以30个黄淮海地区主栽玉米品种为材料,大田人工模拟增温,于播种后44 d开始进行高温处理,至吐丝后8 d结束,研究高温对不同玉米杂交种形态、叶片生理以及产量构成因素的影响,筛选出玉米杂交种花期耐热性评价指标,并在此基础上对30个玉米杂交种花期耐热性进行综合评价。结果表明,(1)高温胁迫阻碍了玉米雌雄穗的分化,造成植株生长中心转移,表现为株高显著增加、雌雄间隔期延长,且不同基因型玉米间存在显著差异。(2)高温处理后,穗位叶片变薄,其比叶重、叶绿素相对含量及净光合速率均有所下降,穗位叶片浸泡液相对电导率显著增加。(3)高温胁迫使玉米果穗行粒数明显减少、百粒重及籽粒产量显著下降。(4)综合不同品种各性状耐热系数的相关性分析及逐步回归分析结果得出,产量、百粒重、穗长、穗粗和结实率可作为评价玉米杂交种花期耐热性的主要指标。采用综合评价值进行聚类分析,将30个玉米杂交种分为耐热、中度耐热和热敏感三个类型。
英文摘要:
In order to select the heat resistance evaluation index, and evaluate the heat resistance of corn hybrid during flowering. A field experiment was carried out with 30 maize hybrids as test materials that were widely grown in Huang-Huai-Hai area. High temperature treatment was treated during flowering (from 44 d after sowed to 8 d after silking). Then the changes of different genotype maize of morphology, physiology and yield traits were studied. The results showed that:(1) High temperature stress block the ear differentiation of corn which caused the plant growth centre transfer showing up theSplant height increased and anthesis-silking interval (ASI) prolonged significantly.(2)Under heat stress, plant ear-leaf was become thinner and weight dropped significantly, the relative chlorophyll content and net photosynthetic rate decreased, while soaking liquid conductivity increased significantly.(3)High temperature stress result in the row number per ear, grain number per row and 100-grain weight decreased, and grain yield reduced significantly. (4)According to the
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