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The sugarcane aphid, Melanaphis sacchari, is a worldwide pest that significantly affects sorghum (Sorghum bicolor (L.) Moench. In the USA this pest can cause up to 100% yield losses, mainly when no action is taken to control this pest. In this study, the potential of three species of Chrysoperla for biological control of M. sacchari was assessed by comparing predation capacity and functional responses of the three species. Individuals of Chrysoperla carnea were collected in a crop of wheat (Triticum aestivum L.) in the State of Guanajuato, México, while C. externa and C. comanche were obtained from a laboratory colony reared on cereal moth, Sitotroga cerealella (Olivier), and from a commercial planting of pecan, Carya illinoensis (Wangenh), respectively. Our results suggested that C. carnea is a good option for an augmentative biological control program against M. sacchari in sorghum because the species had a mean predation capacity of 119.4 nymphs in 24 hours, and a type II functional response; they were able to locate and consume 80% of their prey even at the low prey density of 64. C. carnea had a high coefficient of attack (0.10) and a short handling time (0.10 hour) compared to the other Chrysoperla species. [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]

Although whiteflies Tetraleurodes perseae (Nakahara) (Hemiptera: Aleyrodidae) are considered a secondary pest of avocado crops, their presence and the damages that they cause can decrease crop vigor and affect production. The objective of the present work was to determine the population fluctuation and altitudinal distribution of the T. perseae Nakahara whitefly in avocado trees, as well as to determine the number of possible generations in one year. The study was done in three orchards in Morelos state, located at different altitudes, from February 2014 to April 2015. Samplings were done every 21 days from 10 randomly chosen trees in each orchard. The samples were taken randomly from the middle stratus (1.6 m in height) of each tree; in buds or young leaves for the number of adults and leaves only for nymphs. Additionally, two yellow traps (7 × 14 cm) with glue were placed in each tree for adult samplings. Data were collected regarding vegetative budding, rainfall, relative humidity, and temperature. T. perseae was present in all three sampled orchards, with a greater presence in the lowest orchard, during the whole study period. In the orchard with the lowest altitudinal gradient (1,736 masl), 11 whitefly generations developed; 10 generations developed in the medium gradient orchard (1,934 masl); and 8 generations developed in the highest orchard (2,230 masl). The adults showed a positive relationship with regard to vegetative buds, while the nymphs had a negative relationship with regard to relative humidity. The rest of the parameters showed diverse effects on the species depending on the altitude of the orchard., (© The Authors 2016. Published by Oxford University Press on behalf of Entomological Society of America.)