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一、小麦症状:主要表现植株矮小细弱,生长缓慢,分蘖少而弱,叶片窄小直立,叶色淡黄绿老叶干枯,次生根数目少,茎有时呈淡紫色,穗形短小,千粒重低。防治措施:苗期、返青期缺氮,每667平方米可追施尿素5千克,拔节期再追施10~15千克。对于抽穗后叶色变淡、有缺氮症状的麦田,每667平方米可用1~2千克尿素兑水50~60千克进行叶面喷施。二、玉米症状:幼苗生长缓慢,叶片呈黄绿色,植株矮小;三叶期缺氮叶鞘呈紫红色,叶片由下
First, the symptoms of wheat: The main performance of plants short and weak, slow growth, less and less tillering, narrow and erect leaves, leaf color yellowish green old leaves dry, the number of secondary roots less stem sometimes lavender, spike short, thousand weight low . Control measures: seedling, youth green nitrogen, renewable 668 square meters of urea 5 kg, jointing and jointing 10 to 15 kg at jointing stage. Leaf after heading for fades, nitrogen deficiency symptoms of wheat fields, every 667 square meters available 1 to 2 kg of urea watered 50 to 60 kg for foliar spray. Second, the symptoms of corn: seedling growth is slow, the leaves were yellow-green, plant dwarf; nitrogen deficiency in the three-leaf stage purple sheath, leaves from the next