机械收获模式下直播冬油菜密度与行距的优化
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摘要
以华油杂62为材料,采用裂区设计,设置密度15万株hm~(–2)(D1)、30万株hm~(–2)(D2)、45万株hm~(–2)(D3)为主区;行距15 cm(R15)、25 cm(R25)、35 cm(R35)为裂区,研究密度及行距变化对油菜群体人工收获产量、叶面积指数(LAI)、角果皮面积指数(PAI)、透光率、抗倒伏、抗裂角性能及机械收获产量的影响,探讨透光率与产量、抗倒性的关系,建立机械化生产模式下油菜密度及行距最优配置。结果表明,密度增加或行距减小,油菜成株率适宜,LAI、PAI值增加,冠层透光率下降,群体生物量及经济系数增加,人工收获产量增加;但单位LAI(PAI)光拦截量、单株生物量及根干重下降,且较低的单位LAI(PAI)光拦截量有利于提高油菜经济系数;密度及行距处理间差异及互作效应显著,与农户习惯种植模式(D2R25)相比,在D3R15处理下可增产14.1%,获得最高人工收获产量。密度或行距增加,地上部鲜重、株高降低及根冠比增加,导致油菜茎秆、根倒角度下降,抗裂角指数增加,机械收获产量变化趋势与人工收获产量一致,与机械收获总损失率相反,表明除通过提高油菜抗倒性和抗裂角性降低机收损失外,较高的人工收获产量是获得较高机械收获产量的前提。由回归方程可知,与常规30万株hm~(–2)密度、25 cm行距配置比,密度43.8万株hm~(–2)和行距21 cm配置可使蕾薹期LAI提高21.02%、透光率及单位LAI光拦截量分别下降32.47%与17.36%,角果期PAI增加15.08%、透光率及单位PAI光拦截量分别下降32.04%与3.30%,获得较高的机械收获产量,进一步提高油菜机械化生产效益。
The field experiment was conducted with the cultivar Huayouza 62, which was seeded at 15(R15), 25(R15), and 30(R15) cm in row spacing and 15(D1), 30(D2), and 45(D3) ×10~4 plants hm~(–2) in density. The theoretical yield, leaf area index(LAI), pod area index(PAI), mechanical-harvested yield and yield loss were measured and calculated. Results showed that plant density and row spacing significantly affected the seed yield of rapeseed. The yield was increased as the plant density increased or row spacing reduced. Compared with the planting patterns used by farmers(D2R25), D3R15 could achieve 14.1% increase in yield, which was the highest yield among all the treatments because of appropriate mortality, the highest LAI, PAI and the light interception(LI). Population biomass had the similar trend with yield while harvest index(HI) significantly increased with increasing plant density and row spacing. HI was significantly and negatively correlated with LI/ LAI(PAI), indicating that lower LI/ LAI(PAI) was favorable for increasing HI. Plant height and aboveground biomass reduced and root/shoot ratio increased with increasing plant density and row spacing, which led to decrease root and stem lodging. Improvement in resistance to pod shattering was also observed as plant density and row spacing increased. These changes all contributed to mechanical harvesting operations, resulting in reducing yield loss. As the regression equations showed, compared with D2R25, 43.8×10~4 plants ha~(–1) in combination with 21 cm row spacing was optimum for rapeseed to maximize seed yield and minimize lodging and pod shattering so as to facilitate mechanical harvest. The combination could make the LAI increase by 21.02%, light transmittance(LT) and LI/LAI decrease by 32.47% and 17.36%; PAI increase by 15.08%, LT and LI/PAI decrease by 32.04% and 3.30%.
