Articles
EFFECTS OF INDOLE-3-ACETIC ACID AND GIBBERELLINS ON FRUIT DEVELOPMENT AND MATURATION OF SWEET CHERRIES
IAA was analyzed by the indolo-a-pyrone fluorescence method using HPLC. GAs were estimated by the dwarf rice seedling bioassay.
The IAA level in the seed rose at the early stage of fruit development (24 d after full bloom (DAFB)) and before fruit maturation (33 DAFB). In contrast, its level in the pulp rose at 22 DAFB and at the beginning of fruit maturation period (43 DAFB). Generally, an increase in the IAA levels in the seed preceded an increase in the pulp.
The variations in the IAA levels in the seed and the pulp corresponded to changes in fruit diameter, suggesting that IAA might be related to the fruit development.
The level of GAs in the seed increased gradually before fruit maturation (38 DAFB) and then decreased dramatically towards harvest.
However, the level in the pulp was initially lower and increased at fruit maturation stage (47 DAFB). As with the IAA, the GAs level in the seed increased prior to a corresponding increase in the pulp.
A correlation of the GAs variation with the changes of fruit diameter was not apparent.
The application of 2,4-DP or GA3 to the fruit at 15 and 23 DAFB delayed fruit maturation (softening and anthocyanin accumulation). The effects of IAA and GAs on fruit development and maturation of sweet cherries were discussed.