MySheen

Pay close attention to treatment of Cotton Cancer

Published: 2024-11-05 Author: mysheen
Last Updated: 2024/11/05, Fusarium wilt and Verticillium wilt are called "cotton cancer" by cotton farmers. At present, due to the high temperature and heavy rain for many days, the cotton field appears to be "a very good situation". However, during the field investigation, the author found that there are still diseased plants of Fusarium wilt and Verticillium wilt in the cotton field, with the dry edge of the lower leaves extending inward and showing a chlorosis and yellowing shape. the whole plant is poor in growth and relatively short. I especially remind cotton farmers not to take it lightly. First, the characteristics of the disease. Fusarium wilt and Verticillium wilt mainly carry bacteria in soil (Fusarium wilt can survive in soil for 7 ~ 10 years, Verticillium wilt.

Fusarium wilt and Verticillium wilt are called "cotton cancer" by cotton farmers. At present, due to the high temperature and heavy rain for many days, the cotton field appears to be "a very good situation". However, during the field investigation, the author found that there are still diseased plants of Fusarium wilt and Verticillium wilt in the cotton field, with the dry edge of the lower leaves extending inward and showing a chlorosis and yellowing shape. the whole plant is poor in growth and relatively short. I especially remind cotton farmers not to take it lightly.

First, the characteristics of the disease. Fusarium wilt and Verticillium wilt are mainly caused by bacteria in soil (Fusarium wilt can survive in soil for 7 ~ 10 years and Verticillium dahliae in soil for 6 ~ 8 years), branch and leaf residues of diseased plants, seeds and so on. Long-term continuous cropping, extensive management, soil acidity, soil alkali, low content of soil organic matter, heavy clay of soil, lack of potassium and other factors caused the disease seriously. Some plots often have mixed occurrence of two kinds of diseases. The incidence of Fusarium wilt is closely related to soil temperature and humidity: Fusarium wilt usually begins at 20 ℃, reaches its peak at 25: 30 ℃, and stops developing when it is over 32 ℃. Verticillium wilt also began to occur after cotton entered the bud stage, with the peak at 25-28 ℃, slow below 25 ℃ and above 30 ℃, and stopped at more than 35 ℃.

Second, chemical prevention and control. For the control of Fusarium wilt and Verticillium wilt of cotton, strong disease resistance of varieties is the basic factor, but chemical control is still an essential key measure. According to the idea of "three-in-one" of sterilization, regulation and nutrition, the author summed up several pesticide formulations, which are the dosage per barrel of commonly used manual sprayers: ① 14% Diehukang 20 g + 36% cotton Kujing (trichloroisocyanuric acid, be careful not to mix with organophosphorus pesticides) 15 g + E lead (brassin and nutrient element preparation) 40 g + fulvic acid 50 g. ② 80% allicin 16 grams + 50% carbendazim 30 grams + plain acetic acid 1 grams + more than 50 grams (rare earth multi-element preparation). ③ 14% Difukang 30 g + 80% B allicin 8 g + E conductor 40 g + 35% potassium-rich Liangfeng 25 g.

Third, matters needing attention. According to the weather forecast, ① sprayed "preventive medicine" in time before each rain (or before watering), and sprayed again 1 or 2 times after rain (or watering) to control the spread of germs. At the same time of spraying ②, the effect of root irrigation on seriously diseased plants and surrounding cotton plants was significantly better than that of simple spraying. The above formula of ③ should be used alternately, and no more than 2 times should be used unilaterally.

 
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