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山东是大白菜主要产区。近年来,大白菜病害发生较重,特别是1996年7月下旬至9月下旬高温干旱,导致病害暴发流行。为夺取大白菜丰产丰收,现结合对大白菜防病高产的研究和广大菜农的丰产经验,将大白菜防病高产栽培技术介绍如下。一、明确大白菜防病高产与气候条件的关系大白菜是喜冷凉湿润的半耐寒性蔬菜,生育适温为10～25℃。全生育期积温早熟品种为1500℃,中熟品种为1600～1800℃。大白菜光合作用的最适温度是15～22℃。特别是播种出苗至五叶期,要求湿润气候,日均温超过25℃,幼苗长势减弱,气温达35℃以上时,干旱的地表最高温度可达55℃以上,这时大白菜的主根易受害。
Shandong is the main producing areas of Chinese cabbage. In recent years, Chinese cabbage disease occurred heavier, especially in late July to late September 1996, high temperature and drought, leading to disease outbreaks. In order to seize the bumper harvest of Chinese cabbage, now combined with the high yield of Chinese cabbage research and the rich experience of farmers, cabbage high disease-resistant cultivation techniques introduced below. First, a clear cabbage disease-resistant and productive climatic conditions Chinese cabbage is cold and wet half-cold vegetables, fertility temperature of 10 ~ 25 ℃. During the whole growth period, the precocious temperature-accumulated variety is 1500 ℃, while the mid-ripened variety is 1600-1800 ℃. The optimum temperature for photosynthesis of Chinese cabbage is 15 ~ 22 ℃. Especially the seedling to the five-leaf stage, requiring humid climate, the daily average temperature exceeds 25 ℃, seedling weakened, the temperature reaches 35 ℃ above, the maximum surface temperature of the drought up to 55 ℃ above, then the main root of Chinese cabbage vulnerable .