花后高温胁迫对小麦灌浆特性及产量的影响

为了解小麦灌浆特性对花后高温胁迫的响应,选用西农979、洛旱2号、西农2208、新麦11、郑麦366和兰考矮早8等6个品种,于2016-2018年以自然条件为对照(CK),分析了花后高温胁迫(搭棚增温)后小麦灌浆进程、千粒重和产量的变化。结果表明,小麦粒重主要由灌浆持续时间和灌浆速率决定,不同小麦品种对花后高温胁迫的响应模式不同。西农979、洛旱2号在高温胁迫下,灌浆快增期的平均灌浆速率有所提高,但灌浆持续时间显著降低,导致粒重显著下降,且两年度的千粒重热感指数和产量热感指数均大于1,属于不抗高温型品种;新麦11、郑麦366和兰考矮早8经高温胁迫后,灌浆持续时间变化幅度不大,平均灌浆速率分别降低了0.05、0.09和0.06g·d^-1,千粒重分别降低了2.00、1.45和1.56g,但高温胁迫下粒重与CK无显著差异,且郑麦366和兰考矮早8的千粒重热感指数和产量热感指数在两个年度均小于0.9,属于抗高温型品种。

Effect of High Temperature Stress after Anthesis on Grain Filling Characteristics and Yield

In order to investigate the response of grain filling characteristics to high temperature stress after anthesis, we screened six varieties, such as Luohan 2, Zhengmai 366, etc. We studied the effects of two treatments, high temperature stress conditions(plastic-covered tunnel) and natural conditions(CK) on the grain filling process, 1 000-grain weight and yield of different varieties of wheat in 2016-2018. The results showed that grain-weight was mainly determined by grain filling stage and grain filling rate, and the response patterns of different varieties of wheat to high temperature stress after anthesis were different. The average grain filling rate of rapid increase stage in Xinong 979 and Luohan 2 was increased slightly, but the duration was decreased significantly under the high temperature stress, which led to the grain weight decreasing obviously. Thousand-kernel weight thermal index and yield thermal index in Xinong 979 and Luohan 2 were both more than 1 based on the calculation of two years, so Xinong 979 and Luohan 2 were not heat-resistant variety. After heat-stress treatment, the grain filling duration of Xinmai 11, Zhengmai 366 and Lankao Aizao8 changed slightly. The average grain filling rate was decreased, by 0.05 g·d^-1, 0.09 g·d^-1 and 0.06 g·d^-1, respectively. The 1 000-grain weight was decreased slightly by 2.00 g, 1.45 g and 1.56 g, respectively.1 000-kernel weight thermal index and yield thermal index of Zhengmai 366 and Lankao Aizao8 were lower than 0.9, suggesting that the two varieties were heat-resistant wheat germplasm.