Where is the origin of carrots?

Carrots are native to West Asia and Afghanistan. /kloc-was introduced into China through Iran in the 20th century.

Key points of carrot cultivation

1, variety selection.

In autumn cultivation, varieties with a growth period of 90 ~ 1 10 days are generally selected, which requires strong adaptability, especially high and low temperature tolerance, strong disease resistance and high yield. The varieties suitable for planting in the north are Xi 'an Carrot, Anyang Carrot, Jingbianhong, Touxinhong, Tongtouhong, Pheasant Red and so on.

2. Plot selection and soil preparation and fertilization.

In order to ensure the quality of carrots, it is suggested to choose loam or sandy loam with high terrain, good drainage, deep soil layer, loose texture and high organic matter content. For example, when planting in cohesive soil, the amount of farm manure should be increased, or a certain amount of plant ash should be applied during ploughing.

After the previous harvest, dig deep into the land in time, with a depth of 25 to 30 cm. Combined with soil preparation, 3000 ~ 5000 kg of organic fertilizer, 30 kg of diammonium phosphate and 0/5 kg of potassium sulfate/kloc can be applied per mu. Remove sundries, rake the ground flat to make a ridge, generally made into a small ridge with a width of 60 to 80 cm, a height of 10 to 15 cm, and a furrow width of 20 cm. The border is covered with high and deep furrows. For plots with poor drainage and heavy soil, high ridge cultivation can be implemented.

3. Sow in time.

The northern summer and autumn carrots should be sown in the middle and late July, not later than beginning of autumn. Dry seeds are generally used for direct seeding of carrots in autumn, but in order to improve the emergence rate, seed soaking can also be used to accelerate germination.

The method is: soak the seeds in cold water for 3-4 hours, drain the water, put them into cotton bags, keep moisture at 25 degrees to accelerate germination, and sow when 10%-20% of the seeds turn white. Soak in cold water every 12 hours during germination to increase the oxygen in the bag and prevent the formation of harmful substances such as organic acids and microorganisms. When sowing, ditch at the top of the border according to the row spacing 15cm and the ditch depth 1-2cm. Water first, then sow and cover the soil. It is covered with wheat straw and hay.

Autumn carrot is sown in high temperature and dry season, and the temperature is not suitable for carrot seed germination and seedling growth, and the seedling rate is lower than that in spring. Therefore, the sowing amount should be appropriately increased, and the amount of seeds used per mu is 65438 0.2 ~ 65438 0.5 kg. When the seeds are about to emerge, remove the mulch and spray it on the boundary surface with a sprayer. Spraying once a day for 3 to 4 days is beneficial to the emergence of carrot seeds. In sunny areas, after sowing, shading nets can also be used to shade the sun, and the shading nets are required to be about 1 m off the ground.

In order to improve the emergence rate of carrots, it is best to arrange the sowing time after four o'clock every morning or afternoon. After sowing, you must pour enough water, and the plots with poor soil moisture and convenient irrigation and drainage can be irrigated. In addition, cover the soil evenly after sowing, and do not expose the seeds. Before emergence after sowing, in case of dry weather and poor soil moisture, water can be sprayed in the morning or evening, and the soil must be kept moist before emergence.

4. Tian Tuan management

(1) spacing and seedling fixing.

When the seedlings are 1 or 2 true leaves, perform the first thinning to prevent the seedlings from crowding; Use 3 or 4 real leaves for the second thinning, mainly to retain the strength and remove the weakness, and then fix the seedlings. The spacing between seedlings is about 15cm, and 27,000 ~ 32,000 seedlings are left per mu. Every thinning is combined with intertillage to weed and loosen the soil. In order to make the epidermis of fleshy roots have the same color, there should be no "green head", and it is best to use the method of punching holes to facilitate the soil cultivation during the swelling period of fleshy roots.

(2) Reasonable watering.

The furrow irrigation method is adopted, and the appropriate amount of water is used to wet the border surface. Moisture should be ensured during germination to facilitate the emergence of seedlings. Less water is needed at seedling stage, so as to squat seedlings, inhibit the growth of shallow roots and promote deep roots to enter the soil layer. At the peak of leaf growth, fleshy roots gradually expand and need more water. At this time, we should pay attention to keep the soil dry and wet, and supply water evenly to the fleshy roots at the peak of leaf growth to improve the quality and obtain high yield. Excessive watering should be avoided in the late growth stage of fleshy roots to avoid root cracking. In case of heavy rain in the southern region, ditch and drain in time to prevent water accumulation.

(3) topdressing.

Top dressing for 2-3 times from seedling to harvest, and topdressing urea 10- 15 kg each time. If the overgrowth of aboveground parts occurs, paclobutrazol with a concentration of 100 mg/L can be sprayed twice, with an interval of about 1 0 day.