GrainGenes
A Database for Triticeae and Avena
Takahashi, pp. 65-66
II.39. Two new mutant genes on chromosome 4.
R. Takahashi, J. Hayashi and I. Mortya. The Ohara Institute for Agricultural Biology, Okayama University, Kurashiki, Japan.
1. A "node-less" mutant.
A node-less mutant, R 101, was first induced by X-ray irradiation in a cultivar of uzu, naked type, Akashinriki, and received from Dr. Ohta, Shizuoka Prefectural Agricultural Experiment Station. The mature plant of this mutant develops several culms, each having only a single elongated internode and hence named "node-less", though several nodes are found in a compressed manner at the base. It is only one half as tall as the original variety, and less fertile.
Two crosses of this mutant with tester stocks, Col-orange and Nigrinudum, were used for inheritance and linkage studies. The F2 segregations in these crosses have shown that the character is determined by a single recessive gene (nls), which is linked with K for hooded lemma appendage on chromosome 4. The recombination percentage was estimated to be 28.51 + 2.6200 (%). Independent inheritance of the following marker genes were also confirmed: n(l), v(2), uz(3), B(5), o(6) and s(7).
2. A chlorina mutant.
A chlorina mutant strain, T. 95, was received from Dr. R. W. Woodward, Utah Agricultural Experiment Station. This is viable, though somewhat weak, under outdoor conditions, and develops chlorina leaves from seedling to near maturity, irrespectively of whether it is grown under low or high temperature conditions.
The mutant character was found to be conditioned by a single recessive gene which was linked with K with 9.22 + 1.5117 (%) recombination. The gene was shown not to be allelic to f9, a similar mutant on the same chromosome.