ABSTRACT
Characterizing the diversity and structure of host-parasite communities is crucial to understanding their eco-evolutionary dynamics. Malaria and related haemosporidian parasites are responsible for fitness loss and mortality in bird species worldwide. However, despite exhibiting the greatest ornithological biodiversity, avian haemosporidians from Neotropical regions are quite unexplored. Here, we analyze the genetic diversity of bird haemosporidian parasites (Plasmodium and Haemoproteus) in 1,336 individuals belonging to 206 bird species to explore for differences in diversity of parasite lineages and bird species across 5 well-differentiated Peruvian ecoregions. We detected 70 different haemosporidian lineages infecting 74 bird species. We showed that 25 out of the 70 haplotypes had not been previously recorded. Moreover, we also identified 81 new host-parasite interactions representing new host records for these haemosporidian parasites. Our outcomes revealed that the effective diversity (as well as the richness, abundance, and Shannon-Weaver index) for both birds and parasite lineages was higher in Amazon basin ecoregions. Furthermore, we also showed that ecoregions with greater diversity of bird species also had high parasite richness, hence suggesting that host community is crucial in explaining parasite richness. Generalist parasites were found in ecoregions with lower bird diversity, implying that the abundance and richness of hosts may shape the exploitation strategy followed by haemosporidian parasites. These outcomes reveal that Neotropical region is a major reservoir of unidentified haemosporidian lineages. Further studies analyzing host distribution and specificity of these parasites in the tropics will provide important knowledge about phylogenetic relationships, phylogeography, and patterns of evolution and distribution of haemosporidian parasites.
ABSTRACT
Resumen Introducción: el bioensayo con la especie bioindicadora Daphnia magna Strauss, 1820 posibilita obtener el efecto ecotoxicológico agudo individual y en mezcla de diversos tóxicos químicos mediante la concentración letal media (CL50). Objetivo: determinar el efecto ecotoxicológico de la mezcla de aroclor 1254 y del plomo (Pb2+) sobre D. magna. Materiales y Métodos: se midió la CL50 siendo aroclor 1254 > Pb2+, y ulteriormente la concentración sin efecto ecológico (PNEC) para el efecto individual y en mezcla. Se contrastaron los valores de PNEC con la categoría 4 - E1 (lagunas y lagos) y E2 (ríos) del Estándar de Calidad Ambiental Peruano (Decreto Supremo N° 004 2017-MINAM -Perú). Resultados: los valores de CL50 disminuyeron de forma gradual a 48 h de exposición para ambos compuestos en forma individual y en mezcla. Se calculó la proporción - sinergia (PS) en relaciones de 1:1, 3:2 y 4:1 (aroclor 1254: Pb2+), obteniéndose mayores valores de PS en 3:2 y 4:1 en contrastación a 1:1. Conclusiones: la concentración de aroclor 1254 estimada de PNEC es similar al valor de la conservación del ambiente acuático categoría 4 - E1 y E2, y la concentración máxima para Pb2+ no es adecuada y debe reducirse para fortalecer la conservación de la biota acuática. Finalmente, el bioindicador D. magna determinó idóneamente la mezcla de aroclor 1254 y Pb2+.
Abstract Introduction: the bioassay with the bioindicator species Daphnia magna Strauss, 1820 makes it possible to obtain the individual acute ecotoxicological effect and in a mixture of various chemical toxics by means of the mean lethal concentration (LC50). Objective: to determine the ecotoxicological effect of the mixture of aroclor 1254 and lead (Pb2+) on D. magna. Materials and Methods: LC50 was measured with arochlor 1254> Pb2+, and subsequently the concentration without ecological effect (PNEC) for the individual effect and as a mixture. PNEC values were contrasted with category 4-E1 (lagoons and lakes) and E2 (rivers) of the Peruvian Environmental Quality Standard (Supreme Decree No. 004 2017-MINAM-Peru). Results: LC50 values gradually decreased after 48 h of exposure for both compounds individually and as a mixture. The proportion-synergy (PS) was calculated in ratios of 1:1, 3:2 and 4:1 (arochlor 1254: Pb2+), obtaining higher PS values in 3:2 and 4:1 in contrast to 1:1. Conclusions: the PNEC estimated arochlor 1254 concentration is similar to the conservation value of the aquatic environment category 4-E1 and E2, and the maximum concentration for Pb2+ is not adequate and should be reduced to strengthen the conservation of aquatic biota. Finally, the bioindicator D. magna ideally determined the mixture of aroclor 1254 and Pb2+.
