bluuebunny/crossref_metadata_2025 huggingface dataset:
Phyllophaga and Related Species (Coleoptera: Scarabaeidae) Collected in Black-light Traps in Alabama Pastures
Authors: Flanders Kathy L. , DeLamar Zandra D. , Lago Paul K.
Published: September 2017

This study reports the occurrence of the adults of Phyllophaga spp. and other major scarab species in three different geographic regions of Alabama. Thirty-three species of Phyllophaga were found during the trapping study. Five species accounted for 97% of the specimens of Phyllophaga trapped in Marion Junction: P. crinita (Burmeister), P. forbesi (Glasgow), P. hirtiventris (Horn), P. mississippiensis Davis, and P. perlonga Davis. Two species accounted for 55% of the specimens trapped in Camp Hill: P. micans (Knoch) and P. hirticula (Knoch). At Winfield, P. crenulata (Froelich), P. ephilida (Say), P. latifrons LeConte, P. micans, and P. quercus (Knoch) were the most abundant species, making up 49% of the specimens. Of these 11 most abundant species, 5 species were collected in spring (March, April and/or May): P. crenulata, P. hirticula, P. micans, P. mississippiensis, and P. perlonga. Phyllophaga hirtiventris adults were collected in late May–June. Adults of P. crinita were collected in June and early July, and were abundant in each year, suggesting that the species has an annual life cycle in Alabama. Phyllophaga ephilida, P. forbesi, P. forbesi, P. latifrons and P. quercus adults were collected in mid-summer (June, July and/or August). Six species of Phyllophaga found during this study have not been previously reported from Alabama: P. bipartita Horn, P. congrua (LeConte), P. hirtiventris, P. mississippiensis, P. praetermissa (Horn), and P. soror Davis. Cyclocephala lurida Bland, Dyscinetus morator (F.), Euetheola humilis rugiceps (LeConte), and Ligyrus gibbosus gibbosus (DeGeer), other potential pests of grasses, were abundant in the black-light traps. The dung beetle, Onthophagus gazella F., an African species that was purposely introduced into the United States, was abundant at all three sites.
Season-Long Abundance of Generalist Predators in Transgenic versus Nontransgenic Potato Fields2
Authors: Riddick E. W. , Dively G. , Barbosa P.
Published: September 2017

We estimated the effect of deploying Cry3A-transgenic potatoes resistant to the Colorado potato beetle, Leptinotarsa decemlineata (Say), on the season-long relative abundance of naturally-occurring generalist predators. Low inputs of foliar insecticides were used in the transgenic fields to suppress nontarget pests and in the nontransgenic fields to prevent total defoliation of potato plants by L. decemlineata. Dominant plant-foraging heteropteran predators and lady beetles were sampled by sweeping foliage, whereas, ground-foraging carnivorous carabids, ants, and spiders were sampled by trapping in pitfalls. Orius insidiosus (Say) was significantly (P ≤ 0.05) more abundant in transgenic treatment fields than in nontransgenic fields in 1994, but not in 1995. None of the coccinellids (3 taxa) were affected by the treatments in either season. The carnivorous carabids (3 taxa) and ants were not affected by either treatment, but spiders were significantly more abundant in the transgenic treatment fields in 1995. We conclude that the deployment of pure stands of Cry3A-transgenic potatoes, with a minimum input of insecticides to suppress non-target pests, will have no deleterious effects on the populations of generalist predators in the potato ecosystem.
Comparison of Two Computer Techniques and a Visual Technique for the Estimation of Wheat Leaf Consumption by Cereal Leaf Beetle (Coleoptera: Chrysomelidae)
Authors: Sorenson Clyde E. , Ihrig Robert A. , Bradley J. R. , Van Duyn John W. , Herbert D. Ames
Published: September 2017

Three techniques for estimating wheat foliage defoliation by cereal leaf beetle, Oulema melanopus (L.), larvae were evaluated. The techniques were visual estimation, computer estimation with image capture through a flatbed scanner (Lanalyze), and a commercially available video computer image analysis system (CIAS). Both computer-assisted techniques exhibited high levels of repeatability. Both consistently produced errors of less than 3 percent, although each system exhibited different error patterns. The Lanalyze system tended to systematically underestimate actual defoliation of mock leaves, while the CIAS system tended to overestimate actual defoliation. Visual estimators exhibited greater variation among estimates and, on average, greater discrepancies from actual defoliation when compared with the computer assisted techniques. The experience of the observer had a bearing on the accuracy and consistency of visual estimates; more experienced observers had the best accuracy.
Resistance in Maize to Euxesta stigmatias Loew (Diptera: Otitidae)2
Authors: Scully B. T. , Nuessly G. S. , Beiriger R. L.
Published: September 2017

