象。丹东蒲公英均具有形态二型性,即雌花无花粉的红色花药以及两性花的黄色花药。丹东蒲公英雌花两性花分布具位置效应,中央为雌性花,外围为两性花,这与其他菊科植物报道的雌全同株现象相反。观察结果对提高生殖系统的认识、性别二型性和性比例位置效应的进化模式具有重要意义。营养条件不足会导致丹东蒲公英产生更多雌花,表明丹东蒲公英可通过小花形态的可塑性来适应不同的营养条件。雌全同株植物的性分配比例可能比其它繁育系统要复杂的多,这对于验证以及重新定义性分配理论具有重要意义。
(9)蒲公英属植物存在一种特殊的花粉母细胞形成机制----核内染色体复制以及分离现象。这是一种高效的花粉母细胞形成机制,但对于其发生的机制以及调控机制,还缺乏深入的研究。核内染色体复制以及分离机制的调控研究对于多倍体的形成以及提高经济器官的效益具有重要作用。
Taraxacum (Asteraceae), which about70species have been identified in China. According to the statistic,11species of Taraxacum distributed in Northeast China. Taraxacum is used to treat various ailments, such as dyspepsia, spleen and liver problems, heartburn, hepatitis, and anorexia. In traditional Chinese medicine, the dry whole herbage of the dandelion has been used for centuries to cure the common cold, reduce swelling, and facilitate urination. The research location in Ex-situ Conservation, where in shenyang agricultural university. Five Taraxacum species, T. ohwianum Kitag. T. antungense Kitag. T.junpeianum. T. coreanum Nakai. T. variegatum Kitag. were collected from Northeast China In this paper, we studied the flowers syndrome, breeding systems, pollen mother cell meiosis behavior, embryology, pollination mechanism, the dynamic and reproductive allocation of biomass distribution, ploidy level and seed germination characteristics of these species. The main conclusions were as follow:
(1) The number of chromosomes in dandelions were calculated by root tip squashing method. The ploidy level was analyzed by karyotyping. Results showed that the number of chromosomes in T. ohwianum was16with satellites. The pollen mother cell(PMC) meiotic was normal in T. ohwianum, The pollen germination rate in vitro was above70%; the number of chromosomes in T. antungense and T. junpeianum was24, which were allotriploid.; the number of chromosomes in T.coreanum and T. variegatum was32, which were allotetraploid. while abnormal meiosis of PMCs were common in polyploidy dandelions. We observed some abnormal events including lagged chromosomes, chromosome bridge and fragment. At tetrad stage, dyad, triad, tetrad with micronucleus and polyad appeares. The meiosis in Taraxacum undergoes simultaneous cytokinesis, and tetrads were tetrahedral,decussate was lesser. Polyploidy pollen activity were lower than30%. Mature pollen grain was3-cell type, existed abnormal generative cell, abnormal pollen mother cell meiosis and unusual development of generative nucleus were the main reasons for pollen abortion of polyploidy dandelion.
(2)Fluorescence microscope observation showed that the pollen of T. ohwianum can germination only under the condition of cross-pollination, which mean strict self-incompatibility. Polyploidy pollen can also germination on the stigma by the cross-pollination, but the pollen tubes grow slowly, and observed anomalies deformation and fracture of pollen tube before reaching ovule. The results showed that apomixis embryo and endosperm could form autonomously without fertilization.
(3) Anther wall includes four layer. The development of anther wall is primitive type which is composed of epidermis, endothecium and tapetum.apetum cell in T. coreanum is Glandular tapetum, the others apetum cell is of amoeboid tapetum. The megaspore mother cells are developed directly by a hypodermal archesporical cell. Which undergoes meitotic division and forms a linear tetrad. And the megaspore near the chalaza continued to develop into a functional megaspore that would develop into a mononucleate embryo sac, whereas the other three megaspores near the micropyle gradually degenerated. The development of embryo sacs belonged to polygonum type. Apomixis embryo sac megaspore formated dyad, one degradation, the other one which undergoes three tmies mitosis and develops into a mature embryo sac with7cells and7nucle, then egg Continue to develop to forme proembryo, central cell autonomous development later, and the formation of the endosperm, which belongs to the cellular type. Egg formed proembryo befor the Inflorescence open,So pollination or not can not influence the development of apomixis dandelion.
(4) The aim was to develop a simple and efficient screening method that identifies simultaneously different reproductive pathways based on the proportional DNA content of embryo and endosperm nuclei, notwithstanding the real ploidy level. Seed samples of three species were investigated by flow cytometry to reveal the pathway of reproduction. Three different pathways of seed formation could be reconstructed considering whether the female gametes were reduced or unreduced, the embryos arose via the zygotic or parthenogenetic route and the endosperm via the pseudogamous or autonomous route. Flow cytometry showed that the T. ohwianum, T. antungense and T. coreanum ratio of seed cell ploidy level are2c:3c,2c:4c and2c:3c:4c respectively, determine Their reproduction modes were sexual, obligate apomixis and facultative apomixis. The screen of mature seeds by flow cytometry yielded more information about the reproductive behavior of individual plants than any other available test. In conclusion, diploid T. ohwianum for obligate outcrossing, triploid T. antungense for obligate apomixis and tetraploid T. coreanum as apomixis reproductive type.
(5) Several kinds of insects, like hymenoptera, lepidoptera, diptera classified as pollination insects for Taraxacum, so Taraxacum belonging to the generalization pollination. the Main pollination insects were Apis mellifera l,and Apis mellifera1., hoverfly and butterfly, etc. Insect pollination activity and pollination behavior were affected by the weather, the number of insects for visit the flower was higher in sunny day than in rainy or cloudy day, the visit insects. The visit flower peak were different by photoperiod and greatly influenced by temperature.at the beginning of may, around13:00had the strongest activity peak, temperature was the most appropriate.with the warming of weather, peak activity ahead constantly too, in the middle May, at about11:00to form obvious peak activity. On the different time of the same day, pollination frequency was differnet.
(6) In order to understand the seed germination characteristics, we take apomixes T. variegatum (tetraploid) as materials, Surveyed the effect of seed germination by pollination, pappus, seed soaking and temperature. Results indicate that pollination or not has significantly influence on seed germination potential and germination rate. The germination percentage of pollination processing seeds is40%higher than processing without pollination. These two processing (with or without pollination) own different germination strategies:pollination seeds belongs to the'opportunism'germination strategies of rapid germination, but unpollination seeds belongs to'bet hedging'germination strategies of low germination. The germination for seeds lacking a pappus is16%lower than control seeds (with an intact pappus) and that the seeds lacking a pappus require more time to germinate. seed soaking has different effect on germination rate, seed soaking12h has the highest germination rate, more than48h, germination rate, germination potential are both reduced. But for unpollination processing seed, seed soaking can promoting germination. Seed germination of T. variegatum were suppressed at low temperatures(<5℃) and high temperatures(>30℃),10-20℃is the optimum temperature, and has the highest seed germination(>60%).
(7) Male reproductive output has been shown to constitute a substantial cost for many organisms. In parthenogenetic hermaphrodites, selection is therefore expected to reduce the allocation of resources to male reproductive output. However, sustained production of pollen has been observed in numerous asexual hermaphrodites. We studied the widespread production of pollen by triploid asexual dandelions, Taraxacum junpeianum, comparing with rare male sterile individuals with pollen producing asexuals. We found that individuals can show plasticity in the production of pollen, but that it is nevertheless possible to distinguish between male sterile asexuals and male fertile asexuals. Male sterile lineages did not produce more seeds per flower head, heavier seeds or seeds that were more viable. However, male sterile plants did produce more seed heads and hence more seeds than pollen producing ones, indicating that they were able to reallocate resources toward seed production. Considering the difference in seed production, it remains puzzling that not more asexual dandelions are male sterile. Germination characteristics of infertility and sterility of T. junpeianum have been studied at different temperatures. Results from seed-germination experiments indicated that temperature of final percentage germination was qualitatively similar for both Infertility and sterility-germination was suppressed at high and low temperatures.
(8) Gynomonoecy is the sexual system in which individual plants bear both female and bisexual flowers. Little attention has been paid to the adaptive significance of this sexual system, which is particularly prevalent in the Asteraceae. Nevertheless, the sexual system of some dandelions currently remains vaguely characterized as having "bisexual and female flowers." The present study investigates the significance of female flowers in Taraxacum antungense Kitage. It's confirmed that T. antungense is gynomonoecy in field and greenhouse. In addition, sexual dimorphism is found in T. antungense, namely a red syngenesious stamen in female compared to a yellow one in bisexual flowers. A position effect on floral sex was presented in T. antungense. At the inflorescence level, central florets were predominantly female while lateral florets were mainly bisexual, which were opposite to other reports of gynomonoecious in Asteraceae. The observation can improve our knowledge of sexual systems in plants and document relevant evolutionary patterns in sexual dimorphism and position effect of floral sex. Nutrient stress produced fewer bisexual flowers and a higher ratio of female flowers in dandelion capitulums. T. antungense has a phenotypically plastic in floret morphologic. While the floral-sex ratio responses of gynomonoecious plants may be more complicated than other breeding systems of plants, and they offer the potential to test and refine the already rich body of sex-allocation theory.
(9) To obtain dynamic information on endoreplication as well as a division of the pollen mother cells (PMC) in apomicts T. antungense, the entire course of pollen development was observed by the clearing-staining-squash method. Endoreduplication was observed before the PMC. The PMC was formed after endoreduplicational division. The sporogenous cell, which owns24chromosomes and chromosomal DNA replication without intervening mitosis. If the chromosomal replicates successively, the ploidy level would increase exponentially. In this process, the volume of cell increases gradually till the ceasing of chromosomal replication. Consequently, after the division of endoreduplication cell, chromosome number of the PMC becomes normal. There are three kinds of divisions:chromosome division, nuclei division and mix division, meanwhile those processes can produce different sizes of cells. During this period, what we observed are lagging chromosomes and unequal size cells, which suggest that the pollen sterility is so low. The meaning of the occurrence of endoreduplication process and its regulation mechanism need to be further researches.
