蓖麻高光效种质的筛选

Screening of Castor Germplasm with High Photosynthetic Efficiency

【目的】研究蓖麻不同种质的光合特性,为蓖麻高光效种质的筛选及利用提供参考。【方法】结合主成分分析与系统聚类分析等方法,对29份来自不同地区的蓖麻种质胞间CO_(2)浓度(Ci)、蒸腾速率(Tr)、气孔导度(Gs)、净光合速率(Pn)、叶片瞬时水分利用效率(WUE)和蒸腾效率(TE)6个光合参数综合评价,筛选出优异蓖麻种质。【结果】6个光合参数的变异系数范围为16%~35%。其中,Pn与Gs的变异系数最高、达35%;Ci的变异系数最低、为16%。相关性分析中,Pn与Ci呈极显著负相关,与Tr和WUE均呈极显著正相关。主成分分析结果表明,3个主成分可以解释6个光合相关参数的99.15%,3个主成分可称为光合因素、气孔因素和水分因素。光合参数聚类分析将29份蓖麻种质划分为4个类群。其中第Ⅱ类包括4个材料,占总材料数的13.79%,这些材料净光合速率最高,均超过整体材料净光合速率的平均值,且本类群中的Pn、Gs和Tr均处于较高水平。筛选出YSL-5、SD-21、A40-7、B11-1等4个材料作为适合育种需要的高光效蓖麻种质。【结论】Pn高、Gs大、WUE相对较高的一类种质可作为蓖麻高光效品种选育的中间材料加以利用。

【Objective】The research of photosynthetic characteristics of different castor germplasms was carried out to provide references for the selection and utilization of castor germplasms with high photosynthetic efficiency.【Method】Based on principal component analysis and cluster analysis,a comprehensive evaluation of six photosynthetic parameters including intercellular CO_(2) concentration(Ci),transpiration rate(Tr),stomatal conductance(Gs),net photosynthetic rate(Pn),leaf instantaneous water use efficiency(WUE)and transpiration efficiency(TE)of 29 castor germplasms from different regions were conducted to screen out excellent castor germplasm.【Result】The variation coefficients of the six photosynthetic parameters ranged from 16%to 35%.Among them,Pn and Gs were the highest at 35%,and Ci was the lowest at 16%.Correlation analysis revealed that Pn significantly negatively correlated with Ci and significantly positively correlated with both Tr and WUE.The results of principal component analysis showed that three principal components could explain 99.15%of the six photosynthesis-related parameters.These components were photosynthetic factor,stomatal factor and moisture factor.Cluster analysis based on photosynthetic parameters divided the 29 castor germplasms into 4 groups,of which Group II consisted of 4 materials(YSL-5,SD-21,A40-7,and B11-1),accounting for 13.79% of the total number of materials.These materials had the highest net photosynthetic rate,all exceeding the average net photosynthetic rate of the overall material,and the Pn,Gs and Tr in this group were all at a high level compared with those of other materials.Therefore,the four materials could be selected as castor germplasm with high photosynthetic efficiency suitable for breeding.【Conclusion】The castor germplasm with high photosynthesis rate,large stomatal conductance and relatively high leaf instantaneous water use efficiency can be used as intermediate material for breeding of castor variety with high photosynthetic efficiency.