小麦幼苗呼吸速率对水分胁迫的反应

Responses in Respiratory Rate of Wheat Seedlings on Water Stress

小麦幼苗呼吸速率在水分胁迫下发生了一系列变化.其幼叶呼吸速率在胁迫初期升高;但当RWC 降到约85%以下时,呼吸速率又下降,根的呼吸速率在胁迫时是以指数曲线形式下降.自然干旱和渗透胁迫所得结果基本一致.显然,在水分胁迫下小麦幼叶和根的呼吸速率变化模式不一样;抗旱与不抗旱品种间呼吸速率变化的幅度也有差异.

A series of changes in respiratory rate occurred in wheat seedlingsunder water stress.Respiratory rate in young leaves rose from the beginn-ing of stress,but when relative water content of the leaf was further re-duced to about 85% or less,the respiratory rate declined speedily.Res-piratory rate of wheat roots declined exponentially under stress.The chan-ges in respiratory rate of wheat under natural drought and under osmoticstress induced by PEG solution were essentially the same.It is obviousthat the changing patterns of respiratory rate in wheat young leaves androots were different under water stress.The changing scopes of respira-tory rate were different too between cultivars of drought-resistant wheatand drought-sensitive wheat.