The corn silk fly, Euxesta stigmatias Loew (Diptera: Otitidae), and related otitid species can cause severe crop losses to sweet corn, Zea mays L., grown in tropical and subtropical regions. In Florida, the fall armyworm, Spodoptera frugiperda J.E. Smith (Lepidoptera: Noctuidae), and E. stigmatias are two debilitating insect pests on the sweet corn ear that are considered the most costly and difficult to control. Our purpose was to search for resistance to the corn silk fly in a diverse set of maize germplasm that included sweet, floury, field and popcorn, and to determine if any empirical relationship existed between E. stigmatias damage and S. frugiperda infestation in corn ears. The overall means across two sites, 3 yrs and 16 genotypes was 1.77 for corn silk fly damage, rated on a 0 to 4 prototype scale, and 30.1% for fall armyworm infestation. Clear differences existed between the sweet and popcorn types when compared to the field and floury types. The field and floury corns sustained significantly less damage by the corn silk fly than the sweet and popcorn types (0.91 vs 3.33). Five of these genotypes, CEW-R58, DDSB, GT-RI4, Mp704 and ‘Zapalote Chico 2451’, had both lower corn silk fly damage ratings and lower levels of fall armyworm infestation. Across this broad germplasm base no statistical relationship was identified between corn silk fly damage and fall armyworm infestation, suggesting that each insect species responds independently to different maize genotypes. Husk extension was partly related to reduced S. frugiperda infestation, and tip tightness was partly related to reduced E. stigmatias damage. These results indicate that field corn could possibly serve as source of resistance to the corn silk fly for the improvement of sweet corn.
Prevalence of Viral Diseases of the Fruittree Leafroller, Archips argyrospila (Walker) (Lepidoptera: Tortricidae), in Louisiana
Authors: Goyer Richard A. , Wei Hanxin , Fuxa James R.
Published: September 2017

A nucleopolyhedrovirus (NPV) and a granulovirus (GV) were found infecting field populations of fruittree leafroller, Archips argyrospila (Walker), larvae in Louisiana. Both viruses were recovered from infected larvae at 7 of 8 widely separated sampling sites. Additionally, a small proportion (<5%) of the larvae (maximum 10.2%) had double infections. Overall, infection rates ranged from 0 to 24.4 percent and were statistically correlated with defoliation and host population levels in a positive, density-dependent manner. It appears that though high populations and warm temperatures favor development of a widespread epizootic, the leaf rolls (shelters) protect larvae from contamination at low to moderate population levels. At outbreak larval densities, the rates of viral prevalence approached 25 percent, and the viruses, coupled with other natural control factors may, in time, become effective in population control.
Bollworm (Lepidoptera: Noctuidae) Development and Movement on Bacillus thuringiensis-treated Cotton Leaves
Authors: Ashfaq Muhammad , Young S. Y. , McNew R. W.
Published: September 2017

Larval mortality, survivorship and movement of the bollworm, Helicoverpa zea (Boddie), on and away from Bacillus thuringiensis-treated cotton leaves were investigated in the laboratory. Bacillus thuringiensis (Costar®, Novartis Crop Protection, Inc; Greensboro, NC) was applied to the upper surface of cotton leaves via a spray table in five concentrations, i.e., 0.0 (control), 0.14, 0.29, 0.58, and 1.15 kg/ha. Three-day-old H. zea larvae were released on treated leaves, kept at 30°C, and transferred to artificial diet after 12, 24, and 48 h. Significantly higher numbers of larvae were found on the lower than upper leaf surface after all three transfer times, but the numbers surviving in all treatments were similar to the control. Larval movement from the leaf to cup surface was significantly higher in B. thuringiensis-treated leaves than in the control. The mortality of larvae that were transferred from leaves to diet at 7 d after treatment was significantly higher in all treatments than in the control and highest at the highest rates (0.58 and 1.15 kg/ha). Data on survival of larvae at different locations suggest that for the first 24 h, the increase in the percentage of larvae on the inner cup surface in B. thuringiensis treatments was not due to larvae that had consumed a lethal dose, but an attempt to avoid the B. thuringiensis on the upper leaf surface. Highest larval weight was recorded in the control for all transfer times. The length of the larval period increased with the B. thuringiensis rate at the 12-h transfer. The pupal weight was reduced at the highest B. thuringiensis rates at the 48-h transfer.
Development of Cotesia orobenae Forbes (Hymenoptera: Braconidae) in its Host, Evergestis rimosalis (Guenée) (Lepidoptera: Pyralidae)
Authors: Kok L. T. , Acosta-Martinez J. A.
Published: September 2017

Temperature and host density effects on the development of Cotesia orobenae Forbes (Hymenoptera: Braconidae), and its parasitism of the cross-striped cabbageworm, Evergestis rimosalis (Guenée) (Lepidoptera: Pyralidae), were investigated. Time for adult parasitoid emergence from cocoon masses of C. orobenae maintained at 15, 20, 25, 30 and 35°C and a photoperiod of 15:9 (L: D) was inversely related to temperature. Parasitoid emergence exceeded 86% for all temperatures except that at 35°C. Development of C. orobenae on early-instar hosts was best at 20 and 25°C. Although the shortest developmental time was observed at 35°C, survival of both parasitoid and host was low at this temperature. At 15°C, the parasitoid was not very active, and developmental time was the longest among the temperatures tested. Percent of host larvae parasitized was significantly higher at 20 and 25°C than the other temperatures tested. Females were short-lived and oviposited an average of 118 and 136 eggs at 20 and 25°C, respectively. Females died after 24 h of being placed in the oviposition chamber at 30 and 35°C. At 15°C they lived longer, but did not parasitize host larvae provided. Virgin females produced only male progeny. Mated females produced slightly more female offspring than males. Sex ratios of progeny from females paired with single or multiple males were not different. Percentage parasitization of host larvae between treatments differed for the first day, but not the second day. Fecundity of C. orobenae exposed to five host densities (5, 10, 15, 20, and 25 per parasitoid) showed significant differences in percent parasitization among the treatments. Percentage parasitization was highest with five and 10 hosts per parasitoid. The highest number of parasitoid cocoons recovered per cocoon mass was obtained with 10 hosts. The data indicate that optimal temperature for C. orobenae oviposition, development, and parasitism of its host is between 20 to 25°C.
New Mosquito Collection Records for Southern Georgia
Authors: Smith John P. , Floore Thomas G.
Published: September 2017

