Nébih: Early detection can curb the golden yellow disease of grapes

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The presence of the pathogen can be confirmed by laboratory tests, but the most characteristic symptoms can also be observed on plantations. Infection is indicated by the spoon-shaped leaves, triangular drift, yellowing and dying leaves in spots in white wine grape varieties, and redness between the leaf veins in blue grape varieties. The leaves harden like paper and fall off, the shoots do not become woody, the canes thin out, become rubbery, and often take on a drooping shape reminiscent of weeping willow. The clusters do not develop properly, the berries are shriveled, have a bad taste, and are low in sugar and high in acid. American grape varieties are often asymptomatic, so the disease can remain hidden.

The pathogen is not capable of spreading independently, and is primarily spread by the American grape cicada

Its individuals can mainly appear on the upper leaves of the shoots, and they need to feed for 7-8 days to develop infectivity. The adult insect is 5-6 millimeters long, light brown-orange in color, the top of the head is slightly pointed, and a black stripe pattern is visible on its front edge. Since they can be easily confused with other species, laboratory testing is recommended for their identification. According to the announcement, the disease has already affected 15 wine regions, its economic damage is severe, and it seriously threatens grape.

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