主要结果如下：
(1)东北蒲公英为二倍体,花粉母细胞减数正常,花粉离体萌发率高达70%以上。丹东蒲公英和长春蒲公英为异源三倍体；朝鲜蒲公英和斑叶蒲公英为异源四倍体。蒲公英多倍体均由异源染色体组成。多倍体蒲公英花粉母细胞减数分裂过程异常,存在大量落后染色体、染色体桥、染色体断片以及微核等异常现象,导致四分体时期出现含微核的二分体、三分体、四分体以及多分体等异常现象。多倍体蒲公英花粉活性均低于30%。蒲公英属植物均为同时型胞质分裂,四分体排列方式以正四面体型为主,十字交叉型次之。蒲公英属植物成熟花粉为3-细胞型,多倍体蒲公英中发现成熟花粉存在多核的异常现象,这也是导致花粉活性较低的一个主要原因。
(2)花粉管荧光显微镜观察表明,东北蒲公英花粉只有在异花授粉情况下才能萌发,具有严格的自交不亲和性。多倍体蒲公英的花粉也只有在异花授粉的情况下才能在柱头上萌发,但花粉管生长缓慢,并有扭曲和断裂的异常现象,在未达到胚珠前花粉管就已经消亡。研究结果表明,无融合生殖的蒲公英,其无融合生殖胚和胚乳的发育不依赖于受精。
(3)蒲公英属植物花药4室,药壁发育为简化型,由表皮、药室内壁和绒毡层组成。除朝鲜蒲公英为腺性绒毡层外,其它四种蒲公英均为变形绒毡层。蒲公英为倒生胚珠,单珠皮,薄珠心。有性生殖蒲公英的大孢子母细胞经减数分裂形成线型(或T形)四分体,珠孔端3个大孢子退化,合点端的1个发育成功能大孢子,胚囊发育为蓼型。无融合生殖的蒲公英,大孢子经有丝分裂形成二分体后,珠孔端退化,合子端大孢子继续发育功能性大孢子,并形成单核胚囊,发育过程与东北蒲公英一致,直至形成7细胞8核成熟胚囊,并继续发育,卵细胞形成胚,中央细胞形成胚乳,并在花序开放之前形成原胚。因此授粉对无融合生殖蒲公英的发育无影响。
(4)人工去雄套袋实验表明东北蒲公英为专性异交,长春蒲公英和丹东蒲公英为专性无融合,朝鲜蒲公英和斑叶蒲公英为兼性无融合生殖。流式细胞仪对蒲公英种子进行检测,以确定胚和胚乳的倍性水平。东北蒲公英种子的流式细胞仪检测出2个峰,其倍性之比为2C：3C,表明东北蒲公英发生双受精过程,二倍体胚由受精卵(2n)发育而来,三倍体胚乳由中央细胞和精细胞受精形成。丹东蒲公英种子检测出两个峰,峰值之比为1：2,这一结果无法用双受精理论来解释,表明丹东蒲公英发生无融合生殖,种子由未减数卵细胞(2n)以及中央细胞(4n)发育而来。结果表明胚由未减数卵细胞自发分裂(2C)形成,胚乳由两个未受精极核(融合)自发分裂形成(4C),确定丹东蒲公英为专性无融合生殖类型。朝鲜蒲公英种子检测出3个峰,三峰之比为2C：3C：4C。二倍体峰为胚细胞倍性水平,三倍体峰和四倍体峰为胚乳细胞倍性水平。说明朝鲜蒲公英种子形成存在有性生殖以及无融合生殖,结果表明朝鲜蒲公英属于兼性无融合生殖。综上,得出二倍体蒲公英为专性异交、三倍体为专性无融合以及四倍体为兼性无融合的结论。
(5)蒲公英属植物访花昆虫种类较多,以膜翅目、鳞翅目、双翅目昆虫居多,属于泛化昆虫类型。主要访花昆虫有意大利蜂(Apis mellifera L.)、角马蜂(Apis melliferaL.)食蚜蝇以及蛱蝶等。昆虫访花活动受天气影响较大,传粉者访花行为受天气影响比大,晴天访花者数量多,雨天或阴天访花者数量少。每天访花高峰也不一致,受温度影响较大,5月初,13：00左右气温最适宜,此时有最强的活动高峰,随着天气变暖,活动高峰也不断提前,中旬,11：00左右就形成明显活动高峰。同一天的不同时间,访花者的访花频率差异较大。
(6)经过授粉处理的蒲公英种子比未授粉处理的种子发芽率高40%,授粉与否产生不同的萌发类型：授粉种子属于爆发型机会主义萌发策略,而未授粉种子属于低萌型谨慎萌发策略。缺少冠毛种子的发芽率比正常种子(有冠毛)低16%,并需要更多时间来进行萌发。浸种时间长短对发芽率影响不同,浸种12h种子萌发率最高,超过48h,发芽率、发芽势均降低。而对未授粉处理的种子,浸种却有促进作用。斑叶蒲公英种子在高温(>30℃)及低温(<5℃)情况下,种子萌发均受到明显抑制,萌发温度在10～20℃之间,种子具最大萌发率60%以上。
(7)具有无融合生殖的雌雄同花植物中,减少雄性功能的资源分配具有重要意义。然而,在很多无融合生殖物种中经常可以观察到产生大量花粉的现象。无融合生殖长春蒲公英发现雄性不育系,并对可育系与不育系进行比较研究。发现雄性不育现象可稳定遗传。雄性不育系比可育系产生更多头状花序,更重的种子,这表明产生花粉的资源能够重新分配到产生种子的过程中。雄性不育的无融合生殖蒲公英在自然界中还是很少见的。对不育系和可育系种子萌发特性研究表明,二者萌发特性比较相似,在高温或低温条件下均会受到抑制,不育系比可育系种子具有更高萌发率。
(8)丹东蒲公英存在雌全同株现象。丹东蒲公英均具有形态二型性,即雌花无花粉的红色花药以及两性花的黄色花药。丹东蒲公英雌花两性花分布具位置效应,中央为雌性花,外围为两性花,这与其他菊科植物报道的雌全同株现象相反。观察结果对提高生殖系统的认识、性别二型性和性比例位置效应的进化模式具有重要意义。营养条件不足会导致丹东蒲公英产生更多雌花,表明丹东蒲公英可通过小花形态的可塑性来适应不同的营养条件。雌全同株植物的性分配比例可能比其它繁育系统要复杂的多,这对于验证以及重新定义性分配理论具有重要意义。
(9)蒲公英属植物存在一种特殊的花粉母细胞形成机制----核内染色体复制以及分离现象。这是一种高效的花粉母细胞形成机制,但对于其发生的机制以及调控机制,还缺乏深入的研究。核内染色体复制以及分离机制的调控研究对于多倍体的形成以及提高经济器官的效益具有重要作用。
Taraxacum (Asteraceae), which about70species have been identified in China. According to the statistic,11species of Taraxacum distributed in Northeast China. Taraxacum is used to treat various ailments, such as dyspepsia, spleen and liver problems, heartburn, hepatitis, and anorexia. In traditional Chinese medicine, the dry whole herbage of the dandelion has been used for centuries to cure the common cold, reduce swelling, and facilitate urination. The research location in Ex-situ Conservation, where in shenyang agricultural university. Five Taraxacum species, T. ohwianum Kitag. T. antungense Kitag. T.junpeianum. T. coreanum Nakai. T. variegatum Kitag. were collected from Northeast China In this paper, we studied the flowers syndrome, breeding systems, pollen mother cell meiosis behavior, embryology, pollination mechanism, the dynamic and reproductive allocation of biomass distribution, ploidy level and seed germination characteristics of these species. The main conclusions were as follow:
(1) The number of chromosomes in dandelions were calculated by root tip squashing method. The ploidy level was analyzed by karyotyping. Results showed that the number of chromosomes in T. ohwianum was16with satellites. The pollen mother cell(PMC) meiotic was normal in T. ohwianum, The pollen germination rate in vitro was above70%; the number of chromosomes in T. antungense and T. junpeianum was24, which were allotriploid.; the number of chromosomes in T.coreanum and T. variegatum was32, which were allotetraploid. while abnormal meiosis of PMCs were common in polyploidy dandelions. We observed some abnormal events including lagged chromosomes, chromosome bridge and fragment. At tetrad stage, dyad, triad, tetrad with micronucleus and polyad appeares. The meiosis in Taraxacum undergoes simultaneous cytokinesis, and tetrads were tetrahedral,decussate was lesser. Polyploidy pollen activity were lower than30%. Mature pollen grain was3-cell type, existed abnormal generative cell, abnormal pollen mother cell meiosis and unusual development of generative nucleus were the main reasons for pollen abortion of polyploidy dandelion.
(2)Fluorescence microscope observation showed that the pollen of T. ohwianum can germination only under the condition of cross-pollination, which mean strict self-incompatibility. Polyploidy pollen can also germination on the stigma by the cross-pollination, but the pollen tubes grow slowly, and observed anomalies deformation and fracture of pollen tube before reaching ovule. The results showed that apomixis embryo and endosperm could form autonomously without fertilization.
(3) Anther wall includes four layer. The development of anther wall is primitive type which is composed of epidermis, endothecium and tapetum.apetum cell in T. coreanum is Glandular tapetum, the others apetum cell is of amoeboid tapetum. The megaspore mother cells are developed directly by a hypodermal archesporical cell. Which undergoes meitotic division and forms a linear tetrad. And the megaspore near the chalaza continued to develop into a functional megaspore that would develop into a mononucleate embryo sac, whereas the other three megaspores near the micropyle gradually degenerated. The development of embryo sacs belonged to polygonum type. Apomixis embryo sac megaspore formated dyad, one degradation, the other one which undergoes three tmies mitosis and develops into a mature embryo sac with7cells and7nucle, then egg Continue to develop to forme proembryo, central cell autonomous development later, and the formation of the endosperm, which belongs to the cellular type. Egg formed proembryo befor the Inflorescence open,So pollination or not can not influence the development of apomixis dandelion.
(4) The aim was to develop a simple and efficient screening method that identifies simultaneously different reproductive pathways based on the proportional DNA content of embryo and endosperm nuclei, notwithstanding the real ploidy level. Seed samples of three species were investigated by flow cytometry to reveal the pathway of reproduction. Three different pathways of seed formation could be reconstructed considering whether the female gametes were reduced or unreduced, the embryos arose via the zygotic or parthenogenetic route and the endosperm via the pseudogamous or autonomous route. Flow cytometry showed that the T. ohwianum, T. antungense and T. coreanum ratio of seed cell ploidy level are2c:3c,2c:4c and2c:3c:4c respectively, determine Their reproduction modes were sexual, obligate apomixis and facultative apomixis. The screen of mature seeds by flow cytometry yielded more information about the reproductive behavior of individual plants than any other available test. In conclusion, diploid T. ohwianum for obligate outcrossing, triploid T. antungense for obligate apomixis and tetraploid T. coreanum as apomixis reproductive type.
(5) Several kinds of insects, like hymenoptera, lepidoptera, diptera classified as pollination insects for Taraxacum, so Taraxacum belonging to the generalization pollination. the Main pollination insects were Apis mellifera l,and Apis mellifera1., hoverfly and butterfly, etc. Insect pollination activity and pollination behavior were affected by the weather, the number of insects for visit the flower was higher in sunny day than in rainy or cloudy day, the visit insects. The visit flower peak were different by photoperiod and greatly influenced by temperature.at the beginning of may, around13:00had the strongest activity peak, temperature was the most appropriate.with the warming of weather, peak activity ahead constantly too, in the middle May, at about11:00to form obvious peak activity. On the different time of the same day, pollination frequency was differnet.
(6) In order to understand the seed germination characteristics, we take apomixes T. variegatum (tetraploid) as materials, Surveyed the effect of seed germination by pollination, pappus, seed soaking and temperature. Results indicate that pollination or not has significantly influence on seed germination potential and germination rate. The germination percentage of pollination processing seeds is40%higher than processing without pollination. These two processing (with or without pollination) own different germination strategies:pollination seeds belongs to the'opportunism'germination strategies of rapid germination, but unpollination seeds belongs to'bet hedging'germination strategies of low germination. The germination for seeds lacking a pappus is16%lower than control seeds (with an intact pappus) and that the seeds lacking a pappus require more time to germinate. seed soaking has different effect on germination rate, seed soaking12h has the highest germination rate, more than48h, germination rate, germination potential are both reduced. But for unpollination processing seed, seed soaking can promoting germination. Seed germination of T. variegatum were suppressed at low temperatures(<5℃) and high temperatures(>30℃),10-20℃is the optimum temperature, and has the highest seed germination(>60%).
(7) Male reproductive output has been shown to constitute a substantial cost for many organisms. In parthenogenetic hermaphrodites, selection is therefore expected to reduce the allocation of resources to male reproductive output. However, sustained production of pollen has been observed in numerous asexual hermaphrodites. We studied the widespread production of pollen by triploid asexual dandelions, Taraxacum junpeianum, comparing with rare male sterile individuals with pollen producing asexuals. We found that individuals can show plasticity in the production of pollen, but that it is nevertheless possible to distinguish between male sterile asexuals and male fertile asexuals. Male sterile lineages did not produce more seeds per flower head, heavier seeds or seeds that were more viable. However, male sterile plants did produce more seed heads and hence more seeds than pollen producing ones, indicating that they were able to reallocate resources toward seed production. Considering the difference in seed production, it remains puzzling that not more asexual dandelions are male sterile. Germination characteristics of infertility and sterility of T. junpeianum have been studied at different temperatures. Results from seed-germination experiments indicated that temperature of final percentage germination was qualitatively similar for both Infertility and sterility-germination was suppressed at high and low temperatures.
(8) Gynomonoecy is the sexual system in which individual plants bear both female and bisexual flowers. Little attention has been paid to the adaptive significance of this sexual system, which is particularly prevalent in the Asteraceae. Nevertheless, the sexual system of some dandelions currently remains vaguely characterized as having "bisexual and female flowers." The present study investigates the significance of female flowers in Taraxacum antungense Kitage. It's confirmed that T. antungense is gynomonoecy in field and greenhouse. In addition, sexual dimorphism is found in T. antungense, namely a red syngenesious stamen in female compared to a yellow one in bisexual flowers. A position effect on floral sex was presented in T. antungense. At the inflorescence level, central florets were predominantly female while lateral florets were mainly bisexual, which were opposite to other reports of gynomonoecious in Asteraceae. The observation can improve our knowledge of sexual systems in plants and document relevant evolutionary patterns in sexual dimorphism and position effect of floral sex. Nutrient stress produced fewer bisexual flowers and a higher ratio of female flowers in dandelion capitulums. T. antungense has a phenotypically plastic in floret morphologic. While the floral-sex ratio responses of gynomonoecious plants may be more complicated than other breeding systems of plants, and they offer the potential to test and refine the already rich body of sex-allocation theory.
(9) To obtain dynamic information on endoreplication as well as a division of the pollen mother cells (PMC) in apomicts T. antungense, the entire course of pollen development was observed by the clearing-staining-squash method. Endoreduplication was observed before the PMC. The PMC was formed after endoreduplicational division. The sporogenous cell, which owns24chromosomes and chromosomal DNA replication without intervening mitosis. If the chromosomal replicates successively, the ploidy level would increase exponentially. In this process, the volume of cell increases gradually till the ceasing of chromosomal replication. Consequently, after the division of endoreduplication cell, chromosome number of the PMC becomes normal. There are three kinds of divisions:chromosome division, nuclei division and mix division, meanwhile those processes can produce different sizes of cells. During this period, what we observed are lagging chromosomes and unequal size cells, which suggest that the pollen sterility is so low. The meaning of the occurrence of endoreduplication process and its regulation mechanism need to be further researches.
引文
1. 蔡雪,母锡金,关雪莲.1998.花椒大孢子发生和雌配子体发育及退化[J].应用基础与工程科学学报,Vol.6(3)：261-264.
2. 陈香,胡雪华,肖宜安,等.紫茉莉的花部综合特征与繁育系统[J].生态学杂志,2008,27(10)：1653～1658.
3. 陈勇,李宏庆,马炜梁2001..雀榕及其传粉昆虫传粉生态研究[J].生态学报,Vol.21(10)：1570-1574.
4. 董宽虎,米佳.2006.白羊草种群繁殖的数量特征.草地学报,14(3)：210-213.
5. 杜国祯.1994.不同温度梯度下亚高寒草甸常见物种的萌发特性研究[J].兰州大学学报(自然科学版),30：112-116.
6. 庚晓红,罗毅波,董鸣.2008.春兰(兰科)传粉生物学的研究[J].植物分类学报,Vol.46(2)：163-174.
7. 龚燕兵黄双全.2007.传粉昆虫行为的研究方法探讨[J].生物多样性,15(6)：576-583.
8. 郭友好.传粉生物学与植物进化.见：陈家宽,杨继主编,植物进化生物学[M].武汉：武汉大学出版社,1994.232-280.
9. 何维明,钟章成.1997.植物繁殖的概念及其研究内容[J].生态学杂志,14(6)：1-3
10. 何亚平,刘建全.2003.植物繁育系统研究的最新进展和评述.植物生态学报,27(2)：151-163
11. 何亚平,刘建全.2004.青藏高原高山植物麻花芜的传粉生态学研究[J].生态学报,Vol.24(2)：215-220.
12. 贺海霞.2006.濒危植物独叶草(毛莨科)的传粉生物学及繁育系统研究[D].西安：陕西师范大学出版社,.2-5.
13. 胡适宜.2005.被子植物生殖生物学[M].北京：高等教育出版社,232-247.
14. 胡适宜.2005.被子植物生殖生物学[M].北京：高等教育出版社,232-247。
15. 胡适宜.被子植物胚胎学[M].北京：高等教育出版社,1982：25-108.
