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Diaprepes abbreviatus L. (Coleoptera: Curculionidae) is an occasional root pest of plasticulture strawberry in central Florida, USA. There are few chemical insecticide options for larval D. abbreviatus in strawberry. Therefore, we tested soil-applied aqueous Steinernema riobrave Cabanillas, Raulston and Poinar (Rhabditida: Steinernematidae), which is used for D. abbreviatus control in citrus. When S. riobrave was applied (100 infective juveniles per cm2) to the root zones of plants in a D. abbreviatus-affected area of a commercial strawberry field, less than 12% of plants were severely wilted or dead 17 d after treatment, whereas 23% of plants in control plots were wilted or dead. In research plots, peripheral plants and a central plant in each plot were infested with 4 late-instar D. abbreviatus and treated with 1 or 2 applications of S. riobrave (25 infective juveniles per cm2), 1 application of imidacloprid or water (control). Dead S. riobrave-infected D. abbreviatus larvae were recovered from plots to which S. riobrave was applied, but there was no effect of treatment on numbers of live larvae recovered 1, 2, and 3 wk post-application in the peripheral plants. At the end of the experiment, no live D. abbreviatus larvae were recovered from the central plants or the plants proximal to the central plants in plots treated once or twice with S. riobrave. Plant wilting and death due to larval D. abbreviatus root feeding was minimal (averages of 1–1.4 on a 1–5 rating scale) in plants proximal and distal to the central D. abbreviatus-infested plant. Treatment did not affect plant wilting and death rates in the proximal plants, but death of distal plants occurred only in control plots. Our results showed S. riobrave infected and killed late-instar D. abbreviatus in plasticulture Florida strawberry, and further research should be conducted to optimize S. riobrave applications and develop it into a management strategy for D. abbreviatus.

Sugarcane aphid, Melanaphis sacchari (Zehtner), recently emerged as a severe economic pest of sorghum in the USA. This insect was first discovered in the USA feeding on grain sorghum in Texas in 20...

Scirtothrips dorsalis Hood infest strawberry (Fragaria x ananassa Duchesne, Rosaceae) fields from nearby crop fields and surrounding vegetation and cause injury to plants by feeding on young leaf tissues. Greenhouse and field studies were conducted to determine the short-range movement of S. dorsalis to assess the risk of an early S. dorsalis population to spread to adjacent plants. In a greenhouse, 25 potted strawberry plants were arranged in two concentric rows around a central plant, where plants in inner rows were 20 cm, and those in the outer rows were 40 cm from the central plant. In the field, 20 strawberry plants were arranged in two beds (90 cm apart), ten in each bed, and five plants in each row, with plants 30 cm apart. White sticky cards were placed at 60–120 cm from the central plant. Fifty S. dorsalis adults were released on a centrally located plant, and the numbers of S. dorsalis adults and larvae and feeding injury were recorded for 9–17 d on adjacent plants and sticky cards. Results showed that significantly more S. dorsalis adults and larvae remained on the initially infested plant compared to adjacent plants, although few adults were found up to 120 cm on sticky cards. The rate of spread of feeding injury was low with slight bronzing injury (

A number of soybean varieties traditionally bred for resistance to various soybean arthropod pests have been identified as resistant to Megacopta cribraria (F.) (Hemiptera: Plataspidae). However, the mechanisms of host-plant resistance (HPR) in this system are not understood. The goal of this study was to identify the mechanisms of resistance by examining the role of plant volatile organic compounds (VOCs) and free amino acids (FAAs) among 16 soybean varieties. Choice and no-choice cage experiments identified several soybean varieties that demonstrated antixenosis as well as antibiosis. However, resistance varied over time in certain soybean varieties, such as N02-7002 and PI567352B. Mean nymph number from choice experiments had positive correlations with the FAAs asparagine, tryptophan, alanine, phenylanaline, and serine; negative correlation with leucine and threonine. Four plant volatiles, hexanal, 2-pentylfuran, beta-cyclocitral, and cis-9-hexadecenal, were positively correlated with subsequent nymph development, whereas n-hexadecenoic acid was negatively correlated with nymph number only, in adult choice cage experiments. This study contributes to understanding the mechanisms of HPR through associations with plant VOCs and FAAs in relation to M. cribraria development and provides useful knowledge for developing soybean varieties for M. cribraria management.