Twenty-nine species representing eight genera, numerous new county records and one state record, Mansonia titillans (Walker), were collected in a surveillance project conducted in 20 southern Georgia counties during the summer of 1997. A detailed report of species abundance and diversity is presented. Overall, as sampled by CO2 light traps, Culex quinquefasciatus Say was the most widely distributed species and Aedes vexans (Meigen) was the most abundant species followed closely by Aedes atlanticus Dyer and Knab.
Compounds from Host Fruit Odor Attractive to Adult Plum Curculios (Coleoptera: Curculionidae)
Authors: Prokopy Ronald J. , Phelan P. Larry , Wright Starker E. , Minalga Anthony J. , Barger Richard , Leskey Tracy C.
Published: September 2017

Three release rates of each of 30 compounds identified as components of the odor of unripe host plum or apple fruit were evaluated in field tests in 1999 for attractiveness to adult plum curculios, Conotrachelus nenuphar (Herbst). Compounds were introduced into polyethylene vials and assayed in association with boll weevil traps placed beneath infested apple trees in Ohio and Massachusetts. Results confirmed previously reported attractiveness of limonene and ethyl isovalerate to this insect. In addition, at least six other compounds showed good evidence of attractiveness (benzaldehyde, benzyl alcohol, decanal, E-2-hexenal, geranyl propionate and hexyl acetate), and five other compounds appeared worthy of further evaluation for attractiveness (2-hexanol, 1-pentanol, 2-pentanol, phenylacetaldehyde and 2-propanol). Degree of attractiveness of compounds varied according to release rate.
Enhancement of Nucleopolyhedrovirus Activity in Helicoverpa zea (Boddie) and Pseudoplusia includens (Walker) Larvae with a Fluorescent Brightener
Authors: Young S. Y.
Published: September 2017

The enhancement of nucleopolyhedrovirus (NPV) activity by Tinopal® LPW (Tinopal), a stilbene fluorescent brightener, was compared in Helicoverpa zea (Boddie) and Pseudoplusia includens (Walker) using an on-diet bioassay method. Enhancement of the homologous NPV of each species was compared with three heterologous NPV that have a broad host range. In H. zea, the LC50 of H. zea NPV (HzSNPV) alone was 128 occlusion bodies (OBs)/cup, and the LC50 of it and Heliothis armigera NPV (HaMNPV) did not differ significantly. The activity of both viruses improved 18.6 fold when the OB suspension contained 1.0% Tinopal. The LC50s of Autographa californica NPV (AcMNPV) and Anagrapha falcifera NPV (AfMNPV) without Tinopal in H. zea were greater than that of HzSNPV. However, the increase in activity of AcMNPV and AfMNPV at the highest concentrations of Tinopal was two to three fold greater than the increase in activity of HzSNPV. The LC50 of P. includens NPV (PiSNPV) (856 OBs/cup) alone in P. includens was similar to that of AfMNPV and AcMNPV, and much less than that of HaMNPV (19,947 OBs/cup). The addition of Tinopal to the treatment suspension of all four viruses resulted in significantly lower LC50s at all Tinopal concentrations in P. includens. The highest concentration of Tinopal (1.0%) in the OB suspension lowered the LC50 of PiSNPV by 142.7 and AfMNPV by 89.7 fold. Tinopal in the OB suspension lowered the LC50 of AcMNPV and HaMNPV, but they remained less effective than PiSNPV with Tinopal. HaMNPV at all concentrations of Tinopal was much less active in P. includens than the other viruses with or without Tinopal.
Effect of Cold Storage on Emergence, Longevity, Fertility, and Survival of Cotesia marginiventris (Hymenoptera: Braconidae)2
Authors: Riddick Eric Wellington
Published: September 2017

The effect of short-term cold storage on non-diapausing pupae and adults of Cotesia marginiventris (Cresson) was evaluated for developing protocols for the mass production of this parasitoid. When stored at 10°C, successful emergence of adults from cocoons occurred within 6 d and was not affected by storage time (0 d, 4 d, 12 d, or 20 d). Longevity of males and females was not affected by cold storage, but fewer males and females remained alive per consecutive 8 d interval after emergence at 27°C. A fertility experiment revealed that fewer progeny (F1 cocoons, F1 females) were produced by parental females previously cold-stored as pupae in cocoons for 20 d rather than 4 d. A within-storage adult survival experiment demonstrated that males and females were not affected by any of the storage times (8 d, 16 d, 24 d, 32 d). This survival rate was achieved by removing the adults from the cold at 8 d intervals, placing them at 23 ± 1 °C for ~ 2 h and providing honey. Another fertility experiment revealed that more F1 males, but fewer F1 females, were produced when the parental females (which had been cold-stored as adults) were stored for 32 d rather than for 16 d. This study suggests that adults are more amenable to short-term storage than pupae if the adults are periodically removed for feeding. Nevertheless, cold storage of cocoons (pupae) for 20 d or adults for 32 d can limit the production of female progeny.
Yellow Sticky Traps for Monitoring Males and Two Parasitoids of Oracella acuta (Lobdell) (Homoptera: Pseudococcidae)2
Authors: Sun Jianghua , Clarke Stephen R. , DeBarr Gary L. , Berisford C. Wayne
Published: September 2017

Yellow sticky traps were tested as a method of monitoring populations of males and parasitoids of the mealybug, Oracella acuta (Lobdell). Male O.acuta were captured even when female populations appeared very low. The parasitoids, Allotropa n. sp. and Zarhopalus debarri Sun, were trapped less frequently than O. acuta males, and more traps or longer trapping periods were required to adequately monitor their populations. Significantly more males than females of Z.debarri were trapped, suggesting that yellow traps were more attractive to males, or that males disperse more than females. Yellow sticky traps could be used as part of a biological control program monitoring the establishment and spread of O. acuta and its parasitoids in China.
Evaluation of Glass, Nylon Fabric and Filter Paper as Substrates in Insecticide Bioassays of Cat Fleas (Siphonaptera: Pulicidae)1
Authors: Bossard Robert L. , Broce Alberto B.
Published: September 2017