16. 黄景华,王广金,孙岩,刁艳玲.小麦花粉管通道形成时期的研究[J].黑龙江农业科学,2004(2)：20-22.
17. 黄群策.2000.被子植物的无融合生殖[M].福州：福建科学技术出版社,76-78.
18. 黄双全,郭友好.2000.传粉生物学的研究进展.科学通报.45：225—237
19. 焦培培,李志军2007.濒危植物矮沙冬青开花物候研究[J],西北植物学报,Vo1.27(8)：1683-1689.
20. 李国泰,刘海滨.2004.蒲公英染色体核型分析.中国林副特产,,6：11-12
21. 李康.外来入侵植物牛膝菊的胚胎学研究[D],2010,东北林业大学.
22. 李懋学,陈瑞阳.1985.关于植物核型分析的标准化问题.武汉植物学研究,3(4)：297-302.
23. 李新蓉,谭敦炎.2007.新疆沙冬青(Ammopiptanthus nanus)的开花物候与环境的关系[J].中国沙漠,Vol.27(4)：572-577.
24. 李雪.2003.兰州百合小孢子母细胞减数分裂异常现象的观察[J].西北植物学报,Vol.23(10)：1796-1799.
25. 李岩坤,葛传吉.1989.蒲公英的细胞学研究.山东中医学院学报,13(2)：63—64,68
26. 梁铁兵,母锡金.1995.美味称猴桃和软枣称猴桃种间杂交花粉管行为和早期胚胎发生的观察[J].植物学报,Vol.7(8)：607-612.
27. 林蕙颖,郑君强,陈桂信,等.1995.柑桔不育性研究进展[J].福建果树,Vol.3(4)：13-15.
28. 凌定厚,马镇荣,陈梅芳.1991.起源于体细胞培养的釉稻雌性不育突变[J].遗传学报,,Vol.18(5)：446-451.
29. 刘大钧.细胞遗传学[M].北京：中国农业出版社,1999：117.
30. 刘林德,陈磊,张丽,等.2004.华北蓝盆花的开化特性及传粉生态学研究.生态学报,24(4)：718-723.
31. 刘林德,陈磊,张丽,等.2004.华北蓝盆花的开花特性及传粉生态学研究[J].生态学报,Vol.24(4)：71 8-723.
32. 刘林德,陈磊,张丽,等.华北蓝盆花的开花特性及传粉生态学研究[J].生态学报,2004,24(4)：718-723.
33. 刘林德,李玮,祝宁,等.2002.刺五加、短梗五加的花蜜分泌节律、花蜜成分及访花者多样性的比较研究[J].生态学报,Vol.22(6)：847-853.
34. 刘林德,张洪军,祝宁.刺五加花粉活力和柱头可授性的研究[].植物研究,2001,21(3)：376-380.
35.刘林德,张萍,张丽,等.2004.锦带花的花粉活力、柱头可授性及传粉者的观察[J].西北植物学报,,Vol.24(8)：1431-1434.
36. 刘志民,蒋德明,高红瑛.2003.植物生活史对策与干扰关系的研究[J].应用生态学报,14(3)：418-422。
37. 刘宗才,焦铸锦,董旭升,等.鸢尾的花部结构及繁育系统特征[J].园艺学报,2011,38(7)：1333～1340
38. 鲁先文,孙坤.2008.中国沙棘开花生物学的初步研究[J].云南植物研究,Vo1.30(3)：315-320
39. 吕琳、何聪芬.2005.木立芦荟小孢子母细胞减数分裂与花粉育性关系的初步研究[J].遗传,Vo1.27(3)：429-434
40. 马虹,王迎春,曹瑞等.2000.革苞菊胚胎学研究1.大小孢子发生和雌雄配子体发育[J].西北植物学报.20(3)：461-466.
41. 马文宝,施翔,张道远,等.2008.准噶尔无叶豆的开花物候与生殖特征[J].植物生态学报,Vo1.32(4)：760-767.
42. 孟玲,谭敦炎.2003.阿魏传粉昆虫及其访花行为的初步研究[J].西北植物学报,
43. 宁伟,吴杰,赵婷,等.2012.东北地区七种蒲公英核形态研究及其生殖方式初探[J].中国中药杂志.(3)：76-82.
44. 宁伟,吴杰,赵婷,等.东北地区七种蒲公英核型研究[J].中国中药杂志,2012,37(6)：771-776.
45. 彭艳琼,杨大荣,周芳,等.2003.木瓜榕传粉生物学[J].植物生态学报,Vol.27(1)：111-117
46. 邱英雄,傅承新.2001.明党参的濒危机制及其保护对策的研究[J].生物多样性,
47. 权秋梅,黎云祥,吴春梅,等.淫羊藿花粉萌发及花粉管生长研究[J].西北植物
48. 任明迅.雄蕊合生植物半边莲的花部综合征与繁育系统[J].植物生态学报,2009,33(2)：361-368.
49. 苏智先.1990.生殖生态学研究的现状与发展趋势[J].四川师范学院学报(自然科学版),9(3)：37-44.
50. 苏智先.生殖生态学的概念及其研究内容.常绿阔叶林生态学研究[M].重庆：西南师范大学出版社,1988
51. 孙颖.百子莲繁殖生物学研究[D].哈尔滨：东北林业大学,2009.1-2.
52. 唐岱,李明扬.菊花花粉萌发及花粉活力研究[J].西南农业大学学报,1993,15(4)：359-362.
53. 滕年军,陈发棣,马旭,等.2008.菊花脑大孢子发生、雌配子体与胚胎发育的研究[J].南京农业大学学报,31(4)：32-36..
54. 宛涛,孙启忠,蔡萍,等.2011.冷蒿小孢子分化过程的观察研究[J],中国草地学报,(33)1：97-101.
55. 王琼,苏智先,宋会兴,汤泽生.植物染色体数目及其变异与生境关系初探[J].生态学杂志,2001,20(5)：8-11.
56. 王仁忠,祖元刚,聂绍荃.1999.羊草种群生物量生殖分配的初步研究.应用生态学报,10(5)：553～555.
57. 王守军,杨晓杰,葛继荣等.2007.3种蒲公英的核型与进化.高师理科学刊,27(6)：49-52
58. 王四清,陈俊愉.菊花和几种其他菊科植物花粉的试管萌发[J].北京林业大学学报,1993,15(4)：56-60.
59. 王艳,闰丽梅,关雅静等.1998.戟片蒲公英的核型研究.齐齐哈尔大学学报,14(4)：58-60
60. 王英强,张奠湘,陈忠毅.2005.益智传粉生物学的研究[J].植物生态学报,Vo1.29(4)：599-609.
61. 王迎春,杨持.2001.物种生活策略的研究现状[J].内蒙古大学学报,32(1)：112-118
62. 卫星,申家恒.2003.羊草大、小孢子发生与雌雄配子体发育的观察[J].西北植物学报,Vo1.23(12)：2058-2066.
63. 吴雪莲,谭敦炎。异果芥的花部综合征及其繁育系统[J].植物分类学报,2007,45(4)：538-550.
64. 吴玉香,赵晓明.2003.山西蒲公英的有丝分裂观察及核型分析.山西农业大学学报,373-375
65. 肖宜安,何平,李晓红.2004.濒危植物长柄双花木的开花物候和生殖特征.生态学报,24,14～21.
66. 杨淑娟,宋玉霞,邓桦,等.2007.宁夏枸杞柱头和萌发花粉中钙分布特征[J].西北植物学报,Vo1.27(9)：1782-1789.
67. 姚雅琴,张改生.2001.小麦花药药壁表皮细胞结构与功能研究[J]西北植物学报21(2)273-277.
68. 于立恒.蒲公英药理作用研究进展[J]实用中医药杂志,2012,28(7)：617-620.
69. 于喜凤.1997.短命植物异喙菊胚胎学研究[J].《新疆师范大学学报)(自然科学版),16(4)：43-46.
70. 于晓英,卢向阳,龚明福等.瓜叶菊花粉生活力研究.湖南农业大学学报(自然科学版),2005,31(1)：42-46.
71. 翟大彤,安争夕,谭敦炎.1997.新疆蒲公英属有性生殖与无融合生殖植物的调查研究.西北植物学报,17(1)：1-7
72. 张波,吴志刚,刘文毅,等.蒲公英无融合生殖特性初探[J].沈阳农业大学,2011,42(4)：475-478.
73. 张波,吴志刚,刘文毅,等.蒲公英无融合生殖特性初探[J].沈阳农业大学,2011,42(4)：475-478.
74. 张彩琴,杨持.几种不同生活型草原植物生长动态的比较研究[J].内蒙古大学学报(自然科学版),2007,38(5)：557-564.
75. 张大勇.2004.植物生活史进化与繁殖生态学.科学出版社.
76. 张金菊,叶其刚,姚小洪,等.2008.片断化生境中濒危植物黄梅秤锤树的开花生物学、繁育系统与生殖成功的因素[J].植物生态学报, Vol.32(4)：743-750.
77. 张文辉,祖元刚,刘国彬.2002.十种濒危植物的种群生态学特征及致危因素分析.生态学报,22(9)：1512-1520
78. 张英涛,杨海东.1996.绒毡层研究进展.生物学通报,13(4)：6-13.
79. 张仲鸣,苏都莫日根,李正理.银杏小孢子中的微核形成及其在进化过程中的意义[J].植物学报,1997,39(2)：97-101
80. 赵宏波,陈发棣,房伟民.栽培小菊和几种菊属植物花粉离体萌发研究.南京农业大学学报,2005,28(2)：22-27.
81. 郑书馨,古松,江莎,等.2009.黄顶菊小孢子发生与雄配子体发育的研究[J].热带亚热带植 物学报,17(4)：321～327.
82.郑书馨.黄顶菊生殖生物学研究[D].2010,南开大学.
83.周红军,唐亮,马香.2003.土麦冬传粉生物学和交配系统的初步研究[J].北京师范大学学报(自然科学版),Vol.39(5)：669-673.
84.周纪伦.植物种群生态学.北京：高等教育出版社,1992：89-94.
85.周世良,洪德元.传粉生物学的最新进展和发展趋势.见：李承森.植物科学进展(第一卷).北京：高等教育出版社,1998
86.周正立,李志军,龚卫江,2005.高山胡杨、灰叶胡杨开花生物学特性研究[J].武汉植物学研究,23(2)：163-168.
87.朱丹,赵鑫,徐俏,等.东北地区11种蒲公英RP-HPLC指纹图谱研究[J].中国中药杂志,2011,36(7)：899-902.
88. Abe T.2001. Flowering phenology, display size and fruit set in an understory dioecious shrub, Aucuba japonica (Cornaceae).American Journal of Botany,88:455-461. 89. Adams KL, Wendel JF.Polyploidy and genome evolution in plants[J]. Curr Opin Plant Biol.2005, 8:135-141
90. Adelberg J W, Rhodes B B, Skorupska H T,et al. Explant origin affects the frequency of tetraploid plants from tissue cultures of melon[J].Hort Sci,1994,29 (6):689-692
91. Aguilar R, Ashworth L, Galetto L,et al.2006. Plant reproductive susceptibility to habitat fragmentation:review and synthesis through a meta-analysis. Ecol.Lett.9,968-980
92. Aizen, M.A.,Garibaldi L A.,. Cunningham S A, et al.2008. Long-term global trends in crop yield and production reveal no current pollination shortage but increasing pollinator dependency. Curr. Biol.18,1-4.
93. Andersen, M. C.1993. Diaspore morphology and seed dispersal in several wind-dispersed Asteraceae[J]. Am. J. Bot.,80:487-492.
94. Andrea B M, Roberto G J F, Maria S P, et al. Unusual cytological patterns of microsporogenesis in Brachiaria decumbens:abnormalities in spindle and defective cytokinesis causing precocious cellulari2ation[J]. Cell Biology International,2002,26(7):641-646
95. Aquilar R, Bernardello G, Galetto L.2002. Pollen-Pistil relationships and Pollen size-number trade-off in species of the tribe Lycieae(Solanaceae).J Plant Res 115:335-340.
96. Ashman T L.2002. The roles of herbivores in the evolution of separate sexes form hermaphroditism.Ecology,,83:1175-1184
97. Ashman, T.L. Knight, T M., Steets J A.,et al.2004. Pollen limitation of plant reproduction: ecological and evolutionary causes and consequences. Ecology 85,2408-2421
98. Asker S, Jerling L.1992. Apomixis in plants. CRC Press, Boca Raton;
99. Asker S, Jerling L.1992. Apomixis in plants. CRC Press, Boca Raton
100. Atlagic J, Dozet B, Koric S.1993. Meiosis and pollen viability in Helianthus tuberosus L. and its hybrids with cultivated sunflower[J]. Plant Breeding,,111:318-324.
101. Baker H. G., Baker 1.1982. Starchy and starch less pollen in the Onagraceae. Ann. Missouri Bot. Gard.69:748-754.
102. Barren S C H, Eckert C G.1990. Variation and evolution of plant mating systems. Kawano S.Biological approaches and evolutionary trends in plants. New York:Academic Press.
103. Barren S C H, Harder L D.1996. Ecology and evolution of plant mating. Trends in Evolution and Ecology.,11:7378
104. Barrett S C H.2002. Sexual interference of the floral kind.Heredity,88:154-159
105. Barrett S C H.1998.The evolution of mating strategies in flowering plants. Trends in Plant Science,3(9):335-341.
106. Bascompte, J. et al.2006. Asymmetric coevolutionary networks facilitate biodiversity maintenance. Science 312,431-433
107. Baskin CC, Baskin JM 2001..Seeds:ecology, biogeography, and evolution of dormancy and germination[M]. Academic, London,
108. Baskin CC, Baskin JM.1998.Seeds:Ecology, Biogeography, and Evolution of Dormancy and germination[M].Academic Press, San Diego,
109. Batygina T B.2002. Embryology ofFlowering Plants:Terminology and Concepts. Volume 1: Generative Organs ofFlower [M]. Enfield(New Hampshire):Science Publishers.
