Adubação nitrogenada e substratos na produção de mudas de maracujazeiro doce

Com o objetivo de avaliar diferentes substratos e doses de nitrogênio na produção de mudas de maracujazeiro doce, conduziu-se um experimento no Setor de Fruticultura do Departamento de Agricultura da Universidade Federal de Lavras (UFLA). Foram estudadas cinco doses de nitrogênio 0; 400; 800; 1600 e 3200 mg de N/dm³ e duas composições de substratos: A (composto orgânico + areia + solo na proporção de 1:1:3 em volume) e B (Plantmax® + areia + solo na proporção de 1:1:3 em volume ). Foi utilizado o delineamento experimental em blocos casualizados em esquema fatorial 5 x 2, com quatro repetições e cinco plantas por parcela. Foi observado que doses elevadas de adubação de cobertura com N podem promover efeitos depressivos nas mudas. E que o melhor substrato foi o B, contendo: Plantmax® + areia + solo na proporção de 1:1:3 em volume.

Influence of two methods of CaCl2 application and concentrations used to maintain passion fruit firmness

This is a report on the influence of the methods of postharvest application of CaCl2 in several concentrations, on the maintenance of the firmness of the sweet passion fruit (Passiflora alata Dryander). The fruits, picked in the pre-climateric stage, were selected desinfection with thiabendazol and submitted to CaCl2 in concentrations of 0% (control), 1%, 2%, 3% or 4% with two methods: immersion (for 2 h) and infiltration under vacuum and pressure (- 25 vacuum kPa, for 1 minute and, + 25 pressure kPa, for 1 min). All fruits were stored under refrigeration (9 degreesC, 85-90% RH), for 30 d. The fruits were evaluated for texture every 3 d. From the results, it is concluded that application of CaCl2 by infiltration favored the maintenance of fruit consistency during the first 18 days of storage. Fruits treated with 1% and 2% of CaCl2 were firmer than the others.

Comportamento de diferentes maracujazeiros em relação ao nematóide formador de galhas

Estudou-se o comportamento de diferentes espécies de maracujazeiro Passiflora spp disponíveis em nosso meio, quando inoculadas com o nematóide formador de galhas Meloidogyne incognita. As avaliações foram feitas 80 dias após a inoculação do parasito, com base nos números de galhas e de ootecas observados nos sistemas radiculares das plantas. Verificou-se que Passiflora alata, P. giberti, P. maliformis e P. serrato digitata mostraram elevada suscetibilidade, enquanto que P. caerulea, P. edulis e P. edulis f. flavicarpa foram bastante resistentes.

Production of Pseudomonas aeruginosa LBI rhamnolipids following growth on Brazilian native oils

Oils from Buriti (Mauritia flexuosa), Cupuacu (Theobroma grandiflora), Passion Fruit (Passiflora alata), Andiroba (Carapa gitianensis), Brazilian Nut (Bertholletia excelsa) and Babassu (Orbignya spp.) were evaluated as carbon sources for rhamnolipid production by Pseudomonas aeruginosa LBI. The highest rhamnolipid concentrations were obtained from Brazilian Nut (9.9 l(-1)) and Passion Fruit (9.2 g l(-1)) oils. Surface tension varied from 29.8 to 31.5 mN m(-1), critical micelle concentration from 55 to 163 mg l(-1) and the emulsifying activity was higher against toluene (93-100%) than against kerosene (70-92%). Preliminary characterization of the surfactant mixtures by mass spectrometry revealed the presence of two major components showing m/z of 649 and 503, which corresponded to the dirhamnolipid (Rha(2)C(10)C(10)) and the monorhamnolipid (RhaC(10)C(10)), respectively. The monorhamnolipid detected as the ion of m/z 503 is predominant in all samples analyzed. (c) 2005 Elsevier Ltd. All rights reserved.

Thermal properties of passion fruit juice as affected by temperature and water content

The specific heat, thermal conductivity and density of passion fruit juice were experimentally determined from 0.506 to 0.902 (wet basis) water content and temperatures from 0.4 to 68.8C. The experimental results were compared with existing and widely used models for the thermal properties. In addition, based on empiric equations from literature, new simple models were parameterized with a subset of the total experimental data. The specific heat and thermal conductivity showed linear dependency on water content and temperature, while the density was nonlinearly related to water content. The generalized predictive models were considerably good for this product but the empiric, product-specific models developed in the present work yield better predictions. Even though the existing models showed a moderate accuracy, the new simple ones would be preferred, because they constitute an easier and direct way of evaluating the thermal properties of passion fruit juice, requiring no information about the chemical composition of the product, and a reduced time of the estimation procedure, as the new empiric models are described in terms of only two physical parameters, the water content and the temperature. © Copyright 2005, Blackwell Publishing All Rights Reserved.

