The etiology and control measures of the latest rotten grape fruit

Grape growers usually encounter the phenomenon of grape rotten fruit, especially in the middle and later stage of grape planting, once the rotten fruit, it will seriously affect the grape yield and variety, and bring great economic losses to farmers. As a result, the pro-agricultural network brings us an analysis of the causes of grape rotten fruit and how to prevent and cure the phenomenon of grape rotten fruit.

I. the cause of the disease

1. Bacterial infection. The main diseases that cause grape fruit rot are white rot, anthracnose and black rot in special years. White rot and black rot will not only lead to rotten fruit and ear, but also infect grape branches and vines to form brown disease spots. In serious cases, the diseased branches and leaves withered and the tree is weak, affecting the fruit yield and quality of the current year and the following year.

two。 Bad weather. Rain Water is concentrated in the Central Plains from July to August, and this period is the middle and later stage of grape fruit growth, when the climate characteristics of high temperature, high humidity and rainy are easy to cause the pandemic of the above three diseases.

3. The orchard was mismanaged. Most of the vineyards in the Central Plains use hedge jibs, although it is convenient to manage in summer, but the luxuriant branches and leaves inside and outside the shelf can easily lead to poor ventilation and light transmission, and most of the ears are exposed or crowded in the branches, coupled with more Rain Water and muggy air. It is easy to form a high-temperature and humid microclimate. If mechanical injuries are caused by storm, hail, sunburn, fruit cracking or birds and insects, the prevalence of "fruit rot" will be aggravated. And cause secondary diseases.

4. The tree is weak. The following factors will cause tree weakness and poor disease resistance: insufficient application of organic fertilizer, partial application of nitrogen fertilizer, neglect of phosphorus, potassium, calcium and other nutrients; unreasonable summer pruning, untimely binding, coring, shoot thinning and heading, etc., resulting in poor nutrition supply during fruit growth; too many ineffective branches and leaves, ineffective consumption too much; too much fruit hanging, weeds under the shelf; serious diseases and insect pests, etc.

II. Prevention and control measures

1. Change the hedge boom into a small scaffolding to create a microclimate that is not conducive to the occurrence of diseases. Should use small scaffolding, single dragon stem or double dragon stem pruning, medium and short shoots pruning. It is necessary to ensure that the light on the greenhouse surface is sufficient, and the leaf area index should not exceed 1.5 to 2.0; in the near ripening period of the fruit, the light transmittance under the shelf should be adjusted, which is generally required to be about 30%. In the growing season, summer pruning, vine binding, shoot thinning, heart picking and ear stretching should be done in time to make the ear hang in the "shade of flowers", avoid sunburn or Rain Water residue on the fruit surface, and avoid mechanical injury to the fruit caused by storm and hail.

two。 Strengthen the management of soil, fertilizer and water to enhance the tree potential. The rotten organic manure is applied by alternating ditches every other year, it is best to use chicken manure, combined with appropriate amount of phosphorus and potassium fertilizer. The higher temperature in this period is not only beneficial to the decomposition of organic fertilizer, but also has strong photosynthetic capacity of leaves and can effectively utilize nutrients. In the late stage of grape growth, 2%-3% potassium dihydrogen phosphate solution can be sprayed in combination with medicine, which can significantly enhance the tree potential and reduce the occurrence of "rotten fruit". Plant growth regulators can be sprayed according to plant growth to improve leaf function, tree potential and disease resistance.

After rain, attention should be paid to removing stagnant water in the garden, loosening the soil and weeding in time to prevent excessive soil moisture, and clay soil should also pay attention to soil improvement in order to enhance the air permeability of root soil. Pay attention to improve the fruit area, 40-50 cm on the ground do not leave ears as far as possible, in order to reduce the chance of bacterial infection.

3. Remove the source of bacteria. Remove the sick and disabled bodies in the garden before the branches and vines are removed from the shelves after autumn and burn them centrally. Before burying the soil to prevent cold in autumn and after being unearthed in spring, Solibal 50 × 100 solution or Baume 3% 5 degree stone sulfur mixture + pentachlorophenol sodium 300 times solution were sprayed to remove the bacterial source. In the growing season, diseased leaves, fruits and vines should be removed in time and buried deeply.

4. Strengthen the shelf management. Pay attention to timely binding, heart-picking, keep the frame ventilated and transparent. The yield is determined according to the growth of the plant, and the yield of the general mature orchard should be controlled at 2 500-3 500 kg per 667 square meters.

5. Chemical control. For infected vineyards, spray Baume 2-degree stone sulfur mixture + pentachlorophenol sodium 200 times and 50% bacillus special wettable powder 500 times to the tree body or ground before sprouting, in order to protect and prevent.

For seriously diseased orchards, 1 part of thiram, 1 part of sulfur powder and 2 parts of lime can be mixed evenly and sprinkled on the ground under the grape rack at the initial stage of the disease, 1 kg per 667 square meters. If the disease occurs during the growing period, it can be sprayed with 800 times of 50% Tuishuite wettable powder or 600 times 800 times of 75% chlorothalonil wettable powder, spraying once every 10 to 15 days throughout the growing season, but pay attention to alternate use of drugs.

For orchards with serious disease last year, 500 × 600 times of thiram or 50% carbendazim 500 times of carbendazim should be sprayed under the shelf before the occurrence of the disease to eliminate the source of overwintering in the soil. Bordeaux solution of appropriate concentration should be sprayed every 10 to 15 days in the growing season to reduce the chance of disease infection. In the event of diseases such as white rot and anthrax, drugs should be applied to the symptoms, but attention should be paid to the alternate use of drugs. After the fruit is colored, in order to prevent the ear from being contaminated by pesticides, the disease can be controlled by spraying 12% green milk copper 600 × 800 times.

The above are the causes and related prevention and control methods of apple rotten fruit collected by pro-farm network for everyone. Fruit growers should remember not to panic after discovering the situation of grape rotten fruit, and should earnestly analyze the causes of grape rotten fruit, and then take relevant control measures.