Aspectos morfológicos de folhas na diferenciação de variedades de carambola

Em certas espécies vegetais, a distinção entre variedades pode ser realizada com base em aspectos morfológicos das folhas, o que permite a diferenciação mesmo quando não apresentam flores e/ou frutos. O presente trabalho foi realizado objetivando a distinção entre variedades de caramboleira (Averrhoa carambola L.) através de aspectos foliares. Foram avaliadas quatro variedades de caramboleira: Arkin, B-10, Golden Star e Hart, com quatro repetições de 10 folhas cada. Pelos resultados obtidos no presente trabalho, conclui-se que há diferenças morfológicas foliares entre as variedades de caramboleira, permitindo a sua distinção, especialmente em condições de viveiro.

Influência do ácido indolbutírico no enraizamento de estacas apicais e basais de caramboleira (Averrhoa carambola L.) sob condições de nebulização intermitente

A produção de mudas de caramboleira é um dos fatores limitantes à expansão comercial da cultura, devido ao tempo que estas levam para serem formadas e iniciarem a produção. Uma boa alternativa pode estar na otimização dos métodos de propagação vegetativa, através de estudos relativos aos processos e fatores envolvidos no enraizamento de estacas. Este trabalho foi desenvolvido com o objetivo de estudar o enraizamento de estacas apicais e basais de caramboleira, tratadas com ácido indolbutírico (IBA), em condições de nebulização intermitente. Estacas apicais e basais de caramboleira foram coletadas de ramos de plantas-matrizes da cultivar B-10 e submetidas à aplicação de cinco concentrações de IBA (0; 1.000; 3.000; 5.000 e 7000 mg.L-1), em imersão por 10 segundos, para avaliar a capacidade de sobrevivência, enraizamento e número médio de raízes/estaca. Posteriormente, as estacas foram colocadas em caixas de madeira contendo vermiculita média como substrato e mantidas em casa de vegetação, sob nebulização intermitente, durante 70 dias. O delineamento experimental utilizado foi em esquema fatorial 2 x 5, com 4 repetições e 10 estacas/parcela. As estacas apicais obtiveram melhores resultados para porcentagem de sobrevivência (49,26%), enraizamento (34,84%) e número médio de raízes (20,51), mostrando-se superiores às basais. O uso de IBA não influenciou em nenhuma das variáveis analisadas.

Soil-liming effects on the development and nutritional status of the carambola tree and its fruit-yielding capacity

Soil acidity is one of the most important factors limiting agricultural production in the tropics. For this reason, the objective of this research work was to evaluate the effects of soil liming on the performance of carambola (Averrhoa carambola) trees. The experiment took place at the Citrus Experimental Station in Bebedouro, state of São Paulo, Brazil. The soil was a Typic Haplustox (V = 26% at the 0- to 20-cm layer) between August 1999 and July 2003. The following doses of limestone were employed: 0, 1.85, 3.71, 5.56, and 7.41 t ha(-1). During 40 months after the experiment was set up, soil chemical attributes were periodically examined. For a period of 2 years, the trees had their leaves analyzed for micro-and macronutrients; their trunk diameter, height, and crown volume measured; and the production of fruits determined. Liming improved in evaluated chemical attributes of the soil: pH, calcium (Ca), magnesium (Mg), BS, V, and hydrogen and aluminium (H + At) from the upper 60 cm of soil when the samples were taken from both the line and between the lines of plants. In the leaves, the levels of Ca and Mg also increased. The highest fruit yields were observed when soil base saturations reached 45% on the lines and 50% between the lines, as well as when foliar levels of 8.0 g of Ca and 4.7 a of Mg per kilogram of leaves were attained.

Liming and postharvest quality of carambola fruits

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Use of modified atmosphere to extend shelf life of fresh-cut carambola (Averrhoa carambola L. cv. Fwang Tung)

Fresh-cut fruit products, including carambola (Averrhoa carambola L.), have limited marketability due to cut surface browning attributed to phenolic compound oxidation by enzymes, such as polyphenol oxidase (PPO). The objective of this study was to evaluate postharvest changes in carambola slices in three different packages. Carambola fruit (cv. Fwang Tung) were picked from the Estacao Experimental de Citricultura de Bebedouro orchard at the mature-green stage. The fruit were washed, dipped in NaOCl solution (200 mg L-1 for 5 min), stored overnight at 10 degrees C, then manually sliced into pieces of approximately 1 cm. The slices were rinsed with NaOCl solution at 20 mg L-1, drained for 3 min, and packaged in polyethylene terephthalate (PET) trays (Neoform (R) N94); polystyrene trays covered with PVC 0.017 turn (Vitafilm (R), Goodyear); and vacuum seated polyolefin bags (PLO, Cryovac (R) PD900). The packages were stored at 6.8 degrees C and 90% RH for 12 d, with samples taken every 4 d. PET trays and PVC film did not significantly modify the internal atmosphere and the high water permeability of PVC led to more rapid slice desiccation. PPO activity was lower when the slices were packaged in PLO vacuum sealed bags, which reduced degreening and led to better appearance maintenance for up to 12 d. (R) 2006 Elsevier B.V. All rights reserved.

