The Seedling technique of Cotton floating in Water

"Cotton floating Seedling Technology" is a new cotton planting technology developed by agricultural experts in Hunan Province. this technology uses porous polyethylene foam seedling tray as carrier and mixed substrate as support. The seedling tray containing cotton seeds is put into the nutrient liquid water nursery bed for cultivation, which has significant seed saving, labor saving, yield increasing and synergism, and the seed consumption is more than 40% less than that of conventional nutrition bowl seedling transplanting cotton. The labor consumption of raising seedlings and transplanting per mu is reduced by about 10. Cotton seedlings have developed root system, low Lignification, soft and elastic, not easy to break, strong vitality, neat and consistent growth. In the process of seedling transplanting, the root system damage is less, the slow seedling period is short, and the yield is 7-10% higher than that of seedling transplanting in nutrition bowl. The technology can be applied on a factory scale, and it is also suitable for farmers to make use of the empty flat in front and back of the house. in case of disaster weather, the seedling tray can be quickly moved indoors to avoid the risk of raising seedlings. According to the appraisal of experts, "Cotton floating Seedling raising Technology" occupies the international advanced level, is a major technological revolution in cotton production, and is of great value in popularization and application. The operating procedures are introduced as follows.

First, the preparation of seedbed. Choose leeward to the sun, easy to manage, near the cultivated land in the cotton field or the empty gap between the front and back of the house, the seedling bed is 1.1-1.2 meters wide, 20 centimeters deep and 2.1 meters long. Dig the seedbed with a hoe and tamp it around. The bottom of the bed is flat, pick up stones, sharp and hard plant roots and so on.

Second, the seedling bed should be covered with film. First, wet the seedbed around and the bottom with water, spread the film at the bottom of the seedbed and around it with a film of 0.006-0.01mm thick, so that the back of the film is close to the soil, and the film extends to cover the seedbed by 15 cm each. Test the water immediately after laying the film to check whether there is water leakage and whether there are air bubbles at the bottom of the film. If the film is leaking, you need to replace the film. If you find any air bubbles, you need to re-lay the film. Compacted with soil after testing the water.

Third, the matrix is loaded into the plate. Select a highly efficient mixed matrix, pour out the matrix and moisten it evenly with water, so that the water content of the matrix can reach 60% of its own weight (the hands are pinched into a ball, there is no running water between the fingers, and the backwardness spreads naturally). Pour the substrate evenly into the seedling tray and scrape it flat on the surface of the seedling tray with hands or bamboo or wood strips. Shake the seedling plate so that the substrate is tight and drop to 1-1.5 cm away from the disk surface, which is easy to sow.

Fourth, prepare the nutrient solution for raising seedlings. First prepare the mother liquid, use containers such as buckets or pots, about 5 kg of water for each bag of special fertilizer for raising seedlings, stir with hands or sticks, fully dissolve the fertilizer and pour it into the seedling pond, then rinse the bucket or basin repeatedly with clean water for 2-3 times. pour the rinsing water into the seedling pond together. After pouring the mother liquid into the seedling pond, quickly add enough clean water, each package of fertilizer into 150-200 kg of nutrient solution. Stir while adding water to make the fertilizer distributed evenly.

Fifth, sow seeds. The Yangtze River basin is usually sown from April 20 to May 5. 15 days before sowing, drying seeds for 5-6 hours a day for 3-4 days. Two methods of seed soaking can be adopted: warm boiling water and warm water. Soak the seeds in lukewarm water for 2 minutes, then immediately cool them to 45 ℃ with cold water for 3-4 hours, so that the cottonseed can fully absorb water. Soaking seeds in warm water can soak seeds in 30 ℃ warm water for 8-10 hours, and cottonseed can fully absorb enough water. After soaking the seeds, pick out the young ones floating on the surface of the water, take the sunken and full seeds, and select the undamaged, wormhole-free Jianzi to sprout. Drain the selected seeds and pack them in small plastic bags of no more than 500g each. After packing, fasten the mouth of the bag, cover or wrap it with thermal insulation materials such as straw, cotton-padded clothes or quilts, heat preservation and germination (about 30 ℃), and sow when the cotton seeds break their breasts or the buds grow half a grain of cotton seeds. One grain for each hole, sown in the center of the hole, with the bud tip facing down, so that the bud tip is facing the hole at the bottom of the hole. The sowing depth should be 1-1.5 cm. Press the seed gently with your fingers and be careful not to break the root tip. After sowing, cover with the substrate 1-1.5 cm thick, with the substrate flush with the surface of the seedling hole as the degree.

Sixth, seedbed management. Immediately after sowing, put the seedling tray into the seedling bed, or put it indoors first, wait for the seedling to come out neatly, put it into the seedling bed, and discharge 2 horizontally and 1 vertically. Immediately after placing the tray, spray carbendazim and other fungicides on the tray surface with a sprayer. Then cover the film, using plastic film small arch shed to raise seedlings. Cotton seedlings raised by water floatation are sown by sprouting, so there is a fundamental difference between nursery bed management and nutrient bowl nursery, which must pay special attention to high temperature sprouting. It usually does not rain before emergence, when the temperature is above 20 ℃, it is only covered in the morning and evening, covering time from 06:30 to 07:30 in the afternoon. On rainy days, the film must be covered, but the two ends of the arch shed should be open, and then the tuyere should be opened around the arch shed, so that there should be no fog and no water droplets in the film. After the cotton seedlings come out, when it doesn't rain, the lowest temperature of the day is higher than 18 ℃, you can not cover the film day and night, cover the top on rainy days, and ventilate all around. If there is a cold current, cover the film to keep warm, or move the seedling tray indoors. Remove the film thoroughly on a sunny day to avoid burning seedlings at high temperature. When the average temperature of the day is above 20 ℃, all the seedlings can be trained with plastic film. After 2 true leaves of cotton seedlings, the seedling rack can be raised to make the roots leave the nutrient solution on a sunny day, and the seedlings can be refined intermittently for 1-2 hours. In addition, according to the growth of cotton seedlings, we should spray Zhuangzhuangsu or medroxyamine as appropriate to control and prevent tall feet, as well as timely prevention and control of diseases and insect pests.

7. Transplanting of water-raised seedlings. The best transplanting seedling age is from 2 leaves and 1 heart to 3 leaves and 1 heart, about 1200 plants per mu, row spacing 1 meter, plant spacing 45-55 cm. It is best to choose cloudy days, light rainy days, sunny days should be transplanted in the morning or after 4: 00 p.m. When transplanting, take out the seedling tray, lift it up, hold the base of the cotton seedling stem with your hand, and gently pull it up, so as not to damage the root system and keep the root system intact. When transplanting, there is no need to dig trenches or holes, but directly transplant with a small hoe or shovel to stretch the root system and make the seedlings stand upright. Watering root water and living plant water in time after transplanting.