Abstract:Longan fruits of 19 varieties introduced to Guangzhou were compared and evaluated in the characteristics of fruit quality. The results showed that there were no significant differences in most of the apparent characteristics among the varieties except for the fruit shape and flesh texture, and there were also some correlations between some of the characteristics. There were significant negative correlations between fruit size and total soluble solids (TSS) content, as well as between skin thickness and TSS. The fruits with thin skin, thick pulp or with the shape of oblate spheroid in transverse were positively correlated to the high edible rate. The 19 varieties were classified into 3 clusters using a hierarchical clustering method and evaluated according to the 8 quality indices. By performing a factor analysis based on the principal component, the 8 quality indices were represented with 3 principal components (their cumulative contribution reached 88.27%). It was concluded that the simplified evaluation indices included mass per fruit, fruit shape index, edible and pulp thickness rate. Further more, the clustering results of 19 varieties according to the factor scores and the simplified indices were coincident with each other.