Identification of a novel male sterile wheat mutant dms conferring dwarf status and multi-pistils

Abstract

Plant height and fertility are two important traits of wheat （Triticum aesfivum L.）, whose mutants are ideal materials for studies on molecular mechanisms of stem and floral organ development. In this study, we identified a dwarf, multi-pistil and male sterile （dms hereafter） wheat mutant from Zhoumai 18. Simple sequence repeat （SSR） marker assay with 181 primer pairs showed that only one locus of GWM148-2B was divergent between Zhoumai 18 and dins. There were three typical phenotypes in the progeny of dms, tall （T; ca. 0.8 m）, semi-dwarf （M; ca. 0.6 m） and dwarf （D; under 0.3 m） plants. Morphological investigation indicated that the intemode length of M was shortened by about 20-50 mm each; the intemode number of D was 2 less than that ofT and Zhoumai 18, and its internode length was shorter also. The pollen vigor and hybridization test demonstrated that dms mutant was male sterility. Segregated phenotypes in progeny of M suggested that the multi-pistils and sterility were controlled by one recessive gene locus which was designated as dms temporarily, and the plant height was controlled by a semi-dominant gene locus Dms. Therefore, progeny individuals of the dms had three genotypes, DmsDms for tall plants, Dmsdms for semi-dwarf plants and dmsdms for dwarf plants. The mutant progenies were individually selected and propagated for more than 6 generations, thus a set of near isogenic lines of T, M and D for dms were developed. This study provides a set germplasms for studies on molecular mechanisms of wheat stem and spike development.