小麦品种对灌浆期水渍和高温的不同反应

用６种温湿度组合的处理研究了小麦品种对灌浆期湿热逆境反应的差异．结果表明．高温和水渍对百粒重均有显著影响，品种对湿热逆境的反应差异明显．这种差异主要是由于品种间耐湿性不同所致，并通过影响有效灌浆期持续时间得以表现．因此，通过选择在湿热条件下粒重稳定、光合器官功能期维持时间长等特性，从小麦种质资源中鉴定对高温水渍反应较不敏感的基因型是可能的．

GENOTYPIC VARIATION IN RESPONSE TO WATERLOGGING AND HIGH TEMPERATURE IN WHEAT DURING GRAIN FILLING

Varietal differences in response to high temperature and waterlogging were studied with 6 treatments of heat and wet combinations and various wheat cultivars in 1991-1993.The results showed that 100-kernel weight was depressed by both high temperature and waterlogging,but not by the interactive effects between heat and wet.Wheat cultivars differed greatly in response to heat-wet stresses,with less sensitive in land races and more sensitive in bred cultivars.Based on the results of variance analysis and measurement of root activity,these differences were mainly resulted form their dissimilarity of tolerance to watcrlogging rather than from that in heat tolerance or the interaction among cultivars,heat and wet.Results also showed that gentypic variation in responses to wet and heat stresses on 100-kernel weight was primarily caused by shortening of duration of grain filling instead of the rate of grain filling.It is suggested that it is possible to identify insensitive genotypes in response to wet-heat stresses through selection or those with plump and stable kernel weight and maintenance of long duration or green leaf areas.