Field management of continuous rainy rape waterlogging damage in winter and spring rape

Combined with the current rape seedling situation and weather conditions, the following suggestions on rape field management technology in winter and spring were put forward:

rape

Ditch cleaning and soil moisture prevention:

11-12 In September, some areas in the middle and upper reaches of the Yangtze River Basin suffered from continuous low temperature and rainy weather, and some rape was seriously damaged. At present, it is in the period of heavy snow, which is the period of high incidence of cold wave, low temperature and rain, and rape freezing injury is easy to occur. To clean up the three ditches as soon as possible, to ensure that the ditches are connected, the drainage is unobstructed, and the rape is seriously damaged and frozen due to continuous rainy days in winter and spring.

Reasonable fertilizer to promote growth:

In view of the problem of insufficient autumn development of some direct seeding rape, increasing wax fertilizer can promote winter development of weak seedlings and realize seedling upgrading. 7~ 10kg rape special formula fertilizer or high concentration compound fertilizer should be applied to the three kinds of rape seedling fields with thin growth as soon as possible. For those with heavy freeze injury, 5~7 kg urea can be applied per mu as recovery fertilizer. For those growing normally, 3~5 kg urea can be applied as wax fertilizer as appropriate. When the budding period in spring is reached, the nitrogen fertilizer is applied once more. The nitrogen fertilizer amount accounts for about 30% of the total nitrogen amount.

Regulation and control of vigorous growth and prevention of freezing injury:

For those growing too vigorously, apply less or no fertilizer, spray 30~ 40g (15%) paclobutrazol or uniconazole per mu in the morning of sunny and warm weather to control the growth and promote the growth, improve the freezing resistance of rape and realize safe winter. For the bolted field, the technique of "one vegetable for two purposes" can be adopted. When the bolting height is about 40cm, the bolting can be picked 15~20cm and eaten to delay the growth process.

"One promotion and four prevention" to ensure a bumper harvest:

Due to frequent occurrence of rape sclerotinia sclerotiorum in recent years, the base number of sclerotinia sclerotiorum in the field is large, and the risk of disease increases. We should carry out "one promotion and four prevention" before and after the initial flowering stage of rape to promote the later growth of rape, prevent flowers from failing, prevent sclerotiorum, prevent "rat tail" and prevent high temperature from ripening, so as to ensure high and stable yield of rape. Generally, it can be mixed with chemicals at one time per mu (100g of 40% Sclerotin WP or chlorpromethrin, 100g of potassium dihydrogen phosphate, 50g of available boron, etc.), the dosage per mu of mobile sprayer is 12~ 15kg, and the dosage per mu of manual sprayer is not less than 30kg/mu.