Reguladores de crescimento na frutificação efetiva e qualidade de frutos partenocárpicos de atemoia 'Gefner'

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...

Gibberellic acid induces parthenocarpy and increases fruit size in the ‘Gefner’ custard apple (Annona cherimola x Annona squamosa)

“…Similar behavior was observed in Homestead, South Florida. 'Gefner' custard apple flowers treated with 1,000 ppm GA 3 at anthesis and at the 1 st , 3 rd and 5 th WAA without hand pollination (HP) presented an average of 80% fruit set by fruit harvest at the 19 th WAA (Pereira et al, 2014). Another study also showed that the number of applications of plant-growth regulators affects the fruit set.…”

“…Similar results were observed by Saavedra (1979), Yonemoto et al (2004) and Pino (2008), who also found high rates of parthenocarpic fruits in cherimoya. According to Pereira et al (2014), the use of 1,000 ppm GA 3 resulted in 80 % seedless fruits in the 'Gefner' custard apple, and when applied to pollinated fruits, this same dose resulted in the lowest seed number/100 g of fruit and pulp ratio. No significant differences were observed among the treatments for the percentage of fruit pulp, ranging from 64.2 to 73.9 % (Fig 4).…”

“…Similarly, gibberellins play a key role in the fruit setting and growth process. Studies of species belonging to the Annonaceae family have reported an effect of gibberellins on fruit setting, increased fruit size and the production of seedless fruits (Saavedra, 1979, Yonemoto et al, 2004Pereira et al, 2014). Saavedra (1979) published one of the first reports on the use of gibberellic acid (GA 3 ) in Annonaceae.…”

“…Yonemoto et al (2004), working with 'Big Sister' and 'Suiho' cherimoya cultivars, succeeded in growing seedless fruits with the same quality as the pollinated fruits. Recent studies also showed that applying 1,000 ppm GA 3 without hand pollination enabled the production of parthenocarpic custard apple fruits (Pereira et al, 2014). Despite these significant advances, seedless custard apple fruits still do not have the desired standard commercial grade, indicating the need for more detailed studies in order to achieve this goal.…”

QUALITY OF ACEROLA (Malpighia emarginata) TREATED WITH GIBBERELIC ACID AND STORED UNDER REFRIGERATION

“…The application of plant hormones on fruit production has shown positive results in relation to the increase of the physical variables on pitayia (NOR et al, 2014), inhibition of maturation and extension of the postharvest of bananas (HUANG;JING, 2012), and improving of physiochemical characteristics of apples (YILDIZ et al, 2012). Among the plant regulators used in postharvest of fruits, gibberellic acid (GA 3 ) exerts a great influence on the quality and extension of postharvest of grapes (MARZOUK; KASSEM, 2011) and fruiting of atemoieira (PEREIRA et al, 2014).…”