The field experiment was conducted with the cultivar Huayouza 62, which was seeded at 15(R15), 25(R15), and 30(R15) cm in row spacing and 15(D1), 30(D2), and 45(D3) ×10~4 plants hm~(–2) in density. The theoretical yield, leaf area index(LAI), pod area index(PAI), mechanical-harvested yield and yield loss were measured and calculated. Results showed that plant density and row spacing significantly affected the seed yield of rapeseed. The yield was increased as the plant density increased or row spacing reduced. Compared with the planting patterns used by farmers(D2R25), D3R15 could achieve 14.1% increase in yield, which was the highest yield among all the treatments because of appropriate mortality, the highest LAI, PAI and the light interception(LI). Population biomass had the similar trend with yield while harvest index(HI) significantly increased with increasing plant density and row spacing. HI was significantly and negatively correlated with LI/ LAI(PAI), indicating that lower LI/ LAI(PAI) was favorable for increasing HI. Plant height and aboveground biomass reduced and root/shoot ratio increased with increasing plant density and row spacing, which led to decrease root and stem lodging. Improvement in resistance to pod shattering was also observed as plant density and row spacing increased. These changes all contributed to mechanical harvesting operations, resulting in reducing yield loss. As the regression equations showed, compared with D2R25, 43.8×10~4 plants ha~(–1) in combination with 21 cm row spacing was optimum for rapeseed to maximize seed yield and minimize lodging and pod shattering so as to facilitate mechanical harvest. The combination could make the LAI increase by 21.02%, light transmittance(LT) and LI/LAI decrease by 32.47% and 17.36%; PAI increase by 15.08%, LT and LI/PAI decrease by 32.04% and 3.30%.
引文
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[2]苏伟,鲁剑巍,周广生,李小坤,韩自航,雷海霞.免耕及直播密度对油菜生长、养分吸收和产量的影响.中国农业科学,2011,44:1519-1526Su W,Lu J W,Zhou G S,Li X K,Han Z H,Lei H X.Effect of no-tillage and direct sowing density on growth,nutrient uptake and yield of rapeseed(Brassica napus L.).Sci Agric Sin,2011,44:1519-1526(in Chinese with English abstract)
[3]杨文平,郭天财,刘胜波,王晨阳,王永华,马冬云.行距配置对‘兰考矮早八’小麦后期群体冠层结构及其微环境的影响.植物生态学报,2008,32:485-490Yang W P,Guo T C,Liu S B,Wang C Y,Wang Y H,Ma D Y.Effects of row spacing in winter wheat on canopy structure and microclimate in later growth stage.J Plant Ecol,2008,32:485-490(in Chinese with English abstract)
[4]郑亭,陈溢,樊高琼,李金刚,李朝苏,荣晓椒,李国瑞,杨文钰,郭翔.株行配置对带状条播小麦群体光环境及抗倒伏性能的影响.中国农业科学,2013,46:1571-1582Zheng T,Chen Y,Fan G Q,Li J G,Li C S,Rong X J,Li G R,Yang W Y,Guo X.Effects of plant and row allocation on population light environment and lodging resistance of strip sown wheat in drill.Sci Agric Sin,2013,46:1571-1582(in Chinese with English abstract)
[5]王俊生,李少钦,张耀文,不同栽培密度对紧凑型油菜产量和主要性状的影响.耕作与栽培,2006,(3):25-26Wang J S,Li S Q,Zhang Y W.Effects of plant density on yield and main characters of rapeseed.Tillage&Cultivation,2006,(3):25-26(in Chinese)