Four bioassays for use in detecting and measuring insecticide resistance in newly-emerged, unfed adult cat fleas, Ctenocephalides felis (Bouché), were evaluated: horizontal glass, horizontal Nylon 6,6 fabric disk, horizontal cellulose filter paper disk, and vertical cellulose filter paper strip (WHO bioassay). Each bioassay was evaluated using five insecticides: carbaryl, chlorpyrifos, malathion, permethrin, and pyrethrum. LC50s, LC90s, probit line slopes, and slope standard errors were compared. The LC50s on glass were lower than those obtained with the other substrates. This difference was at least an order of magnitude with carbaryl, malathion, permethrin, and pyrethrum. The paper disk and paper strip bioassays produced the highest LC50s and LC90s for fleas treated with carbaryl, malathion, and pyrethrum. With chlorpyrifos and permethrin, the paper strip resulted in the highest LC50s. The nylon disk tended to produce LC50s intermediate between glass and filter paper. On glass, chlorpyrifos generated higher LC50s (2.00 mg[AI]/m2) than permethrin (0.927 mg[AI]/m2) or pyrethrum (0.913 mg[AI]/m2), yet on the paper strip was lower (65 mg[AI]/m2) than permethrin (214 mg[AI]/m2) or pyrethrum (466 mg[AI]/m2). Overall, probit line slopes were highest for glass and WHO. Standard errors of the slope were not significantly different among bioassays. Although nylon disk assay possibly simulates chemical-substrate interactions on carpet, which is a common substrate where cat fleas occur, no single substrate gave acceptably precise probit lines for all chemicals tested, and chemical efficacy depended on the substrate used. Chemical-substrate interactions confound detection of insecticide resistance and chemical efficacy.
Assimilation and Toxicity of Boron in the Argentine Ant (Hymenoptera: Formicidae)
Authors: Klotz John H. , Amrhein Chris , McDaniel Steven , Rust Michael K. , Reierson Donald A.
Published: September 2017

Assimilation of boron by Argentine ants, Linepithema humile (Mayr), fed boric acid—sucrose water solutions was affected by the addition of sorbitol. Concentrations of 10 and 20% sorbitol reduced boron assimilation by 38 and 67%, respectively, thereby significantly reducing the toxicity of the solutions. The effect of solution pH on mortality indicated that the ionized borate molecule was less toxic than the neutral boric acid species. Electron microscopy revealed that ants fed low concentrations of boric acid (0.5%) show gross abnormalities in the microvilli and cells lining the midgut.
Tomatillo Resistance to Colorado Potato Beetle (Coleoptera: Chrysomelidae)
Authors: Kroiss Lori J. , Broz Karen L. , Tong Cindy B. S. , Hutchison W. D.
Published: September 2017

Tomatillo (Physalis ixocarpa Brot ex Hornem) resistance to the Colorado potato beetle, Leptinotarsa decemlineata (Say), was evaluated in the laboratory. In vivo assays confirmed that L. decemlineata larvae fed tomatillo leaves had lower weights and survival than larvae fed potato leaves. Larvae fed potato leaves coated with α-tomatine also had lower weights and survival than controls. Larvae were also fed potato leaves coated with tomatillo leaf extracts. These larvae exhibited lower weights but equal survival compared with the controls. Removal of trichome exudates from tomatillo leaves did not affect the detrimental effects of the leaves on larvae. These results confirm the negative effects of tomatillo leaves and α-tomatine on L. decemlineata larval survival and weight. However, HPLC and mass spectrometry results show that α-tomatine was not present in the tomatillo leaf samples we studied. These results suggest that further research is warranted to isolate compounds for further plant resistance research within tomatillo.
Insect Damage Estimates for ‘Stuart’ Pecan Nutlets from Nut Set to Shell Hardening in Insecticide-Treated and Untreated Trees
Authors: Dutcher James D.
Published: September 2017

Pecan nut loss due to pecan nut casebearer, Acrobasis nuxvorella Neunzig, damage was significantly lower in the chlorpyrifos-treated, ‘Stuart’, pecan trees (0%) than in untreated trees (16%). Percentage loss due to nut drop from all causes between nut set and shell-hardening was significantly lower in the treated (27%) than in the untreated trees (42%). Treated trees had significantly higher average yield (38 kg/tree) than the untreated (29 kg/tree). Nut size was significantly smaller in untreated (156 nuts/kg) than in treated trees (145 nuts/kg). Monitoring the fate of ‘Stuart’ pecan nutlets from nut set to harvest indicated that the number of nuts/cluster at nut set was often positively correlated with kernel weight at harvest, whereas, nut cluster size later in the season was positively correlated with kernel weight at two orchards and negatively correlated with kernel weight in the control treatment at a third orchard. A commercial orchard where pecan nut casebearer, hickory shuckworm, Cydia caryana (Fitch) and nut curculio, Conatrachelus hicoriae Schoof, were controlled with insecticide sprays in the spring had similar total nut drop over the entire season as an orchard where these insects were not controlled. The majority of the pecans that dropped from the trees did not have discernible signs of plant disease, insect feeding damage or insect oviposition.
Evaporation Rates of a Five-Component Attractant for the Rose Chafer (Coleoptera: Scarabaeidae)
Authors: Lingenfelter Eric A. , Williams Roger N. , Haynes LeRoy W. , Fickle Dan S.
Published: September 2017

