Gibberellic acid and grapes: the efects of gibberellic acid on the internal browning of Thompson Seedless Table Grapes

In 1968 vines of Thompson Seedless Table Grapes were treated, with different concentrations of gibberellic acid, to determine if this chemical influenced, internal browning, a storage disorder. All treatments were sprayed, at bloom with 10 parts per million. Concentrations of 0, 20, lj.0 and. 100 parts per million gibberellic acid, were applied, at shatter. Fruit was harvested, on two dates and. placed, in cold, storage. A portion of the fruit was separated into maturity classifications and. placed, in. cold, storage. During the storage life of the fruit an average of 1.86$ of the berries inspected, were found, to contain internal browning. The disorder increased, with length of time fruit remained, in storage. The 0 parts per million gibberellic acid, applied, at bloom contained, the highest amount of internal browning with the I4.O part per million post bloom application containing the least amount of the disorder. The 20 to 22 Balling separation was found, to contain, the highest amount of the disorder with 1.92% of its fruit containing internal browning. The fruit of the 18 to 20 Balling separation contained. 0.98% internal browning and. fruit of the 16 to lo Balling separation contained. 0.28% internal browning. Berry weight measurements were not significantly different, between the 40 and 100 part per million gibberellic acid treatments, but a composite Balling sample for the 100 part per million treatment was approximately 1.2 degree Balling lower than the Balling of the UO part per million treatment.