镉胁迫对10个桑树品种种子萌发的影响
|
摘要
【目的】了解不同桑树品种种子萌发期的耐镉性,为筛选耐镉桑树品种及其推广应用提供参考依据。【方法】以10个桑树品种种子为试验材料,设镉浓度(按Cd~(2+)计)为5.0、30.0、50.0和100.0 mg/L的胁迫处理进行发芽试验,以不添加镉为对照(CK),测定各处理桑树种子萌发期的萌发率、萌发指数、活力指数、幼根长及胚轴长等指标,采用隶属函数法对不同桑树品种种子的耐镉性进行聚类分析。【结果】随镉浓度的提高,10个桑树品种种子的萌发率、萌发指数及活力指数均呈下降趋势,镉浓度越高下降越明显,在高浓度(50.0和100.0 mg/L)处理下均显著低于CK(P<0.05),其中活力指数降低最明显;镉对桑树种子幼根和胚轴生长具有明显的抑制作用,且对幼根的抑制作用大于胚轴;供试10个桑树品种种子对镉的耐受能力存在差异,根据隶属函数综合值进行聚类分析,可将10个桑树品种种子分为镉敏感型、中间型和镉耐受型三大类,其中桂桑6号和粤桑11号种子的耐镉性最强,属于镉耐受型品种;69851、桂桑优12号、蛋白桑、桑特优2号、桂桑优62号、桂桑5号和粤桑51号种子的耐镉性居中,属于中间型品种;沙2×伦109种子的耐镉性较弱,属于镉敏感型品种。【结论】桂桑6号和粤桑11号种子的耐镉性较强,可作为修复镉污染土壤优先选择的桑树品种推广种植。
【Objective】The cadmium(Cd)tolerance of different cultivars of mulberry seeds during the germination period was explored to provide reference for screening mulberry cultivars with strong cadmium tolerance and their application.【Method】The seeds of ten mulberry cultivars were used as experimental materials. Germination rate,germination index,vigor index,radical length and hypocotyl length of mulberry seeds during germination stage were determined under cadmium stress with different cadmium concentrations(5.0,30.0,50.0 and 100.0 mg/L)which was calculated with Cd~(2+).No cadmium treatment was as control(CK). Membership function method was used in cluster analysis of cadmium resistance of ten mulberry cultivars seeds.【Result】The results showed that the germination rate,germination index,and vigor index of ten mulberry seeds decreased with increasing of cadmium concentration. The higher the concentration,the more obvious inhibition was observed. All the parameters in the treatment with high cadmium concentrations(50.0 and 100.0 mg/L)were significantly lower than those of control(P<0.05). The inhibition to the vigor index was the greatest. The growth of radicle and hypocotyl were also inhibited by cadmium,and the inhibition of radicle was greater than that of hypocotyl. Ten mulberry cultivars had different resistances to cadmium stress. The cluster analysis of the membership function integrated values showed that the ten varieties were divided into three categories with high,medium and low resistance to cadmium stress. Both Guisang 6 and Yuesang 11 had the highest resistance to cadmium stress(high resistance),69851,Guisangyou 12,Danbaisang,Sangteyou 2,Guisangyou 62,Guisang 5 and Yuesang 51 were middle resistant(medium resistance),Sha 2×Lun 109 had low resistant to cadmium stress(cadmium sensitive).【Conclusion】The seeds of Guisang 6 and Yuesang11 have high cadmium resistance,and them can be used as priority to grow on cadmium-contaminated soil.
