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[en] The immune system maintains the integrity of the organisms through a complex network of molecules, cells, and tissues that recognize internal or external antigenic substances to neutralized and eliminate them. The mechanisms of immune response have evolved in a modular fashion, where members of a given module interact strongly among them, but weakly with members of other modules, providing robustness and evolvability to the immune system. Ancestral modules are the raw material for the generation of new modules through evolution. Thus, the study of immune systems in basal metazoans such as cnidarians seeks to determine the basic tool kit from which the metazoans started to construct their immune systems. In addition, understanding the immune mechanisms in cnidarians contributes to decipher the etiopathology of coral diseases of infectious nature that are affecting coral reefs worldwide.
[en] Bactrocera carambolae Drew and Hancock is a quarantine pest present in Brazil and is the main phytosanitary barrier for the export of fresh fruits from that country. In this work, we evaluated the effect of Amazonian isolates of Metarhizium on kill larvae, pupae, and adults of B. carambolae in soil applications. The mortality of larvae and pupae in sterile soil treated with Metarhizium anisopliae was 70 %. In addition, 100 % of the adults that emerged from this substrate died up to five days later. This isolate caused the mortality of larvae and pupae in non-sterile soil, but its effect was more evident after adult emergence (70 % mortality up to ten days after emergence). Metarhizium robertsii was effective in killing larvae and pupae of the pest, especially in non-sterile soil, and caused a 60 % reduction in adult survival 50 days after emergence. These results indicated the possible use of these isolates for the control of B. carambolae, suggesting the possibility of using this biocontrol mode as another alternative in controlling this quarantine pest.
[en] The origin and evolution of the term guild are analyzed, as well as its application in ecology, considering the multiple connotations that have been given and the confusion that has been generated by using it improperly. Likewise, the importance of homogenizing the terms and clearly defining the guilds is discussed, to have a language that allows understanding the scope of the term without ambiguities. The use of the term, as well as its persistence in ecological studies, suggests that it has considerable relevance depending on the form and the way it is used. The inappropriate or derivative use of this term is risky and dangerous since it tends to reduce the term to an empty word with multiple meanings. Also, this trivialization constitutes a threat to the proper use of the guild concept in ecology and its meaning as a whole.
[en] Endophyte microorganisms have great biotechnological interest, with features applicable to different areas and are potentially useful in agriculture. The current study determines the biotechnological potential of endophytic fungi, isolated from leaves of Sapindus saponaria, to control phytopathogenic fungi and evaluate their enzyme production. Molecular taxonomy was performed by sequencing of the ITS1-5.8S-ITS2 ribosomal DNA region, identifying the genera Phomopsis, Sordariomycetes, Diaporthe, and Colletotrichum. In vitro antagonism against phytopathogens showed better results against Fusarium solani and provided inhibition indices between 41.8 % and 67.5 %. The endophytic strain SS81 (Diaporthe citri) presented the highest antagonism index against the pathogen. Against Glomerella sp. and Moniliophthora perniciosa, inhibition rates ranged between 18.7 % and 57.4 % and between 38.3 % and 64.8 %, respectively. Enzyme assays revealed that strain SS65 (Diaporthe sp.) produced 1.16 UI μmol/min of amylase; strain SS77 (Diaporthe sp.) produced 2.74 UI μmol/min of pectinase, and strain SS08 (Diaporthe sp.) produced 1.51 UI μmol/min of cellulase. Thus, the current study shows evidence the importance of isolated endophytes with phytoprotective properties of plants with medicinal properties as alternatives for biological control and natural sources of products with biotechnological interest.
[en] The determination of Chlamydia psittaci (Cp) in psittacida birds in zoological parks in Venezuela represents a strategy of conservation and preservation for this group of birds, where multiple species are threatened with extinction and others have lost their capacity of reincorporation to their natural habitat. Through the nested polymerase chain reaction (PCR) the 16S subunit of Cp DNAr was amplified in 50 cloacal swab samples from psittacine birds, reporting a frequency of 62 %. The work was carried out in the Zoo Park Las Delicias (PZD) 8% and the Aquarium of Valencia (AV) 54%. The high frequency was associated with a genotype of low concentration and virulence due to the absence of clinical signs of avian chlamydiosis. These results demonstrate the need to promote the detection of Cp, mainly for the AV that acts as a center of reception of specimens of confiscation, and, like the PZD, have other species vulnerable to extinction with risk of infection to Cp.
[en] Open coal mining will cause a series of modifications to different lotic environments in Colombia. In this paper we analyzed the case of an open pit coal mine located in the Department of La Guajira, Colombia, focusing on the state of knowledge of the ichthyofauna, the potential effects of modifications on aquatic communities and the effectiveness of restoration/compensation measures. To assess the state of knowledge of the ichthyofauna, we reviewed relevant literature and used the ICE species richness estimator. To identify the potential effects of the modifications on aquatic biota and the effectiveness of the restoration/compensation measures, we carried out a literature review. We found that about 42 % of the fish species in the Rancheria River basin and the mining concession area are still unknown. Furthermore, related studies indicate that the modifications will negatively affect the physical characteristics of the channels and consequently, the structure and function of the aquatic biota. Although we advise the non-intervention of the lotic systems, we propose some recommendations under an intervention scenario, such as conducting research addressing different facets of biodiversity, publication of results in refereed journals, public access to data, among others. We concluded if the economic benefit derived from coal mining prevails over the aquatic environments preservation there will be a loss of functions and ecological services that are indispensable for the human well-being and the ecosystem balance.
