First, fertilizer technology 1, the amount of fertilizer. In general, the production of 100 kilograms of pear fruit requires 0.47 kg of pure nitrogen, 0.23 kg of pure phosphorus, 0.48 kg of pure potassium, and the ratio of nitrogen, phosphorus, and potassium is 1:0.5:1. If calculated as per mu of 2,500 kg of pear, Mu needs nitrogen 11.75 kg, phosphorus 5.75 kg, potassium 12 kg. In practical production, the amount of fertilizer can be calculated based on the content of various effective fertilizer components. 2, fertilization time. (1) Apply within 7-10 days after harvesting to facilitate the restoration of tree vigor, promote photosynthesis, increase nutrients and the occurrence of autumn roots, etc., and use mainly fast-acting fertilizers. (2) Base-fertilizer in October-December, dominated by organic fertilizer, accounting for 40-50% of the annual fertilization amount. Autumn basal fertilization is very important. Taking nitrogen fertilizer as an example, in the middle and late stages of pear fruit enlargement, if there are too many nitrogen fertilizers, the fruit shape will be larger, but the sugar content of the fruit will decline, the flavor will become lighter and the disease will be heavier, which does not meet the requirements for high-quality cultivation. . In early June, it is the main period when Pear New Leaf begins to synthesize carbohydrates. The tree does not need too much nitrogen, but too little nitrogen is not conducive to flower bud differentiation and will affect the flowering results in the second year. It is the best solution to this contradiction. The method is to apply some organic fertilizer in autumn and winter. (3) Before and after flowering, the top dressing was used to promote the flowering results and the growth of branches and leaves. The topdressing fertilizer before flowering was mainly quick-acting nitrogen fertilizer, and the topdressing after flowering was mainly phosphorus and potassium fertilizers. (4) During the fruit enlargement period, nitrogen, phosphorus, and potassium were used in the fruit enlargement of each variety. 3, the use of trace elements. Lack of trace elements is prone to lack of hormones and should be promptly corrected. If iron deficiency is liable to cause yellow leaf disease, 0.5% ferrous sulfate solution can be sprayed 1-2 times per month during the growing season. After repeated spraying, yellow leaves can be regreened. It is also possible to apply a certain amount of ferrous sulfate in the spring. Zinc deficiency can cause lobular disease. It can spray 4-5% zinc sulfate solution before germination, and spray 0.3-0.5% zinc sulfate after germination. In addition, the spraying of 0.2-0.5% boric acid solution during flowering or after flowering can not only treat the deficiency of boron but also increase the fruit setting rate. For pear saplings, due to the undeveloped roots of the saplings, fertilization should be based on the principle of thin-fertilizers to avoid burning seedlings. At the same time increase the phosphorus and potassium fertilizers to increase tree vigor. Second, moisture management Water management should be based on soil moisture status and pear tree water requirements to determine the irrigation time and irrigation volume. The water demand before and after flowering of pear tree before flowering, the period of young fruit after flowering, the late fruit growth, the fruit harvesting, and the time before deciduous are relatively large. The expansion period of young fruit after flowering is the critical period of water requirement of pear tree. important. Irrigation in time can promote the growth of new shoots and leaves, expand the assimilation area, enhance photosynthesis, increase fruit setting rate and increase fruit, and have a good effect on flower bud differentiation at later stages. For pear saplings, because they are sensitive to changes in the natural environment and are prone to droughts and floods, it is often necessary to loosen the soil and water in drought.
Surgical Suture in medical surgery of human tissue and
ligation. Surgical suture could be divided into Absorbable suture, Non-absorbable suture.
The suture is processed by collagen or synthetic
polymers from healthy mammal and it can be absorbed in vivo mammalian tissue.