一、戴帽苗 种皮夹在子叶上而不脱落,子叶不易张开,造成幼苗生长不良。成因:一是浸种时间太短种皮干燥,致种皮容易变干;二是播种太浅,覆土厚度不够压力小;三是过早揭掉育畦上的覆盖物或在晴天中午揭膜,致使种皮在脱落前已变干;四是部分种子成熟度不好,生活力弱,也会出现戴帽情况。对策:(1)播种前要浇足浇透苗床底墒水;(2)要因不同蔬菜种皮厚薄、吸水 First, wearing a cap seedling wallet in the cotyledons without falling off, cotyledon is not easy to open, resulting in poor growth of seedlings. Cause: First, seed soaking time is too short seed coat dry, seed coat easy to dry; Second, sowing is too shallow, the pressure is not enough to cover the soil thickness; Third, premature removal of the cover on the nursery or uncovering at sunny noon, resulting in Seed coat has dried before falling off; Fourth, part of the maturity of poor seed, weak vitality, there will be wearing a hat situation. Countermeasures: (1) before pouring enough to pour enough foot seedling water bed seedlings moisture; (2) due to the thickness of different vegetable seed coat, water