Abstract:In this study, phenotypic diversity and classification of 212 aceessions of garlic germplasm in China were studied based on morphological traits by methods of clustering, principal component analysis, and correlation analysis. The results showed that the garlic germplasm in China presented a wide diversity from all traits. The five-grade classification method for each quantitative trait was brought forward. The results of clustering and principle component analysis indicated that clustering factors were mainly from qualitative traits. To avoid the overrating effect from qualitative traits, eight important quantitative traits related to bulb yield were evaluated. Principal component analysis showed the cumulative contribution proportion of the first three components was up to 74.83% and three traits (bulb weight, bulb diameter and clove number) were included in the first components which could be the most important traits affecting bulb yield. Correlation analysis suggested that bulb yield was significantly related with seven of eight characteristics except clove back width, and the most highly related with bulb diameter and bulb weight. All accessions of garlic germplasm were divided into 6 groups according to yield and the analysis of principal coordinates. Moreover, three accessions yielded above 15×103 kg ha-1 were selected out.