In order for successful biological pest control using parasitoids, the most suitable naturally available food resources, as well as the fitness of parasitoids feeding on these resources, need to be ascertained. The goal of this study was to improve the understanding of the ecological requirements and consequent fitness of one such parasitoid, Telenomus podisi Ashmead (Hymenoptera: Platygastridae), a predominant stink bug (Heteroptera: Pentatomidae) egg parasitoid native to southeastern USA. We assessed the effects of carbohydrate resources readily available in the wasp's natural habitat on longevity and fecundity of female T. podisi under laboratory conditions. Carbohydrate diets included in the study were buckwheat, Fagopyrum esculentum Moench (Polygonaceae) nectar and honeydew from cowpea aphid, Aphis craccivora Koch (Hemiptera: Aphididae), compared with honey or water controls, which are normally used for laboratory rearing of this species. Eggs of Podisus maculiventris Say (Hemiptera: Pentatomidae) were provided as hosts for oviposition. Honeydew of cowpea aphid proved to be as good a nutrition source as buckwheat nectar, in enhancing wasp longevity and fecundity. We also assessed the importance of honeydew freshness on the biological attributes of T. podisi, as honeydew becomes crystallized or highly viscous on drying up and therefore may pose an issue for uptake by parasitoids. We found that fresh honeydew of the pea aphid, Acyrthosiphon pisum Harris (Hemiptera: Aphididae) significantly enhanced wasp longevity when compared to a diet of 1-day-old honeydew and the fava bean leaf (control). However, fresh honeydew of green peach aphid, Myzus persicae Sulzer (Hemiptera: Aphididae) had the same effect on wasp longevity, fecundity, and proportion of male progeny as radish leaf (control). The potential of certain ubiquitously available food resources, in enhancing biological control of economically damaging pests by parasitoids, is being highlighted in this study; information which could be valuable in similar parasitoid-host systems as well.

To assess overwintering refuge preferences by Telenomus podisi Ashmead, artificial refuges of varying geometries and composition were provided to wasps when exposed to overwintering conditions in an environmental chamber. Field sampling of leaf-litter and tree bark was also used in an effort to determine site preference of overwintering wasps. Under artificial overwintering conditions, wasps preferred to hang inverted while quiescent, regardless of the refuge design, indicating behavior that avoids precipitation or extreme temperature fluctuations during overwintering in field conditions. Wasps preferred refuges with wider gaps between upper and lower surfaces, avoiding spaces that were narrower than their standing height. Parasitoids also preferred settling at least 60 mm from refuge edges. Results suggest that T. podisi has a preference for the type of overwintering refuge that leaf-litter may offer.

