不同玉米杂交种对水分和氮胁迫的响应及其抗逆性

 【目的】研究玉米对水分胁迫和低氮条件的响应及其所受的影响，明确不同杂交种的抗旱耐瘠性表现，为干旱、半干旱和土壤贫瘠地区选用玉米品种提供依据。【方法】选择17个杂交种，设置不同水分和施氮处理的田间肥水耦合试验，研究水分和低氮胁迫对不同杂交种生长发育、形态和产量性状的影响，以产量抗逆指数对其抗旱耐瘠性进行综合评价，并选择抗逆性密切相关的8个指标对不同品种进行聚类。【结果】不同水分和低氮胁迫下玉米籽粒产量较对照明显降低，粒数减少，粒重下降，果穗变短小，秃尖增多，散粉至吐丝期间隔延迟。水分胁迫与低氮条件下受影响最大，其次是低氮胁迫。水分胁迫下增施氮肥或低氮条件下增加供水均能明显提高产量。水分与氮肥间有极显著的互作效应，这种交互作用也表现一定的复杂性，与品种密切相关。供水与不供水或施氮与不施氮以及不同品种间产量差异也均呈极显著。各胁迫处理的产量、行粒数、千粒重、秃尖长、穗粗、穗长、ASI与产量抗逆指数之间有较密切关系，平均ARI与胁迫下的产量也均呈极显著正相关，以此为评价依据并结合聚类分析表明：抗旱耐瘠性表现最好的是黔2599、黔玉3号和中单2号，其次是兴黄单89-2、黔2411、遵玉3号、贵毕302和贵毕303；而安单136表现最差，其次是黔玉1号和黔兴4号。【结论】玉米对低氮胁迫的响应要高于对水分胁迫的响应，而不同品种因抗逆性差异，对水分和低氮胁迫响应的敏感性明显不同。水分与氮肥之间有明显的协同作用。以产量抗逆指数对不同杂交种的抗逆性进行综合评价是合理的。

Response on Water Stress and Low Nitrogen in Different Maize Hybrid Varieties and Evaluation for their Adversity-resistance

ObjectiveIn order to provide the basis used in choosing maize varieties in arid,sub-arid and barren soil area,the adversity-resistance of different hybrid varieties under water stress and low nitrogen were studied in this paper.MethodSeventeen hybrid varieties were cultivated in fields with different water and nitrogen treatments to study the effects of water and nitrogen stress on them. The drought resistance and barren tolerance of these varieties were comprehensively evaluated based on adversity resistance index of yield (ARI) ,and eight indexes closely correlated to adversity-resistance were selected to cluster analysis.ResultThe results showed that the yields of hybrid varieties under water stress and low nitrogen declined obviously comparing with contrast,grain number per ear reduced,grain weight descended,ear became shorter and smaller,barren ear tip increased,anthesis and silking interval (ASI) delayed. The effects of WNT treatment on growth and development,morphological traits,yields and their components were more than of NT and WT treatment. To supply nitrogen under water stress or water under low nitrogen leaded to increase yield obviously,the interaction between water and nitrogen was significant,and correlated to maize varieties. The differences in yield between water stress and normal water,low nitrogen and normal nitrogen,or among these varieties were significant at 0.01 probability level. There were relative affinities between ARI and tested traits under different stress treatments,and the correlations between average ARI and yields under stress condition were also significant at 0.01 probability level. The drought resistance andbarren tolerance of Qian 2599,Qianyu 3 and Zhongdan 2 were the best among these varieties,however,Andan 136,Qianyu 1 and Qianxing 4 were the worst.ConclusionThe response of low nitrogen on maize were more sensitive than of water stress,and sensitivities of different hybrid varieties to water and nitrogen stress were obviously different because of the diversity of drought resistance and barren tolerance. It is reasonable to evaluate synthetically the adversity-resistance with ARI in maize.