Research On Genetic Variation Identification Of Bingtang Sweet Orange Sprout Variety Series

Bingtang sweet orange is the key variety of orange in Hunan province.After years of variety improvement,a number of excellent bud sports has been emerged,which greatly improved the comprehensive quality of the orange.Due to the high genetic similarity of the bud sports variety,it is very difficult to identify the variety of the Bingtang sweet orange bud sports series varieties.The citrus seed industry has many problems such as mixed varieties,superior varieties being counterfeited,and the production of set of brand infringing intellectual property rights,which seriously damages the rights and interests of breeders.Accurate and effective identification of Bingtang sweet orange bud sports series varieties is helpful to the healthy and orderly development of the citrus industry.In this research,the series of Bingtang bud sports variety were used as experimental material.Through observation and analysis of their phenotypic traits,screened the core phenotypic traits,and specific molecular markers were developed to identify the series of Bingtang sweet orange bud sports varieties by wholegenome resequencing technology.The results are as follows:1.Phenotypic observation of 8 Bingtang sweet orange and 45 other main citrus cultivation,preliminary identification of Bingtang sweet orange series varieties.According to《Guidelines for the conduct of tests for distinctness,uniformity and stability—Citrus》,87 traits of citrus varieties were focused on to determine the specific phenotypic traits of citrus varieties.The results showed that the phenotypic observation could distinguish pomelo,mandarins and orange,but the Bingtang sweet orange series varieties were clustered together.The phenological of the eight Bingtang sweet orange series varieties were similar,and the differences phenotypic were mainly focus on leaf and fruit characters.Combined with principal component analysis,11 core traits,such as leaf shape,fruit shape and peel color,were screened out,which could identify some Bingtang sweet orange varieties.2.Population genome was constructed based on citrus genome resequencing data.with personalized bioinformatics analysis,developed the SSR,SV and Indel markers.(1)A total of20,416 SSR loci were obtained,and dinucleotide base combinations had the most tandem repeats.There were 9,497 SSR loci per genome,accounting for 46.52% of all SSR loci.Sexonucleotide repeats were the least,accounting for only 1.28% of all repeats.One out of 50 pairs of SSR markers could discriminate red meat sugar orange.(2)We constructed part of the population genome of orange varieties,and 4 of the 20 pairs of SV markers were designed to identify sugar orange varieties from the 21 main varieties.(3)An average of 710,042 Indel variation sequences were generated for each sugar orange sample,and most of the variation ranged from 1-10 bp.Among 100 pairs of Indel markers,6 pairs of markers were selected to identify 8 Bingtang sweet orange varieties.In conclusion,we can preliminarily identify the variety of the Bingtang sweet orange bud variation through phenotypic traits,and develop 11 pairs of molecular markers to identify the variety of Bingtang sweet orange bud sports series variation.By annotating the mutation sequences,it was found that most of the amplified sequences were located between uncharacterized genes.