II.36. New linkage data obtained during 1972-73 season.
R. Takahashi, J. Hayashi and I. Moriya. The Ohara Institute for Agricultural Biology, Okayama University, Kurashiki (710), Japan.
1. Locating mt,,e for mottle leaves in Victorie on chromosome 2.
It was reported in BGN 2 (p.74) that a gene mt,,e in a cv. Victorie is on chromosome 2. Its location was determined by F2 test of a cross between the mutant and a linkage tester, L.T. 32 (li-v-e). The linkage data obtained and a map of four genes are as follows.
2. F3 data for the linkage of "Curly 2" in Chôshirô-hen.
In BGN 2 (p.128) are reported the results of an F2 test for interrelationships of cu2 in Chôshirô-hen with als and uz using a cross, Chôshirô-hen x Absent lower laterals (als-Cu2-Uz). In 1972-73 season, F3 families derived from the above cross were reared. In the following table are given the summarized results of the F2 and F3 segregations. The weighted average values of recombinations, calculated from the combined F2 and F3 data, are also shown in the same table.
3. A new white-stripe mutant, OUM 231, wst,,j on chromosome 3
The white stripe character of OUM 231, induced by EMS treatment by T. Konishi of this institute, is of a low-temperature type. When grown at low temperature condition, its leaf-sheaths and most of the leaf-blade becomes whitish or white-striped, and only the leaf-tip and central portion along the midrib of the blade remain green in general. However, the stripe character is not expressed at a temperature above 20°C.
Inheritance and linkage of the mutant character was investigated in F2 of a cross, OUM 231 x Russian 82, which has revealed that the character was inherited as simple recessive to normal and linked with uz and al on chromosome 3. The linkage data are given below:
4. A multiflorous mutant, OUM 173, mul,,c on chromosome 3.
A mutant OUM 173, induced by EMS treatment by T. Konishi, is characterized by a conspicuous multiflorus head. Inheritance of the mutant character was studied using a cross between OUM 173 and a tester stock, Col-orange. The results are shown below. It is apparent that the character is inherited as simple recessive to normal, and owing to high penetrance of the gene, the fit of the observed number to the expected ratio of 3:1 is very good.
The gene mul,,c seems to be on chromosome 3, but is independent of n(l), K(4), o(6) and s(7).
