Seedlessness and Fruit Quality Traits of Gibberellin Induced Parthenocarpic Fruit in Seven Tomato Genotypes (Solanum lycopersicum L.)

Parthenocarpic fruit development is regulated by a plant hormone, i.e. gibberellin. The response of seven lines of tomato to gibberellin was investigated to distinguish the degree of parthenocarpy and to compare the quality of seedless and seeded fruits. The flower from stage 12 (size 5 mm) until 4 days after anthesis was sprayed with GA3 0 mmol/L and 0.06 mmol/L. The treatments were arranged in Randomized Complete Block Design with three replications. GA3 0.06 mmol/L reduced pollen germination, whose pollen germination (28.98%) was lower than 0 mmol/L (46.06%). The total numbers of seeds and fertilized seeds of treated fruit were significantly reduced in comparison with the control. Gibberellin application also increased the number of degenerated seeds. Within the genotypes studied, four groups were distinguished, which showed a different degree of parthenocarpy in response to gibberellin application. Kaliurang 206 and A65 are categorized as seedless with a 93.65% and 89.58% reduction in the total number of seeds, respectively. Gamato 1 is categorized as low-seeded with an 83.83% reduction in the total number of seeds. Gamato 3, Gamato 5, and B78 are categorized as medium-seeded with a 69.83-80.85% reduction in the total number of seeds, whereas A175 is categorized as normal-seeded with a 36.94% reduction in the total number of seeds. Gibberellin significantly increased the sugar content by 14.04% and reduced the ascorbic acid content by 9.68% of parthenocarpic fruits compared with the untreated.