EFFECT OF METHYL JASMONATE ON IN-VITRO STRAWBERRY RIPENING

Strawberry fruits (Fragaria x ananassa Duch.), cultivar Camarosa, were harvested at green inmature stages and grown in vitro in sucrose-cont aining solutions. The effect of exogenously added methyl jasmonate (JA Me, 50 mu M) on in vitro development and ripening of strawberry was ev aluated through different parameters. A significant increase in respir atory activity and ethylene production was determined in white and pin k strawberries treated with JAMe, while different responses were elici ted from ripe and overripe fruits. A higher growth rate was found in J AMe-treated fruits, with a 55% weight gain against 33% for control fru its. A significant effect of JAMe treatment on strawberry color evolut ion was also observed by a stimulation of anthocyanin biosynthesis aft er 2 days of treatment and an accelerated degradation of chlorophyll a , chlorophyll b, and, to a lesser extent, beta-carotene and lutein.