Detailed explanation of the high-density cotton cultivation model with five rows per film
Management of cotton during the boll-opening stage focuses on "four skillful practices" (skillfully managing fertilizer and water, skillfully pruning, skillfully picking rotten bolls, and skillfully promoting ripening). 1. Skillfully manage fertilizer and water to promote nutrient translocation. First, foliar topdressing. For cotton fields where leaves lose greenness too early and show fertilizer deficiency and premature aging, spray 50-60 kg per mu of 1%-2% urea solution on the leaves to extend leaf...
** cotton, on the basis of the short-dense-early cultivation model, proposed high-density cotton cultivation, that is, increasing the theoretical density from about 13,000 plants per mu with four rows per wide film to about 16,000 plants. Practice with the high-density cultivation model has proved that its yield-increasing effect is significant, and it developed rapidly in cotton production in **. In 2002, the high-density planting area accounted for 69% of the cotton area. According to yield measurement surveys at all levels, under normal conditions, high-density cultivation generally increases unit yield by 10%-20% compared with four rows per film. In 2001-2002, the Agriculture Department of the autonomous region organized experts to conduct yield measurement and acceptance of high-density high-yield sites in southern and northern Xinjiang, and for two consecutive years the unit yield of the high-yield site with the five-rows-per-film model in Luntai County was the highest. In 2001, I was assigned by the Agriculture Department to work at a stationed point in Luntai County to promote the application of high-density cotton cultivation techniques. Here I introduce the five-rows-per-film cotton model for reference by colleagues.The five-rows-per-film high-density cultivation model adds one row in the middle on the basis of the original four rows per wide film (film width 1.4 m). Generally, after sowing, the film width is 110 cm, the spacing between film strips is 50 cm, and the plant spacing is 12.5 cm. In 2002, this model developed to 80.3% of the cotton sowing area in Luntai County, rapidly increasing Luntai County's cotton unit yield from 101 kg in 2000 to 118.9 kg in 2002, an increase of 17.7%, with a very significant yield-increasing effect.
On September 8, 2001, we investigated two high-yield fields in the Second Brigade of Harbage Township and the Forestry Team of Chedaya Township, with unit yields reaching 178.02 kg and 173.29 kg respectively. Both fields used the variety Zhongmian 35.
1. Investigation results
l. Regarding the actual number of surviving seedlings and boll formation in different rows, it is relatively obvious that the middle row (different from the third row) has slightly better seedling preservation and slightly poorer boll formation. Under normal conditions, the edge rows have good ventilation and light transmission and a high boll formation rate.
2. The fruiting branch node position of the edge rows is lower than that of the middle row; the fruiting branch height of the edge rows is greater than that of the middle row; plant height is greater in the edge rows than in the middle row; stem diameter is slightly greater in the edge rows than in the middle row; the two points of plant height ratio and stem diameter ratio are inconsistent between the edge rows and the middle row.
3. The average number of fruiting branches per plant is 7.65-9.35; the number of effective fruiting branches is 5.3-5.8; the proportion of effective fruiting branches to total fruiting branches is 69.29%-62.47%; the average number of bolls per plant is 6.05-5.95; the boll formation proportion on fruiting branches 1-3 is 54.11%-39.11%; the boll formation proportion on fruiting branches 4-6 is 30.12%-28.73%; the boll formation proportion on fruiting branches 7 and above is 15.89%-32.15%.
2. Investigation conclusions
1. The five-rows-per-film high-density cultivation method is convenient and feasible, and it is one of the effective models for creating high cotton yields in our region.
2. To achieve a high yield of 170 kg with the five-rows-per-film high-density cultivation method: (1) plant height should be controlled at 45-55 cm. (2) The average number of fruiting branches per plant should be 8-9, and the number of effective fruiting branches should be 5.3-5.8. (3) The average number of bolls per plant should be 6. (4) The average boll formation rate on fruiting branches 1-3 should be 46.62%, the average boll formation rate on fruiting branches 4-6 should be 29.43%, and the average boll formation rate on fruiting branches 7 and above should be 24.02%.
3. Key points of the model
1. Attention should be paid to improving the retention rate of the edge rows and solving the problem that too much soil covering on the edge rows affects the emerging seedlings and their growth and development. At the same time, attention should be paid to improving the boll formation rate of the middle row.
2. The number of fruiting branches retained should not be too high. A target number of fruiting branches that is too high will lead to excessive vegetative growth, hollow middle sections, or late maturity.
3. When topping, it must be done correctly and must not be too light (such as pinching). If topping is too light, the last 1-2 fruiting branches have not yet fully developed, and the endogenous hormones produced at their tips cannot normally stimulate fruiting branch development. After topping, there is also no normal supply of endogenous hormones from the plant apex, which often causes the last 1-2 fruiting branches to form ineffective fruiting branches, affecting the yield structure and the achievement of the target.
4. The boll formation rate of fruiting branches is distributed in a pyramid shape from bottom to top.
5. Ensure the implementation of various cultivation measures so that the proportion of effective fruiting branches remains above 66%.