Explanation of prevention and control techniques of grape black pox

Grape black pox disease, also known as grape scab, grape bird eye disease, occurs in all producing areas, and it is an important disease in grape production. The disease mainly harms the green and tender parts of grapes, such as leaves, petioles, fruit stalks, tender shoots and young fruits, which can occur from budding to the later stage of growth. So what are the harmful symptoms of grape black pox? What is the prevention and control technology?

First, what harmful symptoms does grape blackpox have?

1. Branches

The new tip disease spot is round brown spot at first, then expands into long oval or irregular spot, the edge is purplish red to dark brown, the inside is grayish brown, and the central depression is cracked. The disease spot is often connected into one piece, and the disease tip is often withered because of the circumcision of the disease spot. The symptoms of tendrils, petioles, flower rachis, fruit stalks and ear rachis were similar to those of new shoots. The disease spot on the thick vine becomes a large ulcer, and the color in the middle is light and split.

2. Leaves

The disease spots on the leaves are needle-sized black-brown spots, surrounded by yellowish-brown halos; enlarged spots are round or irregular in shape, 1~4mm in diameter, purple-brown to dark-brown edges, gray-white in the center, ruptured and perforated when dry. Sometimes the disease spot occurs in a series at the leaf vein, the disease spot on the leaf vein is fusiform and slightly sunken, and the young leaves are wrinkled and twisted into deformities due to the cessation of growth after the vein is killed.

3. Fruit

Red-brown to black-brown dots are produced on the young fruit, and the disease is often cracked in the later stage, and the diseased grains wilt and turn black, dry and fall off. After growing up, the fruit is round, 3~8mm in diameter, purplish brown to purplish red on the edge, brown inside, gray-white in the center, slightly sunken, bird's eye-like, surface hardened, and sometimes cracked. Multiple disease spots can be connected into large spots, the disease spot is limited to the fruit surface, does not go deep into the fruit, but the fruit taste sour, the loss of edible value.

2. Prevention and control of grape black pox.

1. Utilization of disease-resistant varieties

There are obvious differences in the resistance of different varieties to black pox. Before planting in the vineyard, the local production conditions should be considered and the varieties with high commercial value and disease resistance should be selected. For example, Jufeng variety is moderately resistant to black pox, while others, such as Cambel, Rose Dew, Jifeng 14, White Banana, Bako, Saibier 2003, Sabir 2007, Noble fragrance, Crystal, Golden Queen, Blue France, Garry, Giemsa and so on, are also more resistant to black pox, and can be selected according to local conditions.

2. Clear the garden in winter

As the primary infection of black pox mainly comes from the overwintering mycelium on the residual body, it is of great significance to do a good job in clearing the garden in winter, reduce the number of bacteria in the initial infection and slow down the development of the disease. When pruning in winter, cut off the diseased branches and the remaining diseased fruit, scrape off the diseased and old bark, thoroughly remove the dead branches, fallen leaves and rotten fruit in the orchard, and then burn them. Diseased shoots, diseased leaves and diseased fruits were removed at any time during the growing season and destroyed.

3. Pruning in time

The north-south trending scaffolding, single dragon stem, short branch or very short shoot pruning, single branch renewal and bow are adopted in the west of Henan province. In the growing season, it is necessary to wipe buds, fix shoots, prune, pick hearts, beat leaves and other work in time, so as to prevent branches and leaves from being too dense and squeeze, so as to maintain an appropriate proportion of technology, leaves and fruits, so as to ensure good ventilation and light transmission, strong growth of trees and enhanced disease resistance.

4. Bagging the ear in time

Timely bagging of ear, isolation of bacteria and protection of young fruit is also an important measure to prevent and control black pox and produce pollution-free fruit.

5. Increase the application of organic fertilizer

Increase the application of rotten organic fertilizer to ensure the comprehensive nutrition and robust growth of the tree. Pay attention to the amount of nitrogen to prevent greedy green from growing.