susceptible . This fact indicates that the gene of resistance in line LCHG 177 is not allelic to gene Pto in ONT 7710 (Table 2) . Table 2 . Test of allelism in line ONT 7710 and line LCHG 177 Segregation Crosses Progenies R S c 2 P> ONT 7710 x LCHG 177 F1 32 0 ONT 7710 x LCHG 177 F2 234 86 0 . 075 0 . 50>P>0 . 80 R - resistant, S – Susceptible We believe that the presence of a novel gene could be responsible for the resistance to race 1 of Pst . Further studies are required to clarify the nature and the expression of this novel gene in line LCHG 177 . Acknowledgements This work was supported by the National Science Fund (contract SS 806/98) Literature cited: Bogatsevska, N . 1988 . Plant Science, 27, 5:91 - 96 Bogatsevska, Sotirova, V . and Stamova, L . 1989 . Tomato Genetic Cooperative Report, 39:7 Buonario, R . , Stravato, V . and Cappeli, S . 1996 . J . Phytopathology, 144:437 - 440 . Gitaitis, R . , McCarter, S . and Jones, J . 1992 . Plant Dis . , 76:651 - 656 Lawton, M . B . and McNeil, B . H . 1986 . Can . J . of Plant Pathology, 8:85 - 88 Pitblado, R . E . and Kerr, E . A . 1980 . Acta Horticulture, 100:379 - 382 Pitblado, R . E . and MacNeil, B . H . 1984 . Can . J . of Plant Pathology, 6:48 - 53