Methods of ensuring rape safe overwintering and protecting rape seedlings in winter

Rape overwintering

The weather is cold in winter, in addition to the traditional methods, measures can be taken according to local conditions, such as ploughing and soil cultivation, grass cover protection, irrigation against frozen water, post-freezing management, re-application of wax fertilizer, foliar fertilizer, pest control, early bolting control and other measures to ensure rape safe overwintering.

1. Increase the application of phosphorus and potassium fertilizer. Phosphorus can promote rape root development and enhance resistance, while potassium can improve cold resistance, disease resistance and lodging resistance of rape.

2. Loosen the soil to increase temperature. The rape field should be ploughed to loosen the soil, break the soil surface consolidation, improve the permeability and increase the surface soil temperature. Its principles are: dry, cold and shallow ploughing, wet deep ploughing of the soil, loosening before dry rain, hoeing after wet rain. Ploughing before fertilization and holding roots after fertilization is beneficial to increase temperature.

3. Cultivate soil and cover fertilizer. Pick soil and cover soil fertilizer between rape rows, big seedling bacon, strong seedling heart, small seedling cover root, smash evenly with mature soil fertilizer, can be covered with fine soil mixed with some crushed grass.

4. Irrigation and anti-freezing. Irrigation of rape field once before the cold spell can stabilize the ground temperature and effectively prevent dry freezing. Irrigation after freezing should be carried out at noon on a sunny day.

5. Heavy application of wax fertilizer. Before overwintering, topdressing fire soil ash or soil miscellaneous fertilizer between rape rows can increase the soil temperature by 2 ~ 3 ℃, which has the effect of winter application and spring application, applying 1000-1500 kg pig and cow manure or 2500-3000 kg soil mixed organic fertilizer per mu.

Rape overwintering

6. Foliar spraying fertilizer. Potassium dihydrogen phosphate, activating element and Huimanfeng solution were sprayed during overwintering, and 0.2% borax solution was sprayed on boron-deficient rape.

7. Cover grass for protection. Before the freezing injury comes, cover the rape leaves with a layer of crop straw, or sprinkle a layer of plant ash on the rape leaves.

8. Prevent diseases and insects. In order to control rape aphids, green beetles and jumping beetles, 10-15 grams of imidacloprid are generally sprayed with water; 40% omethoate 100 ml and 2.5% enemy can be used to kill 20 ml and spray 150 kg of water, which must be carried out after thawing; for rape fields with severe quenching disease, carbendazim or topiramate can be used.

9. Control early bolting. For early bolting rape, paclobutrazol solution can be sprayed with 15% paclobutrazol powder 35-50 grams per mu, 55-75 kg water, uniform spray to control early bolting.

10. Post-freeze management. It is found that frozen seedlings should be uprooted, soil should be cultivated in time to support seedlings, and rain and snow should be excluded as soon as possible to avoid waterlogging hindering root growth. When thawing, timely spraying plant ash on rape or spraying fresh water on leaves is effective to prevent frost injury and water loss of seedlings.