The first is fat damage. In essence, it is the harm of salt accumulation, mainly due to soil salinization caused by partial application of chemical fertilizers or excessive application of chemical fertilizers. Problems that exist after fertilizer injury include: first, inhibition of vegetable root development, weakening the function of absorbing water and fertilizer; second, excessive concentration of soil solution and reverse osmosis phenomenon of vegetable plants, resulting in physiological wilting or burning of leaf edges; third, the harm caused by toxic gases; and fourth, the occurrence of vegetable deficiencies.

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    Second, drug damage. There is explicit drug damage with obvious symptoms. There is hidden drug damage, symptoms latent or extended to the next crop of vegetables. The causes of drug damage are improper pesticide varieties or herbicide abuse; secondly, the concentration of the application is too high; thirdly, the purchase of poor-quality pesticides; fourthly, avoiding the use of drugs in the hot season. After the occurrence of pesticide damage, some vegetable leaves quickly lose their green color; some produce focus and perforation; some drop leaves, flowers, fruits or abnormal; some severely wither the whole plant.

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    Third, drought damage. It is one of the key factors restricting the development of greenhouse vegetables. First, the location of the vegetable shed is not appropriate, the local water source is insufficient; second, although there is a water source, but the water quality is poor; third, the amount of water is sufficient, but the ditch, the canal, the drainage, the irrigation facilities are not supporting, there is difficult to get water, hope that the water sigh. Drought not only affects the timely sowing of vegetables and seedling growth, but also affects the normal growth of vegetables. At the same time, it also brings great difficulties to the management of vegetable fertilizers and medicine. The effect of drought sometimes exceeds the damage of fertilizer and medicine.

    Fourth, continuous stubble obstacles. In the same greenhouse, planting the same variety or the same kind of vegetables every year or every season, the yield and product quality decrease year by year. The reasons for these obstacles are as follows: first, the same vegetables prefer certain nutrients, nutrients are not timely supplementation, easy to lack; second, the accumulation of soil pathogenic bacteria leads to wilt, yellow wilt and other diseases; third, the same vegetables root secretion substances easily lead to soil microbial community structure imbalance, leading to soil aging.