玉米自交系抗旱性评价指标体系的建立

 【目的】筛选玉米不同时期抗旱鉴定指标，建立玉米抗旱性评价体系。【方法】室内运用PEG（6000）胁迫处理，研究了种子吸水速率等7个指标与玉米抗旱性的关系;大棚内通过水分胁迫，研究了叶片相对含水量等24个指标与玉米抗旱性的关系。【结果】通过简单相关分析筛选出15% PEG溶液处理GDRI、相对发芽势，20% PEG溶液处理GDRI、相对发芽势及胁迫后苗期叶片水势、抽雄吐丝期叶片保水力、行粒数、单轴重、百粒重和对照相对值9个与抗旱系数或抗旱指数相关显著的指标。通过逐步回归分析筛选出5个指标：20% PEG溶液处理相对发芽势和胁迫后苗期叶片水势、抽雄吐丝期叶片保水力、行粒数、百粒重和对照相对值。根据逐步回归筛选出的指标和偏相关系数，建立了不同时期的抗旱评价（D值）方程和评价体系。【结论】20% PEG溶液处理相对发芽势和胁迫后苗期叶片水势、抽雄吐丝期叶片保水力、行粒数和百粒重和对照相对值可作为玉米抗旱性鉴定指标，利用这些指标建立的评价（D值）方程可对玉米抗旱性进行较好的评价。

Drought-Resistance Evaluation System of Maize Inbred

【Objective】 The present study was to choose drought-resistance indexes of maize in different growing period and establish a resistance evaluation system. 【Method】 Seven indexes were tested at seeding stage treated with different concentrations of solution PEG-6000, and twenty-four indexes were tested at growth stage treated with drought-stress and non-stress treatments in the PVC shed and drought shed.【Result】According to the results of simple relative analyses, nine indexes selected including germination drought resistance index of seed and relative germination energy under the condition of 20% PEG-6000 drought stress, GDRI and relative germination energy under the condition of 15% PEG-6000 drought stress, relative value of leaf water potential at seeding stage, leaf water conservation, kernel per row, axis weight per plant and 100-grain weight, they were correlated with drought resistance coefficient or drought resistance index at P≤0.05 and P≤0.01 level. Stepwise regression analysis was conducted between the relative value of nine indexes and drought resistance coefficient and drought resistance index. The result showed that relative germination energy under the condition of 20% PEG-6000 drought stress, relative value of leaf water potential at seeding stage, leaf water conservation, kernel per row and 100-grain weight significantly influenced the drought resistance. According to these indexes and partial relative coefficient, drought-resistance evaluation equation (D value) and evaluation system was established. 【Conclusion】 The five indexes could be selected as identification indexes for drought resistance in maize. Using D value equation to evaluate the drought resistance of maize is considered scientifically reliable.