Tecia solanivora (Lepidoptera: Gelechiidae) is an invasive potato pest of the north of South America that recently colonized zones where Phthorimaea operculella (Lepidoptera: Gelechiidae), a taxonomically related insect, was established. Nowadays, both species can be found in most areas in different proportions. The Phthorimaea operculella granulovirus (PhopGV) was found to efficiently control P. operculella and was used as a biopesticide in storage conditions. However, no appropriate biological control methods exist for T. solanivora, and the use of granulovirus isolates would provide a solution. The Colombian Corporation for Agricultural Research (CORPOICA) carried out several T. solanivora larva samplings in Colombia with the aim of finding potential isolates. Five geographical granulovirus isolates from T. solanivora (VG001, VG002, VG003, VG004, and VG005) were found, and molecular analysis by REN profiles shows three different genotypic variants in Colombia. Analysis of their genomes revealed their relatedness to PhopGV. Two isolates exhibited submolar bands in their REN patterns, suggesting a mixture of viral genotypes. These data were confirmed by PCR amplification and sequencing of particular regions of the viral genomes. Their biological activity was assayed on both hosts, T. solanivora and P. operculella. A significantly higher pathogenicity in both hosts was observed with isolates VG001 and VG005 than with isolate VG003 or a Peruvian isolate (from P. operculella) used as a reference in the bioassay. Based on their molecular and biological activity characteristics, VG001 and VG005 isolates should be selected for further analysis in order to establish their potential as biological control agents.

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Bemisia tabaci es una plaga de importancia económica debido a su amplia distribución geográfica, al daño que ocasiona, y al gran número de cultivos que afecta. En Colombia el control biológico mediante el uso de bioplaguicidas surge como una alternativa promisoria para programas de manejo integrado de plagas. Por esta razón, el objetivo del presente trabajo fue desarrollar y evaluar preformulados con base en hongos entomopatógenos nativos contra B. tabaci. Se evaluaron diferentes sustratos para la producción masiva de los aislamientos Bv 056 de Beauveria bassiana, Pc 013 de Paecilomyces sp. y Vl 026 de Lecanicillium lecanii. Se seleccionó como el de mayor rendimiento y fácil manipulación un sustrato sólido con base en cereales que presentó un rendimiento promedio de 1x109  conidios/g. El principio activo del bioplaguicida consistente en los conidios separados del medio de cultivo fue caracterizado microbiológica y físicamente. Se evaluó bajo condiciones de laboratorio el efecto de los preformulados sobre ninfas de segundo instar, infestando foliolos de fríjol y aplicándolos a una concentración de 1x108 conidios/mL. Se produjo el mayor porcentaje de eficacia con el preformulado a base de B. bassiana con un 96,5% a los 14 días postaplicación, seguido por los preformulados de Paecilomyces sp. y L. lecanii, con 81,8% y de 70%, respectivamente.

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Diatraea spp. (Lepidoptera: Crambidae) are a group of insects that are agriculture pests in many economically relevant crops such as sugarcane, sorghum, corn and rice. Recognized species for this genus respond differentially to natural enemies used in their biological control, emphasizing the importance of species in a regional approach. Currently, identification is based on the male genitalia. However, the availability of specimens collected from field and subjectivity based on the character recognition can seriously hamper species identification, and therefore result in inadequate pest management. To overcome this, individuals of Diatraea spp. preliminarily classified male genitalia and obtained from reared conditions and the field (both derived from natural populations occurring in Colombia) were analyzed using genitalic morphometry and molecular biology specifically using a fragment of the cytochrome oxidase subunit II (CO II) mitochondrial gene. Although morphometric analysis did not show any overriding results regarding genitalia morphology, the bioinformatics analyses of CO II sequences resulted in an adequate classification of the individuals within the recognized species. It also, revealed that the occurrence of clades associated with geographical distribution may be associated with cryptic species. The latter was also confirmed by a Single-Strand Conformation Polymorphism (SSCP) methodology evaluating the same fragment of CO II. This experimental approach allows properly recognizing each species and in consequence is proposed as an effective tool in Diatraea species identification.