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

Institute of Cytology and Genetics, Novosibirsk, 630090, RUSSIA

After treatment of the line SG with 0.15% EMS the mutants SGE-0659 and SGE-0292 were isolated from M2 generation. The SGE-0659 mutant has white flowers, normal anthocyanin-colored violet stipula ring and violet dots on the seed testa caused by the gene Fs. The line SGE-0292 has flowers with a pale-pink vexillum and pink wings; the flower coloration is very similar to the coloration caused by the gene b. The stipula anthocyanin ring and color dots on the seed testa of this line have a pale-pink color while the testa background which is normally green in the line SG is ochrous, with more intensive coloration around the hilum and halaza-spot. Another mutant line - SGR-am, obtained independently from the line SG by treatment with 7 krad gamma-rays, has practically the same pattern of coloration, as the SGE-0292 line.

All these mutant lines were crossed with WL-1132, carrying a recessive allele of the gene am-1 (1), which cause the absence of anthocyan in flower structures but not affects the coloration of the other parts of the plant. All obtained mutants appeared to be allelic with Lamprecht's am-1 gene.

The table 1 shows the main differencies in the effects of distinct alleles of am-1 gene on the pea coloration pattern. It is worthly mention that am-1 gene is expressed not only in the flower structures, as it were earlier suggested, but may cause the coloration disturbances in all anthocyanin-colored pea organs. Moreover, the ochrous coloration of the seed testa in the lines SGE-0292 and SGR-am is more probably the result of producing not anthocyanins but pigments of flavonoid nature.

From M2 population of SG line treated with EMS a recessive mutant SGE-0634 which affects foliage was isolated. (Fig.1)

This mutant is characterized by the stipulae and leaflets slightly reduced in width ( two-thirds of the original line), a narrow leaflet base and well-noticebly curled stipulae. A cross with WL-1748, carrying a recessive allele of the gene red (reduced) (2), revealed that the newly obtained mutant is allelic to red of WL-1748 and dominate above it: all F1 plants were of SGE-0634 phenotype. We propose to call the new allele of the red gene of the SGE-0634 line as red ^s. Plants carrying red ^s allele, are 4-5 times more fertile than red plants and produce only slightly decreased amount of seeds, as compared with the ancestor SG line. Therefore, the new allele red ^s is more convenient for genetic experiments than Lamprecht's red allele, whose decreasing of the overall green mass cause the nearly sterile plants.

Some crosses with the obtained mutant lines were carried out, and the tight linkage of genes am-1 and red with the gene i established by Lamprecht (1,2) was proved (Table 2). Unfortunately, a small size of analyzed F2 population cannot provide significant data for proper mapping of this chromosome region, so the position of the red gene in relation to am-1 and i is still under the question.

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

References:

1. Lamprecht H., 1957. Agri Hort. Genet., v.15, p.155-168.

2. Lamprecht H., 1948. Agri Hort. Genet., v.6, p.10-48.