Technology of sowing whole Seedling of Cotton covered with plastic Film

Baicheng City, located in the west of Jilin Province, belongs to the continental monsoon climate. The contradiction between the long growth period of cotton and the shortage of heat resources needs to be solved in planting cotton. In order to achieve a bumper cotton harvest, we must first sow and take the whole seedling. In order to make efforts on adequate moisture, superior seed, fine sowing, film protection and healthy seedlings in production, we must do a good job in the "five passes".

I. soil preparation and fertilization

1. Choose soil: cotton is a temperature-loving crop. It is better to choose Pinggang sand (soil) land for planting, and the previous crop is suitable for Gramineae crops and bean stubble, which is more suitable for continuous cropping.

two。 Irrigation to create soil moisture: cotton seed bud potential is weak, to artificially create soil moisture conducive to cotton seed germination. Irrigation before sowing is generally adopted to improve soil moisture. Plots without irrigation conditions should be ridged with pulp, and water should be stored to preserve moisture.

3. Balanced fertilization: although cotton is resistant to barren, it likes fertilizer very much. to produce 50 kg lint per mu, it needs to absorb 8 kg of nitrogen, 3 kg of phosphorus and 6 kg of potassium. Therefore, balanced fertilization should be applied according to the status of soil fertility. Mainly organic fertilizer, 3000-4000 kg per mu, supplemented by chemical fertilizer, urea 10-15 kg, diammonium phosphate 10-12 kg, potassium sulfate 8-10 kg. The land with water and fertilizer conservation can also apply the nitrogen fertilizer used for topdressing to the base fertilizer.

4. Fine soil preparation: it is better to turn cotton fields in autumn and ridge in spring. After turning the ground, a 90-or 120-centimeter ridge is formed to wait for sowing. Soil preparation requires sufficient soil moisture, good surface soil moisture, flat and fine crumbs, no straw, no stubble, no weeds, no residual film on the soil surface.

II. Seed treatment clearance

1. Seed selection: it is appropriate to select early-maturing varieties with a growth period of 110-125 days and a pre-frost flowering rate of more than 90%, such as Zhongmiansuo 36, 42, Liaomian 17, 18 and so on. The black seed rate (healthy seed rate) should be more than 80%, and less than 80% of the dry seeds should be selected before sowing.

two。 Sunning: 10-15 days before sowing, choose sunny day for 4-5 days, which can promote seed ripening, increase germination rate, sterilize and reduce diseases.

3. Seed soaking: soak the seeds in cold water for 24 hours two days before sowing, soak well, soak until squeezed by hand, cottonseed squeezed out, control and dry. Seeds stripped with sulfuric acid do not need to be soaked.

4. Seed dressing: seed dressing before sowing is mainly for the control of diseases and insect pests. Every 50 kg seeds are mixed with 100 grams of carbofuran, dimethazone or chlorpromazine 200 grams, first mixed with fungicides and then mixed with insecticides, sown for 24 hours, spread out to dry for sowing.

Third, the quality of sowing

1. Sowing at the right time: the ability of cotton seedlings to endure low temperature is poor, but it is necessary to ensure sufficient growth period, so it is necessary to sow seeds at the right time. It is generally appropriate to sow seeds on April 20-30, no later than May 5 at the latest.

two。 Secrecy: sowing ditches 10 cm 13 cm deep on the formed sowing ridge, 90 cm 2 rows, 120 cm 3 rows, planting in the sowing ditch, 6 seeds per row, plant spacing 13 cm 18 cm, in line with the principle of "fertile land should be thin, thin land should be dense" to determine the density, the land with poor soil moisture should be watered to increase soil moisture, and then cover the seeds with 2cm thick fine soil.

3. Spraying to control weeds: after sowing and covering the soil, close the ridge surface with herbicides to control weeds. Mu with 40% "Lasso" 250 grams or 90% "Horace" 45 ml, mixed with water 20-40 kg, evenly sprayed on the ridge surface, and then grasp the film.

4. Film mulching temperature: to ensure the quality of the film, pay attention to the long stretch, so that the film is as flat as a mirror, the wind can not be blown off, can not be blown bad. After mulching, there should be a gap of 7cm to 10cm between the sowing ditch and the film to prevent the seedling from being burned by the top membrane after emergence.

IV. Protection of plastic film

1. Press the plastic film mulching soil: there are many strong winds in spring in Da'an City, so it is easy to lift the plastic film and lose the function of warming and preserving soil moisture. Therefore, special attention should be paid to the protection of plastic film. After covering the film, press the soil every 2 to 3 meters on the ridge surface, or pack the earth pressure film in a convenient bag.

two。 Irrigate the film mulching water: after sowing, gently irrigate the film pressing water in the ridge and ditch, so that the soil on both sides of the film is moist, and the strong wind can not open the film. Cotton fields with moist soil should not be irrigated as far as possible to prevent the occurrence of blight caused by low ground temperature after irrigation.

3. Keep an eye on the plastic mulching field: the cotton field after plastic mulching is easy to be trampled and covered by livestock and birds, and it is also easy to be lifted by strong winds, so you should often go to the field to take care of the plastic film and protect the plastic film in time.

Fifth, keep the seedlings healthy and healthy

1. Wind to attract seedlings: when about 80% of the cotton seedlings are unearthed, a vent is pierced every 2 to 3 meters, and after 3 to 4 days, a five-cent coin hole is placed above each seedling hole to train the seedlings. After the final frost (usually around May 15-20), the seedlings were introduced to avoid the high temperature at noon, 2 to 3 seedlings per plant, and 1 to 2 seedlings in the plots with less diseases and insect pests. Seal the cotton seedlings with soil to prevent the cooling and breeding of weeds after ventilation.

two。 Thinning seedlings and fixing seedlings: timely thinning seedlings can promote the early development of seedlings and prevent the emergence of "high seedlings" and weak seedlings, thinning seedlings when 1 / 2 true leaves, 1 / 2 true leaves and 1 seedling per shoot, and the fixed seedlings should be finished at the end of May.

If the seedling is exposed to low temperature and high humidity under the film, the blight disease is easy to occur. Kubiqing and mancozeb can be sprayed for 3 times, and foliar fertilizer of "spraying Shibao" is added to promote the growth of healthy seedlings.