Gibberellic acid combined with hand pollination increases ‘Red’ and ‘Lessard Thai’ sugar apple fruit quality and produced parthenocarpic ‘Gefner’ atemoya fruits

Ácido giberélico associado com a polinização manual incrementa a qualidade dos frutos em anonáceas e produz frutos partenocárpicos em atemoieira ‘Gefner’

ABSTRACT:

The present research aimed to evaluate the effect of applying gibberellic acid (GA₃) with hand (HP) or natural pollination (NP) on fruit set and the fruit quality of ‘Red’ and ‘Lessard Thai’ sugar apple and ‘Gefner’ atemoya fruits.This study was performed in an experimental orchard located in Homestead, Florida, USA. The experimental design included randomized blocks, with eight treatments, four replicates and four plants per plot. Treatments included: (1) HP; (2) HP + 10 mg L^-1 GA₃; (3) HP + 100 mg L^-1 GA₃; (4) HP + 1,000 mg L^-1 GA₃; (5) NP; (6) NP + 10 mg L^-1 GA₃; (7) NP + 100 mg L^-1 GA₃ and (8) NP + 1,000 mg L^-1 GA₃. The HP plus 1,000 mg L^-1 GA₃ promoted fruit setting above 90% over the 14 weeks for all genotypes evaluated. Significant increments for length and total fruit weight were observed. ‘Red’ sugar apple and atemoya had a reduced number of seeds per fruit. The NP plus GA₃ (1,000 mg L^-1) was effective in producing high quality seedless ‘Gefner’ atemoya fruits. This investigationdemonstratedthat GA₃ plus hand pollination produced high quality sugar apple and atemoya seeded fruits and in association with natural pollination promoted seedless ‘Gefner’atemoya fruits.

Key words: Annona squamosa; A. cherimola x A. squamosa; fruit set; parthenocarpy; plant growth regulator; seedless fruits.