Zinc is an indispensable trace element for crop growth. Zinc deficiency causes plant dwarf, short internodes, leaf expansion and elongation are inhibited, leaflets appear, and leaf margins are distorted and wrinkled. Corn whitening seedlings, rice dead seedlings, etc. are all caused by zinc deficiency. Practice has proved that the application of zinc fertilizer on rice, corn, wheat, cotton, rapeseed, fruit trees, vegetables, soybeans, peanuts, potatoes, tobacco and other crops can promote crop growth and development, and increase yield by 10% to 30% . The application method of zinc fertilizer is introduced as follows:
As the base fertilizer, 0.5~2 kg of zinc sulfate per acre is used , and the zinc fertilizer is mixed with organic fertilizer, physiological acid fertilizer (not mixed with phosphate fertilizer) and fine soil. The ability of zinc to move in the soil is poor, and the effect of surface application is not good. It should be turned into the soil with the cultivated land, and the fertilization should be uniform. Zinc has a long-term fertilizer effect in the soil, and the base fertilizer does not have to be applied every year, and can be applied every other year.
The root of the root is treated with a solution of zinc oxide ( 0.1% to 0.2 %). The rooting time should not be too long, usually 3 minutes. If the time is too long, it will cause phytotoxicity. Alfalfa is especially suitable for rice and vegetable transplanting.
Soaking the zinc sulphate into a solution of 0.02%~0.05 %, the seed and soaking solution should be 1 : 1 , and then immersing for 6~12 hours, then remove the dry (not exposed to sunlight, should be dried). Rice soaking can be soaked for 24 hours at a concentration of 0.1 % . Peanuts, soybeans and other seeds should not be soaked, otherwise the seed coat will wrinkle and crack and affect the emergence of seedlings.
It is advisable to mix 2 to 6 grams per kg of seed dressing with zinc sulfate for seed dressing . The specific operation method is to first dissolve the zinc fertilizer with a small amount of water, and then dilute with water. When the seeds are mixed with zinc, the solution should not be too much, and finally the whole solution can be sucked up. Generally, 50 grams of water per 500 grams of seed is suitable, and peanuts and soybeans may be added as appropriate.
The topdressing fertilizer is mixed with 0.5~1 kg of zinc sulfate per acre with a certain amount of fine soil or water, and is applied to the soil during the crop growth period. Paddy fields can be mixed with fine soil and applied with water. The application should be carried out after the dew on the sunny day, otherwise the fertilizer will stick to the leaves and cause burns. After fertilization, it is necessary to fill the field water in time to prevent the outflow of fertilizer and water. Dry land is generally applied to dry manure and water manure. The top dressing of the roots is 50-100 grams of zinc sulfate per acre , dissolved in water and then 50 kg of water , and sprayed at 4 o'clock in the afternoon . The concentration and amount of zinc sprayed on the leaf surface can be increased or decreased as appropriate depending on the size of the plant. In spraying, if the concentration is too large to damage the leaves, it is best to add 0.2 % slaked lime to adjust the pH of the solution. Generally, it is sprayed once in the seedling stage, jointing stage and flowering stage of the crop. The application of zinc fertilizer should vary from place to place, depending on the crop, and should not be applied blindly.