摘要
为探讨茉莉酸甲酯(Methyljasmonate,MeJA)对镉胁迫下小麦幼苗生长发育和镉积累的作用及可能机制,本试验采用叶面喷施激素的水培方法,分析1μmol·L^(-1)和100μmol·L^(-1)MeJA对镉胁迫下小麦幼苗生长、根系形态、光合特性及镉吸收分配的影响。结果表明,相较于清水对照,1μmol·L^(-1)MeJA可以显著提高小麦幼苗生物量15%~30%,降低小麦整株镉含量14%~43%。MeJA可提高小麦幼苗的根长、根表面积和根体积,以及净光合速率、气孔导度和蒸腾速率,但降低胞间CO_(2)浓度。除此以外,1μmol·L^(-1)MeJA可以显著降低根系离子态镉、有机酸-镉所占比例,提高果胶/蛋白质吸附镉和不溶性草酸镉所占比例。由此可见,叶面喷施MeJA可以降低小麦幼苗根系镉吸收能力,提高干物质积累,降低幼苗镉含量,促进活性态镉向惰性镉的转化,缓解镉毒害。
In order to explore the function and mechanism of methyl jasmonate(MeJA)on the growth and cadmium(Cd)accumulation of wheat seedlings under Cd stress,a hydroponic experiment with foliar spraying hormone was conducted.This experiment studied the effects of MeJA(1μmol·L^(-1) and 100μmol·L^(-1))on the dry matter accumulation,Cd concentration,root morphology,photosynthetic parameter characteristics,and Cd chemical speciation.Compared with the control group,1μmol·L^(-1) MeJA significantly increased the biomass of wheat seedlings by 15%~30%,and reduced the Cd concentration in the whole plant by 14%~43%.The treatment also increased root length,root surface area,root volume,net photosynthetic rate,stomatal conductance,and transpiration rate of the wheat seedlings,but reduced intercellular CO_(2) content.In addition,1μmol·L^(-1) MeJA significantly reduced the proportions of ionic Cd and organic acid-Cd in the roots,and increased the proportion of insoluble Cd oxalate and pectate/protein integrated Cd.It can be concluded that foliar spraying of MeJA can reduce Cd concentrations in seedlings through the inhibition of root Cd uptake ability and the enhancement of dry matter accumulation.It can also alleviate the toxicity of Cd through the improvement of transformation from active-Cd to unactive-Cd.
作者
冯文静
高巍
孙苗苗
赵鹏
康国章
刘红恩
秦世玉
李畅
睢福庆
FENG Wenjing;GAO Wei;SUN Miaomiao;ZHAO Peng;KANG Guozhang;LIU Hongen;QIN Shiyu;LI Chang;SUI Fuqing(College of Resources and Environment,Henan Agricultural University,Zhengzhou 450002,China;College of Agronomy,Henan Agricultural University,Zhengzhou 450046,China)
出处
《农业环境科学学报》
CAS
CSCD
北大核心
2022年第5期933-942,共10页
Journal of Agro-Environment Science
基金
中国博士后科学基金项目(2017M622345)
河南省科技攻关项目(192102110021)
国家自然科学基金联合基金项目(U1504313)。
关键词
重金属
镉
茉莉酸甲酯
光合作用
根系形态
镉化学形态
heavy metal
cadmium
methyl jasmonate(MeJA)
photosynthesis
root morphology
cadmium speciation