【Objective】The cadmium(Cd)tolerance of different cultivars of mulberry seeds during the germination period was explored to provide reference for screening mulberry cultivars with strong cadmium tolerance and their application.【Method】The seeds of ten mulberry cultivars were used as experimental materials. Germination rate,germination index,vigor index,radical length and hypocotyl length of mulberry seeds during germination stage were determined under cadmium stress with different cadmium concentrations(5.0,30.0,50.0 and 100.0 mg/L)which was calculated with Cd~(2+).No cadmium treatment was as control(CK). Membership function method was used in cluster analysis of cadmium resistance of ten mulberry cultivars seeds.【Result】The results showed that the germination rate,germination index,and vigor index of ten mulberry seeds decreased with increasing of cadmium concentration. The higher the concentration,the more obvious inhibition was observed. All the parameters in the treatment with high cadmium concentrations(50.0 and 100.0 mg/L)were significantly lower than those of control(P<0.05). The inhibition to the vigor index was the greatest. The growth of radicle and hypocotyl were also inhibited by cadmium,and the inhibition of radicle was greater than that of hypocotyl. Ten mulberry cultivars had different resistances to cadmium stress. The cluster analysis of the membership function integrated values showed that the ten varieties were divided into three categories with high,medium and low resistance to cadmium stress. Both Guisang 6 and Yuesang 11 had the highest resistance to cadmium stress(high resistance),69851,Guisangyou 12,Danbaisang,Sangteyou 2,Guisangyou 62,Guisang 5 and Yuesang 51 were middle resistant(medium resistance),Sha 2×Lun 109 had low resistant to cadmium stress(cadmium sensitive).【Conclusion】The seeds of Guisang 6 and Yuesang11 have high cadmium resistance,and them can be used as priority to grow on cadmium-contaminated soil.
引文
丁继军,潘远智,刘柿良,何杨,王力,李丽.2013.土壤重金属镉胁迫对石竹幼苗生长的影响及其机理[J].草业学报,22(6):77-85.[Ding J J,Pan Y Z,Liu S L,He Y,Wang L,Li L.2013.Effect and mechanisms of cadmium stress on Dianthus chinensis seedling growth[J].Acta Prataculturae Sinica,22(6):77-85.]
付世景,宗良纲,张丽娜,孙静克.2007.镉、铅对板蓝根种子发芽及抗氧化系统的影响[J].种子,26(3):14-17.[Fu S J,Zong L G,Zhang L N,Sun J K.2007.Influence of Cd,Pb on germination and antioxidant system of Rodix isatidis[J].Seed,26(3):14-17.]
郭媛,邱财生,龙松华,邓欣,郝冬梅,王玉富.2015.镉胁迫对不同地区亚麻主栽品种种子萌发的影响[J].作物杂志,32(4):146-151.[Guo Y,Qiu C S,Long S H,Deng X,Hao D M,Wang Y F.2015.Effects of cadmium stress on seed germination of main cultivars of flax(Linum usitatissimum L.)from different regions[J].Crops,32(4):146-151.]
韩世玉.2007.桑树的生态价值及其在贵州“东桑西移”中的生态栽培[J].贵州农业科学,35(5):140-142.[Han S Y.2007.The ecological value of mulberry and its ecological cultivation models for planting mulberry from eastern to western areas in Guizhou[J].Guizhou Agricultural Sciences,35(5):140-142.]
李兰平,李正文,杨海霞.周琼,周瑞阳,李志刚.2012.铅、镉对红麻种子萌发生长的影响[J].南方农业学报,43(9):1291-1296.[Li L P,Li Z W,Yang H X,Zhou Q,Zhou RY,Li Z G.2012.Effects of lead and cadmium on seed germination and growth of kenaf(Hibiscus cannabinus L.)[J].Journal of Southern Agriculture,43(9):1291-1296.]
李林芝,韩国君,张喜定.2015.镉对柠条种子萌发及幼苗生长的影响[J].草原与草坪,35(4):61-65.[Li L Z,Han G J,Zhang X D.2015.Effect of cadmium stress on seed germination and seedling growth of Caragana korshinshii[J].Grassland and Turf,35(4):61-65.]
李仕友,熊凡,欧阳成炜,曾涛涛,李利成,谢水波.2017.万年青在镉铀胁迫下的富集特征和生理生化机制[J].安全域环境学报,17(6):2432-2437.[Li S Y,Xiong F,Ouyang C W,Zeng T T,Li L C,Xie S B.2017.Accumulation features and the physiologic-biochemical mechanism for Cd and U toxic tolerability in Rohdea japonica[J].Journal of Safety and Environment,17(6):2432-2437.]
刘发欣,高怀友,伍钧.2006.镉的食物链迁移及其污染防治对策研究[J].农业环境科学学报,25(S):805-809.[Liu F X,Gao H Y,Wu J.2006.Transfer of cadmium in food chain and its prevention and control from pollution[J].Journal of Agro-Environment Science,25(S):805-809.]
刘芸.2011.桑树在三峡库区植被恢复中的应用前景[J].蚕业科学,37(1):93-97.[Liu Y.2011.Application prospect of mulberry plants to vegetation restoration in Three Gorges Reservoir Area[J].Science of Sericulture,37(1):93-97.]
