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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. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

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 weevil's 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. [ABSTRACT FROM AUTHOR]

The psyllid Trioza aguacate Hollis & Martin (Hemiptera: Triozidae) causes deformation of leaves and young shoots of avocado. In recent years, population densities of this pest in avocado orchards have increased. The objectives of this study were to determine seasonal fluctuations of the populations of eggs, nymphs, and adults of T. aguacate, how these fluctuations are related to the incidence of avocado vegetative shoots, temperature and rainfall at 3 different altitudes in Michoacan, Mexico, i.e., 2,130 m, 1,860 m and 1,293 m. In addition, we attempted to determine the spatial distributions of nymphs and adults found on avocado vegetative shoots. We sampled the populations of adult and immature T. aguacate every 20 days from Jan 2012 to Jul 2013. To estimate population densities, 9 trees were selected in each orchard, and the trees were distributed in the form of a cross. From each replicate of trees, 4 shoots were randomly collected, and the eggs and nymphs were counted on them. Adults counts were obtained from yellow traps established at the 4 cardinal points in each tree. During the same period, young vegetative shoots, temperature and rainfall were recorded. The results showed that this psyllid was not present at all in the orchard located at the low altitude level of 1,293 m. The psyllid was present at the medium altitude site from Jan to Jun, and from Dec to Jun at the high altitude site. All of the development stages were most abundant from Mar to May, when avocado vegetative shoots were most abundant in both years. The abundance of eggs and nymphs showed a positive relationship with young vegetative shoots, a negative relationship with rainfall, and the eggs showed a positive relationship with temperature. The incidence of adults was strongly related with spring budding, but not significantly correlated with temperature. Both nymphs and adults had an aggregated spatial distribution. [ABSTRACT FROM AUTHOR]