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The southern corn rootworm, Diabrotica undecimpunctata howardi Barber, is native to the US where it is a pest of peanut, Arachis hypogaea. The banded cucumber beetle, Diabrotica balteata LeConte, is native to the neotropics, but its range has expanded and currently includes most of the US peanut production area. The purpose of this study was to: (i) define seasonal variation in adult rootworm populations in peanut fields, and (ii) determine the effect(s) of proximity to a putative early season host (i.e. corn, Zea mays) and the presence of irrigation on rootworm infestation and pod injury in peanut. Seasonal abundance of adult rootworms in commercial peanut fields in Georgia was monitored in 2021 and 2022 using plant volatile lures attached to yellow sticky traps. Traps were located at 45, 90, and 180 m from the field edge in irrigated and nonirrigated peanut fields with and without a corn border. Two peaks in abundance were observed for both species in each year. Though peak abundance for the two species occurred nearly simultaneously, D. balteata was more abundant than D. u. howardi. Beetle abundance was highest in fields bordered by corn, but presence of irrigation was not as important for D. balteata as it was for D. u. howardi. Pod injury was greater in fields bordered by corn in both years, but there was no difference in pod injury between irrigated and nonirrigated fields. The number of beetles captured and incidence of pod injury within a field did not differ with distance from the field border. [ABSTRACT FROM AUTHOR]

The tobacco thrips, Frankliniella fusca Hinds, is a phytophagous pest and vector of orthotospoviruses in many crops around the world. F. fusca causes direct feeding injury to peanut plants, resulting in leaf chlorosis and curling, and yield loss. Adults and larvae also transmit the economically important tomato spotted wilt orthotospovirus (TSWV) in all peanut market types grown in the U.S. TSWV infection causes spotted wilt disease, a plant disease characterized by chlorosis, stunting, and death. From 1996 to 2006, spotted wilt disease resulted in an estimated U.S.$140 million in annual peanut production losses in the U.S. At present, a thorough documentation of F. fusca 's impacts on the U.S. peanut production system is not available. Here, we describe the morphology, life cycle, and biology of F. fusca and provide images of immature life stages. Feeding injury characteristics and TSWV transmission in peanuts are also discussed. Currently, F. fusca and TSWV are managed in peanut with a combination of tactics, including prophylactic insecticide applications and TSWV-resistant cultivars. However, standardized scouting protocols and economic thresholds for F. fusca are not yet available. Very few biological control agents have been evaluated for use against F. fusca , and few studies have quantified the contributions of native natural enemies. More research into natural enemies' contributions to F. fusca management and the mechanisms underlying TSWV-resistance in peanut could help inform and diversify integrated pest management programs. [ABSTRACT FROM AUTHOR]

BACKGROUND A 2 year field study was conducted at multiple locations to determine whether insecticides or an entomopathogenic nematode, Steinernema carpocapsae Weiser, applied through drip irrigation in sweet potato reduced wireworm damage when compared with the non-treated check and/or insecticides applied conventionally. RESULTS Wireworm damage was low in 2012, and there were no differences in the proportion of roots damaged or the severity of damage between treatments. In 2013, a preplant-incorporated ( PPI) application of chlorpyrifos followed by either bifenthrin, imidacloprid, clothianidin, or oxamyl injected through drip irrigation significantly reduced the proportion of wireworm damage as well as the severity of wireworm damage when compared with the non-treated check. The incidence and severity of wireworm damage in these treatments did not differ significantly from those in the conventional management practice. The PPI application of chlorpyrifos followed by either cyantraniliprole or S. carpocapsae injected through drip irrigation was not significantly different from the non-treated check in the proportion of wireworm damage; however, both treatments reduced the severity of wireworm damage compared with the non-treated check. CONCLUSION Applying insecticides through drip irrigation provides an alternative to conventionally applied insecticides. © 2015 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

Spotted wilt caused by tomato spotted wilt virus (TSWV; family Bunyaviridae; genus Tospovirus) is a serious disease of peanut (Arachis hypogaea L.) in the southeastern United States. Peanut genotypes with field resistance to TSWV are effective in suppressing spotted wilt. All commercially available genotypes with field resistance to TSWV were developed through conventional breeding. As a part of the breeding process, peanut genotypes are regularly screened under field situations. Despite numerous advantages associated with field screening, it is often limited by inconsistent vector (thrips) and TSWV pressure. A greenhouse transmission protocol would aid in thorough screening of selected genotypes and conserve time. In this study, various parameters associated with TSWV transmission, including tobacco thrips, Frankliniella fusca (Hinds) density, mode of inoculation, and plant age, were evaluated. Greater incidences of TSWV infection were obtained with thrips-mediated inoculation when compared with mechanical inoculation. TSWV inoculation with three, five, and 10 thrips resulted in greater incidences of TSWV infection in plants than inoculation with one thrips. However, incidences of TSWV infection did not vary between plants inoculated with three, five, and 10 viruliferous thrips. With both thrips-mediated and mechanical inoculation methods, incidences of TSWV infection in 1-wk-old plants were greater than in 4-wk-old plants. TSWV copy numbers, as determined by qPCR, also decreased with plant age. Results suggest that using at least three thrips per plant and 1- to 2-wk-old plants would maximize TSWV infection in inoculated plants. [ABSTRACT FROM PUBLISHER]

A farmscape study was conducted in commercial sweetpotato (Ipomoea batatas (L.) Lam) fields in Columbus County, NC, in 2010 and 2011 to investigate the effects of the following field conditions: soil drainage class, soil texture, field size, border habitat, land elevation, and the previous year's crop rotation on the incidence of damage caused by Plectris aliena Chapman (Coleoptera: Scarabaeidae) larval feeding. Soil drainage and crop rotation significantly affected the incidence of damage to roots, with well drained soils having a low estimated incidence of damaged roots (0.004) compared with all other drainage classes (0.009-0.011 incidence of damaged roots). Fields with soybeans [Glycine max (L.) Merr] planted the preceding year had the highest incidence of root damage (0.15) compared with all other crops. The effects of border habitats, which were adjacent to grower fields where roots were sampled, showed that as the location of the roots was closer to borders of soybean (planted the year before) or grass fields, the chance of damage to roots decreased. Results indicate that growers can use crop rotation as a management technique and avoid planting sweet-potatoes the year after soybeans to reduce the incidence of P. aliena larval feeding on sweetpotato roots. Environmental conditions such as fields with poor drainage and certain border habitats may be avoided, or selected, by growers to reduce risk of damage to roots by P. aliena. [ABSTRACT FROM AUTHOR]

A three-year evaluation of host crop use by the tobacco budworm [Heliothis virescens (F.)], was conducted from 2001 to 2003 in the central coastal plain of North Carolina. Weekly monitoring of commercial tobacco and non-Bt cotton fields revealed spatial and temporal patterns of host use, and showed that tobacco budworm may be produced in tobacco throughout the growing season. Small plot trials conducted in 2002 and 2003 demonstrated a strong oviposition preference of tobacco budworm for tobacco when located adjacent to plantings of alternate crop hosts. Moths collected in pheromone traps placed up to a quarter mile from primary sources of tobacco budworm production demonstrate sufficient short-range movement by adult insects to facilitate mating of individuals produced in distant cotton and tobacco fields. Results of this study indicate that flue-cured tobacco is an important host of H. virescens in North Carolina. The crop may also serve as a refuge for tobacco budworm from insecticide selection and play a critical role in insecticide resistance management in North Carolina. [ABSTRACT FROM AUTHOR]