Apricot trees in greenhouse need to be managed well in spring

The fruit development period of apricot in winter warm greenhouse is from the middle of February to the end of April, which is divided into three main development stages: the first stage is the first rapid growth stage and new shoot growth period, the time is 28-34 days; the second stage is the hard core stage, the time is 8-12 days; the third stage is the second rapid growth period and new shoot growth period, the time is 20-30 days.

The first stage of management: 0.5 kg of nitrogen fertilizer and 1 kg of phosphorus fertilizer were applied to each plant after flowering, and 0.3% urea was sprayed every 7 days in two weeks after flowering. Spray once after spreading leaves or 3000-5000 times of aphid lice. Cut the strong branches of the tree in time after flowering, 3-5 channels per branch, 2-3 cm apart. Three times within two weeks after anthesis, Ziguoling, 0.1% boric acid, 25ppm gibberellin plus 0.3% potassium dihydrogen phosphate, glucose and 300x liquid anti-falling color enhancer were sprayed to increase the fruit setting rate. Erase the improper buds and remove the heart when the new tip grows to 25 cm, at the end of February and the beginning of March. Vegetable fruit branch base of small fruit, deformed fruit, and fruit, disease and insect fruit. The highest temperature in the shed is 20 ℃-25 ℃, not less than 7 ℃ at night, the suitable temperature is 15 ℃-18 ℃, the relative humidity is less than 6%, and the optimum ground temperature is 14 ℃-19 ℃. Try to increase the concentration of carbon dioxide in the greenhouse to prevent the temperature from rising and falling.

In the second stage, we should master two links: 1. Set the fruit. The bouquet-shaped fruit branches leave one fruit, the short fruit branches leave 1-2 fruits, the middle fruit branches leave 2-3 fruits, and the long fruit branches leave 4-6 fruits. 2. Temperature and humidity control. The maximum temperature should not exceed 28 ℃, the average daily temperature should be 18 ℃-22 ℃, and the ground temperature at the depth of 10 cm should be controlled at 20 ℃-24 ℃.

In the third stage, we should pay attention to three points: 1. Fertilizer and water management. Spray 0.2% color 0.3% urea plus 0.2% color 0.3% potassium dihydrogen phosphate every 7-10 days for 2-3 times. 2. Summer shears. Pick the heart when the new shoot is more than 20 cm, and pull the branch at an angle when the backbone branch grows to about 50 cm. In time, apart from the strong shoot and dense branches on the back, open the light path, cut and twist some of the new shoots, so as to promote flower bud differentiation and fruit coloring. 3. Environmental control. Keep the temperature at 26 ℃-28 ℃ during the day, no more than 30 ℃, and 10 ℃-25 ℃ at night, in order to increase the temperature difference between day and night, and the humidity is 50% Murray 60%. Try to replenish carbon dioxide and pay attention to make up the light. Under the premise of not exceeding the maximum temperature, try to increase the greenhouse temperature.