bluuebunny/crossref_metadata_2025 huggingface dataset:
Effects of the Allelochemical, α-tomatine, on the Soybean Looper (Lepidoptera: Noctuidae)
Authors: Gallardo F. , Boethel D. J.
Published: September 2017

To determine the impact of the allelochemical, α-tomatine, on the soybean looper, Pseudoplusia includens (Walker), various concentrations (0.001 to 0.10% wet weight of diet [wwt]) were added to an artificial diet. Neonate larvae were fed on the diet to determine effects on larval weight, developmental time, mortality, and pupal weight. Longer development times were observed at the higher concentrations (0.05 and 0.10% wwt). Larval mortality at 0.10% α–tomatine was signficantly greater (P ≤ 0.05) than all other concentrations. Larval weight was decreased by concentrations of α-tomatine above 0.005% wwt. A linear regression (Y = 217.8 - 2089.5 X, r2 = 0.90) described the relationship between larval growth and α-tomatine concentrations. The effective dose to reduce larval weight by 50% was calculated (ED50 = 0.048% wwt) and then validated in a subsequent experiment. In that study, a significant reduction (P ≤ 0.05) in mean body weight of 10- and 12-day-old larvae was obtained when larvae were fed diet containing the ED50 dose of α-tomatine. Percent growth relative to controls ranged from 56.1 to 52.1% at 6 and 12 days, respectively.
Post Refrigeration Viability of Pteromalus puparum (Hymenoptera: Pteromalidae) Prepupae within Host Chrysalids
Authors: McDonald R. C. , Kok L. T.
Published: September 2017

Pteromalus puparum (L.) prepupae within host Pieris rapae (L.) chrysalids could be stored at 10° C and 80% R. H. for periods of up to 15 months and still produce viable progenies. The mean number of P. puparum adults emerging per chrysalis was not different between four months of cold storage and the non-refrigerated control, but declined progressively with duration of cold storage thereafter.
An Artificial Diet for Cottonwood and Imported Willow Leaf Beetles (Coleoptera: Chrysomelidae) and Comparative Performance on Poplar Foliage2
Authors: Bauer Leah S. , Meerschaert Joann , Forrester O. Thomas
Published: September 2017

An artificial diet was developed for laboratory rearing of the cottonwood leaf beetle, Chrysomela scripta F., and the imported willow leaf beetle, Plagiodera versicolora (Laicharting). To reduce microbial contamination of the media, procedures were developed for separating egg masses and sterilizing egg surfaces. Cottonwood leaf beetle larvae reared from neonate to adult on this artificial diet had greater mortality, took longer to develop, and were smaller than larvae reared on fresh poplar foliage. Adult longevity was similar for both diet-and foliage-reared larvae. Survival and adult fresh weight of imported willow leaf beetle larvae reared on the artificial diet were similar to those of cohorts reared on fresh poplar foliage. However, individuals reared on artificial diet took longer to develop and produced shorter-lived adults than cohorts reared on foliage. Larvae of both species would not eat fresh foliage after being fed on the artificial diet. Adults of both species maintianed on the artificial diet laid few eggs but resumed normal oviposition when fed fresh foliage. This artificial diet proved useful for rearing larvae and maintaining adults during periods when fresh foliage was limited.
A Method for Observing Below-ground Pest-Predator Interactions in Corn Agroecosystems
Authors: Brust Gerald E.
Published: September 2017

A method was developed and evaluated in no-tillage corn fields to investigate the possibility of direct observations of below-ground pest-predator interactions. Rectangular-shaped plexiglass plates were buried parallel to each plant so that roots and a stage of southern corn rootworm (SCR), Diabrotica undecimpunctata howardi Barber, .could be observed. These direct observations through plexiglass demonstrated that five predators were able to remove large numbers of SCR stages; however, only one arthropod (Lasius spp., Formicidae) was an important predator of all SCR stages. Most arthropods successfully attacked only one or two SCR stages. This method enabled detailed observations of below-ground pest-predator interactions and indicated which soil arthropods were important SCR predators. This method elucidated many aspects of SCR-predator activity that had not been possible to observe in previous experiments.
Naturally-Occurring and Synthetic Loline Alkaloid Derivatives: Insect Feeding Behavior Modification and Toxicity2
Authors: Riedell W. E. , Kieckhefer R. E. , Petroski R. J. , Powell R. G.
Published: September 2017

Methanol extracts of tall fescue plants (Festuca arundinacea Schreb.) infected with an endophytic fungus (Acremonium coenophialum Morgan-Jones and Gams) contain loline alkaloids which deter feeding and are toxic to insects. This study was conducted to determine the effect of several naturally-occurring and semi-synthetic loline alkaloid derivatives on insects. The influence of these compounds on the feeding behavior and weight of fall armyworm larvae, Spodoptera frugiperda Smith, and European corn borer larvae, Ostrinia nubilalis Hübner, was evaluated using two-choice, diet-incorporated feeding behavior modification bioassays. Toxicity of these compounds to greenbugs, Schizaphis graminum Rondani, was evaluated and compared with the toxicity of the insecticide nicotine sulfate. Fall armyworm larvae were more susceptible, in terms of feeding behavior modification and reduced weight gain, to specific loline derivatives than European corn borer larvae. N-acetyl loline appeared to show toxic effects, in terms of reduced larval weight in the absence of feeding behavior modification, toward both fall armyworm and European corn borer larvae. Several of the naturally-occurring loline alkaloids, namely N-formyl loline, N-acetyl loline and N-methyl loline, had LC50 values against apterous greenbug adults similar to nicotine sulfate.
The Seasonal Occurrence of the Grape Root Borer, (Lepidoptera: Sesiidae) in the Eastern United States2
Authors: Snow Wendell J. , Johnson D. T. , Meyer J. R.
Published: September 2017

