Characterization and genetic mapping of a novel recessive genic male sterile gene ms305 in maize (Zea mays L.)

Abstract

The male sterility system shows tremendous value for the long-term utilization of hybrid crop breeding. In this study, a male sterile mutant, K305ms, was derived from the M3 progeny of maize (Zea mays L.) inbred line K305 exposed to 60Co-γ irradiation. Male sterile K305ms plants did not show any obvious differences from their sibling male fertile plants (K305F) during the vegetative stage, but failed to produce functional pollen at the reproductive stage. Microscopic observations determined that the dyads and tetrads from the pollen of K305ms plants developed abnormally, and subsequently the microspores were shriveled. Genetic analysis indicated that the male sterility of K305ms was controlled by a single recessive genic gene. Gene mapping showed that the responsible gene was located between two simple sequence repeat markers on chromosome 2L in a region of 10.3 cM, bnlg469b and bnlg1940, with genetic distances of 2.9 and 7.4 cM, respectively. According to the microscopic and mapping characteristics, our results showed that this gene was distinguishable from all other reported male sterile genes in maize, and it is temporarily designated as ms305. The linkage map in this study will provide a useful fundamental basis for molecular marker-assisted selection as well as for further map-based cloning of ms305.

Male sterile 305 Mutation Leads the Misregulation of Anther Cuticle Formation by Disrupting Lipid Metabolism in Maize

“…K305 male sterility plant (K305ms, ms/ms) and its sibling fertile plants (K305F, ms/Ms) were obtained from the inbred line K305 by 60Co-γ irradiation. Genetic analysis from our previous investigation indicated that a single recessive genic gene of ms305 controlled the male sterility of K305ms [35]. When compared with the normal K305F anthers, we found that the anthers of ms305 failed in extruding from the spikelet, and no pollen grain was produced inside anthers, leaving an empty shell ( Figure 1).…”

“…No mutant with the same abortion characteristics as ms305 has been reported in maize to the best of our knowledge. Our previous genetic mapping showed that male sterile gene of ms305 was located between two simple sequence repeat markers on chromosome 2L in a region of 10.3 cM, bnlg469b, and bnlg1940 [35]. Among the DEGs that were identified in 'cutin, suberine, and wax biosynthesis' and 'lipid metabolism' pathway, a KAS II (GRMZM2G124335) gene was found to be located in this region ( Figure 4C, Table S3); interestingly, this gene was the hub gene of highest degree value in the PPI network analysis; thus, further map-based cloning of KAS II will be helpful.…”

“…The sibling population of K305 male sterility, including K305 male sterility plants (K305ms, ms/ms) and K305 fertile plants (K305F, ms/Ms), were both obtained from inbred line K305 that was exposed to 60 Co-γ irradiation [35]. A segregation sibling population of 230 plants, which was constructed by crossing homozygous male sterile plants and heterozygous male fertile plants, was planted in Shuangliu, Sichuan Province, China (30_34 • N, 103_56 • E) in 2014.…”

“…Genetic analysis indicated that a single recessive gene of ms305 controlled the fertility traits of K305ms. Moreover, genetic mapping showed that the responsible gene was located between two simple sequence repeat markers on chromosome 2L in a region of 10.3 cM [35,36]. In this study, maize male sterile ms305 (K305ms) and their sibling male-fertile (K305F) plants were investigated by cytological, transcriptomic, and lipidomic analysis.…”