不同玉米品种抗旱性的生理鉴定与综合评价

Physiological Identification and Comprehensive Evaluationof Drought Resistance of Different Maize Varieties

在新疆吐鲁番地区以42个玉米主栽品种为材料,设置正常灌溉、中度干旱和重度干旱处理,测定玉米灌浆期穗位叶叶绿素(Chl)、丙二醛(MDA)和脯氨酸(Pro)含量,超氧化物歧化酶(SOD)、过氧化氢酶(CAT)和过氧化物酶(POD)活性以及籽粒产量。采用灰色关联度分析、抗旱指数(DI)、抗旱性度量值(D值)、加权抗旱指数(WDI)和聚类分析相结合的方法,筛选与抗旱紧密相关的生理指标,并进行综合评价。结果表明,中度干旱胁迫下,上述6个生理指标与综合抗旱指数(CDI)的关联度依次为SOD(0.803)、Ch(l 0.796)、MDA(0.788)、CAT(0.770)、Pro(0.756)、POD(0.755);重度干旱胁迫下,这6个生理指标与CDI的关联度依次为SOD(0.725)、MDA(0.724)、Chl(0.718)、Pro(0.692)、CAT(0.681)、POD(0.667)。基于D值和WDI值的42个玉米品种抗旱性评价结果存在一定差异,但不同品种抗旱性排序基本一致。相关性分析表明,产量DI与综合抗旱性度量值(CD)和综合加权抗旱指数(CWDI)均呈显著正相关。根据CWDI将42个玉米品种抗旱性分为高抗、中抗、低抗,其中高抗品种2个,中抗品种13个,低抗品种27个。方差分析表明,高抗玉米组产量DI显著高于中抗和低抗。综上,以上玉米灌浆期穗位叶片6个生理指标可作为玉米品种抗旱性生理鉴定的参考指标,42个参试品种中辽单145和锦华150具有较强抗旱性。

A total of 42 maize cultivars were selected as the test materials and treated with normal irrigation,moderate and severe drought stress in the experimental base of Turpan Institute of Agricultural Sciences,Xinjiang Academy of Agricultural Sciences.The changes of chlorophyll(Chl)content,malondialdehyde(MDA)content,proline(Pro)content,the activities of superoxide dismutase(SOD),catalase(CAT)and peroxidase(POD)in ear leaf of maize at grain filling stage,and also grain yield were measured.The grey correlationanalysis,drought resistance index(DI),drought resistance evaluation values(D-value),weighted drought resistance index(WDI-value)and cluster analysis were used to screen physiological indexes closely relatedtodrought resistance,and the drought resistance of different maize varieties was evaluated comprehensively.Theresults showed that the correlation degree between the six physiological indexes and the comprehensive drought resistance index(CDI)under moderate drought stress were SOD(0.803),Chl(0.796),MDA(0.788),CAT(0.770),proline(0.756)and POD(0.755);Under severe drought stress,the correlation degree between the sixphysiological indexes and the CDI were SOD(0.725),MDA(0.724),Chl(0.718),proline(0.692),CAT(0.681)and POD(0.667).Based on the D value and WDI value,the drought resistance evaluation results of the twomethods had some differences,but the drought resistance ranking of different varieties was basically the same.The correlation analysis of average DI of yield and values of(CD)and(CWDI)were positively correlated.According to the CWDI value,the 42 maize varieties were divided into high drought resistance,mediumdrought resistance,and low drought resistance,among which included two high drought resistant varieties,and13medium drought resistant varieties,27 low drought resistant varieties.Variance analysis showed that the DI of yield of high resistance maize group was significantly higher than that of medium resistance and lowresistance.In conclusion,the above six physiological indexes of maize leaves combined can be used as reference indexes for physiological identification of drought resistance of maize varieties at the grain filling stage.Liaodan 145andJinhua 150 have strong drought resistance among 42 tested varieties.