| Sweet potato(2n=6x=90)is hexaploidy plant.Sweet potato is widely planted because of its strong resistance and wide adaptability,and it’s an important food crop in China.Existing cultivated sweet potato varieties have a narrow genetic background and close genetic relationships.There is an urgent need to widen the genetic diversity of sweet potatoes.In this study,120 sweet potato germplasm resources were used as research materials.The genetic diversity of sweet potato was analyze dusing cpSSR,and the fingerprint of sweet potato was constructed.TRAP markers were also constructed in this study,which is used to analysis of the application value of TRAP markers in sweet potato breeding.The purpose of this study is to provide theoretical basis for identification and kinship differentiation of sweet potato germplasm resources,and to provide guidance for parent selection of sweet potato hybrid breeding.The main results are summarized as follows:1.By designing 19 pairs of cpSSR primers and using the genomic DNA of sweet potato varieties Eshu 11 and Fucaishu 18 as templates,11 core primers were selected.A total of 43 bands were amplified in 16 leafy sweet potato materials,of which 33 were polymorphic bands.On average,3 polymorphic bands were ampli fied per primer pair,and the percentage of polymorphism was 76.74%.And a total of 58 bands were obtained from 104 sweet potato materials,with 47 polymorphic bands.The average number of amplified bands per single primer was 5.27,and the average polymorphism percentage was 75.18%.120 sweet potato varieties showed rich diversity in 11 pairs of primers,indicating that the primers selected in this study can effectively distinguish test materials and can be used for identification of sweet potato germplasm resources.2.The amplification of 11 pairs of primers in sweet potato material was analyzed,and the genetic diversity of 16 leafy sweet potato varieties and 104 sweet potato varieties were calculated.The genetic distance between 16 leafy sweet potato material was 0.0912 ～ 0.5067,the average genetic distance is 0.2301.Whe the coefficient is 0.74,16 sweet potato varieties can be divided into four groups.The amplification results of 104 sweet potato varieties were analyzed.The genetic distance between each variety was 0.0386 ～ 5.2723,and the average genetic distance was 0.2201.When the genetic coefficient was 0.73,the 104 sweet potato varieties were divided into 5 groups.3.Multi-factors were integrated to construct the fingerprint of sweet potato ger mplasm resources.Fingerprints of 16 leafy sweet potato varieties were constructed using 11 pairs of primers.Two pairs of primers were selected from 11 pairs of primers,and fingerprints of 104 sweet potato varieties were constructed.4.TRAP primers were developed based on the disease resistance genes of sweet potatoes.Eshu 11 and Ezishu 13 were selected to analyse TRAP primers.And sweet potato TRAP labeling reaction system was established The TRAP marker results showed that it has higher application value in sweet potato identification,important trait markers,and provided a reference for the TRAP marker to guide the selection of parents for sweet potato resistance breeding. |