[6]宋稀,刘凤兰,郑普英,张学昆,陆光远,付桂萍,程勇.高密度种植专用油菜重要农艺性状与产量的关系分析.中国农业科学,2010,43:1800-1806Song X,Liu F L,Zheng P Y,Zhang X K,Lu G Y,Fu G P,Cheng Y.Correlation analysis between agronomic traits and yield of rapeseed(Brassica napus L.)for high-density planting.Sci Agric Sin,2010,43:1800-1806(in Chinese with English abstract)
[7]张传胜.油菜生产机械化配套农艺技术的研究.中国农机化学报,2008,(6):91-94Zhang C S.Sutdy on suitale cultivating technology for mechanical production of rape.J Chin Agric Mech,2008,(6):91-94(in Chinese)
[8]Leach J E,Stevenson H J,Rainbow A J,Mullen L A.Effects of high plant populations on the growth and yield of winter oilseed rape(Brassica napus L.).J Agric Sci,1999,132:173-180
[9]陈新军,戚存扣,高建芹,伍贻美.不同栽培密度对杂交油菜产量的影响.江苏农业科学,2001,(1):29-30Chen X J,Qi C K,Gao J Q,Wu Y M.The influence of planting density on yield of hybrid rape.Jiangsu Agric Sci,2001,(1):29-30(in Chinese)
[10]李爱民,张永泰,惠飞虎,周如美,钱善勤,范琦.适合全程机械化作业的油菜育种新概念.中国农学通报,2005,21(11):151-153Li A M,Zhang Y T,Hui F H,Zhou R M,Qian S Q,Fan Q.Certain concepts concerning rapeseed(Brassica napus L.)varieties which suit to whole process mechanization operation.Chin Agric Sci Bull,2005,21(11):151-153(in Chinese)
[11]董晓芳,田保明,姚永芳,张艳,张京涛,孙弋媛,刘云霞,申龙,苏彦华.密度对油菜品种机械化收获特性的影响.中国农学通报,2012,28(3):71-74Dong X F,Tian B M,Yao Y F,Zhang Y,Zhang J T,Sun Y Y,Liu Y X,Shen L,Su Y H.Effects of the density on the characteristics of the mechanization harvest in Brassica napus L.Chin Agric Sci Bull,2012,28(3):71-74(in Chinese)
[12]Stamp P,Kiel C.Root morphology of maize and its relationship to root lodging.J Agron Crop Sci,1992,168:113-118
[13]马均,马文波,田彦华,杨建昌,周开达,朱庆森.重穗型水稻植株抗倒伏能力的研究.作物学报,2004,30:143-148Ma J,Ma W B,Tian Y H,Yang J C,Zhou K D,Zhu Q S.The culm lodging resistance of heavy panicle type of rice.Acta Agron Sin,2004,30:143-148(in Chinese with English abstract)
[14]吴洪恺,纪凤高,文正怀,袁彩勇,韩成虎,袁生堂.水稻栽插不同株行距配比方式初探.耕作与栽培,2000,(1):17-18Wu H K,Ji F G,Wen Z H,Yuan C Y,Han C H,Yuan S T.Appropriate plant and row spacing for rice cultivation.Tillage&Cultivation,2000,(1):17-18(in Chinese)
[15]马卉,徐红,殷育峰,刘学进,李斌.机插秧不同株行距配置生产力对比试验简报.上海农业科技,2014,(5):45-46Ma H,Xu H,Yin Y F,Liu X J,Li B.Contrast test in yield potential for mechanical planting rice under different row spacing.Shanghai Agric Sci Tech,2014,(5):45-46(in Chinese)
[16]魏珊珊,王祥宇,董树亭.株行距配置对高产夏玉米冠层结构及籽粒灌浆特性的影响.应用生态学报,2014,25:441-450Wei S S,Wang X Y,Dong S T.Effects of row spacing on canopy structure and grain-filling characteristics of high-yield summer maize.Chin J Appl Ecol,2014,25:441-450(in Chinese with English abstract)
[17]周勋波,杨国敏,孙淑娟,陈雨海.不同株行距配置对夏大豆群体结构及光截获的影响.生态学报,2010,30:691-697Zhou X B,Yang G M,Sun S J,Chen Y H.Effect of different plant-row spacing on population structure and PAR interception in summer soybean.Acta Ecol Sin,2010,30:691-697(in Chinese with English abstract)
[18]李猛,陈现平,张建,朱德慧,程备久.不同密度与行距配置对紧凑型玉米产量效应的研究.中国农学通报,2009,25(8):132-136Li M,Chen X P,Zhang J,Zhu D H,Cheng B J.Study on the yield of erectophile type maize under the different density and the row spacing.Chin Agric Sci Bull,2009,25(8):132-136(in Chinese)
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