Field Survey of Cucumber mosaic virus Subgroups I and II in Crop Plants in Costa Rica

copyright 2001 American Phytopathology Society Journals. Datos y artículo incluido por Lisela Moreira Carmona, responsable de depósitos de publicaciones del área de Patógenos y Plagas del CIBCMLeaf samples were collected from cucurbit and solanaceous crop plants and Musa spp. in 28 locations in five provinces of Costa Rica during the period from January to October 1996. Sampling sites were selected in dry, humid, and moist tropical regions ranging in altitude from 50 to 2,100 m above sea level. RNA-enriched total nucleic acid solutions were spotted onto nylon membranes and hybridized to RNA probes specific for Cucumber mosaic virus (CMV) subgroups I or II. The presence of CMV was confirmed in 13 crops in 23 of the 28 sampling sites. CMV subgroup I was found to predominate in Costa Rica. CMV subgroup II was detected in the Atlantic region only, and in only 1 out of 113 CMV-positive samples.Universidad de Costa Rica/[801-94-905]/UCR/Costa RicaUnited States Agency for International Development/[HRN-5600-G-00-2013-00]/USAD/Costa RicaUniversidad de Costa Rica/[801-95-583]/UCR/Costa RicaUCR::Vicerrectoría de Investigación::Unidades de Investigación::Ciencias Básicas::Centro de Investigación en Biología Celular y Molecular (CIBCM

Independent Evolutionary Lineages in a Globular Cactus Species Complex Reveals Hidden Diversity in a Central Chile Biodiversity Hotspot

Unraveling the processes involved in the origin of a substantial fraction of biodiversity can be a particularly difficult task in groups of similar, and often convergent, morphologies. The genus Eriosyce (Cactaceae) might present a greater specific diversity since much of its species richness might be hidden in morphological species complexes. The aim of this study was to investigate species delimitation using the molecular data of the globose cacti “E. curvispina”, which harbor several populations of unclear evolutionary relationships. We ran phylogenetic inferences on 87 taxa of Eriosyce, including nine E. curvispina populations, and by analyzing three plastid noncoding introns, one plastid and one nuclear gene. Additionally, we developed 12 new pairs of nuclear microsatellites to evaluate the population-level genetic structure. We identified four groups that originated in independent cladogenetic events occurring at different temporal depths; these groups presented high genetic diversity, and their populations were genetically structured. These results suggest a complex evolutionary history in the origin of globular cacti, with independent speciation events occurring at different time spans. This cryptic richness is underestimated in the Mediterranean flora of central Chile, and thus unique evolutionary diversity could be overlooked in conservation and management actions

Independent Evolutionary Lineages in a Globular Cactus Species Complex Reveals Hidden Diversity in a Central Chile Biodiversity Hotspot

Unraveling the processes involved in the origin of a substantial fraction of biodiversity can be a particularly difficult task in groups of similar, and often convergent, morphologies. The genus Eriosyce (Cactaceae) might present a greater specific diversity since much of its species richness might be hidden in morphological species complexes. The aim of this study was to investigate species delimitation using the molecular data of the globose cacti “E. curvispina”, which harbor several populations of unclear evolutionary relationships. We ran phylogenetic inferences on 87 taxa of Eriosyce, including nine E. curvispina populations, and by analyzing three plastid noncoding introns, one plastid and one nuclear gene. Additionally, we developed 12 new pairs of nuclear microsatellites to evaluate the population-level genetic structure. We identified four groups that originated in independent cladogenetic events occurring at different temporal depths; these groups presented high genetic diversity, and their populations were genetically structured. These results suggest a complex evolutionary history in the origin of globular cacti, with independent speciation events occurring at different time spans. This cryptic richness is underestimated in the Mediterranean flora of central Chile, and thus unique evolutionary diversity could be overlooked in conservation and management actions

Phylogenetic relationships based on nuclear and plastid DNA sequences reveal recent diversification and discordant patterns of morphological evolution of the Chilean genera of Gilliesieae (Amaryllidaceae: Allioideae)

Gilliesieae are a South American tribe of Amaryllidaceae characterized by high floral diversity. Given different taxonomic interpretations and proposals for generic and specific relationships, a representative phylogenetic analysis is required to clarify the systematics of this group. The present study provides a framework for understanding phylogenetic relationships and contributing to the development of an appropriate taxonomic treatment of Gilliesieae. Molecular analyses, based on nuclear (ITS) and plastid DNA sequences (trnL-F and rbcL), resolve with strong support the monophyly of the tribe and the differentiation of two major clades. Clade I comprises the genera Gilliesia, Gethyum and Solaria and Clade II includes Miersia and Speea. These well-supported clades are mostly congruent with vegetative and karyotype characters rather than, e.g., floral symmetry. At the generic level, all molecular analyses reveal the paraphyly of Gilliesia and Miersia. Gethyum was found to be paraphyletic, resulting in the confirmation of Ancrumia as a distinct genus. Several instances of incongruent phylogenetic signals were found among data sets. The calibrated tree suggests a recent diversification of the tribe (Pliocene–Pleistocene), a contemporary process of speciation in which instances of hybridization and incomplete lineage sorting could explain patterns of paraphyly and incongruence of floral morphology

Phenolic variation among Chamaecrista nictitans subspecies and varieties revealed through UPLC-ESI(-)-MS/MS chemical fingerprinting