The invasive brown marmorated stink bug, Halyomorpha halys, is present in the Piedmont and expanding into the Coastal Plains Regions of the southeastern US. Consequently, this study was conducted to evaluate parasitism and predation of H. halys sentinel egg masses by native parasitoids and predators in woodland habitats and orchard, vineyard, row, and vegetable crops alongside these habitats in Alabama and Georgia in 2017 and 2018. Ten primary parasitoid species, including two new records, and one hyperparasitoid emerged from eggs. Trissolcus japonicus was not detected. Ooencyrtus sp. was the prevalent parasitoid species in vegetables while Telenomus podisi was the predominant species in row crops. Anastatus reduvii, An. mirabilis, Tr. brochymenae, and Tr. euschisti were the prevalent species in woodland and orchard habitats. Trissolcus edessae Fouts occurred primarily in orchards. Trissolcus basalis and Gyron obesum were observed in vegetable habitats. Percentage successful development to adults, sex ratio, and percentage of parasitism per egg mass was highest for Tr. edessae. Predation damage included complete and incomplete chewing, stylet sucking, puncture sucking, and removal of whole eggs from egg masses. Hole and non-stylet sucking damage were discovered. Chewing and piercing-sucking predation constituted the majority of predation in woodlands, plum, blueberry, tomato, pecan, peach, and okra. Mainly chewing predation and egg removal occurred in soybean, cotton, and strawberry. Piercing-sucking predation was common in wine grape and apple. There was no difference between fresh and frozen eggs in the proportion of parasitism and predation both years. In 2017, overall percent parasitism was higher for blueberry compared to other crops except peach and apple. No differences were detected in 2018. Peak parasitism (72.3%) in apple at a site in 2017 represented the highest parasitism rate. Predation was highest in soybean and cotton. Indeed, predation in soybean reached very high levels in 2017 (96.3%) and 2018 (90.3%). In conclusion, native natural enemies parasitize and prey on H. halys egg masses in the southeastern US.

Thrips are early-season pests of cotton and can cause yield and stand losses if not managed. Strip tillage into a winter cover crop, use of a neonicotinoid seed treatment, and foliar insecticide applications are all reliable pest management tactics, but how these methods interact with each other in a thrip-cotton agroecosystem needs to be further understood. A 2-yr field study was conducted to compare thrip counts and thrip-induced plant injury as a function of tillage practice (conventional vs strip tillage with heavy rolled rye), thiamethoxam seed treatment, and foliar insecticide application for managing thrips in cotton. Adult and nymph density, seedling biomass, true leaf formation, stand count, and lint yield were assessed. Results indicate that heavy rolled rye was effective for mitigating thrips on seedling cotton. On conventionally tilled fields, the neonicotinoid seed treatment and a foliar insecticide application were necessary for maximizing yield. Spinetoram was more efficacious than either acephate or cyantraniliprole for management of immature thrips; however, there were no yield effects attributed to foliar insecticide application. These data suggest that growers can mitigate early-season thrips using both cultural and chemically based management tactics.

Tomato, Solanum lycopersicum L. (Solanaceae), is a vegetable commodity which originated in the South American Andes, and is consumed worldwide today. Tomato is attacked by a number of pests causing damage not only to the fruit and stem but also to the root system of the plant. Because of these pests, insecticides are used, overusage of which leads to the development of resistance in pests, and human and environmental health hazards. Fortunately, biological control of tomato pests is a feasible alternative to using chemical insecticides. Biological control tactics including importation, augmentation, and conservation biocontrol are employed worldwide. Biocontrol agents involved in these studies include bacteria, entomopathogenic fungi, yeast, predatory insects, parasitoids, and entomopathogenic nematodes. The results of greenhouse, laboratory, and field-based studies indicate that the potential of biocontrol agents can be increased by understanding the pest–natural enemy interactions. The various biocontrol agents, their potentials, and limitations, as well as suggested management tactics to support biological control in tomato are presented in this chapter.