110. Bengtsson O, Ceplitis A.2000.The balance between sexual and asexual reproduction in plants living in variable environments. J Evol Biol 13:415-422
111. Bengtsson O, Ceplitis A.2000. The balance between sexual and asexual reproduction in plants living in variable environments. J Evol Biol 13:415-422
112. Bertin RI, Gwisc GM.2002. Floral sex ratios and gynomonoecy in Solidago (Asteraceae). Biol J Linn Soc 77:413-422
113. Bewley,J. D.1997. Seed germination and dormancy[M]. The Plant Cell,,9:1055-1066.
114. Bicknell RA, Koltunow AM (2004) Understanding apomixis:recent advances and remaining conundrums. PI Cell 16:228-245.
115. Bicknell RA, Koltunow AM.2004. Understanding apomixis:recent advances and remaining conundrums. PI Cell 16:228-245
116. Biesmeijer, J.C. et al.2006. Parallel declines in pollinators and insectpollinated plants in Britain and the Netherlands. Science 313,351-354
117. Bond, W.J.1994. Do mutualisms matter? Assessing the impact of pollinator and disperser disruption on plant extinction. Proc. R. Soc. Lond. B Biol. Sci.344,83-90
118. Bosch J. Retana J, CerdaX.1997.Flowering phenology, floral traits and pollinator composition in a herbaceous Mediterranean plant community. Oecologia,109:583-591.
119. Brewbaker J.L..1967. Distribution and phylogenetic significance of binucleate and trinucleate pollen grains in angiosperms. Am. J. Bot.54,1069-1083.
120. Bu HY, Chen XL, Xu XL,et al.2007. Community-wide germination strategies in analpine meadow on the eastern Qinghai-Tibet Plateau:phylogenetic and life-history correlates[J]. Plant Ecology,191,127-149.
121. Bu HY, Chen XL, Xu XL,et al.Seed mass and germination in alpine meadow onthe eastern Tsinghai-Tibet plateau[J]. Plant Ecology,2006,191,127-149
122. Burd, M.1994. Bateman principle and reproduction-the role of pollen limitation in fruit and seed set. Bot. Rev.60,83-139
123. Burtt B L. Compositae and the study of functional evolution[J]. Botanical Journal of Scotland, 1961,39,216-232.
124. Carman JG.1997. Asynchronous expression of duplicate genes in angiosperms may cause apomixis, bispory, tetraspory, and polyembryony. Biological Journal of the Linnean Society 61: 51-94。
125. Charnov E L. The theory of sex allocation monographs in population biology No.18.Princeton: Princeton Univ Press,1982
126. CHEN Shi-qiang, WANG Zhong, LIU Man-xi, XIE Zhao-wei, WANG Hui-hui. Pollen Grain Germination and Pollen Tube Growth in Pistil of Rice. Rice Science,2008,15(2):125-130
127. Cruden R W.1977. Pollen-ovule ratios:A conservative indicator of breeding systems in flowering plants.Evolution,31:32-46
128. Cruden RW, Lyon DL.1985. Correlations among stigma depth, style length, and Pollen grain size:do they reflect function or Phylogeny? Bot Gaz146:143-149.
129. Czapik R.1994. How to detect apomixis in Angiospermae. Polish Bot Stud 8:13-21
130. Dafni, Dafni A. Pollination Ecology:a Practical Approach. Oxford:Oxford University Press,1992.
131. Daher, F.B., Chebli, Y., Geitmann, A.,2009. Optimization of conditions for germination of cold-stored Arabidopsis thaliana pollen. Plant Cell Rep.28,347-357.
132. Devineau J L.1999. Seasonal rhythms and phonological plasticity of savanna woody species in a fallow farming system (southwest Burkina Faso) Journal of Tropical Ecology,15:497-513.
133. Dormann, C.F. et al.2008. Prediction uncertainty of environmental change effects on temperate European biodiversity. Ecol. Lett.11,235-244
134. Duan Y W, He Y P, Liu J Q.2005. Reproductive ecology of the Qinghai-Tibet Plateau endemic Gentiana straminea(Gentianaceae), a hermaphrodite perennial characterized by herkogamy and dichogamy. Acta Oecologica,27:225-232
135. Eckhart VM.1999. Sexual dimorphism in flowers and inflorescences. In:Geber MA, Dawson TE, Delph LF (eds) Gender and sexual dimorphism in flowering plants. Springer, Berlin, pp 123-148.
136. Fontaine, C. et al.2006. Functional diversity of plant-pollinator interaction webs enhances the persistence of plant communities.
137. Fortuna,M.A. and Bascompte, J.2006. Habitat loss and the structure of plant-animal mutualistic networks. Ecol. Lett.9,278-283
138. Gaonkar R V, Torne S G. Induced autotetraploidy in Ageratum conyzoides L.[J].Cytologia,1991,56 (3):327-331
139. Goulson, D. et al.2008. Decline and conservation of bumble bees. Annu. Rev. Entomol.53, 191-208
140. Graaf B H J, Derksen J W M, Mariani C.2001.Pollen and pistil in the progamic phase [J]. Sex Plant Reprod,14:41-45.
141. Gutterman Y.2000.Environmental factors and survival strategies of annual plant species in the Negev desert,Israel[J]. Plant Species Biology,,15,113-125.
142. Gutterman Y. Survival Strategies of Annual Desert Plants[M]. Berlin:Springer,2002.
143. Hacker JB. Polyploid distribution and seed dormancy in relation to provenance rainfall in the Digitaria milanjiana complex[J]. Aust J Bot,1988,36:693-700
144. Harder LD.1998.Pollen-size comparisons among animal-pollinated angiosperms with different pollination characteristies. Biol J Linn Soc 64:513-525.
145. He Y P, Duan Y W, Liu J Q, et al.2006. Floral closure in response to temperature and pollination in Gentiana straminea Maxim.(Gentianaceae),an alpine perennial in the Qinghai-Tibetan Plateau. Plant Systematics and Evolution,256:17-33.
146. Hegland, S.J. and Totland,0.2008. Is the magnitude of pollen limitation in a plant community affected by pollinator visitation and plant species specialisation levels? Oikos 117,883-891
147. Hendrickx, F. et al.2007. How landscape structure, land-use intensity and habitat diversity affect components of total arthropod diversity in agricultural landscapes. J. Appl. Ecol.44,340-351
148. Hiraga T, Sakai S.2007. The effects of inflorescence size and flower position on biomass and temporal sex allocation in Lobelia sessiliflora. Plant Ecol 188:205-214
149. Hiratsuka S, Zhang S L, Nakagawa E, et al. Selective inhibition of the growth or incompatible pollen tubes by S-protein in the Japanese pear[J]. Sex Plant Reprod,2000,13:209.
150. Hoehn, P. et al.2008. Functional group diversity of bee pollinators increases crop yield. Proc. R. Soc. Lond. B Biol. Sci.275,2283-2291
151. Hojsgaard DH, Honfi AI, Rua GH, Davina a JR.2009. Chromosome numbers and ploidy levels of Paspalum species from subtropical South America (Poaceae). Genetics Resources and Crop Evolution 56:533-545.
152. Holsinger, K. E.2000. Reproductive systems and evolution in vascular plants. Proceedings of the National Academy of Sciences,USA,97:7037-7042.
153. Hong L, Shen H, Ye W H, et al. Self-incompatibility in Mikania micrantha in South ChinafJ]. Weed research,2007,47:280-283.
154. Hoya A, Shibaike H, Morita T,et al. Germination and seedling survivorship characteristics of hybrids between native and alien species of dandelion (Taraxacum) [J]. Plant Species Biol,2004, 19:81-90。
155. Itagaki T, Sakai S.2006. Relationship between floral longevity and sex allocation among flowers within inflorescences in Aquilegia buergeriana var. oxysepala (Ranunculaceae). Am J Bot 93:1320-1327
156. Jaffe'e, R. et al.2010. Estimating the density of honeybee colonies across their natural range to fill the gap in pollinator decline censuses. Conserv. Biol.24,,583-593
157. Johri B M, Ambegaokar K B, Srivastava P S. Comparative Embryology of Angiosperms [M]. Berlin:Springer,1992.
158. Jolanta Marciniuk, Aleksandra Grabowska-Joachimiak and Pawel Marciniuk.2010. Differentiation of the pollen size in five representatives of Taraxacum sect. Palustria. Biologia, Volume 65, Number 6, Pages 954-957.
159. Joshi A, Moody ME.1998. The cost of sex revisited:effects of male gamete output of hermaphrodites that are asexual in their female capacity. J Theor Biol 195:533-542.
160. Julia Y C, Eliana R F.A.2004,triploid cytotype of Echinodorus tennellus[J].Aquatic Botany, 79:325-332.
161. Khazanehdari K A, Jones G H.1997. The causes and consequences of meiotic irregularity in the leek (Alliumampeloprasum spp.porrum);implications for fertility[J].Euphytica,93:313-319.
162. KIRSCHNER J.& STEPANEK J.1997. A nomenclatural checklist ofsupraspecific names in Taraxacum. Taxon 46:87-98.
163. KIRSCHNER J.& STEPANEK J.1998. A Revision of Taraxacum sect. Piesis (Compositae). Folia Geobot.33:391-414.
164. Klein, A.M. et al.2007. Importance of pollinators in changing landscapes for world crops. Proc. R. Soc. London B. Biol. Sci.274,303-313
165. Koduru P R K, Rao M K.1981.Cytogenetics of synaptic mutants in higher plants[J]. Theor Appl Genet,59(4):197-214.
166. Koltunow AM (1993) Apomixis:Embryo sacs and embryos formed without meiosis or fertilization in ovules. PI Cell 5:1437-1452
167. Korpelainen, H.1998. Labile sex expression in plants. Biological Reviews of the Cambridge Philosophical Society 73:157-180.
168. Krahulcova A, Papouskova S, Krahulec F (2004) Reproduction mode in the allopolyploid facultatively apomictic hawkweed Hieracium rubrum (Asteraceae, H. subgen. Pilosella). Hereditas (Lund)141:19-30
169. Krahulcova A, Papouskova S, Krahulec F.2004. Reproduction mode in the allopolyploid facultatively apomictic hawkweed Hieracium rubrum (Asteraceae, H. subgen. Pilosella). Hereditas (Lund)141:19-30.,
170. Le Conte, Y. and Navajas, M.2008. Climate change:impact on honey bee populations and diseases. Rev. Sci. Tech. Off. Int. Epizoot.27,499-510.
171. Leins P,Erbar C.2003.Floral developmental features and molecular data in plant systematics. In: Deep Morphology:Toward a Renaissance of Morphology in Plant Systematics (eds Stuessy TF,Mayer V,H?randl E),,pp.81-105.Ruggell, Ganther.
172. Lenka Martonfiova.2006. Possible pathways of the gene flow in Taxacum Sect. Ruderalia. Folia Geobotanica 41.183-201.
173. Li P, Huang H Y.2006. The genesis of microspore and the formation of male gametophyte in Swertia davii Franch. Bull Bot Res,26 (4):452-459.
174. L i Q J, Xu Z P, Kress W,J, et al. Flexible style that encourages outcrossing. Nature, 2001,410 (827):432
175. Lloyd, D. G. & S. C. H. Barrett.1996. Floral biology. New York:Chapman&Hall.
176. Lopez, H., Galetto, L., Anton, A.M.,2005. Pollen-pistil size correlation and pollen size-number trade-off in species of Argentinian Nyctaginaceae with different pollen reserves. Plant Syst. Evol.256,69-73.
177. Lord E. M., Ecka rd.1984. Incompatibility between the dimorphic flowers of Collomia grandiflora,a cleistogamous species. Science 223:695-696.
178. Lortie CJ, Aarssen LW.1999.The advantage of being tall:higher flowers receive more pollen in Verbascum thapsus L(Scrophulariaceae). Ecoscience 6:68-71
179. Losey, J.E. and Vaughan, M.2006. The economic value of ecological services provided by Insects. BioScience 311-323
180. Lovett Doust, J.&L. Lovett Doust. Plant reproductive ecology:patterns and strategies. Oxford: Oxford University Press.1988.
181. Lu XM, Zhou C F, An SQ, et al.2007. Phenotypic plasticity, allometry and invasiveness ofplants. Chinese Journal of Ecology,26:1438-1444.
182. Lu Y, Huang SQ.2006. Adaptive advantages of gynomonoecious species. Acta Phytotaxon Sin 44:231-239.
183. LUAN L, TU S B, LONG W B, et al.2007. Cytogenetic studies on two F1 hybrids of autotetraploid rice varieties showing extremely high level of heterosis[J].Plant Systematics and Evolution,267:205-213.
184. Lush W M, Clarke A E. Observations of pollen tube growth in Nicotiana alata and their implications for the mechanism of self-incompatibility [J]. Sex Plant Reprod,1997,10:27-35.
185. Mani M S, Saravanan,J M. Pollination ecology and evolution in Compositae (Asteraceae). New Hampshire:Science Publishers Inc,1999.
186. Marquis R J.1988. Phenological variation in the neotropical understory shrub Piper arieianum: causes and consequences. Ecology.69:1552-1565.
187. Matzk, F., Meister,A.,and Schubert,I. 2000. An efficient screen for reproductive pathways using mature seeds of monocots and dicots. Plant Journal,21,97-108.
188. Maynard Smith J.1978. The Evolution of Sex. Cambridge University Press:Cambridge.
189. McKinley, M. A.1989. Within and among plant variation in seed mass and pappus size in Tragopogon dubiou[J]s. Can. J. Bot.67:1298-1304.
