Anthracnose of Grape

Disease

Anthracnose of Grape

Elsinoe ampelina

fungi

In a Nutshell

    Small brown spots develop on the upper side of young leavesAs they enlarge, they turn gray and necrotic, creating a shot-hole effect as they fall outSpots and lesions appear on stems and shoots and can girdle themAshy gray spots with brown margins on berries

Hosts: %1$s

· Grape

Symptoms

The fungus attacks all green parts of the vine, leaves, shoots, stems and tendrils. However, it is the young, rapidly growing tissues that are most affected. On the leaves, small brown spots develop on the upper lamina. As they enlarge, they become irregular and their center gradually turns gray and necrotic. Eventually, the dead tissue falls out, creating a shot-hole effect. The same type of spots and lesions appear on stems and shoots and can girdle them, resulting in the formation of cankers and dieback. Small, round, purple spots also develop on the fruits. They gradually expand and turn sunken and ashy gray with brown margins. As they cover the skin, the berries wither and can drop or become mummified on the cluster. The distinctive spots with ashy gray centers confer to the disease its common name, bird’s eye rot.

Trigger

The symptoms are caused by the fungus Elsinoe ampelina. It overwinters in fungal structures on the shoots and the bark of the infected vines. During the spring, it starts to produce spores that are released and dispersed by rain splashes. Wind and rain carry the spores to young, developing leaves or shoots. Periods of prolonged tissue wetness (12 hours or more) and temperatures from 2 to up to 32 °C favor the production and germination of the spores. The higher the temperature and the humidity, the faster infection will occur and the sooner the symptoms will appear. Cool weather slows the growth of the fungus. Leaf defoliation and direct fruit damage have a serious impact on the yield and quality of the berries.

Biological Control

The application of liquid lime sulfur or copper sprays in early spring, prior to bud break, has been used to avoid a high incidence of the pathogen. Make sure the fungicides are permitted within the organic certification program.

Chemical Control

Always consider an integrated approach with preventive measures and biological treatments if available. Anthracnose can be controlled if good cultural practices are followed along with the timely use of protective fungicide sprays. A spray of liquid lime sulfur or Bordeaux mixture just as the buds are breaking will help reduce anthracnose problems. Pesticides registered to protect the developing new growth and fruit are captan, chlorothalonil and mancozeb. Spray at 2-week intervals from bud break until the fruit begins to color.

Preventive Measures

    Use more tolerant varieties, if availableMake sure to keep a wide distance between vinesChoose sites with suitable sun exposure and good air circulationMonitor the vines and remove fruit or plant parts that show sign of the diseaseRemove plant residues from the vineyardPrune the vines in early winter during dormancyPlow field and bury plant residues and berriesFor homegrown grapes, use leaf mulch or fine bark to cover infected debrisRemove any wild grapes near the vineyard




Features

Regional Weather

Get detailed forecast and actual weather data.

Plantix offers detailed weather information on the following issues:

Precipitation

Humidity

Air Pressure

Temperature

Wind speed

Plantix Community

Get in touch with experts around the world.

Post your questions

You can post your questions and pictures and get feedback from other farmers or gardeners. Plantix' experts will answer your questions related to plant diseases and pests.

MyCommunity

Exchange with Plantix users around you, in your language and related to the crops you grow.

Global Community

Connect to farmers, gardeners, experts and interested people around the world that discuss plant diseases, remedies and best practice for sustainable farming.

AI-Driven Disease Detection

Instant diagnostics and solutions based on your picture

Image Recognition

Plantix analyzes your picture within a few seconds and gives you instant feedback on your plant problem.

Customized Management Options

On top of the detection result, Plantix offers you a detailed description of possible solutions - both biological and conventional.

Preventive measures

Plantix offers information on preventive measures to protect your crop from the next attack.