In autumn, the ground temperature gradually decreases, the roots of vegetables are severely aged, and the absorption of nutrients is hindered. In late autumn, the vegetables are in a period of prosperous growth and are prone to calcium deficiency. The calcium absorbed by vegetables plays a variety of roles in the plant body. Once the vegetables are deficient in calcium, metabolism in the body is hindered and various symptoms of calcium deficiency will occur, such as tomato umbilical rot, cabbage dry heart disease and so on. The general symptoms of calcium deficiency in vegetables are the growth of new parts of the plant, such as apical buds, root hairs, fertility, atrophy and death. The new leaves are stuck, and the new leaves are often coke-edged and incomplete; the top of the fruit is easily sunken and dark brown appears and is necrotic.
Calcium deficiency usually occurs in the soil itself; calcium is contained in the soil; soil salinity is high; roots are inhibited from absorbing water and nutrients; soil drought increases the concentration of soil solution and reduces root water absorption, thereby inhibiting calcium absorption; The application will inhibit calcium absorption, and the incidence of dry heart disease in Chinese cabbage will increase with the increase in the amount of nitrogen fertilizer.
In terms of prevention and control methods, it is mainly to control the amount of fertilizer, and it is not appropriate to use too much fertilizer at a time, especially with chlorinated fertilizers such as ammonium chloride and potassium chloride; timely irrigation to prevent soil drought; at the same time, foliar spray of calcium fertilizer can be Calcium nitrate was used as the spray fertilizer, with a concentration of 0.3% to 0.5%. Spraying is usually performed every 7 days or so, and spraying can be performed 2 to 3 times. Tomato should be sprayed on the upper and lower leaves of the inflorescence, 2~3, and the Chinese cabbage will spray calcium when it begins to enter the ball stage.
Types of wheelchairs
1. According to material classification, aluminum alloy, light material and steel aluminum alloy, light material and steel.
2. According to the type, it can be divided into manual Wheelchair and electric wheelchair, among which manual wheelchair can be divided into manual push and self-service type.
3. According to people's needs, it can be divided into single side wheelchair, toilet wheelchair, sports wheelchair and lying wheelchair.
4.According to whether it can be folded It can be divided into foldable and unfoldable wheelchairs.
Wheelchair
Medicare Wheelchair,Multifunction Wheelchair,Wheelchair Rehabilitation,Folding Electric Wheelchair
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