Response of minimally processed carambola to chemical treatments and low-oxygen atmospheres

Fresh-cut carambola (Averrhoa carambola L.) has limited marketability due to cut-surface browning. The effect of chemical treatments (ascorbic acid, citric acid and Ca-EDTA), controlled atmosphere (0.4-20.3% O-2) and the association of these processes was investigated. Post-cutting dip and low-oxygen atmospheres did not prevent discoloration or improve sensory and physicochemical parameters. However, ascorbic acid (0.5% and 1%) dips reduced polyphenol oxidase (PPO) activity during storage at 4.5 degrees C, with 1% ascorbic acid inducing the lowest activity. Although cut-surface browning of 'Maha' slices was not relevant, carambola slices treated with 1% ascorbic acid in association with 0.4% oxygen did not present significant browning or loss of visual quality for up to 12 days, 3 days longer than low oxygen alone (0.4% O-2), thus, their quality can be significantly improved by combining both treatments. (c) 2007 Elsevier B.V. All rights reserved.

Comparação entre cultivares de carambola para produção de produtos minimamente processados

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

CARACTERIZAÇÃO PÓS-COLHEITA DE SEIS CULTIVARES DE CARAMBOLA (Averrhoa carambola L.)

Avaliaram-se as qualidades física e química dos frutos de seis cultivares de carambola (Averrhoa carambola L.), propagadas pela Estação Experimental de Citricultura de Bebedouro, São Paulo, objetivando a obtenção de informações sobre a qualidade dos frutos produzidos nesta região. Foram utilizados frutos das cultivares Tean-ma, Fwang Tung, Arkin, Malásia, Golden Star e Nota-10. Os frutos foram analisados quanto à massa fresca, comprimento, largura, volume, porcentagem de suco, polpa e semente, número de sementes, coloração (L, Cromaticidade e ângulo Hue). Na polpa, determinou-se o pH, assim como o teor de umidade, sólidos solúveis totais (SST), acidez total titulável (ATT), vitamina C, açúcares solúveis totais e redutores, cinzas, proteína, pectina total e solúvel, e minerais (Ca, P, K, Mg, S, Cu, Fe, Mn e Zn). Os resultados foram avaliados estatisticamente através de um delineamento inteiramente casualizado e revelaram que os melhores frutos são os originários das cultivares Arkin, Tean-ma e Nota-10, pois são os maiores, os mais pesados e apresentam os maiores teores de sólidos solúveis totais (SST) e açúcares solúveis (AST), assim como boa relação SST/ATT. Os frutos da 'Arkin' mostraram coloração mais amarela, enquanto os da 'Golden Star' foram considerados de coloração mais clara, ou com maior translucidez. A textura foi menor nos frutos da 'Arkin', e se relacionou com a maior solubilização de suas pectinas

Armazenagem em atmosfera modificada passiva de carambola azeda (Averrhoa carambola L.) cv. 'Golden Star'

Este trabalho avaliou o efeito das embalagens de polietileno de baixa densidade (PEBD), em diferentes espessuras, no prolongamento da vida útil pós-colheita de carambolas cv. 'Golden Star'. Os frutos foram colhidos fisiologicamente maturos, sendo selecionados pela ausência de defeitos e acondicionados nas embalagens de PEBD, constituindo os seguintes tratamentos: T1 - controle (sem embalagem); T2 - PEBD de 6 mim; T3 - PEBD de 10 mim; T4 - PEBD de 15 mim. Os frutos foram armazenados a 12 +/- 0,5 ºC e 95 +/- 5% de UR, por 45 dias, e mais 5 dias a 22 +/- 3ºC e 72 +/- 5% de UR. Vinte e quatro horas após a colheita e a cada nove dias, amostras eram retiradas do armazenamento refrigerado (AR), mantidas por 12 horas em condições ambiente (22 +/- 3ºC e 72 +/- 5% UR) e analisadas quanto à firmeza de polpa (FP), à perda de massa fresca, à coloração da epiderme, aos sólidos solúveis totais (SST), à acidez total titulável (ATT) e à ocorrência de distúrbios fisiológicos. Realizou-se também uma análise sensorial ao final do experimento. A maior firmeza de polpa e acidez total titulável, o melhor padrão de coloração, o menor conteúdo de sólidos solúveis totais, a ausência de manchas e podridões, e a melhor aceitabilidade pelos julgadores foram obtidos com os frutos acondicionados em embalagens de 10 mim.

