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The leaf-mining microlepidopteran, Macrosaccus morrisella (Fitch) (Lepidoptera: Gracillariidae), has emerged as a new pest of soybean, Glycine max (L.) Merrill (Fabales: Fabaceae), in Canada and the United States, but little is known about its life history traits. Thus, this study was conducted to assess the immature developmental rate of M. morrisella , from egg to adult emergence, on soybean at different temperatures, and the longevity of adults supplied with water and/or honey at different temperatures. The time to 50% emergence of adults was 71.90, 36.33, 24.62, and 17.83 days at 15, 20, 25, and 30 °C, respectively. The lower developmental threshold of M. morrisella was estimated at 8.96 °C, with 425.04 degree-days required for egg-to-adult development. For adult longevity, time to 50% mortality at 25 °C was 15.00, 4.00, and 2.00 days when adults were provided with 25% (v/v) honey–water solution, water, or nothing, respectively. In a follow-up experiment, time to 50% mortality at 25 °C was 24.00, 6.00, 3.00, and 3.00 days when adults were provided with honey and water (offered separately), honey, water, or nothing, respectively, with a synergistic effect when honey and water were offered simultaneously as opposed to honey or water alone. Finally, when fed 25% (v/v) honey–water solution and maintained at 20, 25, and 30 °C, time to 50% mortality of adults was 26.50, 15.00, and 15.00 days. These results inform the understanding of the basic biology of M. morrisella and will help inform the future development of management programs for this insect in soybean. [ABSTRACT FROM AUTHOR]

Pennycress (Thlaspi arvense L.) is an annual plant in temperate regions that often grows as a weed. Pennycress is being domesticated as a new winter cover crop and oilseed crop for incorporation in the Midwest United States corn-soybean rotation, where it could offer economic and environmental benefits. While pennycress is gaining attention as a promising new crop, there remains a significant gap in understanding its interaction with insect communities and agroecosystems. This review compiles available information on insect herbivores (potential pests) and beneficial insects associated with pennycress growing in the wild (natural areas) or as a weed in agricultural areas. The limited knowledge on the response of pennycress to stressors (defoliation, stem injury and stand loss) similar to injury that could be caused by insects is also compiled here. By shedding light on the insects associated with pennycress and how pennycress might respond to injury from insect pests, this review sets the stage for further research and development of integrated pest management programs for insect pests of this new crop. [ABSTRACT FROM AUTHOR]

The soybean gall midge, Resseliella maxima Gagné (Diptera: Cecidomyiidae), is a pest that injures soybeans in the Midwest United States. Little is known about the natural enemies of R. maxima or the potential for biological control. Therefore, we performed a 2-yr survey in Minnesota to examine the predator community associated with R. maxima infestations. We found that Orius insidiosus (Say) (Heteroptera: Anthocoridae) and Pterostichus melanarius (Illiger) (Coleoptera: Carabidae) were the most common foliar- and ground-foraging predators, respectively. Some of the commonly encountered predator species were tested in laboratory predation experiments. Harmonia axyridis (Pallas) (Coleoptera: Coccinellidae) and O. insidiosus represented the foliar-foraging predators tested, and H. axyridis consumed significantly more R. maxima larvae than O. insidiosus. Among the ground-foraging predators, 4 carabids were tested. Poecilus lucublandus (Say) (Coleoptera: Carabidae) and Pt. melanarius consumed significantly more R. maxima larvae than Poecilus chalcites (Say) (Coleoptera: Carabidae) and Bembidion quadrimaculatum oppositum (Say) (Coleoptera: Carabidae). We conclude that Pt. melanarius should receive further attention as a potential biological control agent of R. maxima, due to its high abundance in the soybean fields in this study, temporal overlap with the pest, and high propensity to feed on the pest. [ABSTRACT FROM AUTHOR]