The attractant developed for the rose chafer, Macrodactylus subspinosus (F.), is composed of pentanoic acid (valeric acid), hexanoic acid, octyl butanoate (octyl butyrate), trans-2-nonen-1-ol and alpha-ionone. Studies were conducted to determine evaporation rates of the five components and evaluate the ability of the attractants to lure beetles at various quantities of attractant over a 3 wk period of adult activity. Pentanoic acid (valeric acid), the compound with the lowest boiling point of the five compounds, was found to decrease from 26% to 7% by gas chromatographic studies. Alpha-ionone, the component with the highest boiling point of the five compounds, increased from 15% to 26%, while the other three compounds increased by 1% to 5%. Field studies demonstrated that lures baited with 5 mL of attractant provided the best results.
Transmission of Tomato Spotted Wilt Virus to Tomato Plants of Different Ages
Authors: Chaisuekul C. , Riley D. G. , Pappu H. R.
Published: September 2017

Thrips (Thysanoptera: Thripidae) and mechanical transmissions of tomato spotted wilt virus (TSWV) to tomato (Lycopersicon esculentum Mill, cv. ‘Sunny Hybrid’) were investigated relative to plant age at the time of inoculation. In 1999, thrips and mechanical transmissions were compared between plants at 7, 14 and 28 d after germination under field exclusion cages. In 2000, thrips transmission was evaluated in plants at 7, 14, 21, 28, 35 and 42 d after germination, and mechanical transmission was evaluated in plants at 14, 21, 28, 35, 42 and 49 d after germination. Subsamples of thrips from flowers of TSWV-infected tomato used in 1999 transmission consisted of 59% Frankliniella occidentalis (Pergande), 34% F. tricici (Fitch), and subsamples of thrips collected from onion used in 2000 transmission consisted of 78% F. occidentalis and 19% F. fusca (Hinds). There was significant yield reduction resulting from early transmission of TSWV in the mechanical transmission test in 2000 (P= 0.008), but not in thrips transmission test in 2000 (P= 0.62). A reduction in the percent of TSWV-damaged fruit in late transmission was significant in the thrips transmission test (P = 0.04) but not in the mechanical transmission test (P= 0.25) in 2000. Lag time from virus transmission to symptom development or to a positive ELISA test was highly correlated to TSWV damaged fruit (P < 0.001 and P < 0.001, respectively) in the mechanical transmission test in 2000. The lag time of a positive ELISA in the thrips transmission test in 2000 correlated with the percentage of TSWV-damaged fruit (P = 0.009). In summary, early infection of TSWV to tomato plants resulted in lower yield and a higher percentage of TSWV-damaged fruits than late infection.
Augmenting Nucleopolyhedrovirus Load in Gypsy Moth (Lepidoptera: Lymantriidae) Populations with Egg Mass Treatments
Authors: Webb R. E. , White G. B. , Thorpe K. W.
Published: September 2017

Previous observations show that gypsy moth, Lymantria dispar L., mortality induced by the fungus Entomophaga maimaiga Humber, Shimazu & Soper is quickly manifested as host population density increases. However, the gypsy moth nucleopolyhedrovirus (LdMNPV) lags behind the rebounding gypsy moth population. In this study, egg masses were contaminated with virus to successfully augment LdMNPV in gypsy moth populations in Virginia. Laboratory bioassays determined the approximate LdMNPV dose to apply to egg masses with and without the addition of the virus enhancer Blankophor BBH to the spray mixture. The highest dose of virus (5.3 × 105 PIBs/mL) tested without Blankophor BBH gave 82.3% mortality. Mortality for this virus dose increased to 91.8% when 1% Blankophor BBH was added. Field studies established that application of virus at an earlier date (04 April) was as efficacious as an application made at a later date (12 April); this study also included a further assessment of the addition of Blankophor BBH to the spray mixture. While application of LdMNPV + Blankophor BBH resulted in faster kill, levels of kill were similar (88.0% for early treatment and 78.8% for later treatment for virus applied alone versus 87.8% for early treatment and 89.1% for later treatment for virus + Blankophor BBH). However, a higher than expected number of cadavers in the LdMNPV + Blankophor BBH treatments had few or no polyhedral inclusion bodies (PIBs). Finally, virus infection resulting from the application of LdMNPV to pupae in June 1998 was compared with infection levels seen after the application of virus to egg masses in April 1999. The April 1999 treatment to egg masses clearly resulted in a higher kill of emerging larvae (=79.3% mortality) compared to the June 1998 treatment to female pupae (with virus incorporated into the egg masses laid by females after adult emergence) (=13.7% mortality). The virus was recovered season-long from larvae collected from populations in the treated plots (but not from control plots), indicating within season spread.
Compatibility of Zineb, Dimethoate and Beauveria bassiana (Balsamo) Vuillemin Against Tarnished Plant Bug (Hemiptera: Miridae)
Authors: Kouassi Mathias , Coderre Daniel , Todorova Silvia I.
Published: September 2017

