高光效甘薯种质筛选及光合特性分析

本文旨在研究甘薯种质资源的光合特性。对23份来自不同地区的甘薯种质资源进行光合性状测定,通过统计分析、相关性分析、主成分分析和聚类分析的方法对23份种质资源7个光合指标进行综合评价,筛选出高光效种质材料。结果表明,23份甘薯种质的7个光合指标存在极显著差异（P<0.01）。7个光合指标参数的变异系数范围为7%~18%,其中,净光合速率与气孔导度最高,胞间二氧化碳浓度最低。相关性分析中,净光合速率与叶片瞬时水分利用效率、蒸腾效率呈极显著正相关（P<0.01）。主成分分析结果表明,光合因子、气孔因子与叶绿素含量3个主成分,方差累计贡献率达95.511%。聚类分析将23份甘薯种质划分为5个类群,其中第Ⅰ类群的7个光合指标综合表现突出,且净光合速率高,因此,第Ⅰ类群可作为适合育种需要的高光效甘薯种质。

Screening of High-light-efficiency Sweet Potato Germplasm and Analysis of Photosynthetic Characteristics

This article aims to study the photosynthetic characteristics of sweet potato germplasm resources. The photosynthetic characteristics of 23 sweet potato germplasm resources from different regions were determined. Seven photosynthetic indicators of the germplasms were comprehensively evaluated by statistical analysis, correlation analysis, principal component analysis and cluster analysis. The results showed that there were extremely significant differences in the seven photosynthetic indicators of the germplasms (P< 0.01). The coefficient of variation of the seven photosynthetic index parameters ranged from 7% to 18%. Among them, the net photosynthetic rate and stomatal conductance were the highest, and the intercellular carbon dioxide concentration was the lowest. In the correlation analysis, net photosynthetic rate was significantly positively correlated with leaf instantaneous water use efficiency and transpiration efficiency (P<0.01). Photosynthetic factor, stomatal factor and chlorophyll content were the principal components, and the cumulative contribution rate of variance reached 95.511%. The 23 germplasms were diviede into five groups by cluster analysis. Among them, the photosynthetic indicators of group Ⅰ showed outstanding comprehensive performance and high net photosynthetic rate. Therefore, group I could be used as the high-light-efficiency sweet potato germplasm suitable for breeding needs.