水稻产量对生殖生长阶段不同时期高温的响应差异

Differential Responses of Grain Yields to High Temperature in Different Stages of Reproductive Growth in Rice

【目的】研究水稻产量对不同时期不同类型高温的响应差异,为耐热水稻品种的筛选与培育提供依据。【方法】在桶栽条件下,于人工气候室内,以耐热水稻品种Nagina 22、汕优63和热敏感品种两优培九为材料,设置三个处理时期,即穗分化期、开花期和灌浆期;四种处理温度,即白天高温、夜间高温、全天高温和适宜温度,研究水稻产量和产量构成因子对不同时期高温的响应。【结果】汕优63在三个时期均表现出较强的耐热性;Nagina 22在花期和灌浆期对高温耐性较强,但易受穗分化期高温影响;两优培九对不同时期高温均较敏感。汕优63在不同时期高温下均表现出稳定的伤流强度,而高温敏感品种两优培九的伤流强度受高温影响均显著下降。【结论】水稻对不同时期的高温耐性并不具有相关性,筛选或培育耐热品种时应考虑其对不同时期高温的综合耐受性。

【Objective】Our aim is to study the response of rice yield to different types of high temperature in different growth periods,and lays a basis for selection and breeding of heat-resistant rice varieties.【Method】Heat-tolerant rice varieties Nagina 22,Shanyou 63 and heat-sensitive varieties Liangyoupeijiu were pot-cultured at high daytime temperature,high nighttime temperature,high day-plus night-time temperature,and normal temperature during panicle initiation,flowering,and grain filling in artificial climate rooms,so as to elucidate the response of rice yield and yield components to high temperature in different growth periods.【Result】Shanyou 63 had comprehensive tolerance in the three growth stages;Nagina 22 had strong tolerance to high temperature during flowering and filling,but was susceptible to high temperature during panicle initiation;Liangyoupeijiu was sensitive to high temperature during all reproductive growth stages.Shanyou 63 showed stable root bleeding intensity at different reproductive growth stages,while the root bleeding intensity of Liangyoupeijiu decreased significantly at high temperature.【Conclusion】There is no significant correlation between high temperature tolerance of rice in different periods.Comprehensive tolerance to high temperature in different periods should be taken into consideration in selection or breeding of heat-resistant rice varieties.