多效唑增强早稻秧苗抗寒力的研究

本文阐述多效唑对早稻秧苗抗寒力的作用.研究结果表明,多效唑能有效地增强早稻秧苗抗寒力,其主要生理效应有以下几个方面:(1)能有效地减少在低温胁迫下早稻秧苗叶片细胞膜的透性,减轻膜和原生质体伤害;(2)增加低温胁迫下水稻叶片内脯氨酸含量,有利于增强原生质体的水合能力;(3)缓解低温胁迫下水稻秧苗叶片内叶绿素含量的降低和净光合速率的下降;(4)减轻低温胁迫后叶片枯死程度,保持叶片较高含水量;(5)经多效唑处理的秧苗在低温胁迫后的恢复时期,净同化率明显地高于对照.江西和我国南方诸省早稻育秧常会遇到寒潮低温侵袭,多效唑在早稻生产上的应用,对于增强早稻秧苗抗寒力和防止烂秧,有着重要意义.

Studies on the Effect of Paclobutrazol on Increasing Chilling Resistance of Early Rice Seedlings

This paper deals with the effect of paciobutrazol on the chilling resistance of early rice seedlings. The experimental results showed that the chilling resistance of early rice seedlings could be effectively increased by applying paclobutrazol,with the main physiological effects could be observed as follows:(l)The permeability of the cell membrance of the leaves of early rice seedlings was significantly decreased by paciobutrazol under low temperature stress and the injury of cell membrane and protoplast were reduced;(2)The free proline content in the leaves of early rice seedlings was raised by paciobutrazol under low temperature stress and the ability of hydration of protoplast was increased;(3)Decreasing in chlorophyll content and net photosynthetic rate were slowed down in the leaves of treated early rice seedlings under low temperature stress and matained more water in the treated leaves than that of the control;(4)The net assimilation rate in treated leaves was obviously higher than that of the control after the low temperature stress.Due to the early season rice growing is always encontered with attacks of cold waves in Jiangxi Province as well as in the southen part of China, it is of great significance applying paciobutrazol to early rice seedlings so as to enforce the chilling resistance and avoid seedlings injury.