Study On The Yield And Efficiency Of Hybrid Cotton Under Transplanted And Low-Density In Xinjiang

Hybrid cotton has high yield and individual growth advantage etc. features, the yield of cotton was further improved with the hybrid cotton planted in Xinjiang. However, but some cotton regions were frost-free period short, the heat resources were limited, have severely restricted the advantages of hybrid cotton. Planting early with lower height, higher densities and Under-Mulch-Drip irrigation is the core of high yielding cultivation technology system of cotton with Large amount of seeds, significantly increase the cost of hybrid cotton cultivation, affecting the development of hybrid cotton production. In this paper, hybrid cotton transplanting Sparse and thin seeding of hybrid cotton were done, avoids the disadvantageous climatic conditions influence, through the thin seeding of hybrid cotton in order to reduce the use of seed quantity, give full play to the individual yield advantage of hybrid cotton. Two hybrid cotton cultivars, Xinluzao 43 and Lumianyan 24, were transplanting grown at low-density with Under-Mulch-Drip irrigation, studying the changes and relationship of the canopy structure, photosynthetic characteristics and yield of hybrid cotton. Below are the main results in this thesis:1. Some cotton regions were frost-free period short, the heat resources were limited, have severely restricted the advantages of hybrid cotton. Field experiment was conducted in Northern Xinjiang, studying the changes and relationship of the canopy structure, photosynthetic characteristics and yield of hybrid cotton. The results showed that the number of bolls per plant and boll weight increased at a transplanting density of 15000 to 45000 plant·hm-2. However, total boll number per area has decreased due to fewer plants. Compared to the control, traditional planting at higher density, lower leaf area index (LAI), higher canopy openness (DIFN), lower light absorption and lower canopy photosynthetic rate of transplanting cotton, maybe result in lower yield. Although the seedlings could save 33.3% at transplant density of 30000 plant·hm-2, the lint yield is similar both at the density of 30000 plant·hm-2 and 45000 plant·hm-2, about 2900 kg·hm-2. For transplanting cotton, the ahead process of growth and the flowers before frost increased by 20%. Therefore, in order to achieve stable yield the sparse transplanting could be useful in northern regions that has more disaster at seeding stage.2. Large amount of seeds were planted, significantly increase the cost of hybrid cotton cultivation, affecting the development of hybrid cotton production Study on the suitable planting density of high yield and High efficiency of hybrid cotton in Xinjiang. The results showed that the lint yield of hybrid cotton reached 3300kg·hm-2 ultra-high levels at the density of 105000 plants·hm-2 with the total number of bolls 150×104·hm-2 through individual and group coordinated production advantage. The leaf area index (LAI), canopy openness (DIFN) rising fast, higher light absorption and more photosynthesis product, the dry matter production capacity and conversion rate are improved, reaching the purpose of increasing yield and efficiency. However, the yield of hybrid decreased less than 2700 kg·hm-2 levels at the density of 45000 plants·hm-2, decreased rage up to 18.1-21.7%. It is obtained that saving cost, higher yield and higher efficiency by playing the individual advantage, at a properly the density of hybrid cotton.3. The bud number per plant and the weight of boll are higher of hybrid cotton at low plant density, however, the total boll number of hybrid cotton at the density 105000 plant·hm-2 and 165000 plant·hm-2 are more than at the density of 45000 plant·hm-2, For transplanting cotton, the flowers before frost increased, the lint yield is similar both at the density for 30000 plant·hm-2 and 45000 plant·hm-2, the former lower cost with seedlings, showing higher efficiency. At low density sowing conditions, hybrid cotton planting density 105000 plant·hm-2, achieved the purpose of increasing production and efficiency. So promote optimum density of hybrid cotton is 105000 plant·hm-2. It is reduced for planting costs through transplanting with low density of hybrid cotton, transplanting mechanized and factory seedling can reduce hybrid cotton transplanting costs.