Introduction Comparative analysis of metabolic features of plants has a high potential for determination of quality control of active ingredients, ecological or chemotaxonomic purposes. Specifically, the development of efficient and rapid analytical tools that allow the differentiation among species, subspecies and varieties of plants is a relevant issue. Here we describe a multivariate model based on LC–MS/MS fingerprinting capable of discriminating between subspecies and varieties of the medicinal plant Chamaecrista nictitans, a rare distributed species in Costa Rica. Methods Determination of the chemical fingerprint was carried out on a LC–MS (ESI-QTOF) in negative ionization mode, main detected and putatively identified compounds included proanthocyanidin oligomers, several flavonoid C- and O-glycosides, and flavonoid acetates. Principal component analysis (PCA), partial least square-discriminant analysis (PLS-DA) and cluster analysis of chemical profiles were performed. Results Our method showed a clear discrimination between the subspecies and varieties of Chamaecrista nictitans, separating the samples into four fair differentiated groups: M1 = C. nictitans ssp. patellaria; M2 = C. nictitans ssp. disadena; M3 = C. nictitans ssp. nictitans var. jaliscensis and M4 = C. nictitans ssp. disadena var. pilosa. LC–MS/MS fingerprint data was validated using both morphological characters and DNA barcoding with ITS2 region. The comparison of the morphological characters against the chemical profiles and DNA barcoding shows a 63% coincidence, evidencing the morphological similarity in C. nictitans. On the other hand, genetic data and chemical profiles grouped all samples in a similar pattern, validating the functionality of our metabolomic approach. Conclusion The metabolomic method described in this study allows a reliably differentiation between subspecies and varieties of C. nictitans using a straightforward protocol that lacks extensive purification steps.Universidad de Costa Rica/[809-B3-082]/UCR/Costa RicaUCR::Vicerrectoría de Investigación::Unidades de Investigación::Ciencias Básicas::Centro de Investigaciones en Productos Naturales (CIPRONA)UCR::Vicerrectoría de Docencia::Ciencias Básicas::Facultad de Ciencias::Escuela de QuímicaUCR::Vicerrectoría de Investigación::Unidades de Investigación::Ciencias Básicas::Centro de Investigación en Biología Celular y Molecular (CIBCM)UCR::Vicerrectoría de Docencia::Ciencias Básicas::Facultad de Ciencias::Escuela de Biologí

Standardized genetic diversity-life history correlates for improved genetic resource management of Neotropical trees

Aim Life history traits and range size are key correlates of genetic diversity in trees. We used a standardized sampling protocol to explore how life history traits and range size relate to the magnitude, variance and structuring (both between- and within-population) of genetic diversity in Neotropical tree species. Location The Neotropics Methods We present a meta-analysis of new population genetic data generated for 23 Neotropical tree species (=2,966 trees, 86 populations) across a shared and broad geographic area. We compared established population genetic metrics across these species (e.g., genetic diversity, population structure, fine-scale genetic structure), plus we estimated the rarely used variance in genetic diversity among populations. We used a multivariate, maximum likelihood, multimodel inference approach to explore the relative influence of life history traits and range size on patterns of neutral genetic diversity. Results We found that pioneer and narrow range species had lower levels but greater variance in genetic diversity—signs of founder effects and stronger genetic drift. Animal-dispersed species had lower population differentiation, indicating extensive gene flow. Abiotically dispersed and pioneer species had stronger fine-scale genetic structure, suggesting restricted seed dispersal and family cohort establishment. Main conclusions Our multivariable and multispecies approach allows ecologically relevant conclusions, since knowing whether one parameter has an effect, or one species shows a response in isolation, is dependent on the combination of traits expressed by a species. Our study demonstrates the influence of ecological processes on the distribution of genetic variation in tropical trees, and will help guide genetic resource management, and contribute to predicting the impacts of land use change

Genetic analysis of the dry forest timber tree Sideroxylon capiri in Costa Rica using AFLP

Sideroxylon capiri (“Tempisque”) is a threatened and economically important timber species in the dry forest of Costa Rica. To assess the extent of the genetic diversity between and within populations of this species, 86 samples were obtained from four sites in the northwestern part of the country from protected and non-protected areas. They were analyzed by amplified fragment length polymorphism. Five primers were used to generate 254 polymorphic bands. Molecular variance indicated a 92 % within locations with a PhiPT (φ st) of 0.083 and a He from 0.204 to 0.249. PCoA analysis showed two different groups: one formed by Palo Verde and La Cruz samples, and another group with Nicoya and Barra Honda samples. The dendrogram arranged the samples in three groups: individuals from Palo Verde and La Cruz divided in two groups, and a more compact group from Barra Honda and Nicoya. A positive correlation between pairwise linearized geographical distance and genetic differentiation among populations was detected by Mantel test (R 2 = 0.76241, P = 0.04). Results are discussed in terms of fragmentation of the continuous forests and geographical barriers. Despite these results, it is evident that a great genetic diversity exists for this species and the results can be used for conservation purposes.Universidad de Costa Rica/[]/UCR/Costa RicaConsejo Nacional para Investigaciones Científicas y Tecnológicas/[]/CONICIT/Costa RicaUCR::Vicerrectoría de Investigación::Unidades de Investigación::Ciencias Básicas::Centro de Investigación en Biología Celular y Molecular (CIBCM)UCR::Vicerrectoría de Docencia::Ciencias Básicas::Facultad de Ciencias::Escuela de QuímicaUCR::Vicerrectoría de Docencia::Ciencias Básicas::Facultad de Ciencias::Escuela de Biologí