Seed selection and cultivation techniques of rape

Rapeseed, also known as oil cabbage, bitter cabbage, cruciferous, Brassica plants, native to China, its stem color dark green, help such as cabbage, cruciferous cabbage varieties, yellow flowers. Agronomically, many species of oil-bearing plants are collectively referred to as rape. At present, the main cultivation (variety) types of rape are: Brassica napus, Brassica juncea, Brassica napus.

Seed Selection of Rapeseed

For rapeseed seed selection, it is necessary to consider whether the varieties have cold tolerance, drought tolerance and sclerotinia sclerotiorum resistance. The selection of rapeseed can be divided into pure rapeseed and hybrid rapeseed, the requirements for conventional rapeseed are: purity should not be lower than 98%, germination rate should be higher than 92%; for hybrid rapeseed requirements are: purity should be higher than 97%, germination rate should also be higher than 85%. In order to establish efficient rape operation mode, we should first select corresponding rape varieties according to local specific geological climate. In some areas where the environment is relatively harsh, environmental and climatic factors should be considered more in the selection of rapeseed, and more drought-resistant and cold-resistant varieties should be selected. For example, in Inner Mongolia, Qinghai, Gansu and other areas of rape planting is to consider this factor. Qingza No. 5 is a spring rape hybrid with high oil content of 45% and yield of 300kg per mu. It is very suitable for planting in high altitude areas above 2000m in China. It has good drought resistance and cold resistance characteristics.

Specific cultivation techniques

For rape planting, different planting techniques are adopted in different areas. In order to achieve high land utilization rate, some areas adopt multiple cropping after wheat; in some places, only one season is planted, and two crops of single seed direct seeding are adopted. However, these two planting techniques are mainly different in the early stage of land preparation, and the rest are basically the same in terms of sowing and field management, so they will not be repeated here. Below we will make a detailed introduction to these two different planting techniques.

land preparation should

Land preparation for single seed direct seeding

Rape planting is mainly in irrigated land, in spring planting is to pay special attention to the moisture content of the field, if there is drought, to water first. Then, the field plot should be carefully arranged, specifically loosening the soil, maintaining the air content in the soil, so as to make the bottom solid and loose, only in this way can the rapeseed germinate and grow better. In the application of fertilizer, it is necessary to ensure that 1500~2000kg of organic fertilizer is put into each mu as base fertilizer.

Land preparation for multiple cropping after wheat

After wheat harvest, the land is relatively dry, and there are a lot of wheat stubble, and there will be wheat straw left in the field. Before sowing rape, first clean up the wheat straw residue in the field, remove the wheat stubble by manual or machine ploughing, and water the field with poor moisture content. Similarly, under the premise of ensuring high yield, it is necessary to add base fertilizer in the land, usually about 1000kg organic fertilizer.

planting work

After the land is sorted out and ready, it is necessary to sow in due course. There are mainly two ways of sowing seeds: machine sowing and manual sowing. When sowing by machine, the requirements for the land are not very strict, and the soil can be sown by wheat layered seeder without loosening the soil first. The sowing depth is 2~3cm. The rapeseed dosage is generally about 1.5kg per mu. It can be preset to sow about 150,000 plants per mu. Diammonium phosphate should be added as seed fertilizer in layers during sowing. The specific specification is 5kg per mu.

When sowing seeds by manpower, the first thing to do is to require the land to be relatively good, to be manually managed and the moisture content to be good. The soil is loose, and after sowing by manpower, it is also necessary to sprinkle diammonium phosphate once, and the specifications are the same as above.

fertilization work

In addition to adding base fertilizer to the land when preparing the field, scientific and reasonable fertilization of rape should be continuously carried out during the growth cycle of rape. First, when the rape grows to 3~4 leaves in the field, urea should be added at one time, and the specific dosage is 2.5kg per mu. In addition, in the flowering period of rape, in order to prevent yellowing of leaves, bud shedding and other phenomena, fertilizer should also be added. Specifically, 0.1kg of potassium dihydrogen phosphate, 0.05kg of boron fertilizer and 15kg of water are uniformly mixed and sprayed on rape leaves.

