Management of late rapeseed

Management of late rapeseed management:

Due to the adverse weather or the impact of the former crops, the rapeseed planting was postponed. Late planting of rapeseed is very unfavorable for capturing high yield, mainly affecting autumn and winter hair. It is easy to make vegetative growth poor, and it is not good for vegetative body. Therefore, it is especially important to strengthen the winter management of delayed planting of rapeseed, especially before winter management. According to the test, as long as the tube is good before winter, late planting of late rape can also achieve high yield. The main management measures are:

Apply seedling fertilizer early. Late sowing late planting rapeseed grows slowly, and it is necessary to apply seedling fertilizer early to promote growth. According to the test, the nitrogen uptake of rapeseed is 45% of the whole growth period, 50% of phosphorus and 43% of potassium, accounting for almost half of the total fertilizer. After the rapeseed is transplanted and returned to green, it is necessary to promptly apply the seedling fertilizer, the sooner the better. Generally, the amount of urea used is 2.5--5 kg, the potassium chloride is 5 kg, the boron fertilizer is 300--500 g, and the manure water is 10-20 dan, and the application is carried out 1-1-2 times to make full use of the winter temperature and light resources. Rapeseed has early roots and long leaves, which lays a foundation for high yield.

Heavy application of wax fertilizer. Due to the slow growth of late rapeseed, the seedlings are small during winter and the cold resistance is poor. Therefore, it is necessary to re-apply the secondary fertilizer in the middle of December to improve the soil temperature. The fertilizer should be based on organic fertilizer, the general fertility medium field, the acre of pig and cow manure 25, and the boron fertilizer 12 kg. 10--15 kg of ammonium bicarbonate, the three fertilizers are evenly mixed and applied in the rapeseed line, combined with the clear ditch, the soil is rooted, and the soil is covered on the fertilizer, which can reduce the loss of fertilizer and keep warm and antifreeze.

Cultivate the soil. Late-sowed late-planting rapeseed grows slowly, the seedlings are small, and the grass is often seriously damaged, so it is necessary to cultivate early and eliminate weeds. By cultivating loose soil, it enhances soil permeability, increases ground temperature, and promotes root growth. The cultivating should be carried out in different stages, so that the "three shallows and three deeps" are shallow and deep; the rapeseed is shallow and the plants are deep; the sand is shallow and the muddy is deep.

Control early. Delayed planting of late rapeseed is weak due to nutrient growth before winter, and it is easy to produce early and early flowering, which can be controlled according to the situation. The first is to carry out deep cultivating on the fields with better growth and better fertility. In the vicinity of the rapeseed cultivator 7-10 cm, cut off part of the root system, temporarily control the growth, when the rapeseed is yellow, then apply appropriate nitrogen fertilizer. Secondly, the method of re-application of nitrogen fertilizer can be adopted for the rape field with poor growth, which can effectively delay the growth of vegetative growth, increase the growth amount, and prevent the early flowering phenomenon. The third is to pick up the rapeseed field that may be twitched years ago to suppress the top edge of the plant, transfer the nutrients to the lower part of the branch, delay the growth process, and apply nitrogen fertilizer to promote branching after picking.