天津园艺学会《大白菜干心病科研资料汇编》已经指明,大白菜干心病病因是生理性缺钙。大量土壤化验表明,许多石灰性土壤不含碳酸根, 这就是说,碳酸钙极难离解,在碱性土壤中,几乎不提供钙离子-它不是一种速效钙。因为,一切无机盐类,必须是离子态,才能进入植物根内。所以,必须给土壤施速效钙肥。有人认为,灌溉水中碳酸氢钙可以达到soppm,不需要再补充钙。但盆栽试验所甩的液体培养基,必须每天保持钙离子浓度 Tianjin Horticultural Society “Chinese cabbage dry research materials compilation” has indicated that the cause of dry cabbage is a physiological calcium deficiency. Extensive soil tests have shown that many calcareous soils contain no carbonate, which means that calcium carbonate is very hard to dissociate and provides little to no calcium ions in alkaline soils - it is not a quick-acting calcium. Because, all inorganic salts, must be ionic, in order to enter the plant roots. Therefore, we must give soil fertilization of calcium. Some people think that irrigation water, calcium bicarbonate can reach soppm, do not need to add calcium. However, the liquid culture medium in the pot experiment must maintain the calcium concentration every day