摘要
本研究以4份青贮玉米品种为试材,在正常供水(CK)、PEG-6000模拟干旱胁迫(DS)、CK下施加1.0 mg/L的外源2,4-表油菜素内酯(EBR)(CK+EBR)、DS下施加1.0 mg/L的EBR(DS+EBR)等处理下分别测定了幼苗的生长参数及光合特性,以期探究干旱胁迫下外源EBR对青贮玉米幼苗生长及光合特性的影响及响应机制。结果表明,DS胁迫下,4份青贮玉米幼苗的SPAD值(SPAD)、RuBPCase活性(RuBPCase)、气孔导度(Gs)、蒸腾速率(Tr)、净光合速率(Pn)、苗长(SL)和苗鲜重(SFW)均明显降低,分别降低了22.82%、38.29%、35.26%、30.02%、27.92%、15.84%和25.78%,而水分利用效率(WUE)、胞间CO_(2)浓度(Ci)和气孔限制值(Ls)均明显升高,分别升高了5.16%、17.11%和16.80%;CK+EBR和DS+EBR处理下,4份青贮玉米幼苗的SPAD、RuBPCase、Gs、Tr、WUE、Pn、SL和SFW均不同程度增大,而Ci和Ls均不同程度降低。热图Hierarchical clustering聚类和主成分分析表明,青贮玉米幼苗的2个生长参数及8个光合特性与其抗旱性紧密相关,这10个性状通过彼此间的相互作用共同形成了青贮玉米品种的抗旱基础。利用抗旱指数及外源EBR干旱缓解效应系数对4份青贮玉米品种的抗旱性及外源EBR干旱缓解效应进行了综合评价,这4份青贮玉米品种的综合抗旱性介于0.300(铁研53)~0.828(西蒙707),而DS+EBR处理下,这4份青贮玉米品种的综合外源EBR干旱缓解效应介于0.187(西蒙707)~0.403(五谷丰贮1号)。因此,施加1.0 mg/L的EBR可有效缓解干旱胁迫对青贮玉米幼苗光合生理特性及幼苗生长发育的不利影响,且EBR对抗旱性弱的青贮玉米品种的干旱缓解效果明显优于抗旱性强的品种。
The four silage maize varieties as materials in this study,the growth parameters and photosynthetic characteristics of their seedlings were measured under normal(CK),PEG-6000 induced drought-stress(DS),1.0 mg/L 2,4-epibrassinolide(EBR)induction under CK(CK+EBR),and 1.0 mg/L EBR induction under DS(DS+EBR),respectively,to explore the effects of exogenous EBR on growth and photosynthetic characteristics of silage maize seedlings under drought stress and clarify their response mechanisms.It showed that,the SPAD value(SPAD),RuBPCase activity(RuBPCase),stomatal conductance(Gs),transpiration rate(Tr),net photosynthetic rate(Pn),seedling length(SL),and seedling fresh weight(SFW)of the four silage maize seedlings were significant decreased under DS,which on were decreased 22.82%,38.29%,35.26%,30.02%,27.92%,15.84%and 25.78%,respectively,however,their water use efficiency(WUE),intercellular CO_(2) concentration(Ci),and stomata limitation(Ls)were clearly increased,which on were increased 5.16%,17.11%and 16.80%,respectively;further the SPAD,RuBPCase,Gs,Tr,WUE,Pn,SL and SFW of the four seedlings were increased to varying degrees under CK+EBR and DS+EBR,however,their Ci and Ls were decreased to varying degrees.The heat map with hierarchical clustering analysis and principal component analysis indicated that the two seedling growth parameters and eight photosynthetic characteristics of silage maize were closely related to their drought resistance,and these ten traits interrelated with each other and formed the basis of drought resistance in silage maize varieties;the drought resistance index and drought mitigation effect coefficient of exogenous EBR were used to comprehensively evaluate the drought resistance and drought mitigation effect of exogenous EBR in these varieties,the comprehensive drought resistance of the four varieties were 0.300(Tieyan53)~0.828(Ximeng707),moreover,the comprehensive drought mitigation effect of exogenous EBR of these varieties were 0.187(Ximeng707)~0.403(Wugufengzhu1hao).Therefore,1.0 mg/L EBR induc
作者
赵小强
任续伟
张金乾
钟源
Zhao Xiaoqiang;Ren Xuwei;Zhang Jinqian;Zhong Yuan(Gansu Provincial Key Laboratory of Aridland Crop Science,Gansu Agricultural University,Lanzhou,730070;Agricultural Technology Center of Longxi County,Longxi,748100;College of Modern Agriculture,Tulufan Vocational Technical College,Tulufan,838000)
出处
《分子植物育种》
CAS
北大核心
2023年第10期3371-3382,共12页
Molecular Plant Breeding
基金
国家自然科学基金项目(32060486)
甘肃农业大学甘肃省干旱生境作物学重点实验室开放基金项目(GSCS-2019-8,GSCS-2020-5)
甘肃农业大学科技创新基金-公招博士科研启动基金项目(GAU-KYQD-2018-19,GAU-KYQD-2018-12)
甘肃省高等学校创新能力提升项目(2019A-052,2019A-054)共同资助。
