| Melon( Cucumis melo L.) is one of the important international fruity vegetables and occupies a pivotal position in the summer fruits. With the improvment of people’s living standards and people loving melon, the demand of melon is increasing both at home and abroad. Therefore, the melon production rapidly developed and the area is expanding fast. Because of the rapid development of the melon industry, the frequency of appearing new varieties in the melon market is increasing year by year. The the practice of melon breeding showed that comprehensive characters level of two parental materials for hybridization should maintain maximum complementarity, but kinship should be far as possible for breeding new varieties. At present, breeders have a tendency to focus on using few parents in the process of melon varieties breeding, leading the kinship of bred varieties is more similar and having narrow genetic basis. Because melon breeding companies were small and loose, species management has failed to follow up effectively. Even some melon varieties failed to pass the identification in sale, so that the situation affected the legitimate interests of breeders. So clearing the genetic diversity of breeding materials and genetic relationship have become the important foundation of melon breeding work and it is necessary to establish the DNA fingerprint of melon variety to provide basis for kinship and authenticity identification of melon varieties in Chinese. The 269 melon materials were identified by 15 morphological markers and 52 CAPS markers in this experiment.Utilizing 15 morphological markers, the diversity indexes were ranged of 4.09 ~ 7.99, the average was 6.73 in the seven melon quality traits; the diversity indexes were between 7.77 and 8.07, the average was 7.97 in the eight melon quantitative traits. From the cluster analysis result, genetic similarity coefficients of 269 melons were between 0.75 and 0.97, the average was 0.84. Extracted 73 melons were used for the second cluster analysis, these melons could be classified into 3 categories at the genetic similarity coefficient of 0.82, they were 36 thick melons, 35 thin melons and two thick melons whose phenotypic traits were very similar.In the 52 CAPS markers, the number of cleavage points in tested materials were from 22 to 39. Clustering analysis indicated that the genetic similarity coefficients were between 0.32 and 0.99, the average was 0.69. The second cluster analysis was conducted by 73 melons, the genetic similarity coefficients were between 0.51 and 0.98. The 73 materials could be divided into 3 categories in the genetic similarity coefficient of 0.60, they were 38 thick melons, 1 thin melon whose name is Xin Shi-ji and 34 thin melons. Compared with morphological analysis in the field, the result was basically same, but molecular marker was more accurate.The separate fingerprint code was construsted for melon materials based on CAPS markers. 37 materials of fingerprint codes were not unique with the ratio of 13.75% for all the melon materials. Most of the experimental materials(86.25%) could be identificted by the methods of CAPS markers.269 melon materials were built two-dimensional codes by QR Code conversion tool. The two-dimensional codes including name, type, origin and CAPS fingerprint code of melon materials. |
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