马铃薯褐化种质资源表型性状综合评价

Comprehensive evaluation of phenotypic traits of potato browning germplasm resources

通过遗传多样性分析、相关性分析、主成分分析、聚类分析对马铃薯褐化群体中60份种质资源表型性状进行综合评价,为选育抗褐变马铃薯新品种及生产利用提供理论依据。结果表明,14个描述性指标的遗传多样性指数在0.085~1.157,茎色的遗传多样性指数最大,8个数值型指标变异系数在9.46%~69.22%,褐化指数、褐化强度变化值变异系数较大。相关性分析表明,单株产量与生育期、单株块茎数呈极显著正相关,与主茎数呈显著正相关,褐化指数与褐化强度、褐化强度变化值呈极显著正相关,与煮后变褐值呈极显著负相关。采用主成分分析确定了8个主成分因子,累积贡献率为69.785%。聚类分析将60份种质资源划分为5大类,其中第Ⅰ、第Ⅱ类属于高抗、抗褐变种质,可以用于抗褐变材料选育的亲本材料;第Ⅳ、第Ⅴ类属于易褐变、严重褐变种质,可以作为褐变机制的研究材料。研究结果可为马铃薯抗褐变新品种选育和遗传改良提供一定参考。

A comprehensive evaluation of phenotypic traits of 60 potato germplasm resources in browning population was conducted through genetic diversity analysis,correlation analysis,principal component analysis,and cluster analysis,providing theoretical basis for the breeding and production utilization of new potato varieties resistant to browning.The results showed that the genetic diversity index of 14 descriptive indicators ranged from 0.085 to 1.157,with stem color having the highest genetic diversity index.The coefficient of variation of the 8 numerical indicators ranged from 9.46%to 69.22%,and the variation coefficients of browning index and browning intensity were relatively large.Correlation analysis showed that the mass of individual tubers was highly significantly positively correlated with the growth period and number of tubers per plant,and significantly positively correlated with the number of main stems.The browning index was highly significantly positively correlated with the browning intensity and the change in browning intensity at 4℃for 24 hours,and significantly negatively correlated with the browning value after cooking.Principal component analysis identified 8 principal component factors with a cumulative contribution rate of 69.785%.Cluster analysis divided the 60 germplasm resources into 5 major categories.The I and II categories belonged to high resistance and browning resistant germplasm,which could be used as parental materials for breeding anti browning materials.Class IV and V belonged to germplasm that was prone to browning and severely browning,and could be used as research materials for browning mechanisms.The research results of this experiment could provide some reference for the breeding and genetic improvement of new potato varieties with resistance to browning.