干旱对桑树质膜透性脯氨酸积累的影响

在土壤干旱条件下,测定了桑叶质膜透性、游离脯氨酸含量。结果表明,桑叶质膜透性和游离脯氨酸的含量随着干旱程度的加剧而增加。且游离脯氨酸增加的幅度比质膜透性大;不同叶位的桑叶,虽然都表现出增加,但质膜透性随叶位数由上往下的递增而增加,游离脯氨酸含量则减少;桑树对干旱的反应存在着品种间的差异,在同样的旱境中,质膜透性能较好地反映桑树抗旱性强弱,可作为鉴别桑树抗旱性的指标之一,游离脯氨酸的变化与桑树抗早性的关系不很一致,但其增加的速率,可作为桑树受旱而发生变化的敏感参数。

EFFECT OF DROUGHT ON THE PERMEABILITY OF PLASMA MEMBRANE AND PROLINE ACCUMULATION OF MULBERRY TREE

In this study ,the permeability of plasma membrane and free proline content of mulberry leaves was measured under soil drought condition. The following results were made: 1. The permeability of plasma membrane and the free proline content in mulberry leaves increased with trie decrease of water in soil and the free proline increased more extent than the permeability of plasma membrane. 2. To all leaves on the stem,the permeability of plasma membrane and the free proline content increased under the drought condition, but the former increased and the latter decreased with the leaves position from up to low. 3. The changes of the permeability of plasma membrane and the free proline content were different in the varieties of mulbeery The permeability of plasma membrane was well able to present the extent of drought resistance, so could be suited for one of the criterion of mulberry drought resistance ;Change of free proline was not well in keeping with mulberry drought resistance. On the rate of its increase,it could be a sensitive paramerter under drought condition.