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Marques M.W.,University of Pernambuco | Lima N.B.,University of Pernambuco | De Morais Jr. M.A.,Federal University of Pernambuco | Barbosa M.A.G.,Embrapa Semi Arido | And 4 more authors.
Fungal Diversity | Year: 2013

Mango (Mangifera indica) is a major tropical fruit species cultivated in Brazil. The objective of this study was to identify species of Lasiodiplodia associated with dieback and stem-end rot of mango in the semi-arid region of Northeastern Brazil, and compare the species in relation to mycelial growth, pathogenicity and virulence. A total of 120 isolates of Lasiodiplodia were used and identifications were made using a combination of morphology and phylogenetic analysis based on partial translation elongation factor 1-α sequence (EF1-α) and internal transcribed spacers (ITS). The following species were identified: Lasiodiplodia crassispora, L. egyptiacae, L. hormozganensis, L. iraniensis, L. pseudotheobromae, L. theobromae and Lasiodiplodia sp. Lasiodiplodia theobromae was the most frequently isolated species, which represented 41 % of all the isolates. Only this species had been previously reported on mango in Brazil, while the other species represent the first report associated with mango tree diseases in this country. Lasiodiplodia crassispora is reported for the first time associated with mango diseases worldwide. There were significant differences in mycelial growth rates among the Lasiodiplodia species and also in the optimum temperature for growth. All species of Lasiodiplodia were pathogenic on mango fruit. There were significant differences in virulence among the species, wherein L. hormozganensis and Lasiodiplodia sp.were the most virulent, while the least virulent were L. iraniensis, L. pseudotheobromae, L. crassispora and L. egyptiacae. © 2013 Mushroom Research Foundation.

Andrieu N.,CIRAD - Agricultural Research for Development | Andrieu N.,CIRDES Center International Of Recherche Developpement Sur Lelevage En Zone Sub Humide | Nogueira D.M.,Embrapa Semi Arido
Agronomy for Sustainable Development | Year: 2010

Many simulation models that are used to assess the impact of mixed farming systems have a high level of complexity that is not suitable for teaching farmers about the impacts of their practices. In this paper, we present a model that was developed and used with farmers as a discussion support tool to address the impacts of farming management strategies on farm resources. We assumed that the characterization of biomass flows at the farm level would provide a simple framework for designing a discussion support tool for farmers. The study was carried out in the semi-arid region of Brazil, where areas of native vegetation of the Caatinga Biome have been reduced in recent decades due to population pressure. In this region, simulation models are not used to discuss the impact of practices. We decided that a model for this purpose should: (1) be simple enough to be used by farmers, (2) be consistent with existing data, and (3) take into account the three main biomass management strategies. The model we built simulates biomass exports (harvest, animal intake, clearing vegetation of Caatinga), imports (purchase of fodder), and returns (animal manure) for farms with different vegetation types (Cenchrus ciliaris, Sorghum bicolour, Opuntia sp. and Caatinga native vegetation). We used the model to compare three management strategies over a 15-year period and found that the strategy that allows for the preservation of Caatinga vegetation is less sensitive to bad years but results in a reduced herd size. We validated the use of this model by testing it with farmers. We found that farmers were interested in using the model as a learning (38%), management (33%), or prospective tool (24%). This study shows that the dynamic modeling of biomass flows provides a simple and operational framework to analyze the impact of farming systems on farm resources with farmers. Contrary to current dynamic biophysical models that are based on extensive experimental data, this model does not give accurate predictions but allows both farmers and researchers to learn the impacts of farming systems. The complexity of the model should be increased progressively as farmers improve their understanding of the underlying processes. © 2009 INRA, EDP Sciences.

de Souza Leao P.C.,Embrapa Semi Arido | Motoike S.Y.,Setor de Fruticultura
Scientia Agricola | Year: 2011

The conservation and characterization of grape (Vitis spp) genetic resources in germplasm banks have been the basis of its use in breeding programs that result in development of new cultivars. There are at least 10,000 grape cultivars kept in germplasm collection. The genetic diversity in 136 table grape accessions from the state of Bahia, Brazil, was evaluated. Continuous and discrete morphoagronomic traits were assessed. The clustering analysis by the Tocher otimization method resulted in 30 clusters (considering continuous morphoagronomic traits), and 9 clusters (taking into consideration multicategorical traits). There was no agreement between clusters obtained by both, continuous or discrete phenotypic descriptors, independent of the cluster method analysis used. A satisfactory genetic variability among the table grape accessions was observed.

The effect of postharvest application of 1-methylcylopropene (1-MCP) and wax on respiratory behavior and biochemical changes was evaluated regarding the softening of soursop fruit 'Morada', during refrigerated storage. Fruits produced in Limoeiro do Norte, State of Ceara, Brazil, were harvested at the physiological maturity stage. The treatments were: control, 200 nL.L-1 of 1-MCP, Fruit wax® sprayed on fruits, and Fruit wax® sprayed on fruits followed by application of 200 nL.L-1 of 1-MCP. The fruits were stored during 0, 4, 8, 11, 13 and 15 days, at 15.4±1.1°C and 86±7% RH. A completely randomized experimental design was used, with a 4×6 factorial and four replications. From the fourth day to the eighth day, an intense metabolic activity was observed, as well as a fast starch breakdown and an increase in β-galactosidase activity. Postharvest treatments delayed or reduced respiration and ethylene production. Softening was slower in treated fruits mainly between the fourth and the eighth day. The treatment wax coating+1-MCP temporarily reduced polygalacturonase activity and kept amylase activity stable. However, wax was the most efficient treatment because it maintained the appearance during thirteen days.

de Oliveira Costa V.S.,University of Pernambuco | Michereff S.J.,University of Pernambuco | Martins R.B.,University of Pernambuco | Gava C.A.T.,Embrapa Semi Arido | And 2 more authors.
European Journal of Plant Pathology | Year: 2010

The aim of the present study was to assess diversity in the Botryosphaeriaceae on trees and fruit of mango (Mangifera indica L.) in a sequence data (ITS-1, ITS-2 and 5.8S rDNA) we confirmed the presence of Lasiodiplodia theobromae in the region, and for the first time report Fusicoccum aesculi and Neofusicoccum parvum. L. theobromae was prevalent in the Assú Valley and F. aesculi and N. parvum were in the São Francisco Valley. In fruit inoculations, L. theobromae and N. parvum were more virulent than F. aesculi. © 2010 KNPV.

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