Analysis of antenal sensilla patterns of Rhodnius prolixus from Colombia and Venezuela

Antennal sensilla patterns were used to analyze population variation of domestic Rhodnius prolixus from six departments and states representing three biogeographical regions of Colombia and Venezuela. Discriminant analysis of the patterns of mechanoreceptors and of three types of chemoreceptors on the pedicel and flagellar segments showed clear differentiation between R. prolixus populations east and west of the Andean Cordillera. The distribution of thick and thin-walled trichoids on the second flagellar segment also showed correlation with latitude, but this was not seen in the patterns of other sensilla. The results of the sensilla patterns appear to be reflecting biogeographic features or population isolation rather than characters associated with different habitats and lend support to the idea that domestic R. prolixus originated in the eastern region of the Andes.Fil: Esteban, Lyda. Universidad Industrial de Santander; ColombiaFil: Angulo, Víctor Manuel. Universidad Industrial de Santander; ColombiaFil: Dora Feliciangeli, M.. Universidad de Carabobo; VenezuelaFil: Catala, Silvia Susana. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Regional de Investigaciones Científicas y Transferencia Tecnológica de La Rioja. - Universidad Nacional de La Rioja. Centro Regional de Investigaciones Científicas y Transferencia Tecnológica de La Rioja. - Universidad Nacional de Catamarca. Centro Regional de Investigaciones Científicas y Transferencia Tecnológica de La Rioja. - Secretaría de Industria y Minería. Servicio Geológico Minero Argentino. Centro Regional de Investigaciones Científicas y Transferencia Tecnológica de La Rioja. - Provincia de La Rioja. Centro Regional de Investigaciones Científicas y Transferencia Tecnológica de La Rioja; Argentin

Microorganisms and spatial distribution of the sinkholes of the Yucatan Peninsula, underestimated biotechnological potential?

Investigación basada en el potencial bio-tecnológico de las micro-especies que habitan los cenotes de la Península de YucatánAbstract Objective: To detect the spatial distribution of the sinkholes of the Peninsula of Yucatan (SPY) and identify those cenotes where microorganisms have been registered. Methods: The geographic coordinates of the SPYs were obtained from various databases, as well as from scientific publications relating to the terminology ‘sinkholes’, ‘karst systems’ and ‘cenotes’. All coordinates were transformed into the Universal Transverse Mercator reference system (UTM) with datum WGS84. An infrared composite image was created with 432 RGB bands from the Landsat 8 satellite. The points with the location of the cenotes were imported into the Software TerrSet. Results: Total 1026 coordinates of sinkholes were recorded in the Yucatan Peninsula. In 18 sinkholes (<2%), microorganisms have been recovered and identified in various taxonomic levels, and only 6 sinkholes (<0.6%) has their biotechnological potential been evaluated. Conclusions: The microorganisms that inhabit the sinkholes of the Yucatan Peninsula are a reservoir with practically unexplored biotechnological potential.CONACY

Microorganismos acuáticos: una farmacia por visitar

Microbial metabolites represent a large source of biological products with potent and diverse bioactivities. Two of the most prolific groups of microbial metabolites are actinomycetes and filamentous fungi isolated from soil. Aquatic microorganisms recently have emerged as an entirely new source of species capable of biosynthesizing metabolites with new structures. In this context, tropical fungi are being incorporated into screening programs as potential producers of drugs with new action modes to target sites.Los metabolitos microbianos ofrecen diversas actividades biológicas. Dos de los más prolíferos grupos productores de metabolitos bioactivos son los actinomicetos y los hongos filamentosos aislados de suelos. Los microorganismos acuáticos han emergido recientemente como una fuente de especies capaces de biosintetizar metabolitos con estructuras novedosas. En este contexto los hongos tropicales se están incorporando a los programas de preselección como potenciales productores de fármacos con nuevos modos de acción

Microorganismos acuáticos: una farmacia por visitar

Microbial metabolites represent a large source of biological products with potent and diverse bioactivities. Two of the most prolific groups of microbial metabolites are actinomycetes and filamentous fungi isolated from soil. Aquatic microorganisms recently have emerged as an entirely new source of species capable of biosynthesizing metabolites with new structures. In this context, tropical fungi are being incorporated into screening programs as potential producers of drugs with new action modes to target sites.Los metabolitos microbianos ofrecen diversas actividades biológicas. Dos de los más prolíferos grupos productores de metabolitos bioactivos son los actinomicetos y los hongos filamentosos aislados de suelos. Los microorganismos acuáticos han emergido recientemente como una fuente de especies capaces de biosintetizar metabolitos con estructuras novedosas. En este contexto los hongos tropicales se están incorporando a los programas de preselección como potenciales productores de fármacos con nuevos modos de acción

Activity of Eugenia winzerlingii Standl extracts on Bemisia tabaci Gennadius (Hemiptera: Aleyrodidae)

The whitefly (Bemisia tabaci Genn.) is a widely distributed and highly harmful plant pest. Selection of resistant populations to chemical pesticides exacerbated the whitefly problem in many crop productions. Currently, there is enormous impetus for the development of natural alternatives to manage B. tabaci. Eugenia winzerlingii (Myrtaceae) is an endemic plant located in southern México. Previous studies have shown that ethanol extracts of leaves have nematicidal and repellent properties against Meloidogyne incognita and Myzus persicae. Therefore, the objective of this study was to determine the repellent and insecticidal effect of aqueous and organic extracts of E. winzerlingii leaves against eggs, nymphs and adult whiteflies, under laboratory conditions. On B. tabaci eggs, the aqueous extract was the most active. This extract showed values of 0.21 and 1.29 % w/v for LC50 and LC90, respectively. In contrast, B. tabaci nymphs were affected only by organic extracts. In this regard, the ethyl acetate extract showed the lowest values for LC50 and LC90 (0.25 and 3.10 mg mL-1, respectively. This extract was also the most active against adult settling, where more than 80% inhibition was observed. To the best of our knowledge no reports on insecticidal activity or chemical constituents of E. winzerlingii have been reported. This plant species might be considered a good candidate for natural sources of insecticides to manage whitefly