摘要： 对夏谷品种鲁谷10号3种密度条件下群体光合速率的研究表明，生育期间群体光合速率的变化都呈单峰曲线型，峰值出现在开花期前后，从抽穗到灌浆初期维持较高的光合速率。但高密度条件下开花后群体光合速率衰减很快。开花期和灌浆后期对不同冠层器官光合贡献的分析表明，两个时期趋势相同，都以上三叶贡献最大，中部三叶次之，下部叶较低，茎鞘只占5%左右，穗部表现为呼吸消耗，且消耗总光合比重趋于上升。根据研究结果提出了鲁谷10号亩产400kg以上的群体光合指标为，开花期群体光合速率应达31µmol·m^-2·s^-1以上，以后应维持在较高水平，至成熟期仍应达12µmol·m^-2·s^-1左右。还探讨了群体光合速率与产量构成因素的关系

关键词: 夏谷, 群体光合速率, 密度, 器官, 光合贡献

Abstract: Three different population densities of summer sowing foxtail millet(Lugu 10)were studied in two years. The results indicated that the changes of canopy photosynthesis rates(CPR)showed single peak curves,the peak of CPR was in flowering stage, the CPR from boot stage to the beginning of seed filling stage all kept high photosynthesis rate, but the CPR after flowering stage decreased very quickly in the condition of high density. The CPR contribution of different layers to organs total CPR were studied in the flowering and late seed-filling stages.The results showed that the CPR contribution of upper three leaves was the biggest,that of middle three leaves was the second,that of lower leaves was smaller, the contribution of stems and sheathes only accounted to 5% or so, the ears expressed respiration consuming, the proportion of consuming total CPR was tended to increase. Based on the research results, the criteria of photosynthesis were raised for the yield over 400 kg/mu of Lugu 10:CPR at the flowering stage should be over 31 µmol·m^-2·s^-1 and should keep in higher level from then,CPR at mature stage should keep 12µmol·m^-2·s^-1.The relationship between CPR and yield components also were discussed.

Key words: Foxtail millet(Setaria italica Beauv.), Canopy photosynthesis rate(CPR), Density, Organ, Contribution of photosynthesis

中图分类号: 

• S515.01