Phenotypical and gene co-expression network analyses of seed shattering in divergent sorghum(Sorghum spp.)

Sorghum[Sorghum bicolor(L.)Moench],a multipurpose C4 crop,is also a model species of the Poaceae family for plant research.During the process of domestication,the modification of seed dispersal mode is considered a key event,as the loss of seed shattering caused a significant increase in yield.In order to understand the seed shattering process in sorghum,we further studied eight previously identified divergent sorghum germplasm with different shattering degrees.We described their phenotypes in great detail,analyzed the histology of abscission zone,and conducted a gene co-expression analysis.We observed that the abscission layer of the most strong-shattering varieties began to differentiate before the 5-10 cm panicles development stage and was completely formed at flag leaf unfolding.The protective cells on the pedicels were also fully lignified by flowering.Through the weighted gene correlation network analysis(WGCNA),we mined for candidate genes involved in the abscission process at the heading stage.We found that these genes were mainly associated with such biological processes as hormone signal transmission(SORBI_3003G361300,SORBI_3006G216500,SORBI_3009G027800,SORBI_3007G077200),cell wall modification and degradation(SORBI_3002G205500,SORBI_3004G013800,SORBI_3010G022400,SORBI_3003G251800,SORBI_3003G254700,SORBI_3003G410800,SORBI_3009G162700,SORBI_3001G406700,SORBI_3004G042700,SORBI_3004G244600,SORBI_3001G099100),and lignin synthesis(SORBI_3004G220700,SORBI_3004G062500,SORBI_3010G214900,SORBI_3009G181800).Our study has provided candidate genes required for shedding for further study.We believe that function characterization of these genes may provide insight into our understanding of seed shattering process.

Formation Mechanism and Occurrence Law of Pod Shattering in Soybean:A Review

Seed shattering refers to the phenomenon in which the pods split along the abdominal and back sutures before the crop is received,so that the seeds are spread.Seed shattering is vital to the reproduction of their offspring in wild plants,but it is also the main cause of crop yield loss reason.Pod-explosion resistance is a complex process of physical and physiological and biochemical reactions.Soybean seed shattering phenomenon is widespread,which severely restricts the development of soybean industry.Seed shattering(pod cracking or fruit dropping)is essential for the reproduction of its offspring in wild plants,but it is also the main cause of crop yield loss.This article analyzes the morphology and structure of pods related to seed shattering from the morphology of pods.On the basis of the regularity of the occurrence of seed shattering and the summary of phenotypic index identification methods,physiologically introduced the regulation mechanism of key enzymes and endogenous hormones on seed shattering.The localization,labeling and cloning of seed shattering genes are introduced in molecular biology.The study focused on reviewing the latest advances in the research on soybean seed shattering characteristics,and discussed with the research results of related crops.Finally,the research and application of soybean seed shattering resistance were prospected for several aspects.