Remedial measures of rapeseed vulnerable to freezing injury in low temperature in winter

Rape is easy to suffer frost injury in low temperature period in winter, there are two common kinds: one is root uprooting and lifting seedlings. In winter, the soil water freezes, the volume expands, and the soil layer is lifted up to pull out the rape root system. The soil freezes at night and the soil sinks, causing rape roots to be exposed or broken, lying on the ground. Extensive cultivation of the field, or because of late sowing, rape plants are small, shallow roots, prone to freezing injury. Second, the leaves are frozen, showing symptoms such as leaf ossification, shrinkage, purplish and so on. After the rape is frozen, take measures to remedy it as soon as possible.

Freezing injury of rape

Use fertilizer to remedy and apply wax fertilizer in time. For the weak rape seedlings that have been frozen, wax fertilizer should be applied as soon as possible, mainly manure, and appropriate application of available nitrogen and potassium fertilizer. On sunny days, 500,750 kilograms of human and animal manure, 10 kilograms of urea, 5 kilograms of potassium chloride or 50 kilograms of plant ash are applied per mu. Rape seedlings frozen due to overgrowth can not apply nitrogen fertilizer, should apply appropriate amount of phosphorus and potassium fertilizer, per mu of potassium chloride 5 kg or plant ash 50 kg 75 kg, calcium superphosphate 7.5 kg. In the fields with serious potassium deficiency, the application rate of potassium fertilizer should be increased to promote the growth of rape seedlings as soon as possible.

Warm up to remedy, sprinkle mulch. The frozen rape fields were covered with straw and other crops to increase the temperature. If possible, 250 kilograms of dried straw per mu can be evenly spread between rape rows, so that the mud can not see the sky and the grass does not form a mass, and then cover the straw thinly with the broken soil in the trench to prevent it from blowing away. Applying plant ash or scorched mud ash to the root of rape can absorb heat and keep warm and cushion the attack of cold current.

Ploughing the soil in the middle, promoting the close connection of the root soil. Weak rape seedlings and rape seedlings transplanted late, the root system growth is not strong, poor anti-freezing ability, coupled with the root system is not in close contact with the soil, it is more vulnerable to freezing damage. For this part of the rape field, it should be ploughed in the middle, so that the edge of the plant is shallow and the interrow is deep, combined with ploughing, dredging the ditch system, taking the soil to obstruct the root, increasing the temperature and heat preservation, protecting the root growth, and preventing the lodging in the later stage.