Experiments were conducted under laboratory and field conditions to assess the effect of the fungicide Zineb (zinc dimethyl-dithiocarbamate) and the insecticide Cygon (dimethoate) on the pathogenicity of the isolate MK 2001 of Beauveria bassiana (Balsamo) Vuillemin, a potential microbial agent for biological control of the tarnished plant bug, Lygus lineolaris (Palisot de Beauvois). The isolate was highly pathogenic to adults yielding an LC50 of 7.2 × 103 conidia/mL at 6 d post treatment and an LT50 of 3.07 d at a concentration of 1 × 108 conidia/mL. Zineb inhibited the in vitro growth of the fungus in Sabouraud's dextrose broth and on Sabouraud's dextrose agar. It had no insecticidal activity against adult L. lineolaris in laboratory bioassays. A field test with caged L. lineolaris adults on lettuce Lactuca sativa L. var. longifolia, at a phenological stage of 50 leaves further demonstrated that Zineb and Dimethoate had no effect on B. bassiana against L. lineolaris. Adult mortality 10 d after application did not differ significantly in treatments with B. bassiana alone from treatments with B. bassiana + Zineb, dimethoate alone, B. bassiana + dimethoate, B. bassiana + Zineb, and B. bassiana + Zineb + dimethoate. No larva was observed in cages treated with B. bassiana alone or in combination with Zineb or dimethoate. On the contrary, 11 larvae/plant were recorded in the untreated cages and 5 larvae/plant in the dimethoate-treated cages.
Influence of Cotton Plant Structures on Heliothine Larval Development and the Production and Infectivity of Occlusion Bodies of Nucleopolyhedrovirus in Larvae
Authors: Ali M. Ibrahim , Young S. Y. , Felton G. W. , Streett D. A.
Published: September 2017

Helicoverpa zea (Boddie) and Heliothis virescens (F.), reared on different cotton structures, were studied for larval growth and development, susceptibility to H. zea nucleopolyhedrovirus (HzNPV), and production of occluded virus (OBs). Larval weight of both species after 10 d of rearing differed with larvae on artificial diet having the highest weight and those on square bracts the lowest weight. In both species, pupal weight and length of pupal developmental period were positively correlated with the larval weight, but length of the larval developmental period was negatively correlated with larval weight. Mortality from virus infection of H. zea and H. virescens larvae on squares, square bracts or flowers did not differ significantly among the structures. In both species, the number of viral OBs produced was greater in larvae fed flowers than those fed other structures and was positively correlated with the weight gained by a healthy larva on that plant structure. The mean LC50 for OBs produced in H. zea or H. virescens larvae on square, square bract or flower did not differ significantly. These results indicate that dietary difference in fruiting structures of cotton plants directly affects H. zea and H. virescens larval growth and development and indirectly affects the production of virus by HzNPV-infected larvae.
Effects of Neem (Azadirachta indica A. Juss) on Trissolcus basalis (Wollaston) (Hymenoptera: Scelionidae), a Parasitoid of Nezara viridula (L.) (Hemiptera: Pentatomidae)
Authors: Abudulai Mumuni , Shepard B. Merle
Published: September 2017

The effects of neem (Azadirachtin indica A. Juss) on Trissolcus basalis (Wollaston), an egg parasitoid of Nezara viridula (L.), were assessed in the laboratory and in cowpea (Vigna unguiculata [L.] Walpers). Treatment of N. viridula eggs with 0.5% (225 ppm azadirachtin) aqueous solution of neem had no effect on parasitization by T. basalis, using both choice and no-choice tests. Parasitoid development and emergence from host eggs treated before or after parasitization also were not affected by neem compared with controls. Additionally, neem did not affect longevity of adult parasitoids from treated eggs or the reproductive activity of females compared with controls. In a field choice test using treated and control eggs, parasitism levels were similar. Also, parasitism of eggs was similar in treated and control cowpea plots. These results suggest that neem may be safe to parasitoids of N. viridula and could be an important component of an integrated pest management program in cowpea.
Antifeedant and Toxic Effects of a Neem (Azadirachta indica A. Juss)-Based Formulation Neemix® Against Nezara viridula (L.) (Hemiptera: Pentatomidae)
Authors: Abudulai Mumuni , Shepard B. M. , Mitchell P. L.
Published: September 2017

The antifeedant activity of Neemix 4.5 EC, a commercial formulation of azadirachtin from the neem tree (Azadirachta indica A. Juss), was tested against adult Nezara viridula (L.) in the laboratory using a cowpea pod-dip method. A toxicity assay was conducted by dipping fourth-instar nymphs. Feeding by adults was significantly reduced in treated pods compared with controls, based on counts of salivary deposits on pod surfaces, inside pod walls and on seeds. The antifeedant effect of azadirachtin was significantly greater on pods treated with 5% aqueous solution than on those treated with 0.5%, indicating that the antifeedant activity was related to concentration. Bugs were initially repelled by Neemix before approaching treated pods to feed. The LC50 for nymphs was 61% (27450 ppm azadirachtin) at 2 d and ranged from 1.8 to 6.2% (810 to 2790 ppm) at 5 d post-treatment, which indicated that neem was slow acting. Sublethal treatment of nymphs disrupted molting and caused morphological defects in adults. Development time to adulthood also was prolonged, and longevity of females was reduced by neem treatments. Azadirachtin may provide an effective component of a comprehensive management program for N. viridula.
Effects of Various Insecticide Residues in Cotton on Gender and Developmental Stage of the Insidious Flower Bug (Hemiptera: Anthocoridae)
Authors: Studebaker Glenn E. , Kring Timothy J.
Published: September 2017

