Genetic Mapping Of Key Genes Resisting Seed-shatterring In Green Flower Buckwheat

Fagopyrum esculentum M.,also known as Common buckwheat,belongs to the Polygonaceae Fagopyrum Mill crop.It is one of two cultivated buckwheat.It has a long history of cultivation and a wide range of cultivation.Because of its good nutrition and health value,common buckwheat is spread and promoted as a green food.Common buckwheat is easy to fall and cause huge yield loss during harvesting period,which reduces farmers’enthusiasm for planting common buckwheat and hinders the development and promotion of common buckwheat production.Therefore,the exploration of common buckwheat fall control genes is against the The cultivation and the increase of common buckwheat production are of great significance.Because the sequencing and splicing of the buckwheat genome have not yet been completed,the lack of annotation of the buckwheat genes has caused difficulties in the development of molecular markers.With the development and widespread use of high-throughput sequencing technology,the transcriptome of common buckwheat was sequenced based on the high-throughput sequencing technology,and the sequencing results were analyzed to develop common buckwheat primers,making it possible to locate genes of important importance in buckwheat.may.In this experiment,SSR primers and In Del primers were developed by sequencing the transcriptome of two varieties with large differences in seed-shattering properties.In the experiment,anti-seeding green flower buckwheat and buckwheat white buckwheat（Ukraine daliqiao）were used as parents.The diameter of the pedicel,pedicel pull and chlorophyll content were measured,and the anatomical observation of the cross-section of the parent pedicel was performed.Count the flower color of the mapping group F₂,determine its pedicel pull,and analyze the results of the observed agronomic traits.Combined with the genetic map to preliminary locate the key genes of seeding,the results are as follows:（1）Analysis of agronomic traits:Analyze the pedicel diameter and pedicel pull between the two parents.It is found that the green flower buckwheat stalk is thicker than the Ukrainian daliqiao,showing a very significant difference,and the pedicel pull shows the same trend.It was found that the content of chlorophyll a,chlorophyll b,carotenoids and total chlorophyll in green flower buckwheat was significantly higher than that of white flower buckwheat.Cross-sectioning of the parent flower stalk revealed that the number of vascular bundles in the green flower buckwheat stalk was larger than that in UD.More in buckwheat.The flower color of the F₁population is all white flowers,which conforms to the genetic laws of quality traits.The statistical results of the flower color of the F₂ population show that white flowers:green flowers=4.1:1;statistical analysis of the pull force of the flower stems of the F₂ population shows an approximately normal distribution of the pull value,and it is speculated that the buckwheat seed-shattering is quantitative.（2）Development of common buckwheat SSR and In Del markers:using Premier3.0 software to analyze the sequencing results of common buckwheat transcriptome,118,448 Unigenes were obtained,and 20756 SSR sites were searched from it,and 13909 pairs were designed with specificity SSR primers were randomly selected from 324 pairs of EST-SSR primers.The developed primers were verified in different common buckwheat and tartary buckwheat varieties resources.A total of 142pairs of polymorphic primers were amplified in 205 pairs of primers,of which 36pairs amplified a single band and 136 pairs had more than one band,Statistical analysis of the verification results,using NTsys mapping,the 45 buckwheat varieties are divided into two major categories of common buckwheat and tartary buckwheat（3）Construction of the genetic linkage map of common buckwheat:In Del search analysis was performed on the obtained transcriptome data using mutation detection software,43422 In Del sites were found from 118448 unigenes,and 320 pairs of In Del primers were designed and synthesized randomly.A total of 205 pairs of polymorphic primers were screened in the parents（green flower common buckwheat and UD）using the designed and synthesized common buckwheat primers based on transcriptome data.Among them,105 pairs of SSR primers and 100 pairs of In Del primers,the ratios of polymorphism were all 31.3%.Using these 205 pairs of polymorphic primers to detect the genotypes of 170 single plants in the F₂ population,and to analyze the polymorphisms of these 205 polymorphic sites,a genetic linkage map containing 175 sites was constructed.The map has a total of 8 linkage groups,with a total coverage length of 1359.23 c M and an average map distance of 7.77 c M.Among the 175 markers located in the genetic map,132 markers showed partial segregation（P<0.05）.Among them,74 markers were biased towards white flower common buckwheat（UD）and 58 markers were biased towards green flower common buckwheat.BLAST alignment of 205 pairs of polymorphic primers with the common buckwheat genome sequence found that 194 pairs of primers were successfully anchored on 178 scaffolds,and 16 scaffolds were anchored by 2 to 3 markers.（4）Mapping of flower color control genes and preliminary QTLs:using flower color traits as morphological markers Fe.gf-1 and maps to map flower color control genes.As a result,Fe.gf-1 was located in the linkage group.On Group01,located between SWU＿Fe0220 and SWU＿Fe＿In Del181,the genetic distance between the two markers is 5.0c M,and it is located on chromosome 6 of the tartary buckwheat genome.The physical distance is about 2.61Mb.From this,six genes that may be related to the common buckwheat flower color genes were screened out.Candidate genes.Using the constructed genetic map and the phenotypic traits related to seed-shattering,the QTLs of seedlings in buckwheat were initially mapped.Seven QTLs were detected,which were located on the Group01,Group04,Group05,Group06,and Group07linkage groups to explain phenotypic variation.Between 7.9-16.6%.