（College of Horticulture，Hunan Agricultural University，Engineering Research Center for Horticultural Crop Germplasm Creation and New Variety Breeding，Ministry of Education，Changsha 410128，Hunan，China）
Abstract：In order to rationally utilize melon germplasm resources and select breeding parents，this study carried out genetic diversity analysis on 42 major traits of 164 accessions melon germplasm resources．The results showed that the mean values of diversity indices for 24 quality traits and 18 quantitative traits of 164
accessions melon germplasm resources were 0.86 and 1.90，respectively，indicating that quantitative traits had greater genetic diversity．There were complex interrelationship between each quantitative traits，among which single melon quality showed extreme significant positive correlation with fruit development stage，fruit
length，fruit width，flesh thickness，stem thickness，petiole length，petiole thickness，leaf length，leaf width，seed weights a thousand grains，and yield；central sugar content had extreme significant and positive correlation with the number of seeds per melon，while had extreme significant negative correlation with fruit development stage，fruit length，fruit width，flesh thickness，stem thickness，petiole thickness，and seed weight per thousand．The results of principal component analysis showed that the cumulative contribution rate of the first 3 principal components was 85.689%，containing most of the information on melon fruit trait indicators．The comprehensive scores of 164 accessions germplasm ranged from -2.792 to 5.614．Five materials with higher comprehensive scores were‘S24’（MT010），‘Xinyintian No.22’（MT112），‘PI-315401’（MT133），‘Zhenzhenghamigua’（MT028），and‘Wangwentiangua’（MT048）．The results of clustering analysis showed that when the Euclidean distance is 5，these 164 accessions germplasm could be divided into 5 class groups，including separately 69，62，7，23，and 3 accessions germplasm．Summing up the above，the tested melon germplasm resources had rich genetic diversity．
