Genetically modified cotton - insect-resistant cotton

The rapid spread of transgenic insect-resistant cotton has effectively controlled the damage of cotton bollworm. However, due to the short production period of insect-resistant cotton, the majority of cotton farmers lack sufficient understanding of its growth and development characteristics. The traditional cotton cultivation techniques are used in management, and the good methods of good varieties are not matched, so that the potential for increasing yield of insect-resistant cotton cannot be fully realized. In order to improve the scientific cotton-planting technology level of the majority of cotton farmers, according to the results of trials and demonstrations, simplified cultivation techniques for transgenic insect-resistant cotton were summarized, and standardized transgenic cultivation techniques were used to guide the production of transgenic insect-resistant cotton to achieve high-quality, high-yield production and increase efficiency. 1. Applying base fertilizer, chemical weeding transgenic insect-resistant cotton seedlings have a weak growth potential at the bud stage, so it is very important to lay a good foundation for fertility. Insect-resistant cotton is more sensitive to potassium, re-application of base fertilizer to increase potassium on the basis of phosphorus, combined with site preparation, the general cotton Mushi organic fertilizer 2500 kg, application of high-quality fertilizer 15 kg of ammonium phosphate, urea 5 kg, potassium chloride or Potassium sulfate 10-15 kg. The amount is sufficient and the nutrient is fully distributed to ensure that the cotton plants grow robustly and enhance the expression of insect resistance. Chemical weed control is an economic and effective control technology for weeds in cotton fields. Approximately one week before sowing, a rotary weeding cotton field was used and a herbicide was applied at one time. Herbicides can also be divided into sub-divided areas. After the first sowing, herbicides are sprayed in narrow rows, and immediately after spraying, they are coated to prevent weeds in the film. After the second time the cultivation of the cultivated soil in the big line is completed, according to the occurrence of weeds, the cotton fields dominated by grasses and weeds can be sprayed on a steady basis or can be harvested. The cotton fields dominated by broad-leaved weeds can be oriented in large banks. Spraying a non-invasive herbicide without trace or grass-grow, complementing the advantages of artificial cultivation and weeding. The above two methods can be flexibly selected based on actual conditions such as the occurrence of weeds, cotton planting area, and labor conditions, and weeding effects can be obtained. 2, rational close planting, simplified pruning insect-resistant cotton generally fast mid-term development, but the late growth is weak, easy to premature aging. Therefore, it is very important to plant the plants in a reasonable and close-packed way to give full play to the advantages of increasing the production of the group's best ringing period. Appropriate planting density depends on the variety characteristics, soil fertility and management level. Reasonable planting density, combined with timely and appropriate amount of control, can effectively control the occurrence of redundant leaf axillary buds, so pruning can be greatly simplified, good cotton field should be wiped leg, topping, general cotton field wipes legs can make traditional The "five-step pruning" is simplified to one or two steps, saving labor and labor. 3, chemical regulation, water and fertilizer synchronization after flowering into the peak of flowering fast, Chengling concentration is an important characteristic of transgenic insect-resistant cotton. Therefore, for insect-resistant cotton, the time for top-dressing should be advanced. From the re-application of conventional cotton, the flower-bell fertilizer should be advanced to the early flowering stage, the water-fertilizer should be synchronized, and the competition for water and fertilizer needs to be created by relieving the construction of high-yield plant type and rapid flowering and bolling. At the same time, full use of chemical and chemical control on the dual effects of vegetative growth inhibition and reproductive development promotion, synchronization and water and fertilizer synchronization. Generally, 15 to 20 kilograms of urea and about 45 cubic meters of water are pumped up per hectare in the cotton field, and the control and promotion of control and promotion are combined under the control of water and fertilizer control. Foliar sprayed with 0.5% potassium dihydrogen phosphate, 1% urea solution 2-3 times, to prevent late aging, especially reduce the incidence of red stem blight. 4. Intertidal furrow irrigation, saving water and water is one of the most active factors affecting the growth and development of cotton. Both drought and flooding can cause a significant reduction in cotton production. Insect-resistant cotton blossoms quickly and becomes concentrated in bolls. The critical period of water requirement during the middle growth period is particularly sensitive to moisture. Water shortage can easily lead to premature aging, the rate of boll formation is reduced, and the boll light clothing is low. However, too much water can also cause significant negative effects, such as high-intensity rainfall in late July 2003, saturating the water content of the cotton fields, and even causing water damage, resulting in verticillium wilt and physiological diseases. Therefore, in combination with cultivating soil, dredging the ditch, changing large sluice and long sluice to flood irrigation, it is necessary to control the amount of irrigation water, which can not only save water, but also guarantee uniform irrigation, and the narrow line can maintain the soil environment suitable for root development. . According to tests, irrigation efficiency is about 45 cubic meters per mu, and the irrigation efficiency is the best. Increasing the irrigation volume to 90 cubic meters will induce prosperous growth, and the increase in production and irrigation efficiency will decrease. 5, chemical ripening, concentrated picking cotton ethephon chemical ripening is one of the most effective measures to promote early maturation. According to the characteristics of growth and development of transgenic insect-resistant cotton, from July to late July is the key period for concentrating on bolling. By mid-September, the vast majority of cotton bolls have been developed for more than 50 days, which has reached the basic requirements for chemical ripening. This part of the boll has the effect of promoting development, accelerating maturation, increasing the boll weight and increasing the lint. 700-800 times per acre spray 20 kg of ethylene solution, the whole plant uniform spray. As the temperature is higher and the efficacy is faster at this time, the boll opening peak can be entered after 1 week and the basic harvesting is completed in early October. The mobilization of centralized collection can reduce the number of picking and drying operations and labor, early maturing and early harvesting, realizing high-quality and high-yield cotton, and wheat sowing in high-yield period to improve the overall economic efficiency.