Método de cría en laboratorio del gusano blanco de la papa Premnotrypes vorax (Coleoptera: Curculionidae)

Abstract

<p>El gusano blanco de la papa <em>Premnotrypes vorax </em>es considerado uno de los insectos plaga más limitantes del cultivo de la papa en Colombia. En este trabajo se describe un método para la cría de <em>P. vorax </em>en condiciones de laboratorio, con el que se puede obtener individuos de todos los estados de desarrollo para su uso con propósitos experimentales. Adicionalmente, se determinó la longevidad y fecundidad de los adultos para establecer el potencial de crecimiento de la cría en las condiciones evaluadas. Los adultos se mantuvieron en recipientes plásticos provistos de una capa de suelo, follaje de papa para la alimentación y pajillas para la oviposición. Las pajillas con posturas se desinfectaron y luego se incubaron en cajas de Petri en condiciones de temperatura y humedad controladas. Las condiciones más adecuadas para el mantenimiento de los individuos durante el período larva-adulto se determinaron evaluando dos tipos de alimento para las larvas, tres sustratos para pupar y tres densidades de larvas por tubérculo. Las mejores condiciones se obtuvieron con tubérculos de la variedad parda pastusa (> 80 g), sobre un sustrato de suelo esterilizado y turba en proporción 3:1 y a una densidad no mayor a diez larvas por tubérculo. Con este método de cría se podrían esperar de dos a tres generaciones del insecto por año con una tasa de incremento cercana al 17% por generación. Este método de cría se constituye en una herramienta para facilitar la realización de estudios bioecológicos del insecto y evaluar métodos para su control. </p><p> </p><p><strong>A laboratory method for rearing Andean potato weevil </strong><strong><em>Premnotrypes vorax </em></strong><strong>(Coleoptera: Curculionidae)</strong> </p><p>The Andean potato weevil, <em>Premnotrypes vorax</em>, is considered one of the most important pests of the potato crops in Colombia. In this work, a laboratory method for rearing <em>P. vorax </em>is described. All developmental stages of the insect can be obtained with this method, for experimental purposes. In addition, adult longevity and fecundity were determined for the establishment of the potential growth of the colony under the evaluated conditions. Adults were kept in plastic boxes, which were provided with a soil layer, potato leaves for feeding and dry straw for oviposition. The dry straw with egg clutches were disinfected and incubated in Petri dishes under controlled conditions of temperature and humidity. The most suitable maintaining conditions for individuals in the period from larva to adult were determined by evaluating two different feed types for larvae, three pupation substrates and three larval densities per tuber. The best conditions were obtained with potato tubers from the “parda pastusa” variety (> 80 g), on sterilized soil and peat moss in 3:1 ratio, and less those ten larvae per tuber. This rearing method can produce two or three generations per year, with an increase rate close to 17% per generation. This rearing method becomes a useful tool for bioecological studies, and to evaluate control methods for this insect. </p>

Identification of Cry toxin receptor genes homologs in a de novo transcriptome of Premnotrypes vorax (Coleoptera: Curculionidae)

“…This is one of the 14 species of potato insect pests that form part of the complex known as “Andean potato weevils” ( Fig 1 ). These insects are mainly distributed in South America, principally in Colombia, Ecuador, Venezuela, and Peru [ 4 ]. P .…”

“…This is one of the 14 species of potato insect pests that form part of the complex known as "Andean potato weevils" (Fig 1). These insects are mainly distributed in South America, principally in Colombia, Ecuador, Venezuela, and Peru [4]. P. vorax arrived in Colombia from Ecuador since 1920 at the Nariño region, and from there it was distributed through infected seeds to the most important potato crop regions in Colombia such as Boyaca ´, Antioquia and Santander [5].…”

“…It was reported that the life cycle of P. vorax can last up to nine months [8], indicating that it has only one or two generations per year. However, the average lifetime of adults is rather long since it last up to 138 ± 51.7 and 154 ± 50.7 days for males and females, respectively, allowing a very high reproduction rate, since females start oviposition at 14.4 ± 7.8 days after mating and continue up to 91.5 ± 43.0 days, with an average laid eggs of 101.3 ± 78.6 eggs and 9.6 ± 5.5 positions [4]. Historically, the control of this insect by indigenous farmers involves extended crops rotation, special separation between fields, use of plant barriers, and chemical control with highly toxic chemical insecticides such as carbamates, pyrethroids, organophosphates and carbofuran that are applied at the time of potato planting.…”

De novo transcriptome assembly of Premnotrypes vorax (Coleoptera: Curculionidae)

“…Premnotrypes vorax (Hustache) (Coleoptera: Curculionidae) is one of the 15 species of insects that form part of the complex known as "Andean potato weevil" (Figure 1). P. vorax is distributed in South America, principally in Colombia, Ecuador, Venezuela and Peru with registries as one of the most important pests of potato (Solanum tuberosum) crops (Pérez et al, 2009). Adult insects feed on the plants and cause damage along the edges of the leaves, but the larvae also make tunnel-shaped lesions in the tubers causing externally visible damage (Pérez-Álvarez et al, 2010).…”