[en] We analyzed the contribution of particulate organic matter to the spring Canaverales (La Guajira, Colombia) over a period of six months (dry and rainy). The monthly litterfall was 0.17 t-ha-1-month-1, which represented 2.08 t-ha-1 year-1 when extrapolated to one year. This is an intermediate value with respect to others reported from tropical dry forests. The correlation between litter production and precipitation was statistically significant. Litterfall was dominated by the leaf fraction (66.61 %), followed by the reproductive material (15.92 %), the woody (11.12 %) and miscellaneous materials (6.36 %). The highest production of leaf litter was registered for Prosopis juliflora (1.31 t-ha-1 year1) and the lowest for Brosimum alicastrum (0.46 t-ha year1). P. juliflora and Anacardium excelsum, presented the major contributions of foliar leaf litter, what suggests they could be potential species for inclusion in restoration activities in riparian areas. P. juliflora was the species that presented the highest rates of litter decomposition (0.242 year1), while the Sterculia apetala was the most persistent (0.079 year-1). The results indicate that litterfall and litter decomposition rates depend on forest composition and climatic variations.
[en] Forensic entomology is a discipline that uses insects to obtain useful information for the determination of the postmortem interval (PMI). Flies of the family Calliphoridae are extensively used for this purpose; however, the identification of these flies can be difficult when the individual is not an adult or when it is incomplete. In the present work, we tested the utility of the ITS2 region of the nuclear genome for the identification of Calliphoridae species in Colombia using three approaches: comparing genetic distances using the barcoding methodology, with a phylogenetic reconstruction, and with PCR-RFLPs. We sequenced 520 bp in 44 individuals belonging to 16 species of califorids. Intraspecific and interspecific distance values were calculated using the K2P model. The intraspecific distance values ranged between 0 and 0.252 %, while the interspecific distance values ranged between 3.6 and 18.9 %, indicating that this gene can be used as a genetic barcode for the identification of species of the Calliphoridae family. Both the Neighbour-Joining and Bayesian analyses recovered 90 % of the genera as monophyletic, with pp values between 0.89 and 1. Blepharicnema splendens was always recovered within the Lucilia genera. Based on the obtained sequences we used the NEBCutter application to identify four restriction enzymes that cut in a differential way and generated useful patterns for the identification of the species. The enzymes were successfully tested and confirmed the utility of this technique as a fast way to identify species of Calliphoridae in Colombia.
[en] In tropical streams organic matter is the principal source of energy for the communities in the river. Main components of organic matter are coarse-particulate organic matter (CPOM) and fine particulate organic matter (FPOM). Therefore, transport of CPOM and FPOM and its relationship with some physical and chemical variables was evaluated, on three sections of an altitudinal gradient from 50 to 1700 masl during a daily-cycle at Gaira River. Samples were taken monthly from March to June 2008.-it was observed significant differences in drift of CPOM between stations. station 2 (middle part), first sample, recorded the highest value (474 kg m-3) and station 3 showed the lowest lower value of drift biomass (0.26 kg m-3) during the study. FPOM showed similar values during all the sampling (0.58 - 6.34 g m-3). However, significant differences were detected between sampling three and four. Transport of FPOM decreased with the increase of precipitation. An inverse relationship between water velocity and transport of CPOM was observed, while the FPOM, showed constant values. These results are partiality similar to reported in the literature, because the dynamic of transport of OM is relationship with local variations environmental.
[en] The traceability of the recovery process of The High Andean Forests of the Cerros Orientales affected by forest fires and gorse, through conceptual models is presented. Do this information on meteorological, vegetation, social and institutional variables were reviewed, which has allowed to characterize the disturbances and their influence on this ecosystem. In the first model, the total affectation of High Andean Forests was described under a scenario of forest fire and gorse, where the vegetation component is the main fuel for the generation and propagation of fire; the consequences of the event come from the alteration in the generation of ecosystem services to the changes in the ecological succession. The second model corresponds to the transition model, where the actions that must be included for the restoration of the ecosystem are presented. Among them, there are the ecological restoration processes; such as the integrated management of the soil, the recomposition of vegetation coverage, the management and control of exotic species and the approaches between environmental institutions and the community. The third model refers to an optimum scenario for a restored ecosystem, where all the components have been restored, there is an appropriate ecological succession and an appropriation of the Cerros Orientales is produced to work as both goods and services generators. Finally, a series of conclusions that will allow coming up with the generation of models for eventual restoration processes are proposed, as well as the guidelines for the management of exotic species and the inter-institutional issues approach.