How to do well the summer management of citrus in the critical period of citrus management in summer

Summer is an important period for citrus management, the fastest and best season for young trees to shoot out summer shoots, and it is also a key period for fruit trees to protect fruit and prevent diseases. At this time, citrus is in the period of fruit expansion, high temperature and rainy season, high temperature and humidity, and high incidence of citrus diseases and insect pests. Vinegar strengthens the management of citrus orchards in summer in order to ensure high quality, increase yield and increase income.

Citrus

First, apply enough fertilizer to promote trees and protect fruit. During the citrus expansion period, the root system has strong fertilizer absorption, and the application of sufficient fertilizer can promote the tree to strengthen the fruit and reduce the fruit drop. According to the age and fruit amount of each fruiting citrus tree, 20-25 kg of livestock and poultry manure, 1-15 kg of cake fertilizer and 0.5-1 kg of superphosphate or bone meal were applied. To apply available fertilizer at the right time, 25-50 kg of rotten manure, 0.5-1 kg of retting cake fertilizer and 150-250 g of urea should be applied to each plant about 15 days before sprouting. The fruiting citrus trees should be fertilized twice with 0.2% urea and 0.2% potassium hydrogen phosphate. Make up for what the new leaves are missing. In the case of high temperature and drought, spraying hormone can promote the division of citrus root cells, improve the absorptive capacity and prevent fruit drop.

Second, strengthen water pipes to resist drought and cool down. Mountain citrus orchards should renovate the drainage and irrigation system, strengthen garden walls, clean drainage ditches, prevent rainstorm erosion and protect soil and water. Do a good job of drought resistance and cooling to prevent high temperature fruit drop. When the growth of citrus is more than 35 ℃, the photosynthesis is weakened and the physiological function is blocked. Therefore, when the high temperature comes and the leaves curl, the water should be introduced into the citrus orchard in time to adjust the temperature and humidification with water. Sprinkler irrigation can be used to increase air and soil moisture. And loosen the soil by ploughing, cut off the soil capillaries and improve the ability of water and fertilizer conservation of citrus trees, so as to improve the microclimate of citrus orchards, reduce fruit drop and promote strong fruits. In the heat of summer, the ground of the orchard is covered with pre-cut grass to reduce direct sunlight, water evaporation and soil moisture on the surface, so as to protect the root group, enhance the root activity and reduce the fruit drop rate.

Third, erase the summer shoot and promote the autumn shoot. Wipe off the summer shoots of fruiting citrus trees and put them in front of autumn shoots to reduce nutrient consumption and ensure strong autumn shoots. For old trees and trees with a large amount of fruit, autumn shoots should be put earlier, while for young trees, low-yield trees and empty trees, they can be a little later. Autumn shoots are released from late July to mid-August. Sweet oranges are released in August.

Control of citrus diseases and insect pests

Fourth, control diseases and insect pests and promote high yield and high quality. In July and August, when the citrus fruit expands, the absorption of fruit armyworm will cause a large number of fruit drop; rust lice cause defoliation, citrus turns purple-brown; red spiders cause citrus tree atrophy, deciduous orange branches, making leaves white-gray; leaf miner harms new shoots, and larvae feed under the epidermis of tender leaves, making the leaves curl and affect growth. In this regard, in addition to strengthening soil management, regular irrigation and protecting trees and fruits, rust wall lice can be sprayed with 80% Densen zinc 600x or triclofenac 500x. Leaf moth can be sprayed with 1000 times of 50% dichlorvos or 1000 times of 90% trichlorfon combined with 02-degree stone sulfur mixture. The high incidence of fruit-sucking armyworm around August should be timely controlled, and the wild plants inside and outside the citrus orchard can be removed. In the muggy night, the effect is also very good.

The main diseases of citrus are canker, scab and anthracnose. If a disease occurs, it can be sprayed with Bordeaux solution of 1, 100 Bordeaux, or 50% carbendazim, thiophanate 800 times, 50% carbendazim 600 times.