橡胶树低温伤害的生理反应

在人工零上低温下,巴西橡胶树(Hevea brasiliensis)叶质膜透性随低温处理时间的延长而持续上升,抗冷品系的上升速率比不抗冷品系慢。呼吸强度和ATP含量均随处理时间的延长而持续下降,抗冷品系下降速率比不抗冷品系慢。叶绿体Mg~(++)—ATPase活性也表现出明显抗性差异。可见,低温下叶组织的质膜透性、呼吸强度、ATP含量以及Mg~(++)—ATPase活性的变化与品系抗冷性有关。低温下呼吸强度、ATP含量与质膜透性变化呈负相关,质膜透性的变化与供能有关。

PHYSIOLOGICAL RESPONSES OF HEVEA BRASILIENSIS DURING THE CHILLING INJURY

Under the refrigerating conditions ( low temperatures of above oC ) , the permeability of plasma membrane in Hevea brasiliensis was rising steadily with the prolongation of low temperature treatment, and the rising rates of chilling resistant clones were slower than those of chilling-sensitive clones, The respiratory intensity and ATP content were dropping with the prolongation of treatment time, and the dropping rates of chilling resistant clones were slower than those of chilling sensitive clones.The resistant clones alones also displayed a noticeable change in the activities of chloroplasts Mg ++-ATPase, obviously different from those of the sensitive clones. It is thus seen that the changes of the permeability of plasma membrane, respiratory intensity, ATP content and Mg++-ATPase activity are related to the chilling resistance of clones. The respiratory intensity and ATP content under low temperature negatively related to .the change of plasma membrane permeability which has a bearing on the supply of energy.