Study On The Flowering Function Of Soybean SVP Homologous Genes

Soybean is an important grain and oil crop,improving soybean yield has always been the goal of breeders.The flowering period is one of the important agronomic traits that affect soybean yield and ecological adaptability.The SHORT VEGETATIVE PHASE(SVP)gene and AGAMOUS-LIKE24(AGL24)gene in Arabidopsis have high similarity and have been proven to be important flowering regulatory factors.However,the study of their homologous genes on soybean flowering function is still unclear.This study utilized homologous alignment and evolutionary tree analysis to identify two SVP homologous genes and one AGL24 homologous gene in soybean.The three genes were named GmSVP01(Glyma.01G023500),GmSVP02(Glyma.02G041500),and GmSVP06(Glyma.06G095700)based on their respective chromosomes.The functions of GmSVP01,GmSVP02 and GmSVP06 in regulating flowering in soybean were elucidated by means of Arabidopsis complement experiment,genetic transformation,quantitative polymerase chain reaction,CRISPR/Cas9 genome editing and other techniques.The specific research results are as follows:1.The spatiotemporal expression analysis found that the GmSVP01/02/06 gene in soybean was highly expressed at the top bud and lateral buds,and the expression level in the vegetative stages is generally higher than that in the reproductive stages,indicating that the three genes mainly play a role in the vegetative stages and may be related to tissue differentiation and flowering regulation.2.The GmSVP01 and GmSVP02 genes can complement the early flowering phenotype of Arabidopsis svp mutants,indicating that soybean GmSVP01 and GmSVP02 have a conserved function of inhibiting flowering in Arabidopsis.By combining stable soybean transformation technology,Gmsvp01/Gmsvp02 homozygous double mutants and GmSVP01 overexpressed plants were obtained.Under long-term conditions,there is no significant difference in the flowering period between the Gmsvp01/Gmsvp02 double mutants and the wild-type,while the GmSVP01 overexpressed plants can significantly delay the flowering period.It is speculated that the GmSVP01 and GmSVP02 genes may have a dose-dependent inhibitory effect on flowering.Further research has shown that GmSVP01 inhibits soybean flowering by inhibiting the expression of Gm FT2 a,Gm FT5 a,and GmSOC1 a.3.By observing the flowering phenotype of soybean Gmsvp06 homozygous mutant plants under long-term sunlight conditions,it was found that GmSVP06 can delay soybean flowering and is mainly achieved by inhibiting the expression of Gm FT2 a,Gm FT5 a,GmSOC1 a,and GmSOC1 b.4.Combining the resequencing data of soybean natural resources,haplotype analysis was conducted on the GmSVP01,GmSVP02,and GmSVP06 genes in soybean.The results showed that both GmSVP01 and GmSVP06 genes were selected during the evolutionary process;Further results of flowering association indicate that GmSVP01 and GmSVP06 have the function of regulating soybean flowering,while the GmSVP02 gene seems to have not been selected during the evolution process.In summary,this study demonstrates that the GmSVP01/02/06 gene has the function of regulating flowering,providing reference for further analyzing the functions of SVP and AGL24 homologous genes in different species;And preliminarily analyzed the molecular mechanism of its regulation of flowering,further improving the soybean flowering regulation network;At the same time,the natural variation of soybean GmSVP01/02/06 was excavated,its providing a theoretical and practical basis for soybean molecular breeding.