黄瓜在生长期间，如果营养不良，管理不当，或遇不良的气候和某些病害的侵染，往往造成叶片变黄，影响黄瓜的生长，甚至绝收。黄瓜叶片变黄按原因分主要有３类，现简介如下：１缺素型黄叶缺素型黄叶分为中、下部老叶先黄和中、上部嫩叶先黄两种情况。中、下部老叶先黄，所缺元? Cucumber during growth, if malnutrition, improper management, or adverse weather and some diseases of the infection, often cause yellow leaves, affecting the growth of cucumber, or even absolute. Cucumber leaves turn yellow according to the reasons there are three main points, are summarized as follows: A lack of prime yellow leaves lack of type of yellow leaves into the middle and lower part of the old yellow first and the upper leaves of the first two yellow. Middle and lower leaves first yellow, the lack of element?