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杨树花叶病毒病是近几年在杨树上发现的一种新病害。它为害多种杨树,患病严重的树木,叶片长度比正常叶短1/2,宽度窄1/4～1/3,幼树生长量降低30％。杨树发病初期,病叶呈现点状退绿斑,小斑常聚集成不规则黄绿色花斑,叶缘退色发焦。发病后期,叶片呈花叶,叶脉透明,病叶发皱、变厚、发硬,有的变小,甚至畸形。叶柄上能看到黑色坏死斑点,基部周围隆起。顶梢或嫩枝的皮常形成破裂,严重者植株变形萎缩,顶梢干枯。发病多在7～9月份。
Poplar mosaic virus disease is a new disease found in poplar in recent years. It harms many poplar trees and seriously ill trees. The leaf length is 1/2 shorter than the normal leaf width and 1 / 4-1 / 3 width. The growth of young trees is reduced by 30%. In the early stage of poplar disease, the diseased leaves showed punctate retrogressive green spots, and the small patches often gathered irregular yellowish green spots and the faded edges developed frizz. Late onset, the leaves were mosaic, veins transparent, sick leaves crumpled, thickening, stiff hair, and some smaller, or even deformity. Petiole can see black necrotic spots, around the base uplift. Tops or shoots often form a rupture of the skin, in severe cases, plant deformation atrophy, top dry. Mostly in the disease from September to September.