水稻种质资源光合与水分利用特性比较及聚类分析

Comparison and Cluster Analysis on Photosynthetic Characteristics and Water Usage Efficiency of Rice Germplasms

探讨水稻种资源的光合特性,并筛选出高光效水稻资源,为水稻种质资源遗传改良提供参考。对58份来自不同国家和地区的水稻种质资源的光合特性、水分利用效率(WUE)及叶绿素相对含量(SPAD)进行比较及聚类分析。结果表明,不同稻种资源间的光合速率(Pn)、气孔导度(C)和蒸腾速率(E)存在极显著差异,水分利用效率存在显著差异。光合特征前3个主成分的方差累计贡献率达95.31%。C、Pn、E为第1主成分主导因子,WUE和Pn为第2主成分主导因子,第3主成分主要由SPAD构成。聚类分析将58份稻种资源划分为7个类群,筛选获得第1、6类群9个高光合速率、高水分利用效率以及较高叶绿素相对含量种质资源,作为水稻高光效育种、抗逆育种的中间材料或配组亲本材料加以利用。

Photosynthetic characteristics(PC)of various rice germplasms were determined to identify high-efficient genetic resources for improvements on rice cultivars.In addition,the water usage efficiency(WUE)and chlorophyll content(SPAD)of 58 rice germplasms from various nations and regions were obtained for comparison and classification in a cluster analysis.The results showed that there were significant differences(P<0.01)in photosynthesis rate(Pn),stomatal conductance(C),and transpiration rate(E),as well as highly significant differences(P<0.05)in WUE,among the tested varieties.The 3principal components cumulatively contributed to the variances among the cultivars at 85.31%on C,Pn and E being the 1stprincipal component;on WUE and Pn,the 2nd;and,on SPAD,the 3rd.Based on Pn,WUE,and SPAD,the 58 germplasms were clustered into 7groups.As a result,Group 1and Group 6consisting of 9germplasms that showed high PC,WUE and SPAD were recommended for crossbreeding purposes.