Sawant, A.C.
Five male sterile plants of commercial variety San Marzano, 13 plants of Lycopersicon hirsutum and few F1 hybrids between two botanical forms of L. hirsutum, were planted in the field. The L. hirsutum and the F1 hybrids were self-incompatible. Along with these plants was grown a plant of L. hirsutum f. glabratum which is self-compatible.
All these plants produced normal amount of fruits with full complement of (forty or more) seeds. This lead to the suspicion of cross-pollination. The 13 hirsutum plants and the F1 hybrids were selfed and their anthers and corolla were removed. Fifteen to 27 flowers were worked on each plant before the opening of the corolla. None of these set the fruits. Further, three hirsutum plants and the glabratum plant were defruited and then covered with insect-proof cheese cloth. None of these set fruits while being covered. But after removing the cheese cloth they started fruiting.
Bumble bee was found to be the pollinating vector which regularly visits the flowers in the morning. It is likely that part of the difficulty in establisblng homozyosity in tomatoes here, even after 11 generations of field open pollination, may be arising out of this cross-pollination.