II.15 A new smooth-awn gene on chromosome 6.
Takeo Konishi. The Ohara Institute for Agricultural Biology, Okayama University, Kurashiki, Japan.
A smooth-awned mutant was induced from a naked "uzu" cultivar., Akashinriki, by EMS treatment. Since the F1 hybrid between this mutant and the ordinary smooth-awned form had rough-awn, the mutant gene was known to be different from the r gene on chromosome 7. The mutant character was shown to be controlled by a single recessive gene, tentatively named r,,e. As shown in Table 1, the new smooth-awn gene was linked with the gene for orange lemma (o) on chromosome 6, and the recombination value estimated from F2 data was 9.49%, and those from two kinds of tests with singly dominant F3 progenies, Ab and aB, was 13.13% and 10.59%. The weighted value of p was 11.57%. Interrelationships of the gene for the smooth-awn with several chromosome markers were investigated in three crosses. Experimental data reveal that r,,e was inherited independently of n (chromosome 1), V (2), uz (3), K (4), B (5), and s (7), respectively. As only a few marker genes have been located on chromosome 6, this viable gene may be of value for linkage tests.
(Editor's Note: The symbol, r2, used by the author had been previously assigned. The provisionary symbol, r,,e, was substituted r2 in the manuscript.)
Table 1. Linkage between r,,e (smooth awn) and o (orange lemma).
