Gorel F.L., Rozov S.M., Berdnikov V.A.,

Institute of Cytology and Genetics, 630090, Novosibirsk, RUSSIA.

A mutant SGR-a with white flowers and complete absence of anthocyanin in all plant organs was induced in the SG line after 7 krad gamma rays treatment. SGR-a was crossed with line Sprint-1, contrast in allelic variants of the His(2-6) locus, the complex of histone H1 genes, known to be linked with the gene a (1). Although the SGR-a mutant phenotype is identical to the phenotype caused by gene a (anthocyanin inhibition), we failed to find any linkage of this mutant trait with the histone H1 locus His(2-6). F1 plants from the cross SGR-a x WL-102 ( a ) had red flowes. These experiments indicated that our mutation involves a locus another than a.

Earlier a new locus a-2 controlling the anthocianin production was described by Marx with collegues (2). The F1 plants after the cross of the SGR-a with Marx's a-2 line had white flowers, that showed our newly obtained anthocyanin mutant appeared to be allelic to Marx's a-2 locus.

After treatment of the line SG with 0.15% EMS another mutant SGE-0845 completely lacking of anthocyanin was obtained. SGE-0845 also was proved to be allelic to Marx's a2.

To localize the a2 gene we crossed the line SGR-a (A, a-2, St) with the tester line WL-1393 (A, A-2, st). The analysis of F2 progeny (Table 1) shows that the a2 locus is linked to the gene st belonging to the linkage group III.

We crossed one plant with phenotype a-2, st from the above mentioned F2 population with the line SGE-0656 (A-2, St, uni).(This mutant line was obtained after EMS-treatment of SG, has phenotype the same as uni tac and was proved to be allelic to uni (tac)) Besides, the line SGE-0845 (a-2, Uni) was crossed with line SGE-0656 (A-2, uni). The combined results obtained from these two crosses are given in the Table2.

Therefore, the data obtained in this work indicate that gene a-2 is located in pea linkage group 3.

Authors are grateful to Dr. N. Weeden for the providing seeds of his a-2 line, and also for the useful comments and discussion of the manuscript.

This work was partially supported by the Russian State Program for Fundamental Research.

References:

1. Smirnova O.G., Rozov S.M., Berdnikov V.A. 1989. PNL 21:63-65.

2. Marx G.A., N.F. Weeden and F.J.Muehlbauer 1989. PNL 21:35-36.