Although many mutants in barley reduce plant height, relatively few have been used in cultivar development. Mickelson and Rasmusson (1994) reported that cultivars in the intermediate height class often have a mutant at the sdw (semidwarf) locus. This reconfirms the report by Haahr and Wettstein (1976) regarding alleles for plant height in cultivars from Europe and North America selected from crosses to Diamant (Valticky) and Jotun, respectively. Many short stature cultivars were found to have sdw and an additional recessive gene for plant height reduction (Mickelson and Rasmusson, 1994). Gymer (1993) demonstrated that the sdw locus is not in chromosome 7 and presented evidence for linkage to the B (black lemma and pericarp) locus in chromosome 5L.
Thomas et al. (1991) studied changes in agronomic and malt quality traits associated with two semidwarf genes. The Golden Promise gene (GPert, an allele at the ari-e locus in chromosome 7) was associated with low 1000-grain weight, low yield, low hot water extract, and high milling energy. The other semidwarf gene (denso or sdw) was associated with late heading, low 1000-grain weight, and high ß-glucans content. Delayed maturity and other pleiotropic effects of the sdw gene in North American germplasm were reported by Foster and Thompson (1987).
Nedel et al. (1993) reported that semidwarf mutants induced in malting barley cultivars do not differ from their parental cultivars in utilization of nitrogen fertilizer. However, the four semidwarf lines yielded less than their standard height parents.
References
Foster, A.E., and A.P. Thompson. 1987. Effects of a semidwarf gene from Jotun on agronomic and quality traits in barley. p. 979-982. In S. Yasuda and T. Konishi (eds.) Barley Genetics V. Proc. Fifth Intl. Barley Genet. Symp., Okayama 1986. Sanyo Press Co., Okaymna.
Gymer, P.T. 1993. An attempt to locate the sdw gene for prostrate growth habit or the perils and pitfalls of classical genetics. BGN 22:19-22.
Haahr, V., and D. von Wettstein. 1976. Studies of an induced, high-yielding dwarf mutant of spring barley. p. 215-218. In H. Gaul (ed.) Barley Genetics III. Proc. Third Intl.Barley Genet. Symp., Garching, 1975. Verlag Karl Thiemig, München.
Mickelson, H.R., and D.C. Rasmusson. 1994. Genes for short stature in barley. Crop Sci.34:1180-1183.
Nedel, J.L., S.E. Ullrich, J.A. Clancy, and W.L. Pan. 1993. Barley semidwarf and standard isotype yield and malting quality response to nitrogen. Crop Sci. 33:258-263.
Thomas, W.T.B., W. Powell, and J.S. Swanston. 1991. The effects of major genes on quantitatively varying characters in barley. 4. The GPert and denso loci and quality characters. Heredity 66:381-389.