卢红玲,肖光辉,刘青山,彭新德.2014.土壤镉污染现状及其治理措施研究进展[J].南方农业学报,45(11):1986-1993.[Lu H L,Xiao G H,Liu Q S,Peng X D.2014.Advances in soil Cd pollution and solution measures[J].Journal of Southern Agriculture,45(11):1986-1993.]
曲凯丽,张艺馨,朱宏.2014.镉胁迫对小麦种子萌发的影响[J].哈尔滨师范大学自然科学学报,30(6):94-98.[Qu K L,Zhang Y X,Zhu H.2014.The effects of cadmium stress on wheat germination[J].Natural Sciences Jouranl of Harbin Normal University,30(6):94-98.]
孙亚莉,刘红梅,徐庆国.2017.镉胁迫对不同水稻品种种子萌发特性的影响[J].中国水稻科学,31(4):425-431.[Sun Y L,Liu H M,Xu G Q.2017.Effects of cadmium stress on rice seed germination characteristics[J].Chinese Journal of Rice Science,31(4):425-431.]
田丹,任艳芳,王艳玲,林肖,杨波,何俊瑜.2018.镉胁迫对生菜种子萌发及幼苗抗氧化酶系统的影响[J].北方园艺,(2):15-21.[Tian D,Ren Y F,Wang Y L,Lin X,Yang B,He J Y.2018.Effect of cadmium stress on seed germination,seedling growth and antioxidant enzyme system of lettuce[J].Northern Horticulture,(2):15-21.]
夏芳,康海岐,侯勇,徐莺.2018.重金属镉对8个水稻(Oryza sativa L)品种(系)萌发和出芽生长的影响[J].四川大学学报(自然科学版),55(2):407-413.[Xia F,Kang H Q,Hou Y,Xu Y.2018.The effect of heavy metal cadmium on germination and pot-germination growth of eight rice varieties[J].Journal of Sichuan University(Natural Science Edition),55(2):407-413.]
王新新,吴亮,朱生凤,赵林,安伟,陈宇.2013.镉胁迫对碱蓬种子萌发及幼苗生长的影响[J].农业环境科学学报,32(2):238-243.[Wang X X,Wu L,Zhu S F,Zhao L,An W,Chen Y.2013.Effects of cadmium stress on seed germination and seedling growth of Suaeda glauca[J].Journal of Agro-Environment Science,32(2):238-243.]
薛永,王苑螈,姚泉洪,宋科,郑宪清,杨建军.2014.植物对土壤重金属镉抗性的研究进展[J].生态环境学报,23(3):528-534.[Xue Y,Wang Y Y,Yao Q H,Song K,Zheng X Q,Yang J J.2014.Research progress of plants resistance to heavy metal Cd in soil[J].Ecology and Environmental Sciences,23(3):528-534.]
闫华晓,赵辉,高登征,杨玲玉,王宪泽.2007.镉离子对玉米种子萌发和生长影响的初步研究[J].作物杂志,(5):25-28.[Yan H X,Zhao H,Gao D Z,Yang L Y,Wang X Z.2007.Preliminary study on the effect of cadmium on the germination and growth of maize seeds[J].Corps,(5):25-28.]
杨翠凤,滕峥,李荣峰,曾小飚,贾桂康.2018.向日葵对重金属胁迫的防御机制及其土壤修复效率提高途径[J].河南农业科学,47(4):1-7.[Yang C F,Teng Z,Li R F,Zeng X B,Jia G K.2018.Defense mechanism of sunflower against heavy metal stress and ways to improve its soil remediation efficiency[J].Journal of Henan Agricultural Sciences,47(4):1-7.]
应金耀,徐颖菲,杨良觎,谢国雄,章明奎.2018.施用锌肥对水稻吸收不同污染水平土壤中镉的影响[J].江西农业学报,30(7):51-55.[Ying J Y,Xu Y F,Yang L Y,Xie G X,Zhang M K.2018.Effect of zinc fertilizer application on cadmium uptake by rice plants grown in soils polluted by different levels of cadmium[J].Acta Agriculturae Jiangxi,30(7):51-55.]
