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Puerto Bolívar, Ecuador

Leroy T.,CIRAD - Agricultural Research for Development | De Bellis F.,CIRAD - Agricultural Research for Development | Legnate H.,British Petroleum | Musoli P.,COREC | And 4 more authors.
Genetica | Year: 2014

The management of diversity for conservation and breeding is of great importance for all plant species and is particularly true in perennial species, such as the coffee Coffea canephora. This species exhibits a large genetic and phenotypic diversity with six different diversity groups. Large field collections are available in the Ivory Coast, Uganda and other Asian, American and African countries but are very expensive and time consuming to establish and maintain in large areas. We propose to improve coffee germplasm management through the construction of genetic core collections derived from a set of 565 accessions that are characterized with 13 microsatellite markers. Core collections of 12, 24 and 48 accessions were defined using two methods aimed to maximize the allelic diversity (Maximization strategy) or genetic distance (Maximum-Length Sub-Tree method). A composite core collection of 77 accessions is proposed for both objectives of an optimal management of diversity and breeding. This core collection presents a gene diversity value of 0.8 and exhibits the totality of the major alleles (i.e., 184) that are present in the initial set. The seven proposed core collections constitute a valuable tool for diversity management and a foundation for breeding programs. The use of these collections for collection management in research centers and breeding perspectives for coffee improvement are discussed. © 2014 Springer International Publishing Switzerland. Source

Rivano F.,CIRAD - Agricultural Research for Development | Mattos C.R.R.,Michelin | Cardoso S.E.A.,Michelin | Martinez M.,Technical State University of Quevedo | And 3 more authors.
Industrial Crops and Products | Year: 2013

The CIRAD-Michelin-Brazil (CMB) breeding program was set up in 1992 and has produced several genotypes as alternative varieties for growing in suboptimal regions and areas affected by South American Leaf Blight (SALB). From a large parent population of more than 113 clones, the program developed CMB genotypes evaluated in large-scale clone trials. Based on accurate knowledge of the parents' agronomic potential, the CMB breeding program combined family and individual selection in the seedling evaluation trials. The segregation ratios of the SALB resistance traits in the progeny were used to identify and reject parents whose resistance was determined by a small number of genes, easily overcome by Microcyclus ulei strains. After evaluating the germplasm, 13 genotypes were selected for evaluation of their resistance, girth and rubber production in a trial network covering eight sites in Brazil and Ecuador. There were significant differences between clones, sites and clone-site interactions. The resistance of the clones to SALB was confirmed for all sites, both for conidial and sexual fungal stages. The growth rate in Ecuador was always higher than in Brazil with the exception of one clone. Data from previous years of production for a few clones was used to estimate the potential yield of these clones compared to clones usually planted in Latin America. Simultaneous selection for SALB resistance, yield and growth resulted in promising genotypes which need to be tested in areas with different environments. © 2012 Elsevier B.V. Source

Paz-Carrasco L.C.,Federal University of Vicosa | Castillo-Urquiza G.P.,Federal University of Vicosa | Lima A.T.M.,Federal University of Vicosa | Xavier C.A.D.,Federal University of Vicosa | And 3 more authors.
Archives of Virology | Year: 2014

Viral diseases caused by begomoviruses are of economic importance due to their adverse effects on the production of tropical and subtropical crops. In Ecuador, despite reports of significant infestations of Bemisia tabaci in the late 1990s, only very recently has a begomovirus, tomato leaf deformation virus (ToLDeV, also present in Peru), been reported in tomato. ToLDeV is the first monopartite begomovirus discovered that originated in the Americas, and its presence in Ecuador highlights the need for a wider survey of tomato-infecting begomoviruses in this country. Tomato and weed samples were collected in 2010 and 2011 in six provinces of Ecuador, and begomovirus genomes were cloned and sequenced using a rolling-circle-amplification-based approach. Most tomato samples from the provinces of Guayas, Loja, Manabi and Santa Elena were infected with tomato leaf deformation virus (ToLDeV). One sample from Manabi had a triple infection with ToLDeV, rhynchosia golden mosaic Yucatan virus (RhGMYuV) and an isolate that was a recombinant between the two. A new begomovirus was detected in another tomato sample from Manabi. Samples of Rhynchosia sp. from the provinces of Guayas and Manabi were infected by RhGMYuV. These results indicate not only the prevalence of ToLDeV in tomato in Ecuador but also the presence of other viruses, albeit at a much lower frequency. © 2014 Springer-Verlag Wien. Source

