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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]

Biorational methods (Trichogramma, methoxyfenozide, and spinetoram), conventional control (chlorpyrifos ethyl), and no control were used against pecan nut casebearer, Acrobasis nuxvorella Neuzing, in pecan (Carya illinoinensis (Wangenh) K. Koch), orchards in the Comarca Lagunera region of Coahuila and Durango, Mexico, during the 2016 and 2017 growing seasons. Effects of different management strategies were evaluated on the abundance of A. nuxvorella and damage caused to nuts, as well as abundance, diversity, and rate of parasitism. From April through June both seasons, sexual pheromone traps were used to monitor A. nuxvorella. A sample of 310 panicles from 31 randomly selected trees (10 per tree) was taken to estimate damage by first (May) and second (July) generations of A. nuxvorella each year. The effect of management type on moth abundance and percentage of damage to panicles were analyzed. In 2016 and 2017, management type significantly affected moth abundance. With contrast tests in 2016, significant differences in damage were detected only in the second generation between orchards treated with methoxyfenozide and those treated with spinetoram. In 2017, all management types were statistically similar. In general, spinetoram was most effective in controlling the borer. Parasitism in 2016 was 7.7% for the check and 2.7% in larvae with spinetoram. In 2017, 6.6% of larvae of the check were parasitized, and 2.0% of larvae in the orchard where Trichogramma and methoxyfenozide were used. The most abundant parasitoids were Apanteles epinotiae Viereck (45.4%) and Goniozus nephantidis Muesebeck (31.8%). Parasitoid Macrocentrus instabilis Muesebeck was a new record for the State of Durango, Mexico. [ABSTRACT FROM AUTHOR]