张桂玲.2015.重金属污水对不同湿地植物种子萌发的影响[J].中国农业大学学报,20(2):167-178.[Zhang G L.2015.Influence of heavy metal waste water on seed germination of different wetland plants[J].Journal of China Agricultural University,20(2):167-178.]
朱守晶史文娟揭雨成.2018.不同苎麻品种对土壤中镉、铅富集的差异[J].江苏农业学报,34(2):320-326.[Zhu S J,Shi W J,Jie Y C.2018.Variety difference in cadmium and lead accumulation by ramie(Boehmeria nivea)from soil[J].Jiangsu Journal of Agricultural Sciences,34(2):320-326.]
Chen Y,He Y,Luo Y,Yu Y,Lin Q,Wong M H.2003.Physiological mechanism of plant roots exposed to cadmium[J].Chemosphere,50(6):789-793.
Dukic M,Dunisijevic-Bojovic D,Samuilov S.2014.The influence of cadmium and lead on Ulmus pumila L.seed germination and early seedling growth[J].Archives of Biological Science,66(1):253-259.
Fang Z G,Hu Z Y,Zhao H H,Yang L,Ding C L,Luo L Q,Cai Q S.2017.Screening for cadmium tolerance of 21cultivars from Italian ryegrass(Lolium multiflorum Lam)during germination[J].Japanese Society of Grassland Science,63(1):36-45.
Grant C A,Clarke J M,Duguid S,Chaney R L.2008.Selection and breeding of plant cultivars to minimize cadmium accumulation[J].Science of the Total Environment,390(2-3):301-310.
Hazrat A,Ezzat K B,Muhammad A S.2013.Phytoremediation of heavy metals-concepts and applications[J].Chemosphere,91:869-881.
Jun R,Ling T,Guang H Z.2009.Effects of chromium on seed germination,root elongation and coleoptiles growth in six pulses[J].International Journal of Environmental Science and Technology,6(4):571-578.
Munzuroglu O,Geckil H.2002.Effects of metals on seed germination,root elongation,and coleoptile and hypocotyls growth in Triticum aestivum and Cucumis sativus[J].Archives of Environmental Contamination and Toxicology,43(2):203-213.
Muhammad S,Muhammad Z I.2005.The toxicity effects of heavy metals on germination and seedling growth of Cassia siamea Lamk[J].Journal of New Seeds,7(4):95-105.
Tao L,Guo M Y,Ren J.2015.Effects of cadmium on seed germination,coleoptile growth,and root elongation of six pulses[J].Polish Journal of Environmental Studies,24(1):295-299.
Wang K R,Gong H,Wang Y.2004.Toxic effects of cadmium on Morus alba L.and Bombyx moril L.[J].Plant and Soil,261(1-2):171-180.
Zhou L Y,Zhao Y,Wang S F.2015.Cadmium transfer and detoxification mechanisms in a soil-mulberry-silkworm system:Phytoremediation potential[J].Environmental Science Pollution Research International,22(22):18031-18039.
付世景,宗良纲,张丽娜,孙静克.2007.镉、铅对板蓝根种子发芽及抗氧化系统的影响[J].种子,26(3):14-17.[Fu S J,Zong L G,Zhang L N,Sun J K.2007.Influence of Cd,Pb on germination and antioxidant system of Rodix isatidis[J].Seed,26(3):14-17.]
郭媛,邱财生,龙松华,邓欣,郝冬梅,王玉富.2015.镉胁迫对不同地区亚麻主栽品种种子萌发的影响[J].作物杂志,32(4):146-151.[Guo Y,Qiu C S,Long S H,Deng X,Hao D M,Wang Y F.2015.Effects of cadmium stress on seed germination of main cultivars of flax(Linum usitatissimum L.)from different regions[J].Crops,32(4):146-151.]
韩世玉.2007.桑树的生态价值及其在贵州“东桑西移”中的生态栽培[J].贵州农业科学,35(5):140-142.[Han S Y.2007.The ecological value of mulberry and its ecological cultivation models for planting mulberry from eastern to western areas in Guizhou[J].Guizhou Agricultural Sciences,35(5):140-142.]
李兰平,李正文,杨海霞.周琼,周瑞阳,李志刚.2012.铅、镉对红麻种子萌发生长的影响[J].南方农业学报,43(9):1291-1296.[Li L P,Li Z W,Yang H X,Zhou Q,Zhou RY,Li Z G.2012.Effects of lead and cadmium on seed germination and growth of kenaf(Hibiscus cannabinus L.)[J].Journal of Southern Agriculture,43(9):1291-1296.]
