杂交棉稀播条件下冠层结构特征及产量变化研究

【目的】以杂交棉高产高效生产为目标,通过降低杂交棉用种量,探讨杂交棉冠层及产量的形成规律。【方法】以新陆早43号和鲁棉研24号为材料,研究不同稀播密度对杂交棉冠层结构、光合特性及产量的影响。【结果】杂交棉密度降至10.5×104株/hm2时,通过发挥个体与群体协调增产优势,总铃数在150×104个/hm2左右,达到3 300 kg/hm2超高产水平;生育前期叶面积指数(LAI)、群体光合速率(CAP)上升快,冠层光吸收率高,光合产物积累多,提高了干物质生产能力和转化率,达到了增产增效的目的;在稀播密度下降到4.5×104株/hm2时,产量在2 700 kg/hm2以下,下降幅度达18.1%~21.7%。【结论】适当降低杂交棉的密度,发挥个体增产潜力,能够达到节本、高产、高效的目的。

Study on the Canopy Structure and the Yield of Hybrid Cotton at Low-Density in Xinjiang

【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/hm2 ultra-high levels at the density of 10.5×104 plants/hm2,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/hm2 levels at the density of 45 000 plants/hm2,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.