190. Memmott, J. et al.2004. Tolerance of pollination networks to species extinctions. Proc. R. Soc. Lond. B Biol. Sci.271,2605-2611
191. Mert, C.,2009. Pollen morphology and anatomy of Cornelian cherry (Cornus masL.) cultivars. HortScience 44,519-522.
192. MH Verduijn, PJ Van Dijk and JMM Van Damme.2004. The role of tetraploids in the sexual-asexual cycle in dandelions (Taraxacum), Heredity,93,390-398
193. Mogie M.1992. The Evolution of Asexual Reproduction in Plants, Chapman & Hall:London
194. Moritz, R.F.A. et al.2007. The size of wild honeybee populations (Apis mellifera) and its implications for the conservation of honeybees. J. Insect Conserv.11,391-397
195. Mulcahy D. L.1983. Models of pollen tube competition in Geranium maculatum. In:Real L. (ed.) Pollination biology. Academic Press, London, pp.152-160.
196. Nakayama Y, Seno H, Matsuda H.2002. A population dynamic model for facultative agamosperms. J Theor Biol 215:253-262.
197. Natural Research Council.2006. Status of Pollinators in North America, National Academic Press
198. NavasM L, Gamier E.2002. Plasticity ofwhole plant and leaf traits inRubia peregrinain response to light, nutrient and water availability. Acta Oecologica,23:375-383.
199. Neumann, P. and Carreck, C.2010. Honey bee colony losses:a global perspective. J. Apic. Res. 49,1-6
200. Niu K C, LuoY J, CholerP, et al.2008. The role of biomass allocation strategy on diversity loss due to fertilization. Basic and Applied Ecology,9:485-493.
201. Nogler GA (1984) Gametophytic apomixis. In Johri BM (ed) Embryology of Angiosperms. Springer-Verlag, Berlin & Heidelberg, pp 475-518
202. Nogler GA.1984. Gametophytic apomixis. In Johri BM (ed) Embryology of Angiosperms. Springer-Verlag, Berlin & Heidelberg, pp 475-518
203. Oldroyd, B.P.2007. What's killing American honey bees? Plos Biol.5,1195-1199
204. Ollerton, J.&A.Lack.1992. Flowering phenology:an example of relaxation of natural selection. Trends in Ecology and Evolution,7:274-276.
205. Osborn TC, Pires JC, Birchler JA, et al. Understanding mechanisms of novel gene expression in polyploids[J]. Trends Genet,2003,19:141-147.
206. Peter van Baarlen, Peter J. van Dijk, Rolf F. Hoekstra et al.2000. Meiotic recombination in sexual diploid and apomictic triploid dandelions (Taraxacum officinale L.). Genome 43:827-835
207. Pezzani, F. and C. Montana.2006. Inter-and intraspecific variation in the germination response to light quality and scarification in grasses growing in two-phase mosaics of the Chihuahuan desertfJ]. Ann. Bot.,97:1063-1071.
208. Pickering, C.M.1995. Variation in flowering parameters within and among five species of Australian Alpine Ranunculus. Australian Journal of Botany,43:103-112
209. Potts, S.G. et al.2010. Declines of managed honeybees and beekeepers in Europe? J. Apic. Res. 49,15-22
210. Primack, R.B.1987. Relationships among flowers, fruits and seeds. Annual Review of Ecology and Systematics,18:409-430.
211. Rathcke B., Lacey E.P.1985. Phenological patterns of terrestrial plants. Annual Review of Ecology and Systematics,6:179-214
212. ReiserL, FischerR L. The ovule and the embryo sac [J]. Plant Cell,1993,5:1291-1301.
213. Richards AJ (1997) Plant breeding systems. Ed.2, Chapman & Hall, London
214. Richards AJ (2003) Apomixis in flowering plants:an overview. Philos Trans, Ser B 358:1085-1093;
215. Richards AJ.1986. Plant Breeding Systems. Allen & Unwin:London.
216. Richards AJ.1997.Plant breeding systems. Ed.2, Chapman & Hall, London
217. Richards AJ.2003.Apomixis in flowering plants:an overview. Philos Trans, Ser B 358:1085-1093
218. Richards AJ.1973. The origin of Taraxacum agamospecies. Botanical Journal of Linnean Society66:189-211.
219. Rortais, A. et al.2005. Modes of honeybees exposure to systemic insecticides:estimated amounts of contaminated pollen and nectar consumed by different categories of bees. Apidologie 36, 71-83
220. Sammataro, D. et al.2000. Parasitic mites of honey bees:life history, implications, and impact. Annu. Rev. Entomol.45,519-548.
221. Sarkissian TS, Harder LD.2001.Direct and indirect responses to selection on pollen size in Brassica rapa L. J Evol Biol14:456-468.
222. Savidan et al.2001; Bicknell RA, Koltunow AM (2004) Understanding apomixis:recent advances and remaining conundrums. PI Cell 16:228-245
223. Savidan Y, Carman JG, Dresselhaus T (eds) (2001) The flowering of apomixis:from mechanisms to genetic engineering. CIMMIT, IRD, European Commission DG VI (FAIR), Mexico, D.F.
224. Savidan Y, Carman JG, Dresselhaus T (eds).2001. The flowering of apomixis:from mechanisms to genetic engineering. CIMMIT, IRD, European Commission DG VI (FAIR), Mexico, D.F.
225. Savidan Y, Pernes J.1982. Diploid-tetraploid-dihaploid cycles and the evolution of Panicum maximum Jacq. Evolution 36:596-600
226. Sheldon, J. C. The behaviour of seeds in the soil III. The influence of seed morphology and the behaviour of seedlings on the establishment of plants from surface lying seeds[J]. J. Ecol,1974,62:47-66.
227. Shivanna, K.R., Sawhney, V.K.,1995. Polyethylene glycol improves the in vitro growth of Brassica pollen tubes without loss in germination. J. Exp. Bot.46,1771-1774.
228. Siddiqi I, Ganesh G, Grossniklaus U, et al.2000. The dyadgene is required for progression through female meiosis in Arabidopsis Development[J].American Journal of Botany, Vol.127:197-207.
229. Simpson, M. Value of the awn in establishing seed of Danthonia penicillata[J]. N. Z. J. Sci. Tech.1952,33:360-364.
230. Skordilis, A. and C. A. Thanos.1995. Seed stratification and germination strategy in the Mediterranean pines Pinus brutia and P. halepensis[J]. Seed Sci. Res,5:151-160.
231. Smith-Ramirez C, Armesto J J, Figueroa J.1998. Flowering, fruiting and seed germination in Chilean rain forest Myrtaceae:ecological and Phylogenetic constraints.Plant Ecology,136:119-131,
232. Stebbins G L.1971. Chromosomal evolution in higher plants. London:Edward Arnod Lid.
233. Stout, J. and Morales, C.L.2009.Ecological impacts of invasive alien species on bees. Apidologie 40,388-409
234. SudingK N, Collins S L, Gough L, et al.2005. Functional-and abundance-based mechanisms explain diversity loss due toN fertilization. Proceedings of theNationalAcademy ofSciences(USA),102: 4387-4392.
235. Suwan T, John N. Pollen viability and pollen tube growth following cont rolled pollination and t heir relation to low fruit production in teak(Tectona grandis L.f.) [J]. Annals of Botany,1997,80: 401-410.
236. Tarasjev A.1997.Flowering phenclogy in natural populations of Iris pumila.Ecography,20: 48-54.
237. Teng Nian jun, Chen Tong, Jin Biao, et al.2006. Abnormalities in pistil development result in low seed set inLeymus chinensis(Poaceae) [J].Flora,201:658-667
238. Torang P, Ehrlen J, Agren J.2006.Facilitation in an insect-pollinated herb with a floral display dimorphism. Ecology 87:2113-2117
239. Torices R, Mendez M, Gomez JM.2011.Where do monomorphic sexual systems fit in the evolution of dioecy? Insights from the largest family of Angiosperms. New Phytol 190:238-248
240. Torres C,2000.Pollen size evolution:correlation between Pollen volume and Pistil length In Asteraceae. Sex Plant Reprod 12:365-370.
241. Tylianakis, J.M. et al.2008. Global change and species interactions in terrestrial ecosystems. Ecol.Lett.11,1351-1363
242. Urbani M H,Quarin C L,Espinoza F.Penteado M I O,Rodrigues I F. Cytogeography and reproduction of the Paspalum simplex polyploidy complex[J]. Plant Systematics and Evolution,2002,236:99-105.
243. Utteridge TMA, Saunders RMK.2001. Sexual dimorphism and functional dioecy in Maesa perlarius and M. japonica (Maesaceae/Myrsinaceae). Biotropica 33:368-374
244. Van Dijk PJ, Tas ICQ, Falque M, Bakx-Schotman T.1999. Crosses between sexual and apomictic dandelions (Taraxacum). Ⅱ. The breakdown of apomixis. Heredity 83:715-721.
245. Van Dijk PJ, Van Baarlen P, De Jong JH.2003. The occurrence of phenotypically complementary apomixis-recombinants in crosses between sexual and apomictic dandelions (Taraxacum officinale). Sex Plant Repr 16:71-76.
246. van Dijk PJ, Vijverberg K (2005) The significance of apomixis in the evolution of the angiosperms:areappraisal. In Bakker FT, Chatrou LW, Gravendeel B, Pelser P (eds) Plant species-level systematics:new perspectives on pattern & process. Regnum Veg 143, Koeltz, Konigstein, pp 101-116
247. van Dijk PJ, Vijverberg K.2005.The significance of apomixis in the evolution of the angiosperms:areappraisal. In Bakker FT, Chatrou LW, Gravendeel B, Pelser P (eds) Plant species-level systematics:new perspectives on pattern & process. Regnum Veg 143, Koeltz, Konigstein, pp 101-116
248. vanEngelsdorp, D. et al.2008. A survey of honey bee colony losses in the U.S., Fall 2007 to Spring 2008. PLoS ONE 3, e4071.
249. Vanhoenacker D, Agren J, Ehrlen J.2006.Spatio-temporal variation in pollen limitation and reproductive success of two scape morphs in Primula farinosa. New Phytol 169:615-621
250. Verduijn MH, van Dijk PJ, van Damme JMM.2004. The role of tetraploids in the sexual-asexual cycle in dandelions (Taraxacum). Heredity 93:390-398
251. Vonhof MJ, Harder LD.1995. Size-number trade-offs and Pollen Production by papilionaceous legumes. Am J Bot82:230-238.
252. Wang C Y, Dang C L. Plant mating system and its evolutionary mechanism in relation to population adaptation. Journal of Wuhan Botanical 1999,17 (2):163-172.
253. Washitani I, Masuda M. A comparative study of the germination characteristics of seeds from a moist tall grassland community[J]. Funct Ecol,1990,4:543-557
254. Weiner J.2004. Allocation, plasticity and allometry in plants. Perspectives in PlantEcology Evolution and Systematics,6:207-215.
255. Weinzierl RP, Berthold K, Beukeboom LW, Michiels NK.1998. Reduced male allocation in the parthenogenetic hermaphrodite Dugesia polychroa. Evolution 52:109-115.
256. Wesche K, Ronnenberg K, Hensen 1.2005. Lack of sexual reproduction within mountain steppe populations of the clonal shrub Juniperus sabina L. in semi-arid southern Mongolia. Journal of Arid Environments 63:390-405.
257. Whitton J, Sears ChJ, Baack EJ, Otto SP.2008.The dynamic nature of apomixis in the angiosperms. Int J Pl Sci 169:169-182.
258. Widen B, Lindell T.1995. Flowering and fruiting phenology in two perennial herbs, Anemone pulsatilla and A.pratnesis (Ranunculaceae).Acta Universitatis upsaliensis Symbolae Botanicae Upsalienses,31:145-158.
259. Willson MF, Traveset A.2000The ecology of seed dispersal. In:Fenner M ed. Seed-The Ecology ofRegeneration in Plant Community 2nd edn[M]. CABI Publishing, New York,,26-103.
260. Wilson LM, Fehrer J, Brautigam S, Grosskopf G (2006) A new invasive hawkweed, Hieracium glomeratum (Lactuceae, Asteraceae), in the Pacific Northwest. Canad J Bot 84:133-142
261. Winfree, R. and Kremen, C.2009. Are ecosystem services stabilized by differences among species? A test using crop pollination. Proc. R. Soc. Lond. B Biol. Sci.276,229-237
262. Wise, M. J., and J. J. Cummins.2006. Strategies of Solanum carolinense for regulating maternal investment in response to foliar and floral herbivory. Journal of Ecology 94:629-636.
263. Wise MJ, Coffey LE, Abrahamson WG.2008.Nutrient stress and gall flies interact to affect floral-sex ratio in gynomonoecious Solidago altissima (Asteraceae). Am J Bot 95:1233-1239.
264. Wu G L, Du G Z.2007.Advances in pantmrphological growth strategy. World Sciences-Technology Reserch& Development,29:47-51.
265. Wyatt R,1983. Pollinator-plant interactions and the evolution of breeding systems//Read, L. ed. Pollination Biology. Orlando:Academic Press:51-95.
266. Zettler, L. W., T. Delaney, J. A.1998. Sunley. Seed propagation of the epiphytic orchid, Epidendrum conopseum R. Brown, using its endophytic fungus[J]. Selbyana,19:249-253.
2. 陈香,胡雪华,肖宜安,等.紫茉莉的花部综合特征与繁育系统[J].生态学杂志,2008,27(10)：1653～1658.
3. 陈勇,李宏庆,马炜梁2001..雀榕及其传粉昆虫传粉生态研究[J].生态学报,Vol.21(10)：1570-1574.
4. 董宽虎,米佳.2006.白羊草种群繁殖的数量特征.草地学报,14(3)：210-213.
5. 杜国祯.1994.不同温度梯度下亚高寒草甸常见物种的萌发特性研究[J].兰州大学学报(自然科学版),30：112-116.
6. 庚晓红,罗毅波,董鸣.2008.春兰(兰科)传粉生物学的研究[J].植物分类学报,Vol.46(2)：163-174.
7. 龚燕兵黄双全.2007.传粉昆虫行为的研究方法探讨[J].生物多样性,15(6)：576-583.
