Densities of insect pests in agricultural communities may be affected by herbicides commonly used for weed management via several routes. First, herbicides may cause direct mortality to insects present both during and immediately following application. Second, herbicides may induce plant defenses that increase resistance to insect herbivores. Third, herbicides may alter the quantity and composition of weed populations, which in turn may change the structure of insect communities found subsequently in the crop. This study was designed to investigate the effects of an array of herbicides on the densities of several major pests found in rice in the southern United States. These pests included the rice water weevil, Lissorhoptrus oryzophilus Kuschel (Coleoptera: Curculionidae), the rice stinkbug, Oebalus pugnax (Fabricius) (Hemiptera: Pentatomidae), and a stemborer complex comprised of three lepidopteran species (Lepidoptera: Crambidae). Insects directly exposed to herbicides experienced high mortality; while those fed leaf material that had been exposed to herbicides did not. Herbicide application did not significantly increase resistance in rice to subsequent herbivore infestation. Results provided modest support for the third hypothesis represented by positive correlations between weed densities and insect pest densities.

The tawny crazy ant, Nylanderia fulva (Mayr) (Hymenoptera: Formicidae), has invaded states of the U.S. including Texas, Louisiana, Mississippi, Alabama, Florida, and Georgia. Native to South America, N. fulva is considered a pest in the U.S. capable of annoying homeowners and farmers, as well as displacing native ant species. As it continues to expand its range, there is a growing need to develop novel management techniques to control the pest and prevent further spread. Current management efforts rely heavily on chemical control, but these methods have not been successful. A review of the biology, taxonomy, ecology, and distribution of N. fulva, including discussion of ecological and economic consequences of this invasive species, is presented. Options for future management are suggested focusing on biological control, including parasitoid flies in the genus Pseudacteon, the microsporidian parasite Myrmecomorba nylanderiae, and a novel polynucleotide virus as potential biological control agents. We suggest further investigation of natural enemies present in the adventive range, as well as foreign exploration undertaken in the native range including Paraguay, Brazil, and Argentina. We conclude that N. fulva may be a suitable candidate for biological control.

The jasmonic acid cascade plays a pivotal role in induced plant resistance to herbivores. There have been a number of investigations into the potential uses of derivatives of this hormone for pest management. Understanding the phenotypic plasticity of plant defense traits interactions in agricultural systems may facilitate the development of novel and improved management practices, which is desirable as management of insects in most agricultural systems is currently heavily reliant on insecticides. The rice water weevil (RWW), Lissorhoptrus oryzophilus Kuschel, is a pest of rice, Oryza sativa, in the southern U.S. and globally. The effects of the jasmonic acid derivative, methyl jasmonate (MJ), on induced defenses to RWW in rice, and the potential costs of MJ-induced resistance to plant growth and fitness, were tested in a series of field and greenhouse trials. It was hypothesized that seed treatments with MJ would reduce densities of larval RWW. A second hypothesis was that MJ seed treatments would alter emergence, biomass accumulation, and yield of rice. The final hypothesis was that induction of plant resistance to the RWW would diminish as the time from seed treatment increased. In order to investigate these hypotheses, RWW densities were determined in greenhouse and field trials. Plant growth was measured in the field by assessing plant emergence, root and shoot biomass, time of heading, and yield (grain mass). Results indicated that MJ seed treatments induced resistance to RWW, although this effect decayed over time. Additionally, there were costs to plant growth and fitness; emergence and heading were delayed and biomass was reduced. Importantly, however, yields on a per-plant were not significantly reduced by MJ treatment. Overall, these results are promising and show the potential for the use of jasmonate elicitors as part of a pest management program in rice.

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The 2018 student debates of the Entomological Society of America were held at the Joint Annual Meeting for the Entomological Societies of America, Canada, and British Columbia in Vancouver, BC. Three unbiased introductory speakers and six debate teams discussed and debated topics under the theme ‘Entomology in the 21st Century: Tackling Insect Invasions, Promoting Advancements in Technology, and Using Effective Science Communication’. This year’s debate topics included: 1) What is the most harmful invasive insect species in the world? 2) How can scientists diffuse the stigma or scare factor surrounding issues that become controversial such as genetically modified organisms, agricultural biotechnological developments, or pesticide chemicals? 3) What new/emerging technologies have the potential to revolutionize entomology (other than Clustered Regularly Interspaced Short Palindromic Repeats)? Introductory speakers and debate teams spent approximately 9 mo preparing their statements and arguments and had the opportunity to share this at the Joint Annual Meeting with an engaged audience.