How to manage the expansion period of pear young fruit?

Pear trees like temperature and light, and need more water. The adaptability to the external environment is stronger than that of Apple. Cold-resistant, drought-resistant, waterlogging-resistant and saline-alkali resistant. The cultivated area and yield of pears in China are second only to apples. Summer is the peak period of young fruit growth, so how should the pear young fruit expansion period be managed?

First, apply strong fruit fertilizer

Strong fruit fertilizer not only affects the size and quality of pears, but also affects the quantity and quality of pear flower bud differentiation in the coming year. According to the law of pear root activity and the characteristics of flower bud differentiation, fertilization should be completed at the end of June and the beginning of July. Choose potassium sulfate type compound fertilizer + high potassium and high calcium combination fertilizer, the amount of fertilizer accounts for 30% of the total fertilizer application in the whole year, and generally apply compound fertilizer 50 kg-70 kg + 15-18 kg per mu. Fertilization method: take the crown dripping as the boundary (after the unpulled branch is opened, the branch tip position shall prevail), ring-shaped dig 8-10 fertilizer holes with a length of 0.2 m-0.3 m, apply fertilizer evenly, cover fine soil and water in time after application, at the same time, combined with pest control and foliar spraying 800 times liquid Jiamei platinum or fruit tree gold for 2-3 times.

II. Disease and pest control

Pear trees are vulnerable to diseases and insect pests in summer, so they should be controlled in time.

Fungal diseases include scab, rust, brown spot, ring streak, anthracnose, powdery mildew, dry blight, pear aphid, pear heart borer, pear bug, weevil, longicorn beetle and so on.

Prevention and control measures:

1. Remove disease, insect and diseased shoots manually and bury them deeply.

2. Cut down cypress and other trees to eliminate the parasitic source of rust.

Third, tip control and heart picking

1. Tip control

In order to balance the vegetative growth and reproductive growth of pear trees, 150 times of phosphorus dipotassium or pp0300~500 times spray can be used to control shoots.

2. Pick the heart

Twist or erase the sprouts of the cut mouth and the overgrown branches on the back, wipe the buds in time when the general branches are 4 to 5 inches long, and adjust the ratio of leaves to fruits. For some elongated branches and some groups of elongated branches, the growth of more than 80 cm can be plucked in time to ease the growth and form flower buds.

IV. Water management

Pear trees have three peak periods of water demand: germination-flowering, fruit setting-secondary fruit expansion, and sugar conversion. The secondary fruit expansion period is also a period of high temperature and heavy rain, and the sharp change of soil moisture is easy to aggravate the occurrence of fruit cracking. Especially during the long-term drought and heavy rain during the fruit expansion period, or after a few days of continuous rain, fruit cracking is easy to occur, while the soil in the orchard is too sticky, too many overgrowing branches, more nitrogen and less calcium. In addition, the peel of Cuiguan, Crown, Korla fragrant pear and other varieties are thin and crisp, which aggravate the physiological fruit drop.

How to coordinate soil water management and fruit cracking? Improving orchard irrigation, watering in drought, draining in waterlogging, thinning and pruning some branches, strengthening branch pulling, controlling the amount of nitrogen fertilizer, and increasing the application of phosphorus, potassium and calcium fertilizer are helpful to reduce fruit cracking.

Specific methods: in the fruit expansion period, chelate calcium fertilizer + phosphorus potassium calcium water soluble fertilizer was sprayed continuously for 3 times to supplement calcium in fruit expansion and reduce fruit cracking.