A mutant having six-rowed gene allelic to v locus.
Tokuhiko Makino, Masahiko Furusho and Tadahiko Fukuoka
National Agriculture Research Center,Tsukuba,Ibaraki 305,JAPAN

Air-dried seeds of two-rowed cultivar, New Golden, were irradiated by gamma-ray of 30 kR with 1 kR/h. About 1200 M/1/ seeds were planted in the density of 110 plants/mē. The bulked M/2/ seeds obtained were planted individually with the distance of 10 cm. Among ca. 5000 M/2/ plants grown, three plants had six-rowed spikes. M/3/ lines (named as M-32, 33 and 34) of them revealed uniform morphology and segregate none of other visible characters. Thus, these lines were crossed to the original cultivar and sterile line having six-rowed spike, originally developed by Falk and Kasha (1982). Moreover, intercrossing were carried out among three lines.

F/1/ plants between M-32 or M-33 and M-34, between New Golden and each of three mutant lines, and between six-rowed male sterile line and M-32 or M-33 showed two-rowed spikes. On the other hand, F/1/ plants between M-32 and M-33, and between M-34 and six-rowed male sterile line showed six-rowed spikes. Therefore, each of two mutants, M-32 and M-33, has the same mutant gene being non-allelic to v locus and the mutant gene of M-34 is allelic to v locus. In fact, among ca. 12000 plants of the F/2/ between six-rowed male sterile line and M-34 only six plants showed two-rowed spikes. We proposed that a mutant gene of M-34 is symbolized as v1b. Seeds of this mutant are available for distribution.

References:

Falk, D. E. and K. J. Kasha 1982. Registration of a shrunken endosperm, male-sterile germplasm to facilitate hybridization in barley. Crop Science 22:450.