Hue C.,Valrhona SA | Brat P.,CIRAD - Agricultural Research for Development | Gunata Z.,Montpellier University | Samaniego I.,INIAP | And 5 more authors.
Journal of Agricultural and Food Chemistry | Year: 2014

Flavan-3-ols were successfully extracted from cocoa by the Fast-Prep device and analyzed by HPLC-DAD, and their identifications were confirmed by injection of authentic standards. (-)-Epicatechin was the most abundant component with an average of 9.4 mg/g dried cocoa powder. More than 700 cocoa samples were used to calibrate the NIRS. An efficient calibration model was developed to accurately determine any flavan-3-ol compound of ground dried cocoa beans (SEP = 2.33 mg/g in the case of total flavan-3-ols). This performance enabled NIRS to be used as an efficient and easy-to-use tool for estimating the level of targeted compounds. The analysis of the PLS loadings of the model and pure epicatechin spectra gave proof that NIRS was calibrated on an indirect strong correlation resulting in the changes in flavan-3-ols during fermentation and their interaction with some major components, such as proteins. Total flavan-3-ol concentration fell from an average of 33.3 mg/g for unfermented samples to an average of 6.2 mg/g at the end of fermentation. Changes in flavan-3-ol content were dependent upon the origin and highly correlated to the fermentation level expressed as the sum of temperatures (average R2 = 0.74), a good marker of the fermentation process and of the heterogeneity of the batch. © 2014 American Chemical Society. Source

Navarrete B.,INIAP | McAuslane H.,University of Florida | Deyrup M.,Archbold Biological Station | Pena J.E.,University of Florida
Florida Entomologist | Year: 2013

After the arrival of the Asian citrus psyllid Diaphorina citri Kuwayama (Hemiptera: Psyllidae) in Florida, several studies mentioned the presence of ants where D. citri was present, but there was no clarification of their specific interaction with the psyllid. The goal of this study was to elucidate the role of ants in the biological control of D. citri by observing ant behavior and by determining if ant presence, modified by exclusion manipulations, affected parasitism of D. citri by Tamarixia radiata (Waterston, 1922) (Hymenoptera: Eulophidae), an introduced parasitoid of the psyllid, when the insect was infesting orange jasmine, Murraya paniculata (L.) Jack (Sapindales: Rutaceae) and Persian lime, Citrus latifolia Tanaka (Sapindales: Rutaceae). During a preliminary survey on M. paniculata in Homestead, Florida, we observed 2 ant species in association with D. citri, i.e., the big headed ant, Pheidole megacephala Fabricius, and the rover ant, Brachymyrmex obscurior Forel. In 2 ant exclusion experiments, using a 2-cm-wide barrier of Tanglefoot®, P. megacephala was the only ant species found in M. paniculata while P. megacephala, B. patagonicus and Solenopsis invicta Buren were observed in C. latifolia. The number of P. megacephala found in the unprotected flushes in M. paniculata fluctuated between 0.15 and 0.5 per flush while in C. latifolia the number of ants, pooled across species, varied between 1.44 and 6.61. In M. paniculata flushes from Tanglefoot-treated plants, 20.36% of the nymphs were parasitized by T. radiata compared to 0.39% parasitism in untreated control flushes where ants had not been excluded. Fifty-eight percent of the psyllid nymphs were parasitized in the C. latifolia Tanglefoot® ant-exclusion flushes compared with 8.57% parasitism in the non-exclusion control. An additional experiment using the ant bait Extinguish Plus® (Hydramethylnon 0.365%+ S-Methoprene 0.250%) applied to the soil surrounding the trunk showed that the use of a granular bait can help to reduce ant populations and consequently increase the percentage parasitism of the Asian citrus psyllid. Source

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