Cotton cultivation techniques

First, apply enough base fertilizer

The cotton has a long growth period and the root system is deep and wide. It not only requires the surface soil to be rich in mineral nutrition, but also the deep layer of the plough layer should maintain high fertility and release nutrients slowly. The base fertilizer is applied to the soil before the cotton is planted, which can meet this requirement. The base fertilizer is mainly based on farmyard manure, which can be applied to the soil in the autumn and winter seasons, combined with deep tillage and deep ploughing. Generally, the high-quality farmyard manure is 3000-4000 kg, and the Stanley compound fertilizer is 30-50 kg. At the same time, zinc and boron fertilizers are applied for 1 to 2 kg per mu.

Second, sowing

1. Sowing period: The production is generally stable at a temperature of 5 cm above 5 °C above 5 °C, or the temperature is stable above 16 °C for a suitable sowing period. Sowing at the right time can make the cotton plant grow stably, and the buds bloom early, prolong the ringing time, which is conducive to early maturity, high yield and high quality; sowing too early, the temperature is low, which is easy to cause rotten seed lacking; late sowing, postponed each birth period, resulting in Late ripening reduces yield and reduces fiber quality.

2. Seeding rate: The seeding amount should be determined according to the seeding method, seed quality, seedling density and soil climate. Too few to ensure the number of strains that should be in place, affecting the yield; excessively wasting cotton seeds, and will cause cotton seedlings to be crowded, easy to form high-stem seedlings, and increase the use of seedlings. The seed germination rate should be increased as appropriate when the seed germination rate is low, the soil moisture is poor, the soil is sticky or saline, and the underground pests are serious.

3, sowing depth: cotton cotyledon hypertrophy, poor soil ability, sowing depth and seedlings sooner or later, cotton seedlings complete degree and strength is closely related; sowing too deep, low temperature, difficult to top soil, slow emergence, consumption of nutrients, thin seedlings Even causing rotten, rotten buds and lack of seedlings; sowing too shallow, easy to fall, resulting in lack of seedlings and ridges. The depth of sowing depends on the soil and the sensation. In principle, the seeding depth is 3 to 4 cm. Soils with good lyrical and sticky texture should be shallow; soil moisture should be poor, and soil with sandy soil should be properly spread.

Third, reasonable topdressing

1. Lightly apply seedling fertilizer: After applying seedling fertilizer, it can promote root development and cultivate strong seedlings. Miao fertilizer is generally based on nitrogen fertilizer, which can be determined according to the condition of seedling, soil and base fertilizer. For cotton fields with poor ground strength, insufficient base fertilizer, and weak growth, apply 5-10 kg of urea or high-nitrogen compound fertilizer per acre, open the ditch and apply the soil after application. For cotton fields with high fertility and base fertilizer, you can not apply for seedlings.

2. Stable application of bud fertilizer: The demand for nutrients gradually increases after cotton buds, and the bud period is reasonable for topdressing, which can meet the needs of cotton planting, coordinate the relationship between vegetative growth and reproductive growth, and promote the stable growth of plants. Generally, in the early stage of cotton buds, the Stanley compound fertilizer is applied for 15-20 kg. The method of top dressing is better by ditching deep and maintaining a proper distance from the cotton plant to avoid root damage and affect normal growth.

3, re-applying flower bell fertilizer: flowering and bolling period is the period when cotton needs most fertilizer, re-applying flower bell fertilizer has a significant effect on fighting for "three peaches". Generally, the application of urea Stanley compound fertilizer is 20-30 kg. For cotton fields with poor soil fertility, less base fertilizer and weak growth, it can be applied early, when the cotton plants bloom more than 80%, and when one or two young peaches are sitting, the topdressing method is appropriate.

4, supplement application of topping fertilizer: supplement application of topping fertilizer mainly to prevent cotton deficiency and premature aging in the late stage, promote plant steady growth, enhance disease resistance, insect resistance, anti-premature aging ability, and strive to multi-gate autumn peach and increase the weight of the bell. Generally, the top dressing is carried out before and after topping. For the nitrogen-deficient or prematurely-deficient cotton field, spray 1% urea solution per acre for 50-75 kg, once every 5-7 days, and spray 2~3 times. For the phosphorus-deficient, potassium-producing or late-growing green cotton field, spray 0.2% potassium dihydrogen phosphate solution every 7 to 10 days, and spray 2 or 3 times to reach the later stage without yellow leaves, no leaves, no premature aging, high yield. High quality purpose.

Fourth, pruning technology

1. Defoliation: When the first fruit branch appears, the leaf branches below the first fruit branch are removed in time, and the main stem leaves are retained to provide organic nutrients to the roots, which are called de-leaf branches or smears. Defoliation is one of the means to control the high yield of cotton. The cotton plants with weak seedlings and lack of seedlings can not leave the leaves, and then they will stretch their hearts. The leaves are removed at the beginning of the bud. Generally, the medium-ripe varieties with loose plant types need to be leaf-leaved, and the early-maturing varieties with compact plant types may not perform this work.

2, topping: topping can eliminate the top advantage, adjust the photosynthetic products in a balanced distribution in each organ, increase the proportion of nutrient distribution in the lower organs, strengthen the transport of assimilation products into the roots, enhance root vigor and the ability to absorb nutrients, In turn, the bell rate is increased.

3, playing the heart: playing the heart is to hit the top of the fruit branches. The edge of the heart can control the lateral growth of the fruit branches, improve the ventilation and light transmission conditions in the field, and help to increase the bell-forming rate, increase the boll weight, and promote precocity. In the production of cotton fields with sufficient fertilizer and water, the growth is relatively strong, and the density is relatively high. In the middle and late stages of the field management, the top of the field is beaten from the bottom to the top, and combined with the bell ringing condition, the lower part stays 2~3 fruit sections, the middle stays 3~4 fruit sections, the upper part can be played according to the local first frost period.