8. 郭友好.传粉生物学与植物进化.见：陈家宽,杨继主编,植物进化生物学[M].武汉：武汉大学出版社,1994.232-280.
9. 何维明,钟章成.1997.植物繁殖的概念及其研究内容[J].生态学杂志,14(6)：1-3
10. 何亚平,刘建全.2003.植物繁育系统研究的最新进展和评述.植物生态学报,27(2)：151-163
11. 何亚平,刘建全.2004.青藏高原高山植物麻花芜的传粉生态学研究[J].生态学报,Vol.24(2)：215-220.
12. 贺海霞.2006.濒危植物独叶草(毛莨科)的传粉生物学及繁育系统研究[D].西安：陕西师范大学出版社,.2-5.
13. 胡适宜.2005.被子植物生殖生物学[M].北京：高等教育出版社,232-247.
14. 胡适宜.2005.被子植物生殖生物学[M].北京：高等教育出版社,232-247。
15. 胡适宜.被子植物胚胎学[M].北京：高等教育出版社,1982：25-108.
16. 黄景华,王广金,孙岩,刁艳玲.小麦花粉管通道形成时期的研究[J].黑龙江农业科学,2004(2)：20-22.
17. 黄群策.2000.被子植物的无融合生殖[M].福州：福建科学技术出版社,76-78.
18. 黄双全,郭友好.2000.传粉生物学的研究进展.科学通报.45：225—237
19. 焦培培,李志军2007.濒危植物矮沙冬青开花物候研究[J],西北植物学报,Vo1.27(8)：1683-1689.
20. 李国泰,刘海滨.2004.蒲公英染色体核型分析.中国林副特产,,6：11-12
21. 李康.外来入侵植物牛膝菊的胚胎学研究[D],2010,东北林业大学.
22. 李懋学,陈瑞阳.1985.关于植物核型分析的标准化问题.武汉植物学研究,3(4)：297-302.
23. 李新蓉,谭敦炎.2007.新疆沙冬青(Ammopiptanthus nanus)的开花物候与环境的关系[J].中国沙漠,Vol.27(4)：572-577.
24. 李雪.2003.兰州百合小孢子母细胞减数分裂异常现象的观察[J].西北植物学报,Vol.23(10)：1796-1799.
25. 李岩坤,葛传吉.1989.蒲公英的细胞学研究.山东中医学院学报,13(2)：63—64,68
26. 梁铁兵,母锡金.1995.美味称猴桃和软枣称猴桃种间杂交花粉管行为和早期胚胎发生的观察[J].植物学报,Vol.7(8)：607-612.
27. 林蕙颖,郑君强,陈桂信,等.1995.柑桔不育性研究进展[J].福建果树,Vol.3(4)：13-15.
28. 凌定厚,马镇荣,陈梅芳.1991.起源于体细胞培养的釉稻雌性不育突变[J].遗传学报,,Vol.18(5)：446-451.
29. 刘大钧.细胞遗传学[M].北京：中国农业出版社,1999：117.
30. 刘林德,陈磊,张丽,等.2004.华北蓝盆花的开化特性及传粉生态学研究.生态学报,24(4)：718-723.
31. 刘林德,陈磊,张丽,等.2004.华北蓝盆花的开花特性及传粉生态学研究[J].生态学报,Vol.24(4)：71 8-723.
32. 刘林德,陈磊,张丽,等.华北蓝盆花的开花特性及传粉生态学研究[J].生态学报,2004,24(4)：718-723.
33. 刘林德,李玮,祝宁,等.2002.刺五加、短梗五加的花蜜分泌节律、花蜜成分及访花者多样性的比较研究[J].生态学报,Vol.22(6)：847-853.
34. 刘林德,张洪军,祝宁.刺五加花粉活力和柱头可授性的研究[].植物研究,2001,21(3)：376-380.
35.刘林德,张萍,张丽,等.2004.锦带花的花粉活力、柱头可授性及传粉者的观察[J].西北植物学报,,Vol.24(8)：1431-1434.
36. 刘志民,蒋德明,高红瑛.2003.植物生活史对策与干扰关系的研究[J].应用生态学报,14(3)：418-422。
37. 刘宗才,焦铸锦,董旭升,等.鸢尾的花部结构及繁育系统特征[J].园艺学报,2011,38(7)：1333～1340
38. 鲁先文,孙坤.2008.中国沙棘开花生物学的初步研究[J].云南植物研究,Vo1.30(3)：315-320
39. 吕琳、何聪芬.2005.木立芦荟小孢子母细胞减数分裂与花粉育性关系的初步研究[J].遗传,Vo1.27(3)：429-434
40. 马虹,王迎春,曹瑞等.2000.革苞菊胚胎学研究1.大小孢子发生和雌雄配子体发育[J].西北植物学报.20(3)：461-466.
41. 马文宝,施翔,张道远,等.2008.准噶尔无叶豆的开花物候与生殖特征[J].植物生态学报,Vo1.32(4)：760-767.
42. 孟玲,谭敦炎.2003.阿魏传粉昆虫及其访花行为的初步研究[J].西北植物学报,
43. 宁伟,吴杰,赵婷,等.2012.东北地区七种蒲公英核形态研究及其生殖方式初探[J].中国中药杂志.(3)：76-82.
44. 宁伟,吴杰,赵婷,等.东北地区七种蒲公英核型研究[J].中国中药杂志,2012,37(6)：771-776.
45. 彭艳琼,杨大荣,周芳,等.2003.木瓜榕传粉生物学[J].植物生态学报,Vol.27(1)：111-117
46. 邱英雄,傅承新.2001.明党参的濒危机制及其保护对策的研究[J].生物多样性,
47. 权秋梅,黎云祥,吴春梅,等.淫羊藿花粉萌发及花粉管生长研究[J].西北植物
48. 任明迅.雄蕊合生植物半边莲的花部综合征与繁育系统[J].植物生态学报,2009,33(2)：361-368.
49. 苏智先.1990.生殖生态学研究的现状与发展趋势[J].四川师范学院学报(自然科学版),9(3)：37-44.
50. 苏智先.生殖生态学的概念及其研究内容.常绿阔叶林生态学研究[M].重庆：西南师范大学出版社,1988
51. 孙颖.百子莲繁殖生物学研究[D].哈尔滨：东北林业大学,2009.1-2.
52. 唐岱,李明扬.菊花花粉萌发及花粉活力研究[J].西南农业大学学报,1993,15(4)：359-362.
53. 滕年军,陈发棣,马旭,等.2008.菊花脑大孢子发生、雌配子体与胚胎发育的研究[J].南京农业大学学报,31(4)：32-36..
54. 宛涛,孙启忠,蔡萍,等.2011.冷蒿小孢子分化过程的观察研究[J],中国草地学报,(33)1：97-101.
55. 王琼,苏智先,宋会兴,汤泽生.植物染色体数目及其变异与生境关系初探[J].生态学杂志,2001,20(5)：8-11.
56. 王仁忠,祖元刚,聂绍荃.1999.羊草种群生物量生殖分配的初步研究.应用生态学报,10(5)：553～555.
57. 王守军,杨晓杰,葛继荣等.2007.3种蒲公英的核型与进化.高师理科学刊,27(6)：49-52
58. 王四清,陈俊愉.菊花和几种其他菊科植物花粉的试管萌发[J].北京林业大学学报,1993,15(4)：56-60.
59. 王艳,闰丽梅,关雅静等.1998.戟片蒲公英的核型研究.齐齐哈尔大学学报,14(4)：58-60
60. 王英强,张奠湘,陈忠毅.2005.益智传粉生物学的研究[J].植物生态学报,Vo1.29(4)：599-609.
61. 王迎春,杨持.2001.物种生活策略的研究现状[J].内蒙古大学学报,32(1)：112-118
62. 卫星,申家恒.2003.羊草大、小孢子发生与雌雄配子体发育的观察[J].西北植物学报,Vo1.23(12)：2058-2066.
63. 吴雪莲,谭敦炎。异果芥的花部综合征及其繁育系统[J].植物分类学报,2007,45(4)：538-550.
64. 吴玉香,赵晓明.2003.山西蒲公英的有丝分裂观察及核型分析.山西农业大学学报,373-375
65. 肖宜安,何平,李晓红.2004.濒危植物长柄双花木的开花物候和生殖特征.生态学报,24,14～21.
66. 杨淑娟,宋玉霞,邓桦,等.2007.宁夏枸杞柱头和萌发花粉中钙分布特征[J].西北植物学报,Vo1.27(9)：1782-1789.
67. 姚雅琴,张改生.2001.小麦花药药壁表皮细胞结构与功能研究[J]西北植物学报21(2)273-277.
68. 于立恒.蒲公英药理作用研究进展[J]实用中医药杂志,2012,28(7)：617-620.
69. 于喜凤.1997.短命植物异喙菊胚胎学研究[J].《新疆师范大学学报)(自然科学版),16(4)：43-46.
70. 于晓英,卢向阳,龚明福等.瓜叶菊花粉生活力研究.湖南农业大学学报(自然科学版),2005,31(1)：42-46.
71. 翟大彤,安争夕,谭敦炎.1997.新疆蒲公英属有性生殖与无融合生殖植物的调查研究.西北植物学报,17(1)：1-7
72. 张波,吴志刚,刘文毅,等.蒲公英无融合生殖特性初探[J].沈阳农业大学,2011,42(4)：475-478.
73. 张波,吴志刚,刘文毅,等.蒲公英无融合生殖特性初探[J].沈阳农业大学,2011,42(4)：475-478.
74. 张彩琴,杨持.几种不同生活型草原植物生长动态的比较研究[J].内蒙古大学学报(自然科学版),2007,38(5)：557-564.
75. 张大勇.2004.植物生活史进化与繁殖生态学.科学出版社.
76. 张金菊,叶其刚,姚小洪,等.2008.片断化生境中濒危植物黄梅秤锤树的开花生物学、繁育系统与生殖成功的因素[J].植物生态学报, Vol.32(4)：743-750.
77. 张文辉,祖元刚,刘国彬.2002.十种濒危植物的种群生态学特征及致危因素分析.生态学报,22(9)：1512-1520
78. 张英涛,杨海东.1996.绒毡层研究进展.生物学通报,13(4)：6-13.
79. 张仲鸣,苏都莫日根,李正理.银杏小孢子中的微核形成及其在进化过程中的意义[J].植物学报,1997,39(2)：97-101
80. 赵宏波,陈发棣,房伟民.栽培小菊和几种菊属植物花粉离体萌发研究.南京农业大学学报,2005,28(2)：22-27.
81. 郑书馨,古松,江莎,等.2009.黄顶菊小孢子发生与雄配子体发育的研究[J].热带亚热带植 物学报,17(4)：321～327.
82.郑书馨.黄顶菊生殖生物学研究[D].2010,南开大学.
83.周红军,唐亮,马香.2003.土麦冬传粉生物学和交配系统的初步研究[J].北京师范大学学报(自然科学版),Vol.39(5)：669-673.
84.周纪伦.植物种群生态学.北京：高等教育出版社,1992：89-94.
85.周世良,洪德元.传粉生物学的最新进展和发展趋势.见：李承森.植物科学进展(第一卷).北京：高等教育出版社,1998
86.周正立,李志军,龚卫江,2005.高山胡杨、灰叶胡杨开花生物学特性研究[J].武汉植物学研究,23(2)：163-168.
87.朱丹,赵鑫,徐俏,等.东北地区11种蒲公英RP-HPLC指纹图谱研究[J].中国中药杂志,2011,36(7)：899-902.
88. Abe T.2001. Flowering phenology, display size and fruit set in an understory dioecious shrub, Aucuba japonica (Cornaceae).American Journal of Botany,88:455-461. 89. Adams KL, Wendel JF.Polyploidy and genome evolution in plants[J]. Curr Opin Plant Biol.2005, 8:135-141
90. Adelberg J W, Rhodes B B, Skorupska H T,et al. Explant origin affects the frequency of tetraploid plants from tissue cultures of melon[J].Hort Sci,1994,29 (6):689-692
91. Aguilar R, Ashworth L, Galetto L,et al.2006. Plant reproductive susceptibility to habitat fragmentation:review and synthesis through a meta-analysis. Ecol.Lett.9,968-980
92. Aizen, M.A.,Garibaldi L A.,. Cunningham S A, et al.2008. Long-term global trends in crop yield and production reveal no current pollination shortage but increasing pollinator dependency. Curr. Biol.18,1-4.
93. Andersen, M. C.1993. Diaspore morphology and seed dispersal in several wind-dispersed Asteraceae[J]. Am. J. Bot.,80:487-492.
94. Andrea B M, Roberto G J F, Maria S P, et al. Unusual cytological patterns of microsporogenesis in Brachiaria decumbens:abnormalities in spindle and defective cytokinesis causing precocious cellulari2ation[J]. Cell Biology International,2002,26(7):641-646
95. Aquilar R, Bernardello G, Galetto L.2002. Pollen-Pistil relationships and Pollen size-number trade-off in species of the tribe Lycieae(Solanaceae).J Plant Res 115:335-340.
96. Ashman T L.2002. The roles of herbivores in the evolution of separate sexes form hermaphroditism.Ecology,,83:1175-1184
97. Ashman, T.L. Knight, T M., Steets J A.,et al.2004. Pollen limitation of plant reproduction: ecological and evolutionary causes and consequences. Ecology 85,2408-2421
98. Asker S, Jerling L.1992. Apomixis in plants. CRC Press, Boca Raton;
99. Asker S, Jerling L.1992. Apomixis in plants. CRC Press, Boca Raton
100. Atlagic J, Dozet B, Koric S.1993. Meiosis and pollen viability in Helianthus tuberosus L. and its hybrids with cultivated sunflower[J]. Plant Breeding,,111:318-324.
101. Baker H. G., Baker 1.1982. Starchy and starch less pollen in the Onagraceae. Ann. Missouri Bot. Gard.69:748-754.
102. Barren S C H, Eckert C G.1990. Variation and evolution of plant mating systems. Kawano S.Biological approaches and evolutionary trends in plants. New York:Academic Press.
