Juan Fernando Solís-Aguilar

Genitalia of three species of Heilipus Germar (Coleoptera: Curculionidae) that damage avocado fruits (Persea americana Mill.) in Mexico and Costa Rica

The male and female genitaliae of three species of the genus Heilipus Germar (H. lauri Boheman, H. pittieri Barber and H. trifasciatus Fabricius) that damage avocado fruits (Persea americana Mill.) in Mexico and Costa Rica are described and illustrated. The aedeagus, spiculum gastrale, styli of 8th sternite are different in each one of the three species studied and can be used for specific identification.

Effect of the Height and Distribution Pattern of Pheromone-Baited Traps on the Capture of Scyphophorus acupunctatus (Coleoptera: Dryophthoridae) on Blue Agave (Asparagales: Asparagaceae)

Summary The effect of height and distribution pattern of traps on the capture of Scyphophorus acupunctatus Gyllenhal (Coleoptera: Dryophthoridae) on blue agave (Asparagales: Asparagaceae) in commercial plantations was studied. Results showed that the trap height and the distribution pattern did not have an effect on the number of captured weevils per trap. In contrast, the inter-trap distance had an effect on the number of captured weevils per trap. For monitoring this weevil in blue agave commercial plantations, we recommend to use the pheromone and agave tissue-baited traps placed at ground level, at 200 m distance between traps, and distributed in a square distribution pattern.

Attraction range and inter-trap distance of pheromone-baited traps for monitoring Scyphophorus acupunctatus (Coleoptera: Dryophthoridae) on blue agave

Abstract Scyphophorus acupunctatus Gyllenhal (Coleoptera: Dryophthoridae) is one of the most important insect pests of wild and cultivated agaves in Mexico. For managing this weevil, it is important to have a method for detecting and sampling its population density. The weevils life cycle takes place inside the agave plant, which makes sampling of the weevil difficult. The use of traps baited with synthetic pheromone plus agave tissue is a useful tool for sampling the population density of this pest. Using the capture-mark-release-recapture method, we investigated the attraction range of traps baited with synthetic pheromone plus agave tissue to capture S. acupunctatus. We also evaluated several inter-trap distances to determine the best density of traps for monitoring this insect. Our results showed that these traps attracted S. acupunctatus up to a range of 120 m. In addition, we found that the cardinal point at which weevils were released affected their recapture. The results also showed that, in general, experiments with the longest inter-trap distances captured the most weevils. Thus, traps placed at 100 m in the 1st experiment, 200 m in the 2nd experiment, and 250 m in the 3rd experiment captured more weevils than traps placed at shorter distances. Based on our results of attraction range and inter-trap distances, we suggest that these pheromone-baited traps could be used for monitoring S. acupunctatus at densities of 1 trap per 6 ha of blue agave crop.

Amount and Bagging of the Bait Food Affect the Captures of Scyphophorus acupunctatus (Coleoptera: Curculionidae) by Pheromone-Baited Traps

Abstract The weevil Scyphophorus acupunctatus Gyllenhal (Coleoptera: Cuculionidae) is the most important insect pest of wild and cultivated agaves worldwide. This weevil causes direct damage while feeding and egg laying on host plants, and indirect damage due to the wounds on agave tissue that may serve as an entry for plant pathogens. Sampling and control of this weevil is complicated because of its cryptic habits. Thus, the use of synthetic aggregation pheromone-baited traps may be a useful tool for monitoring or control of this pest. The attraction of agave weevil to pheromone traps is synergized by the presence of host plant tissue. In this study, we evaluated the effect of the amount of fresh agave tissue and bagging of the plant tissue on the capture of S. acupunctatus with pheromone-baited traps in a blue agave crop. The highest captures of weevils were obtained in traps baited with the synthetic pheromone plus 400 g of agave tissue. Weevil capture rate was increased when the food bait was placed into a plastic bag or plastic container with holes as compared with unbagged food bait.

Evaluación en Campo de Insecticidas Sobre Melanaphis sacchari (Zehntner)1 en Sorgo

Resumen. El pulgón amarillo, Melanaphis sacchari (Zehntner), se detectó en México en 2013 y se ha dispersado a diversas regiones productoras de sorgo, Sorghum bicolor (L.) Moench, causando daños del 30 al 100%. Se evaluaron en campo insecticidas de diferente modo de acción en dos experimentos que mantuvieron la densidad por abajo del umbral económico establecido de 50 pulgones por hoja. A los 28 días después de la aplicación, imidacloprid sulfoxaflor, flupyradifurone, pymetrozine, spirotetramat, y afidopyropen presentaron las menores densidades de pulgón amarillo. Esta información es relevante, ya que conocer la efectividad de insecticidas con diferente modo de acción permite utilizar los más efectivos y que puedan integrarse con otras medidas que se implementen en el manejo de M. sacchari.