Initiation at the flowering stage of postharvest Botrytis stem-end rot in normal and non-ripening tomato fruits

Flowers of a normal tomato cultivar and of the two non-ripening mutants rin and nor, were sprayed with a Botrytis cinerea spore suspension. Stem-end infection developed in 84–100% of the harvested fruits of these sprayed flowers when held in high r.h. In both nor and rin fruits, rot development remained restricted to the stem-end area and fruit shoulders, whereas in the normal fruit decay spread rapidly from the stem-end over the entire fruit. Spraying the flowers with iprodione prior to spore inoculation resulted in decreased incidence of decay and suppressed hyphal growth and sporulation in all types of fruits. The results indicate that floral organs serve as a pathway for B. cinerea stem-end initiation in both the normal and the mutant fruit and suggest that this mode of penetration is not related to the marked resistance to infection attributed to the mutant fruits.