Meio de cultura e tipo de explante no estabelecimento in vitro de espécies de maracujazeiro

Brazil is one of the main centers of genetic variability dispersion of the Passiflora genera. Its self incompatibility as well as disease incidence in its leaves and root system and, deforestation and monocultivation, promote loss of genetic material. Considering the risk of genetic erosion, the conservation of the variability in germplasm banks, which is of great interest in plant breeding, is necessary. Studies regarding the type of expiant and concentration of the culture media are necessary in order to determine protocols of establishment and in vitro conservation of passion-fruit germplasm. The objective of the present work was to evaluate the influence of the salt and nutrient concentration in the MS culture medium and types of expiants in the establishment and growth of the Passion fruit species: Passiflora giberti N. E.Brown, P. edulis Sims and P. laurifolia L. Each Passiflora species presented its own characteristics regarding in vitro development. The complete MS medium and nodal segments the second axilliary bud promoted better development of the genotypes studied.

Aspectos biológicos de Dione juno juno (Cramer) (Lepidoptera: Nymphalidae) em genótipos de maracujazeiro

It was studied the effect of passion fruit genotypes on Dione juno juno (Cramer) (Lepidoptera: Nymphalidae) development. The experiment was carried out in a laboratory, under controlled conditions (temperature: 26 ± 1° C, RH = 60 ± 10% and photophase of 14 hours). Newly-hatched larvae were fed with leaves from different passion fruit genotypes: Passiflora edulis Sims., P. alata Dryand., P. serrato-digitata L., P. edulis f. flavicarpa Deg. ('Sul Brasil'), P. edulis f. flavicarpa, P. edulis f. flavicarpa ('Maguary FB-100') and P. foetida L. Fifty larvae from eggs collected in the field were used per genotype. Larvae were kept on passion fruits branches inside PVC tubes until pupation. Daily observations were performed and branches were replaced whenever necessary. The following parameters were evaluated: duration and viability of larval and pupal phases, larval and pupal weight and adult longevity. The experiment was arranged in randomized blocks design with seven treatments and ten replications. Data were subjected to an ANOVA and means were compared by Tukey test at 5% of probability. The least adequate genotypes for D. juno juno development were P. alata, P. serrato-digitata and P. foetida, showing a high level of antibiosis, while P. edulis, P. edulis f. flavicarpa, 'Maguary FB-100' and 'Sul Brasil' were the most suitable.

The use of the carbon-13 in the partitioning of photosynthate in vegetative and reproductive twigs of 'Sweet' passion fruit

This study's objective is to evaluate the photosynthates partitioning and source-sink relationships, in vegetative and reproductive twigs of sweet passion fruit, using the carbon-13, stable isotope of carbon. The leaves of vegetative and reproductive twigs were placed in a sealed chamber and 13CO 2 were injected for 30 minutes. After six hours, the different organs of the twig were collected and immersed in liquid nitrogen (-196°C). All plant samples were oven-dried, powdered and combusted in an elemental analyzer. The results showed that the methodology was efficient to evaluate the partitioning of photosynthates. In the vegetative twigs, the new open leaves, the closed leaves and growth meristem were the principal sink for the source leaves enriched with 13CO 2. In the reproductive twigs with only flowers buds, the source-sink relationship was changed and the flowers buds turn to be the principal sink and the growing leaves were secondary sinks. The presence of young fruits changed again the source-sink relationship of the twig, and they were the principal sinks. The apical leaves, with 60% of final leaf area were also a sink for photosynthates.

produção de mudas de maracujazeiro amarelo submetidas à salinidade em solo com biofertilizante bovino

The experiment was conducted in a greenhouse from May 1 to July 31, 2008, in Areia county, Paraiba State, PB, Brazil, in order to evaluate the effects of irrigation water salinity on initial growth of the passionfruit seedlings in non-saline substrate with and without bovine biofertilizer. The treatments were distributed in a completely randomized design, with three replications and twelve plants per plots, in a factorial arrangement 5 × 2 × 2, corresponding the former to the levels of salinity in the irrigation water: 0.5; 1.0; 2.0; 3.0 and 4.0 dS m-1, in soils with and without bovine biofertilizer applied at two moments (25 and 65 days after seedling emergence). The growth of the seedlings and the soil electrical conductivity were evaluated at the end of the experiment. The biofertilizer was diluted in a low saline water at a 1:1 ratio and was applied once two days before sowing, corresponding to 10% of the substrates volume. The increase in water salinity inhibited the growth in height of plants, leaf area and root length, but always to a lesser extent in the treatments with bovine biofertilizer. The increase in electrical conductivity of the irrigation water elevated the soil salinity, independently of the addition of biofertilizer.

Diversidade genética em maracujá amarelo utilizando marcadores moleculares fAFLP

Pós-graduação em Agronomia (Genética e Melhoramento de Plantas) - FCAV

Doses de NPK no desenvolvimento, produtividade e qualidade de frutos do maracujazeiro ‘Roxinho do Kênia'

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Qualidade e conservação pós-colheita de maracujá roxinho do kênia, sob sanitização e armazenamento

Pós-graduação em Agronomia (Horticultura) - FCA

Mancha areolada da seringueira (Hevea brasiliensis) na Amazônia: evolução do patógeno (Thanatephorus cucumeris/Rhizoctonia solani grupo de anastomose AG 2-2 Hb) num patossistema tropical

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)