散粉前后高温胁迫对不同玉米杂交组合农艺性状及产量的影响

Effect of Pre-and Post-Anthesis High-Temperature Stress on Agronomic Traits and Yield of Different Maize Hybrid Combinations

为研究散粉前后高温胁迫对玉米生长、吐丝、散粉特性等农艺性状及产量的影响,以25个遗传背景不同的玉米高级鉴定组合为材料,通过全自动智能升温系统设置42℃高温,于散粉前10 d—散粉后10 d进行高温处理,对照全生育期无高温胁迫。结果表明,高温处理后,吐丝持续时间总体延长,较对照最多滞后达7 d,散粉持续时间总体变短,吐丝散粉间隔期总体拉长;所有组合叶片SPAD值均降低(降幅4.1%~12.9%),株高总体增加(增幅1.1%~35.4%),地上部干质量均降低(降幅10%以上),根干质量、穗位高和茎粗增减趋势不一致;产量减少1.8%~11.3%。根据耐热系数和隶属函数值,供试杂交组合22、14相对较耐热。根据主成分分析结果,吐丝持续时间、散粉持续时间、吐丝散粉间隔期、单穗粒质量、地上部干质量、根干质量、株高、茎粗、根冠比这9个指标可以作为杂交组合耐热筛选的指标。

In order to explore the effect of pre-and post-anthesis high-temperature stress on growth,silking and anthesis characteristics and yield,25 advanced cross combinations with separate genetic background were used as materials,42℃was imposed through automatic intelligent heating system from 10 d before anthesis to 10 d after anthesis,with the suitable temperature as control.The results showed that after high temperature treatment,silking duration was prolonged as much as 7 days compared with the control;the anthesis duration was shorter,and anthesis-silking interval was elongated.After high temperature treatment,the SPAD values of all cross combinations decreased by 4.1%—12.9%,plant height increased by 1.1%—35.4%,the dry weight of the shoots all decreased by more than 10%,and dry root weight,ear height and stem diameter of all cross combinations were all affected,but the change trends were inconsistent.High temperature treatment before and after anthesis reduced grain yield by 1.8%—11.3%.According to the heat resistance coefficient and membership function value,the cross combinations 22 and 14 were relatively heat resistant.According to the results of principal component analysis,9 traits including duration of silking and anthesis,silking-anthesis interval,grain yield per ear,dry shoot weight and root weight,plant height,stem diameter and root-shoot ratio could be used as indicators for heat resistance screening of hybrid combinations.