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本试验证明,在大白菜的莲座期和结球初期,水分控制时间超过17天以上,0～10厘米的土壤含水量,低于12％以下,氮肥量施用过多(每亩追肥量折合纯氮高于40斤以上)是引起大白菜干烧心病的重要环境条件,多氮区发病率较其它低氮区高4～7倍,病情指数高5～14倍。它们对大白菜贮藏期发病也有明显的影响,随贮藏时期的延长而加重。干烧心发病严重部位,与健康株相比,其同叶位的叶柄与叶片含钙比值最高,叶片中的含钙量也比正常株显著减少,而含氮量较高,Ca/N比值小。在干烧心发病地块,注意浇水,保持土壤和近地面空气湿度,适量控制氮素肥料的施用是减轻或防治干烧心病的农业措施之一。
The test proved that in the Chinese cabbage rosette and early stage of the balling, the water control time is more than 17 days, the soil water content of 0 ~ 10 cm is less than 12%, and the nitrogen fertilizer is applied too much Nitrogen higher than 40 pounds) is an important environmental condition that causes Chinese cabbage to burn heart disease. The incidence of multiple nitrogen zones is 4 to 7 times higher than that of other low nitrogen zones, and the disease index is 5 to 14 times higher. They also have a significant impact on the incidence of Chinese cabbage during storage, with the extension of the storage period aggravate. Compared with the healthy plants, the ratio of calcium in petiole and leaf at the same leaf position was the highest, while the calcium content in leaves was significantly lower than that at the normal level, while the nitrogen content was higher and the ratio of Ca / N was smaller . In the dry heartbreak plots, pay attention to watering, to maintain soil and near-surface air humidity, the amount of nitrogen fertilizer to control the application of mitigation or prevention of heart disease is one of the agricultural measures.