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

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.摘要：本研究旨在评估人工授粉（hand pollination, HP）与自然授粉（natural pollination, NP）配合赤霉素（gibberellic acid, GA3）施用，对‘红皮’番荔枝、‘莱萨德泰国’番荔枝以及‘盖夫纳’阿蒂莫耶番荔枝的坐果率与果实品质的影响。本试验于美国佛罗里达州霍姆斯特德的一处实验果园开展。试验采用随机区组设计，设置8个处理、4次重复，每小区种植4株植株。处理组分别为：(1) 人工授粉（HP）；(2) 人工授粉+10 mg·L⁻¹ GA3；(3) 人工授粉+100 mg·L⁻¹ GA3；(4) 人工授粉+1000 mg·L⁻¹ GA3；(5) 自然授粉（NP）；(6) 自然授粉+10 mg·L⁻¹ GA3；(7) 自然授粉+100 mg·L⁻¹ GA3；(8) 自然授粉+1000 mg·L⁻¹ GA3。试验结果显示，施加1000 mg·L⁻¹ GA3的人工授粉处理，在14周观测期内对所有供试基因型的坐果率均提升至90%以上。同时观测到果实长度与总果重均有显著提升。‘红皮’番荔枝与阿蒂莫耶番荔枝的单果种子数有所减少。施加1000 mg·L⁻¹ GA3的自然授粉处理，可有效培育出高品质无籽‘盖夫纳’阿蒂莫耶番荔枝果实。本研究证实，赤霉素配合人工授粉可获得高品质带籽番荔枝与阿蒂莫耶番荔枝果实，而赤霉素与自然授粉联用则可培育无籽‘盖夫纳’阿蒂莫耶番荔枝果实。