李林芝,韩国君,张喜定.2015.镉对柠条种子萌发及幼苗生长的影响[J].草原与草坪,35(4):61-65.[Li L Z,Han G J,Zhang X D.2015.Effect of cadmium stress on seed germination and seedling growth of Caragana korshinshii[J].Grassland and Turf,35(4):61-65.]
李仕友,熊凡,欧阳成炜,曾涛涛,李利成,谢水波.2017.万年青在镉铀胁迫下的富集特征和生理生化机制[J].安全域环境学报,17(6):2432-2437.[Li S Y,Xiong F,Ouyang C W,Zeng T T,Li L C,Xie S B.2017.Accumulation features and the physiologic-biochemical mechanism for Cd and U toxic tolerability in Rohdea japonica[J].Journal of Safety and Environment,17(6):2432-2437.]
刘发欣,高怀友,伍钧.2006.镉的食物链迁移及其污染防治对策研究[J].农业环境科学学报,25(S):805-809.[Liu F X,Gao H Y,Wu J.2006.Transfer of cadmium in food chain and its prevention and control from pollution[J].Journal of Agro-Environment Science,25(S):805-809.]
刘芸.2011.桑树在三峡库区植被恢复中的应用前景[J].蚕业科学,37(1):93-97.[Liu Y.2011.Application prospect of mulberry plants to vegetation restoration in Three Gorges Reservoir Area[J].Science of Sericulture,37(1):93-97.]
卢红玲,肖光辉,刘青山,彭新德.2014.土壤镉污染现状及其治理措施研究进展[J].南方农业学报,45(11):1986-1993.[Lu H L,Xiao G H,Liu Q S,Peng X D.2014.Advances in soil Cd pollution and solution measures[J].Journal of Southern Agriculture,45(11):1986-1993.]
曲凯丽,张艺馨,朱宏.2014.镉胁迫对小麦种子萌发的影响[J].哈尔滨师范大学自然科学学报,30(6):94-98.[Qu K L,Zhang Y X,Zhu H.2014.The effects of cadmium stress on wheat germination[J].Natural Sciences Jouranl of Harbin Normal University,30(6):94-98.]
孙亚莉,刘红梅,徐庆国.2017.镉胁迫对不同水稻品种种子萌发特性的影响[J].中国水稻科学,31(4):425-431.[Sun Y L,Liu H M,Xu G Q.2017.Effects of cadmium stress on rice seed germination characteristics[J].Chinese Journal of Rice Science,31(4):425-431.]
田丹,任艳芳,王艳玲,林肖,杨波,何俊瑜.2018.镉胁迫对生菜种子萌发及幼苗抗氧化酶系统的影响[J].北方园艺,(2):15-21.[Tian D,Ren Y F,Wang Y L,Lin X,Yang B,He J Y.2018.Effect of cadmium stress on seed germination,seedling growth and antioxidant enzyme system of lettuce[J].Northern Horticulture,(2):15-21.]
夏芳,康海岐,侯勇,徐莺.2018.重金属镉对8个水稻(Oryza sativa L)品种(系)萌发和出芽生长的影响[J].四川大学学报(自然科学版),55(2):407-413.[Xia F,Kang H Q,Hou Y,Xu Y.2018.The effect of heavy metal cadmium on germination and pot-germination growth of eight rice varieties[J].Journal of Sichuan University(Natural Science Edition),55(2):407-413.]
王新新,吴亮,朱生凤,赵林,安伟,陈宇.2013.镉胁迫对碱蓬种子萌发及幼苗生长的影响[J].农业环境科学学报,32(2):238-243.[Wang X X,Wu L,Zhu S F,Zhao L,An W,Chen Y.2013.Effects of cadmium stress on seed germination and seedling growth of Suaeda glauca[J].Journal of Agro-Environment Science,32(2):238-243.]
薛永,王苑螈,姚泉洪,宋科,郑宪清,杨建军.2014.植物对土壤重金属镉抗性的研究进展[J].生态环境学报,23(3):528-534.[Xue Y,Wang Y Y,Yao Q H,Song K,Zheng X Q,Yang J J.2014.Research progress of plants resistance to heavy metal Cd in soil[J].Ecology and Environmental Sciences,23(3):528-534.]
