在严冬或冬春低温季节,日光温室或塑料大棚内常因密闭保温、通风不良和施肥技术不当,造成棚室蔬菜大面积中毒受损。据调查每年都发生不同程度的中毒现象。 氨中毒往往发生在植株外侧的叶片上,主要危害幼嫩新叶,叶面上呈星状分布的焦状斑 In the winter or winter cold season, the greenhouse or plastic greenhouse often due to airtight insulation, poor ventilation and improper fertilization techniques, resulting in large-scale greenhouse vegetable poisoning damage. According to the survey, different levels of poisoning occur every year. Ammonia poisoning often occurs on the leaves of plants outside the main damage to young new leaves, the star-shaped surface of the distribution of coke-like spots