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一、缺氮征状1.玉米:植株呈淡绿色,叶黄色,老叶尖端干枯。叶片中心部分较边缘部分先变成黄色,据此可与缺钾病象相区别,缺钾时,叶片边缘部分较中心部分先变黄色。茎细瘦。2.大豆:生长缓慢,分枝减少,植株矮小。叶子变成淡绿色,然后变为黄色。整个叶子颜色变化都一致。已经变黄的叶子,如及时加施氮肥,即恢复正常绿色。3.棉花:植株细弱,分枝少,叶片呈黄绿色,下部叶子在成熟前即干枯脱落。
First, the nitrogen deficiency symptoms 1. Corn: plants were light green, yellow leaves, the tip of the old leaves dry. The central part of the leaves turned yellow first compared with the marginal part, which could be distinguished from that of potassium deficiency. When the potassium was deficient, the edge of the leaves became yellow first than the central part. Slender stems. 2. Soybean: slow growth, reduced branches, plants short. The leaves turn light green, then yellow. The entire leaf color changes are the same. Leaves that have become yellow, such as nitrogen fertilizer in a timely manner, that is, to restore normal green. 3. Cotton: thin plants, less branches, yellowish green leaves, the lower part of the leaves before they mature off.