International Rice Research Institute, P. 0. Box 933, Manila, Philippines
The Adh-1 gene for alcohol dehydrogenase was assigned to linkage group 11 by Ranjhan et al. (1988). In order to map this gene on the linkage group we crossed marker stock (RGS1132) having linked markers v-4 (virescent), la (lazy), and Adh- 12 with an isozyme tester stock (IRRI Acc. 6245) having Adh-13. As the data of Table 1 show, Adh-1 was found to be linked with both v-4 and la. Recombination values were calculated using maximum likelihood formula (Allard 1956) and found to be 21+/-3.35 between Adh-1 and v-4 and 29+/-0.15 between Adh-1 and la. The map distance between v-4 and la was calculated to be 10+/-2.37 cM. These data show that v-4 is located between la and Adh-1 (Fig. 1). The linkage intensities between v-4 and la and Adh-1 and v-4 are similar to those reported by Ishikawa and Morishima (1989) did not detect and linkage between la and Adh-1.
Table 1. Segregation of three genes, v-4, la and Adh-1 in the F2 population of RGS 1132 X Acc. 6245
================================================================ Adh-1 Recombination Marker =============================Total value 3/3 3/2 2/2 ================================================================ v-4 normal 47 84 17 148 mutant 1 14 18 33 21+/-3.35 total 48 98 35 181 ================================================================ la normal 45 80 20 145 mutant 3 18 15 36 29+/-0.15 total 48 98 35 181 ================================================================ normal virescent normal 138 7 145 lazyant 10 26 36 10+/-2.37 total 148 33 181 ================================================================
References
Allard, R. W. 1956. Formulas and tables to facilitate the calculation of recombination values in heredity. Hilgardia 24(10): 235-278.
Ishikawa, R., T. Kinoshita and H. Morishima, 1988. Linkag analysis of the Pgd-1 locus. RGN 5: 81-82.
Ishikawa, R. and H. Morishima, 1989. Linkage analysis for four isozyme loci. Adh-1, Acp-1, Pox-2 and Pgd-2. RGN 6: 109-112.
Ranjhan, S., J. C. Glaszmann and G. S. Khush, 1988, Chromosomal location of four isozyme loci by trisomic analysis in rice (Oryza sativa L.). Theor. Appl. Genet. 75: 541-545.