Restore the tree potential and strive for the management techniques of high yield longan in autumn in the following year

The proper management of longan in autumn is directly related to whether the tree potential of longan can be restored in that year and whether the yield can be high in the next year. According to the experience of fruit growers in planting longan for many years, the management techniques of longan in autumn are summarized.

Longan topdressing

First, restore the tree potential and enhance the ability to resist adversity. The nutrients of longan trees have been consumed a lot after several months of hanging fruit. In the four-month management from August to November in autumn, it is the key to the high yield of longan in the following year. Longan fertilizer should be increased before and after harvest in time to promote longan expansion, improve longan yield and quality, restore longan tree potential, enhance stress resistance, and lay the foundation for high yield of longan in the following year. According to the specific amount of fertilizer, take the yield of 100 jin of longan per tree as an example, 15 days before harvest, 2 kg of longan was applied to each plant, mainly quick-acting fertilizer, imported compound fertilizer, after rain or irrigation, and 2 kg of ternary compound fertilizer and 100 kg of human feces and urine per plant. Digging a 20-30cm ditch under the vertical line at the edge of the crown and applying post-cover soil can be combined with orchard irrigation to increase soil moisture, improve the fertilizer absorption effect of longan trees and accelerate the restoration of longan trees.

Second, the fruiting mother branches should be cultivated to lay the foundation for high yield in the following year. The best fruit-bearing mother branch of longan is the last mature autumn, so after longan picking, it is necessary to strengthen the water and fertilizer management of longan mother tree in time to promote autumn germination and cultivate autumn shoots into strong fruit-bearing mother branches. The uniformity of autumn shoot germination can be controlled by water and fertilizer.

Pruning and pruning. Longan trees with a good crown can increase longan yield per unit area, so longan trees should be pruned twice in a year, spring pruning combined with flower and fruit thinning, autumn pruning should be combined with tree crown, retracted branches that are too dominant in growth (refers to newly born trees), weak branches in the crown, stubble after fruit harvest, branches of diseases and insect pests, cross branches pruning, improving ventilation and ventilation in the crown, restoring longan tree potential. Naturally regulate the balance of endogenous hormones in longan trees to ensure the flowering rate of longan in the following year.

Fourth, pest control. The temperature is suitable in autumn, so we should pay attention to longan wood lice, fruit borer, moth and other pests. Insect pest control prescription, in the peak period of larval hatching, or the initial stage of new shoot germination, comprehensive spraying chemical control. Combined with the control of other pests, ① 20% scavenging rate 2000 times or 10% 100% can be sprayed with 2000 times liquid; ② 2.5% enemy kills 2000 times liquid spray, sprayed every 15 days until the new shoots are ripe. The diseased branches should be pruned deeply, the management of water and fertilizer should be strengthened, and the stout shoots should be cultivated.

Fifth, transform low-yield orchards. When the temperature drops in autumn and the root activity of longan increases, it is necessary to protect holes and improve soil in longan orchards with low yield and pipe loss, increase the application of organic fertilizer, improve soil structure, increase soil ventilation, water conservation, fertilizer conservation capacity and enhance soil fertility. In addition to applying sufficient nitrogen, phosphorus and potassium fertilizer, other fertilizers needed by longan should be applied, and trace elements should be sprayed outside the root to ensure the growth of longan. At the same time, it is necessary to loosen the soil, renew the longan hairy root, improve the root activity, rejuvenate the longan tree potential, cultivate strong fruiting mother branches, and lay the foundation for the next year's fruit.