Resumo Introdução: o bioensaio com as espécies bioindicadoras Daphnia magna Strauss, 1820 permite obter o efeito ecotoxicológico agudo individual e numa mistura de várias toxinas químicas por meio da concentração letal média (CL50). Objetivo: determinar o efeito ecotoxicológico da mistura de arocloro 1254 e chumbo (Pb2+) sobre D. magna. Materiais e Métodos: a CL50 foi medida com arocloro 1254>Pb2+, e posteriormente a concentração sem efeito ecológico (PNEC) para o efeito individual e como mistura. Os valores do PNEC foram contrastados com a categoria 4-E1 (lagoas e lagos) e E2 (rios) do Padrão de Qualidade Ambiental Peruano (Decreto Supremo n° 004 2017-MINAM-Peru). Resultados: Os valores de LC50 diminuíram gradualmente após 48 h de exposição para ambos os compostos individualmente e como uma mistura. A proporção-sinergia (PS) foi calculada em proporções de 1:1, 3:2 e 4:1 (arocloro 1254: Pb2+), obtendo-se valores de PS mais altos em 3:2 e 4:1 em contraste com 1:1. Conclusões: a concentração estimada de arocloro 1254 do PNEC é semelhante ao valor de conservação do ambiente aquático categoria 4-E1 e E2, e a concentração máxima de Pb2+ não é adequada e deve ser reduzida para fortalecer a conservação da biota aquática. Finalmente, o bioindicador D. magna determinou idealmente a mistura de arocloro 1254 e Pb2+.
ABSTRACT
El carbofurano es uno de los plaguicidas más empleado en la agricultura peruana. El objetivo de este trabajo fue evaluar el riesgo ambiental del carbofurano en bioensayos de toxicidad, sobre once especies no destinatarias. La siguiente secuencia relativa de mayor a menor cocientes de riesgo (CR) del carbofurano para los 19 puntos finales de efecto en once especies fue encontrada: Daphnia magna (mortalidad) > Lemna minor (inhibición de formación de las hojas) > Paracheirodon innesi (nado extraño) = P. innesi (incremento del movimiento opercular) > Chironomus calligraphus (mortalidad) > L. minor (necrosis) > P. innesi (mortalidad) > L. minor (clorosis) > Tetrapygus niger (inhibición de la fecundación) > Coturnix japonica (mortalidad) > Oncorhynchus mykiss (incremento de coloración) > Ceraeochrysa cincta (no eclosión de huevos) > O. mykiss (mortalidad con oxígeno) > O. mykiss (mortalidad sin oxígeno) > Trichogramma pretiosum (mortalidad) > C. cincta (mortalidad) > T. pretiosum (no emergencia de adultos) > Trichogramma pintoi (mortalidad) > Beauveria bassiana (inhibición del crecimiento). Los cocientes de riesgo (CR) indicaron en todos los casos un alto riesgo del carbofurano principalmente en el ambiente acuático en comparación con el terrestre.
Carbofuran is one of the most employed pesticides in Peruvian agriculture. This research aimed to evaluate the risk assessment in bioassays of carbofuran on eleven non-target species. The following relative sequence in decreasing ecotoxicity order in terms of RQ (Risk quotient) to carbofuran to 19 end points on 11 species was found: Daphnia magna (mortality) > Lemna minor (inhibition of new fronds) > Paracheirodon innesi (strange swim) = P. innesi (increase of opercula movement) > Chironomus calligraphus (mortality) > L. minor (necrosis) > P. innesi (mortality) > L. minor (chlorosis) > Tetrapygus niger (inhibition of fertilization)> Coturnix japonica (mortality) > Oncorhynchus mykiss (increase of coloration) > Ceraeochrysa cincta (not hatch of eggs) > O. mykiss (mortality without oxygen) > O. mykiss (mortality with oxygen) > Trichogramma pretiosum (mortality) > C. cincta (mortality) > T. pretiosum (not emergence of adults) > Trichogramma pintoi (mortality) > Beauveria bassiana (inhibition of growth). Risk quotient (RQ) indicated that carbofuran is highly risky mainly to aquatic environment than terrestrial.