早在六十年代初,扬州地区部分果园的桃、梨、苹果树上发现有缺锌的小叶病,以后出现玉米白苗和花叶条纹病,里下河地区部分低洼稻田,早稻经常出现发红的僵苗(俗称戴红缨帽),症状类似缺钾,长期以来缺乏有效措施。1977年我们开始进行锌肥肥效的多点试 As early as the early 1960s, zinc deficiency leaflet disease was found on peaches, pears and apple trees in some orchards of Yangzhou area. Later, corn white seedlings and mosaic leaf streaks appeared. Some low-lying paddy fields in the Lixiahe area were often found with early rice Red stiff seedlings (commonly known as wearing a red cap), symptoms similar to potassium, the lack of effective measures for a long time. In 1977 we started a multi-point trial of zinc fertilizer efficiency