Studies On Genetic Diversity And New Varieties Comparison Of Melon Germplasm Resource

This research is based on 94 melon germplasm resources,morphological cluster analysis according to survey the phenotypic traits,and combining the ISSR molecular marker technique,comprehensively on the genetic diversity of research;And 17 analyzed combining ability and heterosis of melon varieties,mainly the following conclusions:1.We investigated some agronomic traits of melon,including stem length,stem diameter,leaf area,resistance,fruit weight,fruit cross-sectional area,seed cavity size,pulp thickness,area yield,the skin color and sugar,according to the result of statistic phenotypic traits,build the cluster analysis tree.The results showed that in the genetic similarity coefficient of 7.53,94 melon materials could be divided into two groups: ? classes including 83 and 93 two long melon materials;? classes including the rest of 92 melon type relatively round materials.In the genetic similarity coefficient of 5.51,? class divided into three groups: Group A,including 31 small single fruit weight,fruit pulp thinner melon materials such as 1,2,7,8,45 and so on;Group B including 52 melon materials with the single fruit weight and the thickness of pulp in the middle type;Group C including the rest 9 melon materials with the biggest single fruit weight.2.ISSR molecular marker technology,in 51 pairs of primers we chose 21 pairs of effectively primers.Use the article 22 primers for PCR amplification,94 melon materials amplified 116 bands,including 70 polymorphic bands,the percentage of polymorphic is 60.3%,with the average of 5.27 bands.The highest polymorphic primer is 816 with the maximum PIC Value 0.903,the lowest polymorphic primer is 891,PIC Valule is 0.078.3.The average Nei's and Shannon value was 0.159 and 0.247,respectively.The result showed that,in similarity coefficient of 0.843,the 94 melon materials could be divided into four categories: Group ? including 53 samples such as 1,2,14,40,70,94 with white,green and black skin melon materials;Group ? including 15 yellow and green or yellow stripe melon materials such as 29,32,36,77;Group ? including 17 yellow or yellow miscellaneous green melon materials;Group ? including the other 9 white melon materials.4.We chose 17 melon materials from the 94 materials,through surveyed 8 agronomic traits in the field,for the comparison between the varieties.Analysis results showed that the average coefficient of variation of eight traits is 20.20%,the coefficient of variation was between 3.22-50.37%.the stem length had the largest coefficient of variation for 3.22%,and the fruit cross-sectional area had the lowest coefficient of variation for 50.37%.The analysis of heritability indicates,the fruit cross-sectional area,pulp thickness,seed cavity size,sugar content,leaf area and fruit weight have high broad-sense heritability,it is better to use superior breeding...