THE SELECTIVE VALUE OF MALE GAMETOPHYTES IN FERTILIZATION OF TOMATO REMOTE HYBRIDS IN DIFFERENT POLLEN REGIMES

Experimental proof of the selective advantage of fertilization by more self-incompatible (less self-compatible) pollen is presented. Four ca tegories of tomato hybrids were used: (1) intercultivar hybrids within the most self-compatible species from the genus Lycopersicon-L. escul entum (cultivated tomato); (2) L. esculentum hybrids with some wild se lf-compatible species that differ from the cultivated tomato by their higher ability for open pollination; (3) L. esculentum hybrids with th e self-fertile (i.e., intermediate between typical self-compatibility and self-incompatibility) L. hirsutum var. glabratum variety; and (4) L. esculentum hybrids with self-sterile (self-incompatible) representa tives of the L. hirsutum pecies. Deviations from the normal Mendelian monohybrid segregation with a deficit of recessive class (stambineus f orm of bush and potato-like leaves) was found in the F-2 generation, w hich was obtained from either the usual self-pollination or from artif icial pollination of F-1 plants. Deficit of recessives (stambineus pla nts) was found in the first backcross generation, when F-1 hybrids wer e used as a male form, and L. esculentum as female. Experimental mater ial, analyzed in connection with the S-genotype (factor of incompatibi lity) of male gametophytes and pistil, shows that the deviation degree of segregation directly depends on quantity of pollen during pollinat ion.