Use of carambola (Averrhoa carambola L. 'Fwang Tung') fruit at two stages of maturity for fresh-cut products

Carambola fruit ('Fwang Tung') were picked at two stages of maturity: mature-green (50% yellow) and mature (100% yellow). Fruit were washed with water, dipped in NaOCl solution (200 mg.L-1 for 5 minutes), and stored over night at 10°C. Fruit were sliced manually in to pieces of approximately 1 cm thickness. Slices were rinsed with NaOCl solution at 20 mg.L-1, drained for 3 minutes, and packaged in polyethylene tereftalate (PET) trays provided with a fit cover (Neoform® N94). Packages were stored at 6.5°C and 85% RH for 9 days, and samples taken every 3 days for physical, chemical and biochemical analysis, respiration, and internal atmosphere composition. Immediately after cutting, slices at both stages of maturity showed a wounding response with a 5-fold increase in respiration rate. Polygalacturonase (PG) and polyphenol oxidase (PPO) activity did not differ between stages of maturity. Despite the less mature stage being less preferred at the sensory evaluation owing to its greenish peel, the best stage of maturity for carambola fresh-cut production was mature-green, due to a higher resistance to cutting, and presenting a better colour and appearance maintenance for up to 9 days.

Use of modified atmosphere to extend shelf life of fresh-cut carambola (Averrhoa carambola L. cv. Fwang Tung)

Fresh-cut fruit products, including carambola (Averrhoa carambola L.) have limited marketability due to cut surface browning attributed to oxidation of phenolic compounds by enzymes such as polyphenol oxidase (PPO). The objective of this study was to evaluate postharvest changes of carambola slices in three different packagings. Carambola fruit (cv. Fwang Tung) were picked from the orchard of Estação Experimental de Citricultura de Bebedouro at mature-green stage. Fruit were washed, dipped in NaOCl solution (200 mg.L -1 for 5 minutes), and stored overnight at 10°C. Fruit were manually sliced into pieces of approximately 1 cm. Slices were rinsed with NaOCl solution at 20 mg.L-1, drained for 3 minutes, and packaged in polyethylene terephthalate (PET) trays (Neoform N94); polystyrene trays covered with PVC 0.017 mm (Vitafilm - Goodyear); and vacuum sealed polyolefin bags (PLO, Cryovac PD900). The packages were stored at 6.8°C and 90%RH for 12 days and samples taken every 4 days. PET trays and PVC film did not significantly modify internal atmosphere and the high water permeability of PVC led to more rapid slice desiccation. PPO activity was lower when slices were packaged in PLO vacuum sealed bags, which reduced discolouration and led to better appearance maintenance for up to 12 days.

Multivariate analysis of fresh-cut carambola slices stored under different temperatures

Quality of fresh-cut carambola (Averrhoa carambola L) is related to many chemical and biochemical variables especially those involved with softening and browning, both influenced by storage temperature. To study these effects, a multivariate analysis was used to evaluate slices packaged in vacuum-sealed polyolefin bags, and stored at 2.5 degrees C, 5 degrees C and 10 degrees C, for up to 16 d. The quality of slices at each temperature was correlated with the duration of storage, O(2) and CO(2) concentration in the package, physical chemical constituents, and activity of enzymes involved in softening (PG) and browning (PPO) metabolism. Three quality groups were identified by hierarchical cluster analysis, and the classification of the components within each of these groups was obtained from a principal component analysis (PCA). The characterization of samples by PCA clearly distinguished acceptable and non-acceptable slices. According to PCA, acceptable slices presented higher ascorbic acid content, greater hue angles ((o)h) and final lightness (L-5) in the first principal component (PC1). On the other hand, non-acceptable slices presented higher total pectin content. PPO activity in the PC1. Non-acceptable slices also presented higher soluble pectin content, increased pectin solubilisation and higher CO(2) concentration in the second principal component (PC2) whereas acceptable slices showed lower total sugar content. The hierarchical cluster and PCA analyses were useful for discriminating the quality of slices stored at different temperatures. (C) 2011 Elsevier B.V. All rights reserved.