Megacopta cribraria F. (Hemiptera: Plataspidae) was first reported in the United States near Atlanta, Georgia, in fall 2009 (Suiter et al. 2010, J. Integr. Pest Manag. 1: 1–4) and has since spread throughout the southeastern United States (http:// www.kudzubug.org/distribution_map.cfm). In Asia and the United States, it is commonly associated with its preferred host plant, kudzu, Pueraria montana Lour (Merr.) var. lobata (Willd.) (Fabales: Fabaceae) (Medal et al. 2013, Fla. Entomol. 96: 631–633). Nonetheless, M. cribraria has emerged as a significant pest of soybean, Glycine max (L.) Merrill and may damage a few other legumes in the United States (Eger et al. 2010, Insecta Mundi 0121: 1–11; Hu and Carroll 2012, htpp://agfax.com/2012/05/18/Alabama-soybean-kudzubugs-making-their-move/). In Georgia and South Carolina, yield losses in untreated soybean fields averaged 18% and ranged up to 59.6% (Greene et al. 2012, United Soybean Board, Chesterfield, MO; Seiter et al. 2012, J. Econ. Entomol. 106: 1676–1683). Apart from being odoriferous, crushed nymphs have reportedly caused skin rashes, thereby raising health concerns for workers in soybean fields (Ruberson et al. 2013, Appl Entomol Zool. 48: 3–13). Megacopta cribraria is also viewed as a nuisance pest in fall through spring when adults aggregate on or around homes to overwinter, apparently close to kudzu patches (Eger et al. 2010, Insecta Mundi 0121: 1–11; Ruberson et al. 2013). Little is known about the biology and ecology of M. cribraria in North America. Prominently, we do not understand their behavior and population dynamics when host plants are not available, as in the winter. Knowledge of the overwintering behavior and biology of this species could inform surveillance and management. This study was undertaken to identify overwintering refuge areas preferred by M.

The sugarcane aphid, Melanaphis sacchari (Zehntner), is an economically important invasive insect pest of sorghum, Sorghum bicolor (L.) Moench, production in the southern United States. Studies were conducted to: (1) assess the fecundity of Lysiphlebus testaceipes (Cresson) parasitizing M. sacchari in the greenhouse, and (2) examine the temporal synchrony between L. testaceipes and M. sacchari in the field during 2017 and 2018. Results indicate that after 96 h, the number of M. sacchari increased approximately 90-fold from a single adult in the greenhouse study. The percentage of mummification observed in the greenhouse study was 15.2 ± 3.3%. Of those mummies, L. testaceipes adults emerged from 88.7 ± 4.4%, with 38.6 ± 8.4% of those males. Field observations showed that L. testaceipes appeared in the sentinel fields in late July to August. The percentage of mummies observed in the June- and July-planted plots of 2017, and June-planted plots of 2018 were 4.5 × 10–4 ± 1.5 × 10–4%, 7.4 × 10–4 ± 4.4 × 10–4%, and 4.4 × 10–5 ± 1.7 × 10–5%, respectively. Even though parasitization of M. sacchari by L. testaceipes was observed in both field and greenhouse, the lack of wasps before late July and low rate of parasitization in the field suggest that this species is not well synchronized with M. sacchari populations. Additional natural enemies (e.g., other parasitoids, predators, and entomopathogens) or other adaptations will be necessary before this pest is managed using biological control in Georgia.

Although natural control of pests by their enemies has been recognized for centuries, the use of biological control for insect pest management has only occurred at any significant level within the last century. This chapter covers the historical development and types of biological control as well as the general concepts and methods for how this pest management tool is implemented in cropping systems.

Kudzu bug, Megacopta cribraria Fabricius (Hemiptera: Plataspidae), is an invasive exotic pest of soybeans that has been present in the southeastern United States since 2009 and has been rapidly spreading through soybean-producing states. Their primary reproductive hosts in the United States are soybean, kudzu, pigeon pea, black eye pea, lima bean, pinto bean, wisteria, white sweet clover, white clover, red clover, alfalfa, perennial peanut, and American joint vetch. In soybeans, the kudzu bug feeds on vascular fluids at the stem, petiole, and nodes, causing yield losses of up to 60%. The current management recommendation for this pest includes spraying of pyrethroids such as bifenthrin, but this method is not environmentally friendly, as this negatively impacts beneficial insect populations. Sustainable management tactics, including the development of economic thresholds for insecticide sprays, assessing the spatial and temporal distribution of this pest, manipulating cultivation practices, use of biological control, and host plant resistance, are currently being explored. We present an overview of the ecology of the kudzu bug in soybeans and available management tactics to assist with the management of this potentially devastating pest of soybeans as it spreads westward.