The main symptoms of cucumber leaves with white nets are: In the production of cucumber in the protective field, white net edges appear in the middle and upper leaves of the plants. Many symptoms begin to appear from the tips of the leaves and develop along the edges of the leaves. When severe, it also develops toward the interior of the blade. The leaf margins are dry in the late stages.
Cause of the disease: This is due to magnesium deficiency caused by excessive potassium, because in the soil when the potassium concentration is too high, it will affect the cucumber's absorption of magnesium, according to the relevant test proved that when the soil potassium and magnesium The ratio of 8:1 will cause magnesium deficiency, leading to the emergence of white mesh leaves.
Control methods: First of all, to balance the fertilization - base fertilizer used to fully decompose the organic fertilizer, nitrogen, phosphorus, potassium and other fertilizers to be a reasonable application, especially phosphate fertilizer can not be too little. Then pay attention to the application of magnesium fertilizer - sand and sandy loam will generally be lack of magnesium, so you should strengthen the application of magnesium fertilizer, choose calcium magnesium phosphate fertilizer, magnesium ammonium phosphate fertilizer, etc.; also timely spraying 2% sulfuric acid Magnesium aqueous solution.
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