103. Barren S C H, Harder L D.1996. Ecology and evolution of plant mating. Trends in Evolution and Ecology.,11:7378
104. Barrett S C H.2002. Sexual interference of the floral kind.Heredity,88:154-159
105. Barrett S C H.1998.The evolution of mating strategies in flowering plants. Trends in Plant Science,3(9):335-341.
106. Bascompte, J. et al.2006. Asymmetric coevolutionary networks facilitate biodiversity maintenance. Science 312,431-433
107. Baskin CC, Baskin JM 2001..Seeds:ecology, biogeography, and evolution of dormancy and germination[M]. Academic, London,
108. Baskin CC, Baskin JM.1998.Seeds:Ecology, Biogeography, and Evolution of Dormancy and germination[M].Academic Press, San Diego,
109. Batygina T B.2002. Embryology ofFlowering Plants:Terminology and Concepts. Volume 1: Generative Organs ofFlower [M]. Enfield(New Hampshire):Science Publishers.
110. Bengtsson O, Ceplitis A.2000.The balance between sexual and asexual reproduction in plants living in variable environments. J Evol Biol 13:415-422
111. Bengtsson O, Ceplitis A.2000. The balance between sexual and asexual reproduction in plants living in variable environments. J Evol Biol 13:415-422
112. Bertin RI, Gwisc GM.2002. Floral sex ratios and gynomonoecy in Solidago (Asteraceae). Biol J Linn Soc 77:413-422
113. Bewley,J. D.1997. Seed germination and dormancy[M]. The Plant Cell,,9:1055-1066.
114. Bicknell RA, Koltunow AM (2004) Understanding apomixis:recent advances and remaining conundrums. PI Cell 16:228-245.
115. Bicknell RA, Koltunow AM.2004. Understanding apomixis:recent advances and remaining conundrums. PI Cell 16:228-245
116. Biesmeijer, J.C. et al.2006. Parallel declines in pollinators and insectpollinated plants in Britain and the Netherlands. Science 313,351-354
117. Bond, W.J.1994. Do mutualisms matter? Assessing the impact of pollinator and disperser disruption on plant extinction. Proc. R. Soc. Lond. B Biol. Sci.344,83-90
118. Bosch J. Retana J, CerdaX.1997.Flowering phenology, floral traits and pollinator composition in a herbaceous Mediterranean plant community. Oecologia,109:583-591.
119. Brewbaker J.L..1967. Distribution and phylogenetic significance of binucleate and trinucleate pollen grains in angiosperms. Am. J. Bot.54,1069-1083.
120. Bu HY, Chen XL, Xu XL,et al.2007. Community-wide germination strategies in analpine meadow on the eastern Qinghai-Tibet Plateau:phylogenetic and life-history correlates[J]. Plant Ecology,191,127-149.
121. Bu HY, Chen XL, Xu XL,et al.Seed mass and germination in alpine meadow onthe eastern Tsinghai-Tibet plateau[J]. Plant Ecology,2006,191,127-149
122. Burd, M.1994. Bateman principle and reproduction-the role of pollen limitation in fruit and seed set. Bot. Rev.60,83-139
123. Burtt B L. Compositae and the study of functional evolution[J]. Botanical Journal of Scotland, 1961,39,216-232.
124. Carman JG.1997. Asynchronous expression of duplicate genes in angiosperms may cause apomixis, bispory, tetraspory, and polyembryony. Biological Journal of the Linnean Society 61: 51-94。
125. Charnov E L. The theory of sex allocation monographs in population biology No.18.Princeton: Princeton Univ Press,1982
126. CHEN Shi-qiang, WANG Zhong, LIU Man-xi, XIE Zhao-wei, WANG Hui-hui. Pollen Grain Germination and Pollen Tube Growth in Pistil of Rice. Rice Science,2008,15(2):125-130
127. Cruden R W.1977. Pollen-ovule ratios:A conservative indicator of breeding systems in flowering plants.Evolution,31:32-46
128. Cruden RW, Lyon DL.1985. Correlations among stigma depth, style length, and Pollen grain size:do they reflect function or Phylogeny? Bot Gaz146:143-149.
129. Czapik R.1994. How to detect apomixis in Angiospermae. Polish Bot Stud 8:13-21
130. Dafni, Dafni A. Pollination Ecology:a Practical Approach. Oxford:Oxford University Press,1992.
131. Daher, F.B., Chebli, Y., Geitmann, A.,2009. Optimization of conditions for germination of cold-stored Arabidopsis thaliana pollen. Plant Cell Rep.28,347-357.
132. Devineau J L.1999. Seasonal rhythms and phonological plasticity of savanna woody species in a fallow farming system (southwest Burkina Faso) Journal of Tropical Ecology,15:497-513.
133. Dormann, C.F. et al.2008. Prediction uncertainty of environmental change effects on temperate European biodiversity. Ecol. Lett.11,235-244
134. Duan Y W, He Y P, Liu J Q.2005. Reproductive ecology of the Qinghai-Tibet Plateau endemic Gentiana straminea(Gentianaceae), a hermaphrodite perennial characterized by herkogamy and dichogamy. Acta Oecologica,27:225-232
135. Eckhart VM.1999. Sexual dimorphism in flowers and inflorescences. In:Geber MA, Dawson TE, Delph LF (eds) Gender and sexual dimorphism in flowering plants. Springer, Berlin, pp 123-148.
136. Fontaine, C. et al.2006. Functional diversity of plant-pollinator interaction webs enhances the persistence of plant communities.
137. Fortuna,M.A. and Bascompte, J.2006. Habitat loss and the structure of plant-animal mutualistic networks. Ecol. Lett.9,278-283
138. Gaonkar R V, Torne S G. Induced autotetraploidy in Ageratum conyzoides L.[J].Cytologia,1991,56 (3):327-331
139. Goulson, D. et al.2008. Decline and conservation of bumble bees. Annu. Rev. Entomol.53, 191-208
140. Graaf B H J, Derksen J W M, Mariani C.2001.Pollen and pistil in the progamic phase [J]. Sex Plant Reprod,14:41-45.
141. Gutterman Y.2000.Environmental factors and survival strategies of annual plant species in the Negev desert,Israel[J]. Plant Species Biology,,15,113-125.
142. Gutterman Y. Survival Strategies of Annual Desert Plants[M]. Berlin:Springer,2002.
143. Hacker JB. Polyploid distribution and seed dormancy in relation to provenance rainfall in the Digitaria milanjiana complex[J]. Aust J Bot,1988,36:693-700
144. Harder LD.1998.Pollen-size comparisons among animal-pollinated angiosperms with different pollination characteristies. Biol J Linn Soc 64:513-525.
145. He Y P, Duan Y W, Liu J Q, et al.2006. Floral closure in response to temperature and pollination in Gentiana straminea Maxim.(Gentianaceae),an alpine perennial in the Qinghai-Tibetan Plateau. Plant Systematics and Evolution,256:17-33.
146. Hegland, S.J. and Totland,0.2008. Is the magnitude of pollen limitation in a plant community affected by pollinator visitation and plant species specialisation levels? Oikos 117,883-891
147. Hendrickx, F. et al.2007. How landscape structure, land-use intensity and habitat diversity affect components of total arthropod diversity in agricultural landscapes. J. Appl. Ecol.44,340-351
148. Hiraga T, Sakai S.2007. The effects of inflorescence size and flower position on biomass and temporal sex allocation in Lobelia sessiliflora. Plant Ecol 188:205-214
149. Hiratsuka S, Zhang S L, Nakagawa E, et al. Selective inhibition of the growth or incompatible pollen tubes by S-protein in the Japanese pear[J]. Sex Plant Reprod,2000,13:209.
150. Hoehn, P. et al.2008. Functional group diversity of bee pollinators increases crop yield. Proc. R. Soc. Lond. B Biol. Sci.275,2283-2291
151. Hojsgaard DH, Honfi AI, Rua GH, Davina a JR.2009. Chromosome numbers and ploidy levels of Paspalum species from subtropical South America (Poaceae). Genetics Resources and Crop Evolution 56:533-545.
152. Holsinger, K. E.2000. Reproductive systems and evolution in vascular plants. Proceedings of the National Academy of Sciences,USA,97:7037-7042.
153. Hong L, Shen H, Ye W H, et al. Self-incompatibility in Mikania micrantha in South ChinafJ]. Weed research,2007,47:280-283.
154. Hoya A, Shibaike H, Morita T,et al. Germination and seedling survivorship characteristics of hybrids between native and alien species of dandelion (Taraxacum) [J]. Plant Species Biol,2004, 19:81-90。
155. Itagaki T, Sakai S.2006. Relationship between floral longevity and sex allocation among flowers within inflorescences in Aquilegia buergeriana var. oxysepala (Ranunculaceae). Am J Bot 93:1320-1327
156. Jaffe'e, R. et al.2010. Estimating the density of honeybee colonies across their natural range to fill the gap in pollinator decline censuses. Conserv. Biol.24,,583-593
157. Johri B M, Ambegaokar K B, Srivastava P S. Comparative Embryology of Angiosperms [M]. Berlin:Springer,1992.
158. Jolanta Marciniuk, Aleksandra Grabowska-Joachimiak and Pawel Marciniuk.2010. Differentiation of the pollen size in five representatives of Taraxacum sect. Palustria. Biologia, Volume 65, Number 6, Pages 954-957.
159. Joshi A, Moody ME.1998. The cost of sex revisited:effects of male gamete output of hermaphrodites that are asexual in their female capacity. J Theor Biol 195:533-542.
160. Julia Y C, Eliana R F.A.2004,triploid cytotype of Echinodorus tennellus[J].Aquatic Botany, 79:325-332.
161. Khazanehdari K A, Jones G H.1997. The causes and consequences of meiotic irregularity in the leek (Alliumampeloprasum spp.porrum);implications for fertility[J].Euphytica,93:313-319.
162. KIRSCHNER J.& STEPANEK J.1997. A nomenclatural checklist ofsupraspecific names in Taraxacum. Taxon 46:87-98.
163. KIRSCHNER J.& STEPANEK J.1998. A Revision of Taraxacum sect. Piesis (Compositae). Folia Geobot.33:391-414.
164. Klein, A.M. et al.2007. Importance of pollinators in changing landscapes for world crops. Proc. R. Soc. London B. Biol. Sci.274,303-313
165. Koduru P R K, Rao M K.1981.Cytogenetics of synaptic mutants in higher plants[J]. Theor Appl Genet,59(4):197-214.
166. Koltunow AM (1993) Apomixis:Embryo sacs and embryos formed without meiosis or fertilization in ovules. PI Cell 5:1437-1452
167. Korpelainen, H.1998. Labile sex expression in plants. Biological Reviews of the Cambridge Philosophical Society 73:157-180.
168. Krahulcova A, Papouskova S, Krahulec F (2004) Reproduction mode in the allopolyploid facultatively apomictic hawkweed Hieracium rubrum (Asteraceae, H. subgen. Pilosella). Hereditas (Lund)141:19-30
169. Krahulcova A, Papouskova S, Krahulec F.2004. Reproduction mode in the allopolyploid facultatively apomictic hawkweed Hieracium rubrum (Asteraceae, H. subgen. Pilosella). Hereditas (Lund)141:19-30.,
170. Le Conte, Y. and Navajas, M.2008. Climate change:impact on honey bee populations and diseases. Rev. Sci. Tech. Off. Int. Epizoot.27,499-510.
171. Leins P,Erbar C.2003.Floral developmental features and molecular data in plant systematics. In: Deep Morphology:Toward a Renaissance of Morphology in Plant Systematics (eds Stuessy TF,Mayer V,H?randl E),,pp.81-105.Ruggell, Ganther.
172. Lenka Martonfiova.2006. Possible pathways of the gene flow in Taxacum Sect. Ruderalia. Folia Geobotanica 41.183-201.
173. Li P, Huang H Y.2006. The genesis of microspore and the formation of male gametophyte in Swertia davii Franch. Bull Bot Res,26 (4):452-459.
174. L i Q J, Xu Z P, Kress W,J, et al. Flexible style that encourages outcrossing. Nature, 2001,410 (827):432
175. Lloyd, D. G. & S. C. H. Barrett.1996. Floral biology. New York:Chapman&Hall.
176. Lopez, H., Galetto, L., Anton, A.M.,2005. Pollen-pistil size correlation and pollen size-number trade-off in species of Argentinian Nyctaginaceae with different pollen reserves. Plant Syst. Evol.256,69-73.
177. Lord E. M., Ecka rd.1984. Incompatibility between the dimorphic flowers of Collomia grandiflora,a cleistogamous species. Science 223:695-696.
178. Lortie CJ, Aarssen LW.1999.The advantage of being tall:higher flowers receive more pollen in Verbascum thapsus L(Scrophulariaceae). Ecoscience 6:68-71
179. Losey, J.E. and Vaughan, M.2006. The economic value of ecological services provided by Insects. BioScience 311-323
180. Lovett Doust, J.&L. Lovett Doust. Plant reproductive ecology:patterns and strategies. Oxford: Oxford University Press.1988.
181. Lu XM, Zhou C F, An SQ, et al.2007. Phenotypic plasticity, allometry and invasiveness ofplants. Chinese Journal of Ecology,26:1438-1444.
182. Lu Y, Huang SQ.2006. Adaptive advantages of gynomonoecious species. Acta Phytotaxon Sin 44:231-239.
183. LUAN L, TU S B, LONG W B, et al.2007. Cytogenetic studies on two F1 hybrids of autotetraploid rice varieties showing extremely high level of heterosis[J].Plant Systematics and Evolution,267:205-213.
184. Lush W M, Clarke A E. Observations of pollen tube growth in Nicotiana alata and their implications for the mechanism of self-incompatibility [J]. Sex Plant Reprod,1997,10:27-35.
185. Mani M S, Saravanan,J M. Pollination ecology and evolution in Compositae (Asteraceae). New Hampshire:Science Publishers Inc,1999.
