Key techniques for high yield of rapeseed

Rape, an annual herb, has erect roots, erect stems, few branches and 30~2250px in plant height. Rape is an edible crop with strong cold resistance. The lowest temperature of rape seed germination is between 4 and 6 ℃, and the rape growing in the area with large temperature difference between day and night is more likely to blossom and produce mature pods, and accumulate more dry matter and oil content. The unflowered rapeseed is green, with only a few green leaves, and the stem is thick and thin; in the period of exuberant flowering, the flowers are small, golden and tender, so they are of great ornamental value. For this reason, some landscapes also specially plant rape flowers as scenic spots for tourists to enjoy when they bloom; after the flowers wither, they will produce purple-brown pods with long 3~200px, wide 2~3mm and a 9~24mm beak at the apex, which can be planted and squeezed. It is determined that for every 100 kilograms of rapeseed, the ratio of nitrogen, phosphorus and potassium is 1: 0.35: 0.95, which is more than 3 times that of general cereal crops. In addition, rape is sensitive to trace element boron, and the lack of boron is easy to cause flowers and unfruitful.

1. Improved variety selection

At present, rapeseed varieties planted in China mainly include Brassica napus, Brassica napus and Brassica napus. Under the condition of clearly understanding the soil conditions, meteorological conditions and other factors in the planting area, rapeseed varieties suitable for planting in this area should be selected, on the contrary, rape varieties with high quality, disease resistance, high yield and bolting tolerance should be given priority, such as Huaguan, Jinglu No.2 and so on.

two。 Planting method

The cultivation of rape includes two ways: direct sowing and seedling cultivation. In our country, the method of direct sowing is generally used when the planting area of rape is large, and the method of seedling cultivation is generally used when the planting area is small. In addition, because the particles of rape seeds are small, only 1000 rape seeds have the weight of 2.5g~4g. Therefore, in order to improve the success rate of planting as much as possible, different row spacing should be selected according to the method of planting rape. For example, 2.5~1000px row spacing for green feeding, sowing rate 0.3~0.4kg/ mu, if it is used to extract oil, we should increase the row spacing and reduce the sowing rate to increase the yield of rapeseed. For rape cultivated through seedling cultivation, the seedbed should be made first, and the land should be planned well. on the premise of preparing fertilizer and irrigation measures, rape seeds should be sowed on the seedbed, and when the seedlings grow to 1 or 2 true leaves, the seedlings will be removed to the cultivated land for secondary planting.

It is very important to pay attention to sowing at the right time, because sowing too late will lead to the delay of listing and the poor product quality caused by missing the best sowing time, which will eventually adversely affect the economic income of the planting unit.

3. Cultivation stage

During the period of rape growth, fertilization, irrigation, pest prevention and other protection work should be carried out to promote the growth of rape seeds or transplanted seedlings. For example, in Chongqing, in the cultivation stage of rape, it is necessary to ensure sufficient and proper moisture, apply fixed root fertilizer and water on the same day after planting, topdressing for the first time 20 days after planting, and re-apply open plate fertilizer in early December. Among them, farm manure 2000kg, urea 10kg, calcium superphosphate 40kg, potassium chloride 10kg and borax 1kg should be applied per mu in arid areas or dry years. For rape planting in the north, in addition to the above-mentioned fertilization and irrigation, we must also take measures to prevent cold and freezing of rape in winter, in addition to heat preservation through the construction of plastic greenhouses, it is also necessary to apply fertilizers containing various elements of nitrogen, phosphorus, potassium and boron needed for rape growth.

Secondly, for some ornamental rape flower fields, we should pay attention to the maintenance of flower fields in the early stage of flowering to avoid some tourists' trampling on flower fields and the discount of rape flowers. Once this happens, it will have a serious impact on the growth of rapeseed, making it unable to reach the most exuberant flowering period.

Moreover, the cultivation period of rape, that is, the growth period of rape, is the most critical period to increase oil production, and the effect of technical maintenance work at this stage will directly affect the final yield of the whole year.

4. Harvest

The mastery of the best harvest time of rape is also one of the important technical methods for high yield of rape. During the ripening period, attention should be paid to the control of aphids and bird damage so as to prevent the growth of rape from being affected.

In general, rapeseed can be harvested when a small part of the pod turns yellow, and if you wait until half or more of the pod turns yellow, that is, when the pod of the rapeseed turns yellow, the best harvest time has been missed, because the harvested rapeseed is already ripe; if you wait until rapeseed is fully mature before harvesting, it will also cause greater economic losses. Therefore, we should always pay attention to the growth changes of rape, prepare for harvest in advance, and harvest when the effective yield of rape is the highest.

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