August 7th is Liqiu, and the farmer said, "In autumn, we must plant cabbage, we must pick off fresh cotton during the summer heat," and "vegetate the head with radish." We can see that the autumn season is a season suitable for planting Chinese cabbage. Taking into account the fertilization status of Chinese cabbage in recent years, it can be clear that there are several principles to be grasped this year.
The first principle is that the application of nitrogen fertilizer should be appropriate. Practice has proved that the production of 1000 kilograms of fresh vegetables needs to absorb about 2.0 kilograms of pure nitrogen from the soil. The production of 10,000 kilograms of fresh vegetables requires a total absorption of 22-25 kilograms of nitrogen. The nitrogen needed for Chinese cabbage can come from soil, organic fertilizer and fertilizer respectively. . Under the conditions of applying a large amount of organic fertilizer, the application amount of chemical nitrogen fertilizer should be appropriately reduced. In addition to the appropriate amount, the use of nitrogen fertilizer is also important. During the entire growth period of Chinese cabbage, the amount of nitrogen absorption at different stages is different. The seedling period is very small, accounting for about 2% of the total. The rosette period increased to about 28%, and the nitrogen uptake during the core period was the highest, accounting for about 70% of the total. Therefore, the nitrogen fertilizer should be applied in divided doses, light and heavy. The growth period of Chinese cabbage is long and it is necessary to apply basal fertilizer. In old vegetable fields, the soil fertility is high, and organic fertilizer can be applied in an appropriate amount. The nutrient composition of chemical compound fertilizer is mainly phosphorus and potassium. In the new vegetable land, it is necessary to re-apply organic fertilizer and apply ternary compound fertilizer. Pay attention to the application of organic fertilizer and potash fertilizer. In the top-dressing application, Chinese cabbage must control water-control fertilizers (mainly nitrogen-controlling) from the seedling stage to the rehabilitative planting stage. In addition to the special circumstances, it is necessary to raise the seedlings, but it is generally necessary to plant seedlings during the rosette period. The first time the topdressing fertilizer is in the key stage of the rosette period, it is advisable to chase the short-acting nitrogen and potash fertilizers, and at the same time, water and fertilizers enter the heart-filling period. The second top dressing of Chinese cabbage is in the early and middle period of Baoxin. The main topdressing nitrogen fertilizer is up to two times and the amount of nitrogen is controlled. In the later period of time, nitrogen fertilizer was stopped.
The second principle is to increase the application rate of phosphorus and potassium fertilizers. The increase of potassium fertilizer in basal fertilizer and top dressing is beneficial to the cabbage's core and disease resistance. Pay attention to the application of potash fertilizer in the top-dressing of the pre-brain. If the supply of phosphorus and potassium fertilizer is insufficient during the period of the cabbage package, it will be difficult for the cabbage. At present, potassium fertilizer is often neglected in vegetable production. The appropriate amount of potassium is generally 12 kg per mu of potassium chloride or 16 kg of potassium sulfide. The best method of application is to divide the basal and topdressing fertilizers twice. The basal fertilizer is applied to the bottom of the burrows at the time of colonization, and the topdressing is performed after the lotus seedlings are completed and the nitrogen fertilizer and irrigation are used together.
The third principle is to attach importance to the supply of calcium. The use of calcium superphosphate in the basal diet supplements calcium nutrition, which is beneficial to the prevention of the occurrence of Chinese cabbage "dry heart-burning" disease. Cabbage is a calcium-bearing crop, and calcium deficiency, especially excessive nitrogen application, can easily cause dry heart disease. Controlling nitrogen fertilizer and supplementing calcium nutrition are the core technologies for preventing Chinese cabbage "dry heart" disease. In addition to calcium-containing fertilizers, the calcium supplementation method can also adopt the method of leaf surface supplementation, spraying 0.3%-0.5% of calcium chloride or calcium nitrate.
Corn Starch,Organic Corn Starch,Corn Starch Native,Food Grade Corn Starch
SHANDONG BAISHENG BIOTECHNOLOGY COM , https://www.baishengbioproducts.com