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蔬菜苗期易发病的原因1.幼苗自身的能量消耗大于养分的积累。种子发芽后一段时间内主要利用子叶贮存的养料生长。当养料基本耗尽时,真叶未完全展开,幼根未扎实,幼茎未木栓化。此时,根系吸收能力差,叶的光合作用弱,体内物质不能迅速增加,幼苗的抗病能力不强。当环...
Vegetable seedling easy to cause 1. Seedling itself consumes more energy than nutrients. Seed germination within a period of time after the main use of cotyledons stored nutrients growth. When the nutrients are almost exhausted, the true leaves are not fully expanded, the rootlets are not solid, and the young stems are not corked. At this point, poor absorption capacity of the root system, the photosynthesis of leaves weak, the body can not rapidly increase the material, disease resistance of seedlings is not strong. When the ring ...