The isolation and characterization of a waxy mutant of diploid wheat ( Triticum monococcum L.)

Abstract

A waxy mutant of diploid wheat ( Triticum monococcum L.) was isolated by screening M 3 seeds derived from 1% ethyl methanesulfonate (EMS) mutagenized materials with KI-I 2 staining of endosperm starch. This mutant was controlled by a single waxy gene that completely lacked amylose, the 59-kDa waxy protein and the granule-bound starch synthase I (GBSS I) activity in the endosperm. Moreover, the T. monococcum exhibited the gene dosage effects in terms of amylose content, the amount of waxy protein and the GBSS activity. The chain length distribution of amylopectin of the waxy mutant endosperm starch slightly differed from that of the wild type; the long chains of DP≧19 were more enriched in the waxy amylopectin than those in the wild type. The mutant can be an important material for studies on starch metabolism and breeding in Triticum species.