Objective: The purpose of this program is explore the formation rule of the yield and the canopy structure of hybrid cotton at low density and with less seeds to seek high yield and efficiency. Method: Two hybrid cotton cultivars, xinluzao 43 and lumianyan 24, were grown under-mulch-drip irrigation to study various low-densities' influence on the canopy structure, photosynthetic characteristics and the yield of hybrid cotton. Result: The results showed that the lint yield of hybrid cotton reached 3 300 kg/hm 2 ultra-high levels at the density of 10. 5*10 4 plants/hm 2, through individual and group coordinated production advantage. The leaf area index LAI, canopy openness (DIFN) rising fast. The higher light absorption and the more photosynthesis products will be, which contributes to the dry matter production capacity and conversion rate, thus helping reach the purpose of increasing yield and efficiency. However, the yield of hybrid decreased less than 2 700 kg/hm 2 levels at the density of 45 000 plants/hm 2, decreased rage up to 18.1%-21.7%. Conclusion: The aim of saving cost, improving the yield and efficiency can be actualized by exerting individual potential and by relatively reducing the density of hybrid cotton.
