2013年、2016年分别以40个杂交中稻品种为材料，在人工气候室和自然高温条件下鉴定了不同品种开花期的耐高温性。结果表明，人工气候室模拟高温下鉴定耐高温指数≥0.5的品种，两种条件下的耐高温指数呈极显著正相关；而人工气候室模拟高温下鉴定的耐高温指数≤0.49的品种，两种条件下的耐高温指数的相关性不显著，原因在于部分在人工气候室模拟高温下鉴定的不耐高温品种在自然条件下因花时早而避开了高温伤害，仍表现出较高的耐高温指数。根据开花期耐高温性可以把杂交水稻分为耐避双重型、耐高温型、避高温型和高温敏感型4种类型。

An experiment was conducted to determine the effects of extreme high temperature on high temperature resistance of mid-season hybrid rice at flowering period by applying different sowing dates and intelligent artificial climate chamber in 2013 and 2016, using forty hybrid rice cultivars as materials. The results showed that there were very significant positive correlation between the high temperature resistances under intelligent artificial climate chamber condition and those under natural high temperature condition with varieties of high temperature index over 0.5, but no significant correlation of these varieties of high temperature index below 0.5. The reason is that some varieties with no high temperature resistant in artificial climate chamber still showed a good high temperature resistance under natural high temperature condition, because of flower early and avoid the high temperature damage. According to the characteristics of high temperature resistance at flowering period, hybrid rice were divided into 4 types: both of resistance and avoid high temperature type, resistance to high temperature type, avoid high temperature type and high temperature sensitive type.