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小麦和大麦的黄矮病,目前已知是由麦蚜传播的一种病毒病。病株的典型症状:在上部比较幼嫩叶片的叶尖开始发黄,以后发展至三分之一的叶面,最后整个叶片发黄。黄叶的颜色呈桔黄色,鲜艳光泽。但是,下部老叶常常保持正常绿色。病株的高度明显地矮化。在麦子的生长前期,病株在田间呈点片状分布;在生长后期,病株常常单株分散在田间。这些特点可以帮助我们区别于干旱、缺肥、盐碱或蝼蛄为害等原因所
Yellow-dwarf disease of wheat and barley is now known to be a viral disease transmitted by wheat aphids. Typical symptoms of diseased plants: leaf tips begin to yellow on younger shoots in the upper part of the leaf, then develop to one-third of the leaf surface later, eventually yellowing of the whole leaves. The color of yellow leaves is orange, bright luster. However, the lower part of the old leaves often remain normal green. The height of diseased plants is apparently dwarfed. In the early stage of wheat growth, the diseased plants showed patchy distribution in the field. In the late growth stage, the diseased plants were often scattered in the field. These characteristics can help us distinguish ourselves from the causes of drought, lack of fertility, salinization or catharsis