根区温度胁迫对小麦抗氧化酶活性及根苗生长的影响

通过水培的方式研究了根区温度胁迫对小麦抗氧化酶活性及根系与幼苗生长影响.结果表明:(1)改变根区温度对小麦根系抗氧化酶活性有明显的影响,根区温度过高或过低对小麦根系POD和SOD活性都具有激活效应,但随胁迫时间的延长,胁迫对SOD活性转为抑制效应,SOD活性迅速下降,MDA含量明显增加.(2)高温胁迫主要是抑制小麦根系的生长,表现为根长、根重、根系活性吸收面积与总面积及根冠比均明显低于中温处理,而株高和地上重却略有上升.低温胁迫对小麦地上部的影响大于根系.(3)在根温胁迫逆境条件下,小麦根系不是被动忍受逆境胁迫,而是主动地通过调节根系活力、根系SOD及POD活性等生理代谢过程,以减缓逆境的伤害.

Effect of root zone temperature stress on antioxidant enzymes activity and root and seedling growth of wheat

The effects of root zone temperature stress on wheat root antioxidant enzymes activity and seedling growth were studied by water cultivation experiments.The results showed that:(1) Root zone temperature stress can stimulate POD and SOD activity,but with the extent of stress,the activity of SOD turned to restrained,and then,decreased sharply,the MDA content of root was enhanced markedly also.(2) Compared with control,the wheat seedling under high root zone temperature was slim and fragile,and its root length, root dry weight,root total absorbing area,root active absorbing area and root activity decreased sharply.The effect of low root zone temperature stress on above ground of wheat was severer than root.(3) The result also showed that wheat root were not passively tolerant to stress,but actively regulated their physiological metabolic processes,and strengthened their absorbing ability to increase water and nutrient uptake,so that root injury by the environmental stress could be reduced.