[grape anthracnose] harm and control methods of grape anthracnose

Grape anthracnose will form brown spots on the leaves and fruits of grapes, and then start to rot a little from the spots, seriously affecting its ornamental value and edible value.

Symptoms of grape anthracnose

Anthracnose mainly occurs on plant leaves, often harms leaf edges and leaf tips, and when serious, causes more than half of the leaves to wither and blacken and die. In the early stage of the disease, there were small round, oval reddish-brown spots on the leaves, and later expanded into dark brown round spots with a size of 1 to 4 mm, with the center changing from grayish brown to grayish white, while the edge was purplish brown or dark green, and sometimes there was yellow halo on the edge. finally, the disease spot turns to dark brown, and produces small black spots arranged in the shape of a wheel, that is, the conidium of the pathogen. There are pink myxospore clusters on the disease spot under wet conditions. In severe cases, there are more than ten to dozens of disease spots on a leaf, and in the later stage, the disease spot is perforated, and the disease spot fuses into pieces for a long time, resulting in leaf dryness. The disease spot can form perforation, and the diseased leaf is easy to fall off.

When anthrax occurs on the stem, it produces a round or subcircular spot, which is light brown, with black dots arranged in a wheel. The disease spot on the tender shoot is an oval ulcer spot with a slightly raised edge.

Control of grape anthracnose

1. Select the non-drop anti-fog film to cover the facility, cover the whole area of the ground in the facility, and pay attention to ventilation and dehumidification, reduce the air humidity in the facility, control the air relative humidity below 80%, restrain spore germination and reduce infection.

two。 Reasonable density, scientific pruning, appropriate amount of branches, reasonable load, maintain strong growth, improve field light conditions, reduce the air humidity of microclimate.

3. Spray protection during the growing season. Spray 240-200 times half-dose Bordeaux liquid carefully every 15 minutes for 20 days to protect the tree. And spray high-efficiency, low-residue, non-toxic or low-toxic fungicides between Bordeaux liquid. The following pesticides can be used alternately: 80% spray gram wettable powder 800 times liquid, 70% gram wettable powder 700-800 times liquid, 50% bacillus special wettable powder 600-800 times liquid, 80% anthrax Fumei wettable powder 600 times liquid, 20% silver fruit wettable powder 600 times liquid and so on. In order to improve the control effect, the non-alkaline solution can be mixed with "Tianda-2116" or 1000 times of drought and waterlogging.

Other diseases susceptible to grapes

1. Prevention and treatment of black pox and downy mildew: in winter, diseased vines, leaves, fruits and withered branches should be thoroughly cut off and buried away from the vineyard after concentrated burning. After that, 5 °Be stone sulfur mixture was sprayed before the plant was about to germinate. After the bud leaves were unfolded, Bordeaux solution or insecticide was sprayed three or four times. Spraying time can be chosen in the grape leaf expansion period, spraying medicine, to make the liquid dispersed to all parts of the grapevine, as far as possible without omission.

two。 The prevention and control of powdery mildew is the same as that of blackpox and downy mildew. In addition, it is necessary to strengthen management and improve the light transmittance and ventilation effect of grapevines. In order to cure and control powdery mildew, it is best to spray Be stone sulfur mixture before budding stage. In the middle of May, 0.2-0.3 low concentration Be stone-sulfur mixture was sprayed. With a two-pronged approach, the control effect is better.

No matter whether it is anthrax, powdery mildew, black bean disease, or even insect pests, we should plant all plants based on the principle of preventing diseases and insect pests, and cultivate and care for plants as correctly as possible, so as to prevent them from being threatened by diseases and insect pests and cause losses.