Genome-Wide Association Analysis Of Traits Related To Phosphorus Efficiency In Wild Soybean Seedling

Soybean [Glycine max(L.)Merr.] is one of the important grains and oils.It provides rich protein and oil for human beings and is widely cultivated worldwide.However,Chinese soybean imports have increased year by year.Since most of the phosphorus is fixed in the soil and cannot be absorbed by plants,low phosphorus stress has become one of the main factors affecting soybean production.The combination of plant molecular improvement breeding and traditional breeding to improve the low phosphorus tolerance of plants is considered to be one of the most economical and effective methods to solve the problem of phosphorus deficiency in plants.Wild soybean(Glycine soja Sieb.et Zucc.)has rich genetic diversity and high stress resistance.It is of great significance to explore the low-phosphorus tolerance gene resources in wild soybean population.In this study,a wild population composed of 240 wild soybeans was used as the research material.Three batches of hydroponic experiments were conducted for phenotypic identification and analysis.The genome-wide association analysis of 7 traits related to low phosphorus tolerance was performed using 1,038,077 SNPs.The interval and function annotation of the identified stable associated SNPs loci are used to predict and analyze related candidate genes.The main results are as follows:1.Phenotypic variation of traits related to phosphorus efficiency at the seedling stage of wild soybeans: After phosphorus stress treatment,the dry weight of shoots,the fresh weight of shoots,the concentration of shoots of phosphorus,and the accumulation of shoots of phosphorus showed an overall downward trend,and the photosynthesis products of plants were more severe.Migration to the root system leads to an increase in the rootto-shoot ratio,and its phenotypic variation is mainly caused by genetic factors.The seven traits of the population(dry weight above ground,fresh weight above ground,dry weight root to shoot ratio,fresh weight root to shoot ratio,aboveground phosphorus concentration,aboveground phosphorus accumulation,and aboveground phosphorus utilization efficiency)all have extensive phenotypic variation,Showing a normal or nearly normal distribution,showing the characteristics of quantitative traits.2.Genome-wide Association Analysis of Phosphorus Efficiency Related Traits: The seven trait indicators related to phosphorus efficiency at the seedling stage of wild soybeans were combined with 1,038,077 high-quality SNPs for genome-wide association analysis.A total of 834 SNPs were identified that were significantly associated with related traits,and 57 SNPs were stably associated with related traits,mainly distributed on chromosomes 7,11,14,19,and 20.3.Prediction of candidate genes: Convert the physical location of the detected stable associated SNP site into the physical location of wild soybean,and search for candidate genes within 80 kb near each site,and a total of 179 candidate genes were found.Four candidate genes that may be related to phosphorus efficiency were finally selected,including guanine nucleotide exchange factor Gs070,auxin response protein Gs103,zinc finger protein Gs135,and ethylene response factor Gs182.