闫华晓,赵辉,高登征,杨玲玉,王宪泽.2007.镉离子对玉米种子萌发和生长影响的初步研究[J].作物杂志,(5):25-28.[Yan H X,Zhao H,Gao D Z,Yang L Y,Wang X Z.2007.Preliminary study on the effect of cadmium on the germination and growth of maize seeds[J].Corps,(5):25-28.]
杨翠凤,滕峥,李荣峰,曾小飚,贾桂康.2018.向日葵对重金属胁迫的防御机制及其土壤修复效率提高途径[J].河南农业科学,47(4):1-7.[Yang C F,Teng Z,Li R F,Zeng X B,Jia G K.2018.Defense mechanism of sunflower against heavy metal stress and ways to improve its soil remediation efficiency[J].Journal of Henan Agricultural Sciences,47(4):1-7.]
应金耀,徐颖菲,杨良觎,谢国雄,章明奎.2018.施用锌肥对水稻吸收不同污染水平土壤中镉的影响[J].江西农业学报,30(7):51-55.[Ying J Y,Xu Y F,Yang L Y,Xie G X,Zhang M K.2018.Effect of zinc fertilizer application on cadmium uptake by rice plants grown in soils polluted by different levels of cadmium[J].Acta Agriculturae Jiangxi,30(7):51-55.]
张桂玲.2015.重金属污水对不同湿地植物种子萌发的影响[J].中国农业大学学报,20(2):167-178.[Zhang G L.2015.Influence of heavy metal waste water on seed germination of different wetland plants[J].Journal of China Agricultural University,20(2):167-178.]
朱守晶史文娟揭雨成.2018.不同苎麻品种对土壤中镉、铅富集的差异[J].江苏农业学报,34(2):320-326.[Zhu S J,Shi W J,Jie Y C.2018.Variety difference in cadmium and lead accumulation by ramie(Boehmeria nivea)from soil[J].Jiangsu Journal of Agricultural Sciences,34(2):320-326.]
Chen Y,He Y,Luo Y,Yu Y,Lin Q,Wong M H.2003.Physiological mechanism of plant roots exposed to cadmium[J].Chemosphere,50(6):789-793.
Dukic M,Dunisijevic-Bojovic D,Samuilov S.2014.The influence of cadmium and lead on Ulmus pumila L.seed germination and early seedling growth[J].Archives of Biological Science,66(1):253-259.
Fang Z G,Hu Z Y,Zhao H H,Yang L,Ding C L,Luo L Q,Cai Q S.2017.Screening for cadmium tolerance of 21cultivars from Italian ryegrass(Lolium multiflorum Lam)during germination[J].Japanese Society of Grassland Science,63(1):36-45.
Grant C A,Clarke J M,Duguid S,Chaney R L.2008.Selection and breeding of plant cultivars to minimize cadmium accumulation[J].Science of the Total Environment,390(2-3):301-310.
Hazrat A,Ezzat K B,Muhammad A S.2013.Phytoremediation of heavy metals-concepts and applications[J].Chemosphere,91:869-881.
Jun R,Ling T,Guang H Z.2009.Effects of chromium on seed germination,root elongation and coleoptiles growth in six pulses[J].International Journal of Environmental Science and Technology,6(4):571-578.
Munzuroglu O,Geckil H.2002.Effects of metals on seed germination,root elongation,and coleoptile and hypocotyls growth in Triticum aestivum and Cucumis sativus[J].Archives of Environmental Contamination and Toxicology,43(2):203-213.
Muhammad S,Muhammad Z I.2005.The toxicity effects of heavy metals on germination and seedling growth of Cassia siamea Lamk[J].Journal of New Seeds,7(4):95-105.
Tao L,Guo M Y,Ren J.2015.Effects of cadmium on seed germination,coleoptile growth,and root elongation of six pulses[J].Polish Journal of Environmental Studies,24(1):295-299.
Wang K R,Gong H,Wang Y.2004.Toxic effects of cadmium on Morus alba L.and Bombyx moril L.[J].Plant and Soil,261(1-2):171-180.
Zhou L Y,Zhao Y,Wang S F.2015.Cadmium transfer and detoxification mechanisms in a soil-mulberry-silkworm system:Phytoremediation potential[J].Environmental Science Pollution Research International,22(22):18031-18039.