由于缺钙所引起的大白菜生理性病害“干心病”是严重威协我国大白菜生产的病害。天津系滨海盐碱地,虽然土壤本身并不缺钙,但七十年代以来,由于降雨量偏少,从1971到1982十二年中,每两年就出现一个“秋吊年”,由于水源紧张,不少菜田水质不良(污水和咸水),土壤有机质下降,肥力递减等多种不利因素影响,因此十二年中就有六个干心病大发生年(详见表一) 1.无病年蹲苗期雨量比大发生年雨量多 Due to calcium deficiency caused by Chinese cabbage physiological disease “heart disease” is a serious threat to China’s cabbage production of disease. Tianjin Coastal saline-alkali soil, although the soil itself is not calcium deficiency, but since the seventies, due to the rainfall is small, from 1971 to 1982 in the twelve years, every two years there is a “autumn hanging year”, due to water stress, Many vegetable fields have poor water quality (sewage and brackish water), soil organic matter decline, fertility decline and other unfavorable factors, so there are six years of dry years in twelve years (see Table 1) 1. No disease Annual squat seedling rainfall occurs more than the annual rainfall