No abstract

Resumo -O objetivo deste trabalho foi avaliar os efeitos de reguladores de crescimento vegetal sobre a frutificação efetiva e a qualidade de frutos partenocárpicos de atemoia 'Gefner'. O experimento foi realizado em pomar de atemoia 'Gefner', em Homestead, Flórida, EUA. Utilizou-se um delineamento experimental de blocos ao acaso, com quatro tratamentos, cinco repetições e seis flores por parcela. Os tratamentos foram compostos por: T1, ácido naftaleno acético a 450 mg L -1 e ácido giberélico a 1.000 mg L -1 ; T2, promalina a 100 mg L -1 e ácido giberélico a 1.000 mg L -1 ; T3, ácido giberélico a 1.000 mg L -1 ; e T4, polinização artificial (testemunha). Foram avaliados a frutificação efetiva, o crescimento e a qualidade dos frutos. A aplicação dos ácidos naftaleno acético e giberélico a flores de atemoia 'Gefner' proporcionou elevada frutificação efetiva, semelhante à da polinização artificial. A aplicação do ácido giberélico, associado ou não ao ácido naftaleno ou à promalina, resulta na produção de frutos de atemoia 'Gefner' mais tardios e menores do que os oriundos da polinização artificial, mas com boa proporção de polpa, excelente teor de sólidos solúveis e, principalmente, frutos sem sementes (partenocárpicos).Termos para indexação: Annona cherimola, Annona squamosa, auxina, frutos sem sementes, giberelina, pegamento de fruto. Growth regulators on fruit set and quality of parthenocarpic fruit in atemoya 'Gefner'Abstract -The objective of this work was to evaluate the effects of plant growth regulators on the effective fruit set and quality of atemoya 'Gefner' parthenocarpic fruit. The experiment was carried out in an orchard of atemoya 'Gefner' in Homestead, Florida, USA. A randomized complete block design was carried out with four treatments, five replicates, and six flowers per plot. Treatments were composed of: T1, 450 mg L -1 naphthaleneacetic acid and 1,000 mg L -1 gibberelic acid; T2, 100 mg L -1 promalin and 1,000 mg L -1 gibberelic acid; T3, 1,000 mg L -1 gibberelic acid; and T4, artificial pollination (control). Effective fruit set, and fruit growth and quality were evaluated. The application of naphthaleneacetic and gibberelic acids on flowers of atemoya 'Gefner' provided high fruit set, similar to that of artificial pollination. Gibberelic acid application, associated or not with naphthaleneacetic acid or promalin, results in later and smaller atemoya 'Gefner' fruit than those obtained by artificial pollination, but with good proportion of pulp, excellent soluble solids content and, mainly seedless fruit (parthenocarpic fruit).Index terms: Annona cherimola, Annona squamosa, auxin, seedless fruit, gibberellin, fruit set. IntroduçãoO desenvolvimento de cultivares sem sementes tem atraído a atenção de produtores, que destacam a facilidade para o consumo in natura ou processado e o valor agregado do produto final, como algumas vantagens advindas desta nova característica (Pandolfini, 2009;Lora et al., 2011 Frutos sem sementes podem ser decorrentes de mutações, como em tomateiro e pinheira, ou de pro...

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.