Vegetables are calcium-loving crops. When planting, people tend to pay attention to the application of nitrogen, phosphorus and potassium fertilizers. However, the application of calcium fertilizers has not been paid attention to, and the large number of facilities cultivated, it is more likely to cause calcium deficiency in the greenhouse soil.
According to the test, when producing greenhouse vegetables, the rational application of calcium fertilizer can generally increase production by 10% to 20%. The application of calcium fertilizer in vegetables can increase the calcium content in the plant, and it can maintain the appearance of bright color for a long time, and the appearance quality and internal quality are obviously improved. In addition, calcium deficiency is an important cause of many vegetables becoming sick and rot.
There are many reasons for the shortage of calcium in crops: the low content of available calcium in the soil can not meet the needs of vegetables for calcium; the high content of salt in the soil inhibits the absorption of water and calcium by the roots, especially in the red soil and yellow with strong acidity. In the loam, the absorption of calcium by vegetable roots is seriously affected; the concentration of soil solution is too high, or the presence of ammonium nitrogen is abundant, which hinders the absorption of calcium by vegetable roots; the shallow soil layer, especially the sandy soil, has poor water retention and fertilizer retention capacity. The amount of calcium lost is large; in the case of a large amount of nitrogen fertilizer, excessive nitrogen fertilizer will reduce the effectiveness of soil calcium. In addition, calcium moves slowly in plants, so the nutritional problem of calcium deficiency in vegetables has become a prominent problem in cultivation.
Generally, young leaves and young tissues and fruits are prone to calcium deficiency. The symptoms are as follows: the new parts of the plant such as the top buds, the root hair growth stagnation, atrophy and death; the new leaves are stuck, and the new leaves are often unfolded. On the side, the incompleteness; the plants are short and soft, and the internodes are shortened; the top of the fruit is prone to depression, showing dark brown necrosis; when there is severe calcium deficiency, the growth point is necrotic.
Vegetables should be supplemented with calcium fertilizer. First, it is necessary to choose a variety of calcium fertilizers. Different calcium fertilizers have different properties. The pH of the soil in the greenhouse is mostly 6.5-7.5. Basic or neutral fertilizers, such as slaked lime and calcium nitrate, should be used instead of acidic or physiological acid substances. Ordinary phosphate fertilizers such as superphosphate, calcium magnesium phosphate, and heavy superphosphate are important sources of calcium fertilizer. In addition, bone powder and grass ash all contain a certain amount of calcium, which is also a source of calcium that can not be ignored, and can be selected according to the situation. It is recommended to use calcium-containing medium-micro nutrient water-soluble fertilizer (containing not less than 120 g/L of calcium, not less than 20 g/L of magnesium, not less than 50 g/L of zinc, and not less than 3 g of boron. l), supplement the other medium and trace elements while supplementing calcium, pay attention to the use of fertilizer with low EC value (salt concentration), which is safer for crops.
The second is to determine the appropriate fertilization period. After the vegetables enter the prolonged period, the soil calcium nutrition begins to decrease, and the calcium in the leaves begins to decrease. At this time, the application of calcium fertilizer is the best period. Therefore, in the production of calcium deficiency in the early stage to prevent the growth of vegetables, base application can be used. In the sheds that have been planted for many years, 2,000 to 3,000 kilograms of decomposed organic fertilizer is applied to the acre, and 30 to 45 kilograms of superphosphate is added.
The third is to select the fertilization method. For the acidity of the open field or greenhouse vegetables, the method of re-application of the base fertilizer is adopted, that is, 100 kg of wood ash per plant or 50 kg of slaked lime is applied to adjust the pH of the soil. The specific method is to spread the organic fertilizer with slaked lime or grass ash, apply it evenly on the ground surface, and plow it into the ground. For vegetables in the growing season, especially those that enter the vigorous growth period, calcium nutrition can be supplemented by topdressing. Generally, 40-60 kg of slaked lime is used per mu, and the amount of lime in sandy soil is appropriately reduced, not only calcium, but also calcium. It is beneficial to neutralize soil acidity, increase pH value and improve soil aggregate structure. It can also remove 80 kg of slaked lime or 50 kg of grass ash, open one end of the membrane, ditch 10 cm deep, and apply fertilizer to the bottom of the ditch and water it. Cover the membrane with water after osmosis. Or deep ploughing and using the method of mulching and mulching cultivation to enhance its water retention and fertilizer retention capacity, maintain the relative stability of soil moisture, and reduce the loss of calcium. It can also be combined with disease-preventing spray to supplement calcium by foliar topdressing. The topdressing concentration is preferably 0.3% to 0.5%. Generally, 0.1% to 0.2% of calcium nitrate or 1% of superphosphate can be sprayed, sprayed once every 15 days, and even sprayed 3 to 4 times, the effect is better.
Disclaimer: Some articles on this website are transferred from the Internet. If legal rights of third parties are involved, please inform this website. phone
Active Pharmaceutical Ingredients
We are a specialized manufacturers of Active Pharmaceutical Ingredients from China; with advanced R & D and manufacturing in Medicine Raw Material. With high-quality products of Medicine Raw Material, we can be a trust suppliers / factory. As a wholesale of Guanfacine HCL, Isoniazid 99%, Deoxycholic Acid, Tetrahydrocurcumin, we have the perfect after-sales service and technical support. Look forward to your cooperation!
Guanfacine HCL,Isoniazid 99%,Deoxycholic Acid,Tetrahydrocurcumin,Medicine Raw Material
Xi'an Quanao Biotech Co., Ltd. , https://www.quanaobiotech.com