Planting time and method of rape

Rape has a strong vitality, it is a relatively cold-tolerant crop, so it is distributed in many parts of our country. Rape has a good taste and high nutritional value, so it is very popular when it faces the market every year. Due to the rising price of rape, many people want to grow it.

Planting time and method of rape

Planting time:

The suitable sowing date of rape should take into account climate, planting system, variety characteristics, diseases and insect pests, previous crops and so on. However, appropriate early sowing of winter and semi-winter varieties can make full use of the increase of season and vegetative period. It is beneficial to give full play to the potential of varieties, strive for high yield, and the sowing temperature is generally 20 ℃. The direct seeding time of rape is from late September to the first and middle of October, and the suitable time for seedling raising and transplanting is from the first ten days of September to the last ten days of September.

Planting method:

1. Planting density: suitable planting density. The suitable planting density varies greatly in different areas and under different conditions. The suitable density of Brassica napus in our county is 7000-8000 large plant type and 8000-12000 small plant type.

2. Planting mode: different planting methods can be used for the same planting density.

(1) wide and narrow row: alternating planting with wide row and narrow row can solve the ventilation and light transmittance of higher planting density, increase soil temperature and soil temperature, better coordinate individual and population growth, and is beneficial to topdressing and field management. it is generally 1.4 feet wide and 1 foot narrow.

(2) narrow row and narrow plant: if the row spacing is relaxed and the plant spacing is reduced (for example, the row spacing is 1 foot, the plant spacing is 4-5 inches), the row closure can be delayed. Reduce shade, facilitate ventilation and light transmission, and facilitate field management.

(3) Equal row-plant spacing: the planting method with equal row and plant spacing was adopted at low density, with more uniform branch distribution, more branches and more fruit.

Growth conditions of rapeseed

1. Temperature. Rape is a crop that likes cold and has strong cold resistance. The lowest temperature of seed germination is 3-5 ℃, which can emerge in 3 days under the condition of 20-25 ℃. The flowering stage is 14-18 ℃, the development period of pod is 12-15 ℃, and the temperature difference between day and night is large, which is beneficial to flowering and pod development, and increase the accumulation of dry matter and oil.

2. Moisture. Rape has a long growth period, a large vegetative body, and a large number of organs, so it needs more water. The requirements for water in each growth stage are as follows: the general soil moisture at the seedling stage should be kept at about 65% of the field capacity; from bud stage to flowering stage, it is 75-85% of field capacity, and 70-80% of field capacity during pod development.

3. Fertilizer. Rape is a fertilizer-tolerant crop with strong ability to absorb fertilizer. in the whole growth process, it needs to absorb a large amount of nutrients such as nitrogen, phosphorus and potassium from the soil. According to the determination, for every 100 kg of rapeseed produced, the ratio of nitrogen, phosphorus and potassium is 0.95, and the demand for the three elements is more than 3 times that of cereal crops. Secondly, boron fertilizer is an essential trace element for the growth and development of rapeseed. After boron deficiency, it appears flowering but not fruiting, that is, the young horn is not swollen or unfruited after smallpox. Generally, the production is reduced by 20% to 30%, and there is no harvest for serious particles.

4. Soil. Rape is a straight-root crop with developed root system, deep main root, many branches and fine roots, which requires deep soil layer, good structure, rich organic matter, fertilizer and water conservation, loose and aerated loam or sandy loam. It is more beneficial to increase the yield and increase the oil content of rapeseed in weak acid or neutral soil.

Fertilizing method of rape planting

1. Apply sufficient base fertilizer. Generally, compost 1000-1500 kg and phosphate fertilizer 20-25 kg per mu are mixed and raked into the topsoil during soil preparation, while pig manure water is 1500-2000 kg, mixed with an appropriate amount of chemical nitrogen fertilizer into the seedling bed soil to fertilize the bed soil.

2. It is suitable to apply fixed seedling fertilizer. Before and after the seedling was fixed, the fertilizer water of 500 kilograms of rarefied human and animal manure was applied for 2 times. If the soil is dry and the seedlings are thin, they can be applied more appropriately, and those with strong and wet soil can be applied less. During the period of 4 to 5 leaves, the main control was to stop fertilizing and watering, and squatting seedlings were carried out to prevent the phenomenon of overgrowth in the seedling bed stage.

Prevention and control of rape aphids

1. Chemical control: 40% dimethoate EC or 40% omethoate 1000 × 2000 times, 50% dichlorvos EC 1000 times, 20% aphids 1000 times 1400 times, 50% malathion 1000 times 2000 times, 25% aphid acaroid EC 2000 times, 10% diazinon EC 1000 times, 50% aphid mist wettable powder 3000 times, 50% monocrotophos emulsion 2000 times 3000 times, 40% isocarbophos emulsion 1500 times, or 2.5% diazinon emulsion 3000 times

2. Seed treatment. Seed dressing with 20% aphid pine wet powder 1 kg or 100 kg with methyl parathion, insecticidal and carbofuran can prevent aphids at seedling stage.

3. Cultivation and control. Cover the ground with silver gray, milky white, black plastic film about 50%. It has the effect of repelling aphids and preventing virus disease.

4. Biological control. Feeding and releasing aphid cocoon peak, lacewing, ladybug, aphid fly and aphid mold can reduce the damage of aphids.

Rape is usually planted in early autumn and can be eaten in winter. Rape needs a lot of water during the planting period, so it is necessary to do a good job of watering. The management in the later stage of planting should be done in place, timely fertilization and pest control should be done in time, so as to ensure its yield.