How to ensure high yield of longan adult trees

Environmental factors such as warm winter have seriously affected the yield of longan, so that the yield of Putian longan has been unsatisfactory in recent years. In order to ensure the high yield of longan adult trees, we must strictly control the "four passes". First of all, the variety clearance. The practice of agricultural technology department for many years shows that "Songfeng Ben" longan variety is the first choice for bumper years, stable yield and large fruit. It is suggested that the majority of fruit farmers can boldly graft this improved variety. The second is trimming. Pruning focuses on the "four shears": first, frequently cut off weak branches, dense branches, messy branches, shaded branches, disease and insect branches, and cultivate umbrella-shaped crowns and sturdy branches. The second is to cut off the extra ears of flowers, and when they are thinly folded before and after the Qingming Festival, they are cut off at section 1 and section 2 below the "Gourd Festival"; when Grain Rain is thinned back and forth, they can be cut off at the "Gourd Festival"; when the Beginning of Summer carries out thinning, cut it off at section 1 and section 2 above the "Gourd Festival". The third is to boldly cut off spring shoots, which is similar to cutting flowers and ears, so as to make more use of the germination of summer and autumn shoots. The fourth is to cut off the extra young branches. The two "whole buds" of summer and autumn shoots are very important, with only 1 Mel and 2 young shoots left on each branch. The purpose of this "four pruning" is to tidy up the tree shape, cultivate strong fruiting mother branches, and at the same time prevent the occurrence of diseases and insect pests. The third is fertilization. To prevent winter shoots, efforts must be made on fertilization. Adult trees only apply fertilizer three times a year, using the method of "one weight, two flat and three speeds". "one weight" is that fertilization in early spring is particularly important, and the amount of fertilizer should be sufficient and heavy. It is necessary to apply not only nitrogen fertilizer, but also phosphorus, potash and a small amount of boron fertilizer, as well as a large amount of farm fertilizer, straw and cake fertilizer, which accounts for 60% of the total annual fertilizer application. "Erping" is a shoot-promoting and strong fruit fertilizer in May. This time, it mainly applies human feces, urine or urea, plus a small amount of imported compound fertilizer and potassium chloride, so it appears balanced and uniform. This fertilizer application accounts for 30% of the total annual fertilizer application. "three-speed" is pre-harvest fertilizer, which is applied about 15 days before harvest, accounting for 10% of the total annual fertilizer application. In addition, do not apply fertilizer in winter, but also dig large holes at an appropriate time (when the winter shoot is about to germinate), which will not only prepare the conditions for the application of large fertilizer next spring, but also damage the root system and indirectly achieve the purpose of preventing and controlling the winter shoot. The fourth is the control of diseases and pests. The prevention and control of diseases and insect pests can be "indirect treatment", the cultivation of strong trees is the top priority. Once diseases and insect pests are found, the first is manual culling or removal of diseased branches and leaves to isolate the source of infection; the second is drug control, which must be eliminated in the bud. In recent years, fruit growers should pay special attention to the three major moths that harm new shoots: Spodoptera litchi, Spodoptera litchi and Spodoptera litchi. The focus of prevention is from August to September (in which the control of Spodoptera litura should be carried out about 12 days after longan blossoms). The autumn shoots and autumn shoots of Xiayan are sprayed once, and the medicine is sprayed for the second time every 7 minutes and 10 days.