Morphological and molecular characterization of the causal agent of anthracnose in tree tomato in Azuay and Loja

La antracnosis es una enfermedad fúngica que causa graves pérdidas en el cultivo de tomate de árbol en el Ecuador. La enfermedad causa graves daño en los frutos y su control se basa principalmente en la utilización de productos químicos. A nivel del Ecuador se ha reportado como causantes de la antracnosis a los géneros Colletotrichum acutatum y Colletotrichum gloeosporioides en base a características morfológicas. En el presente estudio se realizó la caracterización morfológica y molecular de 16 aislados de Colletotrichum spp. de tomate de árbol, en seis localidades diferentes en las provincias de Azuay y Loja. La caracterización morfológica se la hizo para variables tales como color de la colonia y forma del conidio, mientras que la caracterización molecular se realizó mediante la reacción en cadena de la polimerasa (PCR). La PCR se realizó con primers específicos reportados para C. acutatum y C. gloeosporioides, diseñados en el espaciador de transcripción interna (ITS). En base a la caracterización morfológica y molecular se determinó que el agente causal de la antracnosis para las provincias de Azuay y Loja es el complejo de C. acutatum, representado por C. tamarilloi. Los aislados presentaron las características propias de la especie y los análisis moleculares permitieron confirmar este resultado, generando amplificaciones de pesos moleculares de aproximadamente 500 pb, mientras que con los primers específicos de C. gloeosporioides no se obtuvo ninguna amplificación. Esta caracterización molecular confirma los resultados que ubican al complejo de C. acutatum como agente causal de la antracnosis en el Austro del Ecuador.Anthracnose is a fungal disease that causes serious losses in tree tomatoes in Ecuador. This disease causes serious damage to fruits and its control is based mainly on use of chemical products. In Ecuador, the genera Colletotrichum acutatum and Colletotrichum gloeosporioides have been reported to be the causal agent of anthracnose, based on morphological characteristics. In this study, the morphological and molecular characterization of 16 isolates of Colletotrichum spp. of tree tomato, in six different localities in the provinces of Azuay and Loja. Morphological characterization was carried out for variables such as colony color and conidium shape, while molecular characterization was performed by polymerase chain reaction (PCR). PCR experiments was carried out with specific primers reported for C. acutatum and C. gloeosporioides, designed in the internal transcription spacer (ITS). Based on morphological and molecular characterization, it was determined that the causative agent of anthracnose for the provinces of Azuay and Loja is the C. acutatum complex, represented by C. tamarilloi. Isolates presented characteristics of this species and molecular analysis allowed to confirm this result, generating amplifications of molecular weights of approximately 500 bp, while with the specific primers of C. gloeosporioides no amplification was obtained. This molecular characterization confirms results that place the C. acutatum complex as the causative agent of anthracnose in the Southern region of Ecuador

A methodology to model environmental preferences of EPT taxa in the Machangara river basin (Ecuador)

Rivers have been frequently assessed based on the presence of the Ephemeroptera— Plecoptera—Trichoptera (EPT) taxa in order to determine the water quality status and develop conservation programs. This research evaluates the abiotic preferences of three families of the EPT taxa Baetidae, Leptoceridae and Perlidae in the Machangara River Basin located in the southern Andes of Ecuador. With this objective, using generalized linear models (GLMs), we analyzed the relation between the probability of occurrence of these pollution-sensitive macroinvertebrates families and physicochemical water quality conditions. The explanatory variables of the constructed GLMs differed substantially among the taxa, as did the preference range of the common predictors. In total, eight variables had a substantial influence on the outcomes of the three models. For choosing the best predictors of each studied taxa and for evaluation of the accuracy of its models, the Akaike information criterion (AIC) was used. The results indicated that the GLMs can be applied to predict either the presence or the absence of the invertebrate taxa and moreover, to clarify the relation to the environmental conditions of the stream. In this manner, these modeling tools can help to determine key variables for river restoration and protection management.Rivers have been frequently assessed based on the presence of the Ephemeroptera— Plecoptera—Trichoptera (EPT) taxa in order to determine the water quality status and develop conservation programs. This research evaluates the abiotic preferences of three families of the EPT taxa Baetidae, Leptoceridae and Perlidae in the Machangara River Basin located in the southern Andes of Ecuador. With this objective, using generalized linear models (GLMs), we analyzed the relation between the probability of occurrence of these pollution-sensitive macroinvertebrates families and physicochemical water quality conditions. The explanatory variables of the constructed GLMs differed substantially among the taxa, as did the preference range of the common predictors. In total, eight variables had a substantial influence on the outcomes of the three models. For choosing the best predictors of each studied taxa and for evaluation of the accuracy of its models, the Akaike information criterion (AIC) was used. The results indicated that the GLMs can be applied to predict either the presence or the absence of the invertebrate taxa and moreover, to clarify the relation to the environmental conditions of the stream. In this manner, these modeling tools can help to determine key variables for river restoration and protection management

Make EU trade with Brazil sustainable

Brazil, home to one of the planet's last great forests, is currently in trade negotiations with its second largest trading partner, the European Union (EU). We urge the EU to seize this critical opportunity to ensure that Brazil protects human rights and the environment