小麦的高温伤害与高温适应

小麦叶片经受30分钟高温胁迫后，其电解质伤害性渗漏量（IL）随胁迫温度而增加，两者关系符合指数曲线性质，但超过某一临界温度时，曲线突然变陡，IL的温度系数（Q10）比临界温度之前增加数十倍至数百倍，该临界温度大致相当于或略高于致死温度，麦株经适当高温锻炼后，致死温度及IL达50％时的温度（IT50）均显著增高，但恢复常温后，锻炼效果逐渐解除。

HEAT INJURY AND HEAT ACCLIMATION IN WHEAT PLANTS

Injurious electrolyte leakage(IL)from wheat leaves after 30 minutes'heat stress incre- ased along with the increase of temperature.The relationship between IL and injurious tem- perature was closely fitted with an exponential curve.But when the temperature exceeded a critical point,the curve suddenly turned steep and the temperature coefficient(Q_(10))incre- ased to tens or even hundreds of times what was before.The critical temperature was largely equal to or slightly higher than the killing temperature.After adequate heat acclimation, both the killing temperature and the temperature at which the electrolyte leakage came to 50%(IT_(50))were apparently increased.After the temperature decreased to normal range, the acclimation effects were disappeared in a few days.