钙和水分在大白菜抗软腐病中的作用

THE RELATIONSHIP OF CALCIUM AND WATER CONTENTS OF CHINESE CABBAGE TO THE DEVELOPMENT OF SOFT ROT (ERWINIA CAROTOVORA)

软腐细菌Erwinia carotovora pv. carotovora在白菜上的发展决定于品种的抗病性,软腐细菌的数量、植株年龄以及白菜叶片的分布部位,不同的组织,甚至同一张叶片的不同部位抗性均有所不同。凡是水分含量多的部位软腐扩展迅速,水分少的软腐发展慢,含水量在大白菜抗软腐细菌的扩展中具有明显作用。钙素的增加与白菜的抗软腐能力成正相关,增加钙含量可显著减轻软腐病的为害与发展,控制水分,增施钙素可提高大白菜软腐病的抵抗性。

There was a direct correlation between inoculum concentration and the development of soft rot lesions on petioles of Chinese cabbage leaves. Soft rot lesions developed more rapidly on the midrid of the leaf than on the leaf blade. There were significant differences in relative susceptibility of leaves at different positions on the head. Soft rot of outer leaves was much more severe than that of the inner leaves. Leaves in which the green photosynthetic tissues were not removed lost water very rapidly and wilted quickly. If the 'green photosynthetic tissue was removed only with the midrib remained, the tissue maintained its turgidity and succulence but the soft rot developed more rapidly. In general, water content may play an important role in the development of soft rot. A number of experiments indicated that the greater the calcium content in cabbae. the more the cabbage was resistant to soft rot. Decreasing the water content and increasing the cal■iun content of cabbage may reduces soft rot severity and raise the resistance of cabbag in storage as well as in the field.