Orius insidiosus (Say) is an important predator of several economic pests in cotton. Laboratory-reared males, females and third-instar nymphs were exposed to field residues of nine insecticides applied to cotton plants. Insects were caged for 24 h and then removed to determine mortality from 0, 1, 2, 3, and 7-day-old insecticide residues. Insecticides and rates (kg ai/ha) tested were spinosad (0.09, 0.199), indoxacarb (0.78, 0.123), imidacloprid (0.027, 0.053), tebufenozide (0.14, 0.28), methoxyfenozide (0.28, 0.84), abamectin (0.01, 0.02), emamectin benzoate (0.005, 0.01), fipronil (0.042, 0.056), and λ-cyhalothrin (0.014, 0.028). Fipronil and λ-cyhalothrin were the most toxic, causing a significant reduction in survival (up to 3-day-old residues). Abamectin and emamectin benzoate caused significant mortality in predators exposed shortly after application, but survival tended to increase as residues aged. Imidacloprid and indoxacarb were intermediate, causing approximately 50% mortality in this insect. Survival was good in all treatments with 7-day-old residues with the exception of λ-cyhalothrin. Males tended to by more sensitive with lower survival than females.
Developmental Stages of Lysiphlebus japonicus Ashmead (Hymenoptera: Aphidiidae), a Bean Aphid Parasitoid
Authors: Ming Gan , Xia Miao Xue , Xiang-Xiong Zhu , De Cheng Ding
Published: September 2017

The developmental stages of a solitary parasitoid, Lysiphlebus japonicus Ashmead, of the black bean aphid, Aphis craccivora Koch, were described by using light and scanning electron microscopy. Lysiphlebus japonicus has four larval instars. The first instar is mandibulate, caudate and has sclerotized spines. Supernumerary neonates are eliminated by powerful mandibles of the first hatched larva. The second instar has degenerative mandibles and is covered with small sclerotized bristles on abdominal segments; the cauda is short and blunt. The third instar is mandibulate; its cuticle is smooth and the caudal segment retrogresses to a short salient. The fourth instar is strong and hymenopteriform; their mandibles are smaller than those of the third instar, and various sensory organs are well developed, especially for the mouthpart.
Evaluation of Degree-Day and Julian-Day Logistic Models in Predicting Cabbage Maggot (Diptera: Anthomyiidae) Emergence and Flight in Upstate New York
Authors: Jyoti J. L. , Shelton A. M. , Barnard J.
Published: September 2017

A 2 yr (1999–2000) study using water-pan traps in the field indicated four generations, including the spring generation, of cabbage maggot adults, Delia radicum (L.), in upstate New York. On average over the 2 yrs, an accumulation of 160.7 ± 8.1 degree-days and 120 ± 3 Julian-days was required for the first adult emergence of flies from overwintered puparia (spring generation). The emergence of 10% of the population required a mean accumulation of 176.6 ± 3.8 degree days and 122.0 + 1.0 Julian days, 25% emergence required 204.2 ± 2.3 degree days and 125.0 ± 1.0 Julian days, 50% emergence required 251.3 ± 3.5 degree-days and 129.3 ± 1.5 Julian days, 75% emergence required 297.6 ± 30.4 degree-days and 132.0 ± 0.0 Julian days, and 95% emergence required 390.9 ± 10.1 degree days and 141.0 ± 3.0 Julian days. From the emergence of the first adult flies, the population required a mean accumulation of 449.2 ± 1.4 degree days to complete the spring emergence. For complete emergence of flies, the F1 generation required a mean accumulation of 508.4 ± 32.9 degree days, the F2 generation required 465.3 ± 21.5 degree days and the F3 generation required 399.1 ± 3.1 degree days. With the help of a degree-days model, it is possible to predict fly emergence in the spring and succeeding generations. This model can help growers minimize insecticide use through better timing of treatments or adjustment of planting dates. In addition, this model will be useful in developing sampling plans and control strategies for immature stages of cabbage maggot.
Film-Coating Seeds with Chlorpyrifos for Germination and Control of Cabbage Maggot (Diptera: Anthomyiidae) on Cabbage Transplants
Authors: Jyoti J. L. , Shelton A. M. , Taylor A. G.
Published: September 2017

The cabbage maggot, Delia radicum (L.), is an important chronic pest of cabbage in the northern U.S. The maggots of this species cause damage to young plants by feeding on roots and stems, resulting in plant stand and yield losses or rendering the crop unmarketable. In New York, the nation's largest producer of cabbage, the most common control practice is to apply a drench or banded spray of chlorpyrifos at transplanting. As an alternative to this practice, we investigated the duration of insecticidal activity of chlorpyrifos film-coated seeds on cabbage transplants. Seeds of the cabbage var. ‘Fresco F-1’ were film-coated with chlorpyrifos at the rates of 0, 9.6, 19.2 or 28.8 g [Al]/kg seed and then examined for phytotoxic effects on germination in the laboratory as well as effectiveness against immature stages of D. radicum under greenhouse and field conditions. Chlorpyrifos film-coated seed treatments did not adversely affect germination in the laboratory tests when plants were grown with peat soil in transplant cell trays and provided significant plant protection against immature stages of cabbage maggot through several weeks after transplanting seedlings with associated soil under greenhouse and field conditions. These results agree with previous European studies showing the potential of seed treatments to reduce damage by D. radicum while at the same time dramatically reducing the amount of insecticide compared with a banded spray or drench application.
Seasonal Abundance, Arrival and Emergence Patterns of Predaceous Hister Beetles (Coleoptera: Histeridae) Associated with Ips Engraver Beetles (Coleoptera: Scolytidae) in Louisiana
Authors: Shepherd William P. , Goyer Richard A.
Published: September 2017

