新培育玉米自交系苗期生理生化指标与其抗旱性综合评价

以73份新培育的玉米自交系和7份已知玉米抗旱自交系为材料,采用培养间自然干旱胁迫处理方法,研究相关生理生化指标与玉米抗旱性的关系。通过玉米叶片失水率(WLR)和相对含水量(RWC)的测定分析,筛选出15份自交系进行脯氨酸(Pro)含量、丙二醛(MDA)含量以及超氧化物岐化酶(SOD)、过氧化氢酶(CAT)和过氧化物酶(POD)活性共5项生理生化指标的测定,对5项指标的耐旱系数分级,对玉米自交系的抗旱性进行综合评价。结果表明,干旱胁迫下大多数自交系表现出相对含水量下降趋势,失水率、脯氨酸含量、丙二醛含量和三个抗氧化酶类活性均表现出升高趋势。筛选出高抗旱自交系4份,抗旱自交系3份,中抗旱自交系2份,敏感自交系3份,高敏自交系3份。

Comprehensive evaluation of physiological and biochemical indexes and drought resistance of new maize inbred lines during seedling stage

Seventy-three new maize inbred lines cultivated by our research group and seven known lines were culti -vated under simulated drought-stress condition in greenhouse to investigate the relationships between drought tolerance re -lated physiological and resistance and drought .Through testing and analyzing their WLR and RWC ,15 inbred lines were selected .Five physiological and biochemical indexes of these inbred lines were examined including proline content ,mal-ondialdehyde (MDA) content ,SOD activity ,CAT activity ,and POD activity .Based on the classification of five physio-logical and biochemical indexes ,drought tolerance of the inbred lines was evaluated .The results indicated that WLR , proline content ,MDA content ,SOD activity ,CAT activity and POD activity were increased ,but relative water content became decreased .The comprehensive evaluation on drought tolerance of these lines classified them into high drought tol -erance (four lines) ,drought tolerance (three lines) ,medium drought tolerance (two lines) ,drought susceptibleness (three lines) ,and high drought susceptibleness (three lines) .