Strengthening foliar fertilization to improve the boll rate of cotton

The ripening of summer crops in Haimen City has been delayed due to the influence of climate this year, and it has been in a state of drought since the summer harvest, and it did not rain heavily for several days until mid-July. The weather conditions before drought and rain are very disadvantageous to the living and growing plants that have been postponed transplanting cotton, and the growth process is about 10 days later than usual. In order to improve the rate of bud formation and boll formation rate in the later stage of cotton, it is suggested that foliar fertilizer spraying should be used to strengthen fertilization management in the later stage.

1. Grasp the rhythm of fertilizer in combination with pest control. It is not necessary to apply fertilizer for every pest control. Different types of nutrients such as nitrogen, phosphorus, potassium and trace elements should be applied alternately. The same nutrient should be sprayed once every 7-10 days, and different nutrients should be sprayed every 3-5 days. Such as the first time with nitrogen fertilizer, the second time with phosphorus and potassium fertilizer, the third time with trace element foliar fertilizer and so on.

2. Select the varieties to ensure the coordination of nutrients. Urea is an ideal nitrogen fertilizer for foliar spraying. 0.5% urea solution is sprayed to the foliar dripping water in the later stage of cotton growth. Potassium dihydrogen phosphate is suitable for phosphorus and potassium fertilizer with a concentration of 0.2%. Trace element foliar fertilizer can effectively reduce the symptoms of element deficiency in the upper leaves and improve the boll setting rate. In addition, humic acid liquid fertilizer can promote root system development and plant health, enhance photosynthesis, regulate plant physiological function, promote plant growth and dry matter accumulation, so as to increase yield and improve quality.

3. Flexible regulation to improve photosynthetic efficiency. Foliar fertilization should be flexibly controlled according to the growth and appearance of cotton. For the cotton with weak growth, it is generally given priority to nitrogen fertilizer, combined with phosphorus and potassium fertilizer; the growth is generally combined with nitrogen, phosphorus and potassium, and those with strong growth are mainly phosphorus and potassium fertilizer, combined with chemical control, adding 3 to 3.5 grams of pure methyl piperf per mu plus water spray. Trace element foliar fertilizer is suitable for all kinds of cotton fields, especially in the fields with weak growth.