How to prevent rotten fruit from affecting grape yield during grape growth period

Diseases and insect pests are important factors that directly affect the yield and quality of grape, and rotten fruit in the later stage of grape growth is the main reason to harm grape yield. In order to avoid fruit rot in the later stage of grape growth, people often use a large number of chemical pesticides, which not only cause excessive pesticide residues in grapes, but also cause pollution to the environment. Therefore, in the actual production process, the plant protection policy of "prevention first, comprehensive management" should be carried out. The following is a brief description of the causes and prevention of rotten fruit in the later stage of grape growth.

Rotten grape fruit

1. The main causes of rotten fruit:

1. it is overcast and rainy, and the air is humid. Like grape downy mildew, white rot, gray mildew and other germs, most of them like the wet environment, which occurs in large numbers in rainy years, causing serious harm and causing rotten fruit.

2. Luxuriant branches and leaves, poor ventilation. Grape frame branches and leaves are too dense, ear retention is too much, ventilation and light transmission is poor, prone to diseases and insect pests, resulting in rotten fruit.

3. Malnutrition and lack of micro-fertilizer. The correct application of organic fertilizer or inorganic compound fertilizer can enhance the resistance of fruit trees to a variety of diseases and insect pests and worsen the nutrition of piercing pests. Excessive nitrogen fertilizer, insufficient phosphorus, potassium and trace fertilizer, and stagnant water in the soil will promote the occurrence of diseases and insect pests, resulting in rotten fruit.

Second, prevention and control methods:

The main results are as follows: 1. Select high quality varieties with strong disease resistance. For example, "Kangtai" grape varieties are not only resistant to cold, but also resistant to downy mildew and powdery mildew. There are also varieties of Jufeng, which are also resistant to black pox and anthrax.

2. The prevention and control of diseases and insect pests should be based on the principle of "prevention and comprehensive management".

(1) Disease control: the disease should be sprayed at the initial stage of the disease. 50% carbendazim wettable powder 500 times, 70% methyl thiophanate 600 times, 50% carbendazim 800 times. According to the disease, the disease was prevented and treated once every 10 days, for a total of 2 times. If you increase the number of times in case of rain, make up the spray in time after the rain.

(2) Pest control: the main pests are thrips, two-star leafhoppers, grape tiger moths and so on. Thrips and two-star leafhopper can be controlled by imidacloprid 2000 × 3000 times, and grape tiger moth can be sprayed with cypermethrin 2000 times or avermectin 4000 × 5000 times.

3. Combined with bagging to prevent rotten fruit. Grape fruit bagging can reduce the harm of diseases and insect pests and reduce fruit cracking and rotten fruit. Bagging should be carried out immediately after ear shaping, a fine spray of germicidal insecticides should be sprayed before bagging, and bags should be removed 1-2 weeks before harvest to promote coloring.

4. Combine summer shearing to prevent rotten fruit. Summer pruning should remove overdense shoots and overgrown branches in time, fine pruning of fruiting branches and timely coring, so as to prevent the imbalance of vegetative growth and reproductive growth and affect the yield of the same year. When pruning, it should be noted that only one full bud is retained in each node of the fruiting branch, and the other lateral buds or accessory buds are all erased; 5-7 days before flowering, 4-5 leaves are left to pick the heart before the uppermost inflorescence of the fruiting branch. In addition, it is also necessary to keep a reasonable amount of flowers to prevent excessive load on the vines. From flowering to fruit expansion, flower and fruit should be thinned in time, and small fruit, deformed fruit, disease and insect fruit and rotten fruit should be removed to improve fruit quality.

5. combined with the formula of soil testing, apply fertilizer scientifically to prevent rotten fruit. Usually apply more farm manure in autumn. According to the soil survey results, chemical fertilizer and bio-organic fertilizer were added to the next spring and summer to make the soil rich in organic matter, loose and fertile, which was more suitable for the growth and development of grape root system.