The most common predaceous hister beetles (Coleoptera: Histeridae) found associated with Ips engraver beetles (Coleoptera: Scolytidae) in southern Louisiana were Platysoma attenuata LeConte, P. cylindrica (Paykull), P. parallelum (Say), and Plegaderus transversus (Say). The seasonal abundance of histerids caught in flight traps coincided with Ips spp. activity in the area. Histerid adults were initially caught in sticky traps on Ips-infested loblolly pine logs 1 wk after Ips spp. attacks had begun. As a group, histerids emerged from logs in a bimodal pattern with the first peak occurring during Ips spp. emergence and a second 4 wks later. The abundance of P. parallelum and P. transversus indicates that they likely fed on bark beetles and organisms arriving later in the colonization sequence. Visual orientation appeared to play a role in attraction of histerids to logs colonized by bark beetles. Platysoma attenuata preferred vertically-positioned logs to horizontal logs, while P. parallelum was the opposite. These results suggest that some histerids may be visually attracted to horizontal silhouettes, such as pine trees that have been blown down or felled and often are infested by Ips spp. Other hister beetles may prefer vertical silhouettes, such as standing pines, which tend to be colonized by the southern pine beetle, Dendroctonus frontalis Zimmermann.
Interspecific Variation in Host-Finding Cues of Parasitoids of the Southern Pine Beetle (Coleoptera: Scolytidae)
Authors: Sullivan Brian T. , Dalusky Mark J. , Berisford C. Wayne
Published: September 2017

Experiments were performed with host-associated olfactory attractants of the larval parasitoids of the southern pine beetle, Dendroctonus frontalis Zimmermann, to elucidate both their biological origin and their chemical composition. Sticky-screen traps were erected in an active D. frontalis infestation and baited with parts of D. frontalis-infested loblolly pines (Pinus taeda L.) or their extracts. The diversity of parasitoid species landing on trees infested with larval D. frontalis was substantially greater than that attracted to traps baited with wood and bark taken from similar, infested trees. Females of four parasitoid species, Spathius pallidus (Ashmead), Roptrocerus xylophagorum (Ratzeburg), Dinotiscus dendroctoni (Ashmead), and Eurytoma tomici Ashmead, were attracted to bark infested with D. frontalis larvae. Two of these species, R. xylophagorum and S. pallidus, were attracted to debarked wood from host-infested trees although this tissue was free of hosts and host frass. Spathius pallidus were more attracted to the excised bark (containing D. frontalis larvae and frass) than the debarked wood from D. frontalis-infested pine bolts, while R. xylophagorum were attracted in similar numbers to both materials. When traps were baited with steam/water-distilled extracts of D. frontalis-infested bark, R. xylophagorum strongly preferred extracts from bark containing early-instar larvae over extracts from bark infested with either younger (egg-stage) or older (late-instar larval and pupal) brood. In contrast, S. pallidus responded significantly only to extracts of late larval/pupal bark. Coupled gas chromatograph/mass spectrometer (GC-MS) analyses of the bark extracts revealed that the concentrations of numerous extract constituents correlated positively with trap catch of S. pallidus, but no such relationships were identified for R. xylophagorum. These data provide further evidence that members of the parasitoid complex associated with D. frontalis differ in their strategies for locating trees infested with susceptible hosts.
A Survey of Thrips (Thysanoptera) Species Infesting Cotton Seedlings in Alabama, Arkansas, Georgia, Louisiana, Mississippi, and Tennessee
Authors: Cook Donald R. , Allen Charles T. , Burris Eugene , Freeman Barry L. , Herzog Gary A. , Lentz Gary L. , Leonard B. Roger , Reed Jack T.
Published: September 2017

The common species of thrips that are considered pests of cotton, Gossypium hirsutum (L.), include flower thrips, Frankliniella tritici (Fitch); tobacco thrips, Frankliniella fusca (Hinds); western flower thrips, Frankliniella occidentalis (Pergande); onion thrips, Thrips tabaci (Lindeman); and soybean thrips, Neohydatothrips variabilis (Beach). Thrips feeding on cotton seedlings can inhibit plant growth, reduce plant stand, delay crop maturity, and reduce seed-cotton yield. Surveys were conducted in Alabama, Arkansas, Georgia, Louisiana, Mississippi, and Tennessee to determine the thrips species infesting cotton seedlings during 1996 to 1999. Cotton seedlings were sampled weekly between 7 and 48 days after plant emergence at one to four field sites in each state. Over 12,000 thrips adults were collected using plant washing procedures with 9,005 individuals mounted on slides, and identified to species. The tobacco thrips was the most common species collected in all states, except Georgia, and comprised at least 63% of the thrips adults in all instances, except four. The occurrence of flower thrips and soybean thrips was variable; however, neither species accounted for more than 21% of thrips identified in each state. Western flower thrips accounted for less than 15% of adults collected in all instances except two (28% and 30%) in Louisiana. Also, individual specimens of Thrips nigropilosus Uzel and Anophothrips obscurus Müller were collected in Alabama, and several specimens of Microcephalothrips abdominalis (Crawford) were collected in Arkansas and Louisiana.
Host Preference and Utilization by Melittobia digitata (Hymenoptera: Eulophidae) in Relation to Mating Status
Authors: Deyrup Leif D. , Matthews Robert W.
Published: September 2017

Host preferences of virgin and mated females of Melittobia digitata Dahms were compared in the laboratory using pupae of the flesh fly Neobellieria (=Sarcophaga) bullata (Parker) as hosts. When simultaneously offered two hosts, virgin females used only one of the hosts more often than mated females did. However, the unused second host developed to adulthood significantly less often than did controls, suggesting that the female stung and paralyzed it. Because virgin females lay only a few eggs that always develop into males which utilize very little of the host resource, this behavior seems adaptive in that potential hosts remain available, but developmentally arrested, for later full exploitation by the same female (now mated by her offspring). An additional implication of these results is that females can discriminate one flesh fly host from the other, and choose to avoid oviposition on both.