Occurrence and Prevention and Cure of Dried Chinese Cabbage Heart
Micro Sagittal Saw,Orthopedic Drill,Angled Attachment Disposable Grasping Forceps CO.,Ltd , http://www.nsmedicalequipment.com
Tests have shown that Chinese cabbage dry heart is a physiological disease caused by physiological calcium deficiency in plants due to adverse environmental conditions. The typical symptoms are: the normal growth of the outer leaves, the white leaves, yellowing, and dryness of the part of the heart leaves can be seen after cutting the leaf ball. The mesophyll is dry paper, and the diseased and healthy tissues are clearly distinguished. In this paper, according to the investigation of several cabbage planting areas in Baodi District in the past two years, the main causes and prevention measures of the dry-heart burning of Chinese cabbage are summarized as follows: I. Causes 1. Soil physical and chemical properties. The high salinity of the soil in the plot is more severe, because the high salt content of the soil has an inhibitory effect on the absorption of calcium by plants. 2, climatic conditions. Precipitation during the growth period of Chinese cabbage, especially during the rosette period, not only affects the air humidity, but also affects the soil moisture content and the soil solution concentration. In the cabbage seedling stage and rosette period, the incidence of dry heartburn in drought-suffering years is heavy. . 3, fertilization. Excessive application of nitrogen fertilizer when the soil is very dry, on the one hand will increase the concentration of soil solution, on the other hand because the microbial activity in the soil is inhibited, part of the ammonium nitrogen is directly absorbed by the roots, thus affecting the plant's absorption of calcium, causing Dry heartburn. 4, varieties. According to new scientific research results, Chinese cabbage stem-dried heart disease is a quantitative trait controlled by multiple genes, and there are certain differences in disease resistance among varieties. 5, storage conditions. During the storage of Chinese cabbage, the supply of calcium sources ceases due to physiological activities, so there is a tendency to continue the disease. The temperature in the storage room is high and the ventilation conditions are not good. Second, prevention and control measures 1, select disease-resistant varieties. New varieties of Tianjin cabbage have a certain resistance to dry heartburn and can be selected as needed. 2. Planting Chinese cabbage should choose land with loose soil and well-drained land, and try not to choose low-lying saline-alkali land. 3. The water supply during the growth period of Chinese cabbage should be uniform, especially the changes in soil moisture during the rosette period. In rainy years, appropriate cultivators should be used, and the number of seedling days should be extended. In dry years, seedlings should be shortened and watered in time. 4. Never use excessive nitrogen fertilizer during the growth period of Chinese cabbage. Pay attention to the combined use of nitrogen, phosphorus, and potassium fertilizers. According to experience, nitrogen, phosphorus, and potassium fertilizers in the entire growth period of Chinese cabbage in Tianjin region are suitable for fertilization at a seedling stage of 5:1:4, a rosette stage of 4:1:3, and a balling stage of 4:2:4. Uniformly. 5. Extra-calcium supplementation is an effective and direct method. Usually from the cabbage rosette period, every 7 to 10 days, the mixture is sprayed with 0.7% calcium chloride and 50ppm naphthylacetate. When spraying, focus on the center leaf spray, generally 4-5 times to achieve 80% control effect. 6. Cabbage should be stored in a cool, well-ventilated place.