What’s symptoms of Grape leaf roll disease ?
Grape leafroll Diseases Grape leafroll disease is a common virus disease in grape production, which is widely spread. Grape leaf roll disease has semi-latent characteristics. It does not show symptoms in most growing seasons. Most Eurasian plants show symptoms only at fruit ripening stage. Leaf symptoms were most obvious from harvest to deciduous stage. Leaf margins were rolled back, veins became yellow or red, only the main veins remained green, while some varieties gradually withered and browned. The disease is harmful and can reduce grape yield by 20%-50%. Disease manifestation The symptoms of grape leaf roll disease vary with environmental conditions and time. The symptoms of grape leaf roll disease vary according to environmental conditions and at different times of the year. Transmission pathway Grape leaf roll virus is mainly transmitted through seedlings, scions and cuttings. Cause of disease Grape leaf roll disease is mainly transmitted