Crescimento, teor e acúmulo de nutrientes em hipobiotos de caramboleiras, cultivados em diferentes soluções nutritiva

O Brasil é um dos maiores produtores de carambola do mundo, entretanto, há poucas informações científicas, especialmente estudos de nutrição mineral em caramboleiras. O presente trabalho foi desenvolvido com o objetivo de estudar o efeito de soluções nutritivas no desenvolvimento e no estado nutricional de hipobioto (porta-enxertos) de caramboleira. O delineamento experimental empregado foi inteiramente casualizado, com quatro soluções nutritivas e cinco repetições. Como solução padrão foi utilizada a de Hoagland & Arnon, comparada com outras três soluções. O experimento foi conduzido em estufa de vidro, em recipientes plásticos de oito litros. Cento e cinqüenta dias após o transplantio, foram determinados a massa da matéria seca, teores e acúmulo de nutrientes nos diversos órgãos da planta. As soluções nutritivas de Furlani, de Castellane & Araújo e de Sarruge foram semelhantes na produção de massa da matéria seca da planta inteira de hipobiotos de caramboleira. O uso da solução nutritiva de Hoagland & Arnon resultou em menor acúmulo da massa da matéria seca na planta inteira e de nutrientes, exceto de N, Ca e Fe.

Influence of different tropical fruits on biological and behavioral aspects of the Mediterranean fruit fly Ceratitis capitata (Wiedemann) (Diptera, Tephritidae)

Influence of different tropical fruits on biological and behavioral aspects of the Mediterranean fruit fly Ceratitis capitata (Wiedemann) (Diptera, Tephritidae). Studies on Ceratitis capitata, a world fruit pest, can aid the implementation of control programs by determining the plants with higher vulnerability to attacks and plants able to sustain their population in areas of fly distribution. The objective of the present study was to evaluate the influence of eight tropical fruits on the following biological and behavioral parameters of C. capitata: emergence percentage, life cycle duration, adult size, egg production, longevity, fecundity, egg viability, and oviposition acceptance. The fruits tested were: acerola (Malpighia glabra L.), cashew (Anacardium occidentale L.), star fruit (Averrhoa carambola L.), guava (Psidium guajava L.), soursop (Annona muricata L.), yellow mombin (Spondias mombin L.), Malay apple (Syzygium malaccense L.), and umbu (Spondias tuberosa L.). The biological parameters were obtained by rearing the recently hatched larvae on each of the fruit kinds. Acceptance of fruits for oviposition experiment was assessed using no-choice tests, as couples were exposed to two pieces of the same fruit. The best performances were obtained with guava, soursop, and star fruit. Larvae reared on cashew and acerola fruits had regular performances. No adults emerged from yellow mombin, Malay apple, or umbu. Fruit species did not affect adult longevity, female fecundity, or egg viability. Guava, soursop, and acerola were preferred for oviposition, followed by star fruit, Malay apple, cashew, and yellow mombin. Oviposition did not occur on umbu. In general, fruits with better larval development were also more accepted for oviposition.

Fruit flies (Diptera, Tephritidae) and their parasitoids on cultivated and wild hosts in the Cerrado-Pantanal ecotone in Mato Grosso do Sul, Brazil

Fruit flies (Diptera, Tephritidae) and their parasitoids on cultivated and wild hosts in the Cerrado-Pantanal ecotone in Mato Grosso do Sul, Brazil. Information on frugivorous flies in cultivated or wild host plants and their parasitoids in the Cerrado-Pantanal ecotone in Aquidauana, Mato Grosso do Sul is presented and discussed. Fruit fly samples were collected weekly in specific fruit trees, and McPhail® traps were installed in the same trees for a period of two years. The fruit flies infested ripe and unripe fruits of Averrhoa carambola L., Schoepfia sp., Psidium guajava L. and Pouteria torta (Mart.) Radlk and mature fruits of Anacardium occidentale L. and Inga laurina (Sw.) Willd. Nineteen fruit fly species were obtained with the combination of sampling methods (collecting fruits and trapping), nine of them obtained with both methods, five found only in fruits and five only in traps. This is the first record of Anastrepha striata Schiner in a species of Sapotaceae, as well as for A. castanea Norrbom and A. daciformes Bezzi in Schoepfia sp. (Olacaceae), and for A. distincta Greene in fruits of P. guajava in the state of Mato Grosso do Sul. Fruit collections simultaneously associated with capture of fruit flies by McPhail traps in the same host plants are essential to understand the diversity of fruit flies and their relationship with hosts and parasitoids. Species of Braconidae and Pteromalidae were recovered, where Doryctobracon areolatus (Szépligeti) was the most abundant parasitoid in larvae of tephritids infesting both cultivated and wild host fruits.