水稻增产巧施锌□周伯瑜周亦杨海月水稻缺锌，多在栽秧后１５天～２５天出现症状。其特点是：植株基部老叶出现褐色斑点，缺锌严重时，叶上褐色斑点逐渐扩大，乃至全叶呈褐色，基部老叶枯死，远看焦枯似火烧状。在观察、鉴别水稻缺锌症状时，往往易与缺钾症状混淆。水稻... Rice yield Qiao Shi Zun □ Zhou Bo Yu Zhou Yijia Yang Haiyue Rice zinc deficiency, and more in the 15 days after planting 25 days symptoms. Its features are: the old leaves of plants appear brown spots, severe zinc deficiency, brown spots on the leaves gradually expanded, and even the whole leaf was brown, the old leaves at the base of the dead, far looks like coke burned like. In the observation and identification of zinc deficiency in rice symptoms, often easy to be confused with symptoms of potassium deficiency. Rice ...