Specific field management work

First of all, after sowing, rape seeds do not germinate, if there is heavy rainfall, so that the planting ground appears plate phenomenon, at this time to timely break the hardening work, so as not to affect the normal germination and growth of rape. After rape emergence, pay attention to the removal of weeds on the ground, because rape seedlings are difficult to distinguish from weeds, so be patient and careful in weeding work. When the rape grows to about 20cm, it is necessary to irrigate it in real time according to the land conditions. Fertilizer should be applied in combination with irrigation, generally urea 5kg as topdressing.

pest control

Pest and disease prevention work is mainly divided into pests and diseases. Below we will introduce them in detail:

Disease:

The disease of rape is mainly sclerotinia sclerotiorum, which can occur from seedling stage to mature stage of rape, mostly at the base of stem, long depression affected part. This pathogen not only affects the yield of rape, but also has a great impact on the quality and oil yield of rape. Specific control measures should be mainly agricultural control, drug control secondary. The concrete contents are as follows: in agricultural rotation, we should do a good job in the prevention and control of sclerotiorum, select high-quality rape varieties with strong resistance to sclerotiorum, do a good job in rational fertilization, and soil and water irrigation. In the aspect of drug control, suspension seed coating agent is mainly used for coating before sowing, and the specific specification is that 1000 ml of suspension seed coating agent with concentration of 2.5% is coated with 100kg seeds. In addition, spray 700 times solution of 20% clerotium on leaves at bud stage or early flowering stage, spraying times should be more than or equal to three times, the specific situation depends on local planting conditions.

Insect pests:

Rape pests are mainly diamondback moth, aphid, cabbage worm, jump a. There are different pests in individual areas, and prevention and control work can be carried out according to local actual conditions. First of all, in order to control pests, the seed dressing should be carried out before sowing rape, and 500 g of 70% resveratrol dispersible powder can be used for seed dressing with 100kg of seeds. During the growth process of rape after germination, drugs should be sprayed. Specifically, 500 ml of fenvalerate and 500ml of fenthion can be dissolved into 1000 times solution in water for spraying. According to the pest situation, the pesticide can be appropriately increased.

Rapeseed "two defenses and one spray"

The bud and flowering stage of rape is the key stage of seed formation and disease and pest control. Therefore, it is necessary to seize the favorable opportunity to carry out "two prevention and one spray" to control the harm of rape sclerotinia sclerotiorum and aphids, spray boron fertilizer and improve rape yield.

I. Spray time

Cloudy day spray, sunny day before 11 am, after 15 pm spray effect is good. Spray with the wind on a breezy day, not on a windy day

II. Control methods

1. Sclerotinia sclerotiorum control: in bolting stage, spray 100g potassium dihydrogen phosphate plus 50% carbendazim WP or 40% Sclerotinia sclerotiorum WP on 50kg water once per mu, spray the whole field of plants and fields, spray once at initial flowering stage, full flowering stage and angulation stage respectively. At the same time, the old, yellow and diseased leaves in the middle and lower parts of the plant were picked and taken out of the field.

2, aphid control: mu with 1.8% abamectin imidacloprid 25 - 40 grams or mu with imidacloprid 10 grams or 15 - 20 ml of enemy kill. Add 25% carbendazim wettable powder 100g or 40% clerotium wettable powder 100 - 150g, add 30- 40kg water to spray disease and insect control.

3. Spraying boron fertilizer: spray 100 grams of common boron fertilizer per mu; add 200 grams of potassium dihydrogen phosphate or 0.5-1 kg of urea to the nutrient-deficient fields, and spray 75 kg of water evenly.

4. At the same time, it is necessary to clear the ditch, dredge the "three ditches", drain the waterlogging, remove the dark stains, and promote the normal growth of rape roots.