186. Marquis R J.1988. Phenological variation in the neotropical understory shrub Piper arieianum: causes and consequences. Ecology.69:1552-1565.
187. Matzk, F., Meister,A.,and Schubert,I. 2000. An efficient screen for reproductive pathways using mature seeds of monocots and dicots. Plant Journal,21,97-108.
188. Maynard Smith J.1978. The Evolution of Sex. Cambridge University Press:Cambridge.
189. McKinley, M. A.1989. Within and among plant variation in seed mass and pappus size in Tragopogon dubiou[J]s. Can. J. Bot.67:1298-1304.
190. Memmott, J. et al.2004. Tolerance of pollination networks to species extinctions. Proc. R. Soc. Lond. B Biol. Sci.271,2605-2611
191. Mert, C.,2009. Pollen morphology and anatomy of Cornelian cherry (Cornus masL.) cultivars. HortScience 44,519-522.
192. MH Verduijn, PJ Van Dijk and JMM Van Damme.2004. The role of tetraploids in the sexual-asexual cycle in dandelions (Taraxacum), Heredity,93,390-398
193. Mogie M.1992. The Evolution of Asexual Reproduction in Plants, Chapman & Hall:London
194. Moritz, R.F.A. et al.2007. The size of wild honeybee populations (Apis mellifera) and its implications for the conservation of honeybees. J. Insect Conserv.11,391-397
195. Mulcahy D. L.1983. Models of pollen tube competition in Geranium maculatum. In:Real L. (ed.) Pollination biology. Academic Press, London, pp.152-160.
196. Nakayama Y, Seno H, Matsuda H.2002. A population dynamic model for facultative agamosperms. J Theor Biol 215:253-262.
197. Natural Research Council.2006. Status of Pollinators in North America, National Academic Press
198. NavasM L, Gamier E.2002. Plasticity ofwhole plant and leaf traits inRubia peregrinain response to light, nutrient and water availability. Acta Oecologica,23:375-383.
199. Neumann, P. and Carreck, C.2010. Honey bee colony losses:a global perspective. J. Apic. Res. 49,1-6
200. Niu K C, LuoY J, CholerP, et al.2008. The role of biomass allocation strategy on diversity loss due to fertilization. Basic and Applied Ecology,9:485-493.
201. Nogler GA (1984) Gametophytic apomixis. In Johri BM (ed) Embryology of Angiosperms. Springer-Verlag, Berlin & Heidelberg, pp 475-518
202. Nogler GA.1984. Gametophytic apomixis. In Johri BM (ed) Embryology of Angiosperms. Springer-Verlag, Berlin & Heidelberg, pp 475-518
203. Oldroyd, B.P.2007. What's killing American honey bees? Plos Biol.5,1195-1199
204. Ollerton, J.&A.Lack.1992. Flowering phenology:an example of relaxation of natural selection. Trends in Ecology and Evolution,7:274-276.
205. Osborn TC, Pires JC, Birchler JA, et al. Understanding mechanisms of novel gene expression in polyploids[J]. Trends Genet,2003,19:141-147.
206. Peter van Baarlen, Peter J. van Dijk, Rolf F. Hoekstra et al.2000. Meiotic recombination in sexual diploid and apomictic triploid dandelions (Taraxacum officinale L.). Genome 43:827-835
207. Pezzani, F. and C. Montana.2006. Inter-and intraspecific variation in the germination response to light quality and scarification in grasses growing in two-phase mosaics of the Chihuahuan desertfJ]. Ann. Bot.,97:1063-1071.
208. Pickering, C.M.1995. Variation in flowering parameters within and among five species of Australian Alpine Ranunculus. Australian Journal of Botany,43:103-112
209. Potts, S.G. et al.2010. Declines of managed honeybees and beekeepers in Europe? J. Apic. Res. 49,15-22
210. Primack, R.B.1987. Relationships among flowers, fruits and seeds. Annual Review of Ecology and Systematics,18:409-430.
211. Rathcke B., Lacey E.P.1985. Phenological patterns of terrestrial plants. Annual Review of Ecology and Systematics,6:179-214
212. ReiserL, FischerR L. The ovule and the embryo sac [J]. Plant Cell,1993,5:1291-1301.
213. Richards AJ (1997) Plant breeding systems. Ed.2, Chapman & Hall, London
214. Richards AJ (2003) Apomixis in flowering plants:an overview. Philos Trans, Ser B 358:1085-1093;
215. Richards AJ.1986. Plant Breeding Systems. Allen & Unwin:London.
216. Richards AJ.1997.Plant breeding systems. Ed.2, Chapman & Hall, London
217. Richards AJ.2003.Apomixis in flowering plants:an overview. Philos Trans, Ser B 358:1085-1093
218. Richards AJ.1973. The origin of Taraxacum agamospecies. Botanical Journal of Linnean Society66:189-211.
219. Rortais, A. et al.2005. Modes of honeybees exposure to systemic insecticides:estimated amounts of contaminated pollen and nectar consumed by different categories of bees. Apidologie 36, 71-83
220. Sammataro, D. et al.2000. Parasitic mites of honey bees:life history, implications, and impact. Annu. Rev. Entomol.45,519-548.
221. Sarkissian TS, Harder LD.2001.Direct and indirect responses to selection on pollen size in Brassica rapa L. J Evol Biol14:456-468.
222. Savidan et al.2001; Bicknell RA, Koltunow AM (2004) Understanding apomixis:recent advances and remaining conundrums. PI Cell 16:228-245
223. Savidan Y, Carman JG, Dresselhaus T (eds) (2001) The flowering of apomixis:from mechanisms to genetic engineering. CIMMIT, IRD, European Commission DG VI (FAIR), Mexico, D.F.
224. Savidan Y, Carman JG, Dresselhaus T (eds).2001. The flowering of apomixis:from mechanisms to genetic engineering. CIMMIT, IRD, European Commission DG VI (FAIR), Mexico, D.F.
225. Savidan Y, Pernes J.1982. Diploid-tetraploid-dihaploid cycles and the evolution of Panicum maximum Jacq. Evolution 36:596-600
226. Sheldon, J. C. The behaviour of seeds in the soil III. The influence of seed morphology and the behaviour of seedlings on the establishment of plants from surface lying seeds[J]. J. Ecol,1974,62:47-66.
227. Shivanna, K.R., Sawhney, V.K.,1995. Polyethylene glycol improves the in vitro growth of Brassica pollen tubes without loss in germination. J. Exp. Bot.46,1771-1774.
228. Siddiqi I, Ganesh G, Grossniklaus U, et al.2000. The dyadgene is required for progression through female meiosis in Arabidopsis Development[J].American Journal of Botany, Vol.127:197-207.
229. Simpson, M. Value of the awn in establishing seed of Danthonia penicillata[J]. N. Z. J. Sci. Tech.1952,33:360-364.
230. Skordilis, A. and C. A. Thanos.1995. Seed stratification and germination strategy in the Mediterranean pines Pinus brutia and P. halepensis[J]. Seed Sci. Res,5:151-160.
231. Smith-Ramirez C, Armesto J J, Figueroa J.1998. Flowering, fruiting and seed germination in Chilean rain forest Myrtaceae:ecological and Phylogenetic constraints.Plant Ecology,136:119-131,
232. Stebbins G L.1971. Chromosomal evolution in higher plants. London:Edward Arnod Lid.
233. Stout, J. and Morales, C.L.2009.Ecological impacts of invasive alien species on bees. Apidologie 40,388-409
234. SudingK N, Collins S L, Gough L, et al.2005. Functional-and abundance-based mechanisms explain diversity loss due toN fertilization. Proceedings of theNationalAcademy ofSciences(USA),102: 4387-4392.
235. Suwan T, John N. Pollen viability and pollen tube growth following cont rolled pollination and t heir relation to low fruit production in teak(Tectona grandis L.f.) [J]. Annals of Botany,1997,80: 401-410.
236. Tarasjev A.1997.Flowering phenclogy in natural populations of Iris pumila.Ecography,20: 48-54.
237. Teng Nian jun, Chen Tong, Jin Biao, et al.2006. Abnormalities in pistil development result in low seed set inLeymus chinensis(Poaceae) [J].Flora,201:658-667
238. Torang P, Ehrlen J, Agren J.2006.Facilitation in an insect-pollinated herb with a floral display dimorphism. Ecology 87:2113-2117
239. Torices R, Mendez M, Gomez JM.2011.Where do monomorphic sexual systems fit in the evolution of dioecy? Insights from the largest family of Angiosperms. New Phytol 190:238-248
240. Torres C,2000.Pollen size evolution:correlation between Pollen volume and Pistil length In Asteraceae. Sex Plant Reprod 12:365-370.
241. Tylianakis, J.M. et al.2008. Global change and species interactions in terrestrial ecosystems. Ecol.Lett.11,1351-1363
242. Urbani M H,Quarin C L,Espinoza F.Penteado M I O,Rodrigues I F. Cytogeography and reproduction of the Paspalum simplex polyploidy complex[J]. Plant Systematics and Evolution,2002,236:99-105.
243. Utteridge TMA, Saunders RMK.2001. Sexual dimorphism and functional dioecy in Maesa perlarius and M. japonica (Maesaceae/Myrsinaceae). Biotropica 33:368-374
244. Van Dijk PJ, Tas ICQ, Falque M, Bakx-Schotman T.1999. Crosses between sexual and apomictic dandelions (Taraxacum). Ⅱ. The breakdown of apomixis. Heredity 83:715-721.
245. Van Dijk PJ, Van Baarlen P, De Jong JH.2003. The occurrence of phenotypically complementary apomixis-recombinants in crosses between sexual and apomictic dandelions (Taraxacum officinale). Sex Plant Repr 16:71-76.
246. van Dijk PJ, Vijverberg K (2005) The significance of apomixis in the evolution of the angiosperms:areappraisal. In Bakker FT, Chatrou LW, Gravendeel B, Pelser P (eds) Plant species-level systematics:new perspectives on pattern & process. Regnum Veg 143, Koeltz, Konigstein, pp 101-116
247. van Dijk PJ, Vijverberg K.2005.The significance of apomixis in the evolution of the angiosperms:areappraisal. In Bakker FT, Chatrou LW, Gravendeel B, Pelser P (eds) Plant species-level systematics:new perspectives on pattern & process. Regnum Veg 143, Koeltz, Konigstein, pp 101-116
248. vanEngelsdorp, D. et al.2008. A survey of honey bee colony losses in the U.S., Fall 2007 to Spring 2008. PLoS ONE 3, e4071.
249. Vanhoenacker D, Agren J, Ehrlen J.2006.Spatio-temporal variation in pollen limitation and reproductive success of two scape morphs in Primula farinosa. New Phytol 169:615-621
250. Verduijn MH, van Dijk PJ, van Damme JMM.2004. The role of tetraploids in the sexual-asexual cycle in dandelions (Taraxacum). Heredity 93:390-398
251. Vonhof MJ, Harder LD.1995. Size-number trade-offs and Pollen Production by papilionaceous legumes. Am J Bot82:230-238.
252. Wang C Y, Dang C L. Plant mating system and its evolutionary mechanism in relation to population adaptation. Journal of Wuhan Botanical 1999,17 (2):163-172.
253. Washitani I, Masuda M. A comparative study of the germination characteristics of seeds from a moist tall grassland community[J]. Funct Ecol,1990,4:543-557
254. Weiner J.2004. Allocation, plasticity and allometry in plants. Perspectives in PlantEcology Evolution and Systematics,6:207-215.
255. Weinzierl RP, Berthold K, Beukeboom LW, Michiels NK.1998. Reduced male allocation in the parthenogenetic hermaphrodite Dugesia polychroa. Evolution 52:109-115.
256. Wesche K, Ronnenberg K, Hensen 1.2005. Lack of sexual reproduction within mountain steppe populations of the clonal shrub Juniperus sabina L. in semi-arid southern Mongolia. Journal of Arid Environments 63:390-405.
257. Whitton J, Sears ChJ, Baack EJ, Otto SP.2008.The dynamic nature of apomixis in the angiosperms. Int J Pl Sci 169:169-182.
258. Widen B, Lindell T.1995. Flowering and fruiting phenology in two perennial herbs, Anemone pulsatilla and A.pratnesis (Ranunculaceae).Acta Universitatis upsaliensis Symbolae Botanicae Upsalienses,31:145-158.
259. Willson MF, Traveset A.2000The ecology of seed dispersal. In:Fenner M ed. Seed-The Ecology ofRegeneration in Plant Community 2nd edn[M]. CABI Publishing, New York,,26-103.
260. Wilson LM, Fehrer J, Brautigam S, Grosskopf G (2006) A new invasive hawkweed, Hieracium glomeratum (Lactuceae, Asteraceae), in the Pacific Northwest. Canad J Bot 84:133-142
261. Winfree, R. and Kremen, C.2009. Are ecosystem services stabilized by differences among species? A test using crop pollination. Proc. R. Soc. Lond. B Biol. Sci.276,229-237
262. Wise, M. J., and J. J. Cummins.2006. Strategies of Solanum carolinense for regulating maternal investment in response to foliar and floral herbivory. Journal of Ecology 94:629-636.
263. Wise MJ, Coffey LE, Abrahamson WG.2008.Nutrient stress and gall flies interact to affect floral-sex ratio in gynomonoecious Solidago altissima (Asteraceae). Am J Bot 95:1233-1239.
264. Wu G L, Du G Z.2007.Advances in pantmrphological growth strategy. World Sciences-Technology Reserch& Development,29:47-51.
265. Wyatt R,1983. Pollinator-plant interactions and the evolution of breeding systems//Read, L. ed. Pollination Biology. Orlando:Academic Press:51-95.
266. Zettler, L. W., T. Delaney, J. A.1998. Sunley. Seed propagation of the epiphytic orchid, Epidendrum conopseum R. Brown, using its endophytic fungus[J]. Selbyana,19:249-253.