Specific drug for brown blight of grape ear axis

Before sprouting, spray Baume 3-5 degree stone sulfur mixture, or 45% crystal stone sulfur mixture 30 times, 0.3% pentachlorophenol sodium 1-2 times; spray 75% chlorothalonil wettable powder before and after flowering 600,800 times, or 70% mancozeb wettable powder 400,600 times, or 40% carbendan wettable powder 1500 times, or 50% propofoin wettable powder 1500 times.

1. Symptoms of brown blight of grape ear axis

Grape rachis brown blight is mainly harmful to the young rachis tissue of grape panicles. At the initial stage of the disease, brown water-immersed spots were first produced on the branched rachis of young spikes, which caused brown necrosis, dehydration, wilting or shedding of fruit grains. The young fruit only produces small round dark brown spots with a diameter of 2 mm on the epidermis. With the enlargement of the fruit, the surface of the spot is scab-like. When the fruit grows to medium size, the scab falls off and the ear shrinks.

2. Transmission route of brown blight of grape ear axis.

In the next spring, the young buds germinated to the flowering stage and the conidia invaded. After the disease spot was formed, the disease part produced conidia, which was transmitted by wind and rain and re-infected. If it is cold and rainy in early spring, the young tissue (ear rachis) lasts for a long time, the Lignification is slow, the plant is thin, the pathogen spreads quickly, and the disease becomes more and more stable with the aging of ear rachis. Old trees are generally more susceptible to disease than young trees, and the disease is aggravated by insufficient fertilizer or maladjusted ratio of nitrogen and phosphorus, low-lying terrain, poor ventilation and light transmission, and serious disease when the environment is closed.

III. Grape varieties susceptible to disease

The highly resistant varieties were longan, rose dew, Campbell early, dense and purple, rose fragrance, followed by northern alcohol, white banana, black Han and so on; the most susceptible varieties were red banana, red perfume, black Orin, red Fuji and Jufeng.