The Grape Root Borer, Vitacea polistiformis (Harris), (Lepidoptera: Sesiidae) was trapped during 1985, 1986, and 1987 in seven, nine, and 13 eastern states, respectively, with pure (E,Z)-2,13 octadecadienyl acetate or a 99:1 blend of (E,Z)-2,13 octadecadienyl acetate and (Z,Z)-3,13 Octadecadienyl acetate. The length of adult activity periods ranged from six months in Florida to two or three months in Pennsylvania, Maryland, New Jersey, and Ohio. Bimodal peaks of activity occurred most commonly in the South, and single peaks were most common in the North. Activity usually began in all states (except Central Florida) in June or early July, with principal activity occurring in August in the extreme South, in late July in the central states, and about the first of July in the northern states. In Central Florida, flight began in late July with principal activity in September. Twelve other species of sesiid moths were also collected with the sex attractant, including large numbers of Melittia cucurbitae (Harris), Paranthrene simulans (Grote), and Paranthrene asilipennis (Boisduval).
Comparative Analysis of Two Rearing Procedures for Diamondback Moth (Lepidoptera: Plutellidae)
Authors: Shelton A. M. , Cooley R. J. , Kroening M. K. , Wilsey W. T. , Eigenbrode S. D.
Published: September 2017

Rape seedlings, Brassica napus L., and a wheat germ-based artificial diet were compared as media for rearing diamondback moth (DBM), Plutella xylostella (L.), for six generations. Mean pupal weight and total number of eggs laid per female were always greater when larvae were reared on artificial diet; however, percentage of eggs hatching was usually greater and development time usually shorter when larvae were reared on rape seedlings. High larval survivorship (>70%) could be obtained on either media. Larvae which were reared on artificial diet were consistently more susceptible to the insecticides methomyl and permethrin, indicating potential problems in using artificial diet for insecticide studies. When larvae were reared on either medium for six generations and then transferred to cabbage, larval survivorship was nearly equal, indicating that either method could be used for artificially incoculating plants for host plant resistance studies. Although it was easier and cheaper to rear DBM on artificial diet, recommendations for using one rearing method over the other must be based on the ultimate use of the colony.
Toxicity and Repellency of Chenopodium Oil To Four Species of Stored-Product Insects2
Authors: Su Helen C. F.
Published: September 2017

Chenopodium oil, an essential oil of Chenopodium ambrosioides L., was evaluated for its toxicity and repellency to adults of Callosobruchus machulatus (F.), Sitophilus oryzae (L.), Lasioderma serricorne (F.), and Tribolium confusum Jacquelin du Val. Topically applied, the oil was highly toxic to C. maculatus (100% mortality at 40 μg/insect) and L. serricorne (92.5% mortality at 50 μg/insect), moderately toxic to S. oryzae (52.5% mortality at 50 μg/insect), and only slightly toxic to T. confusum at 50 μg/insect. When applied to the surface of wheat, the oil was highly repellent to S. oryzae. When applied to wheat or black-eyed peas, the oil reduced infestations of S. oryzae and C. maculatus at dosages of 2000 and 1000 ppm, respectively.
Seasonal Responses of Corn Rootworm Beetles (Coleoptera: Chrysomelidae) to Non-pheromonal Attractants2
Authors: Lance D. R. , Elliott N. C.
Published: September 2017

Western, Diabrotica virgifera virgifera LeConte, and northern, D. barberi Smith and Lawrence, corn rootworm beetles were captured in a cornfield at traps baited with volatile attractants during three portions of the season. In dent-stage maize (3–4 wk past flowering), traps baited with eugenol captured large numbers of D. barberi, whereas traps baited with p-methoxycinnamonitrile (p-MCN) or estragole captured large numbers of D. v. virgifera. The attactants were less effective in two earlier trials when maize was in the whorl or silking stage. Despite seasonal differences, baits containing p-MCN attracted significant numbers of D. v. virgifera during all three trials. Attractants were also tested simultaneously in plots of corn that were planted on one of three different dates. With D. v. virgifera, attractants were relatively less effective in plots of maize that were silking than in plots of whorl-stage or dough-stage maize; with D. barberi, attractants were effective only in plots of whorl-stage maize. Changes in phenology of maize appear to be at least partially responsible for seasonal variation in attractancy of non-pheromonal lures for rootworm beetles. This seasonal variation will affect the use of non-pheromonal attractants in management applications.
In vivo Production of a Nuclear Polyhedrosis Virus Utilizing Tobacco Budworm and a Multicellular Larval Rearing Container2
Authors: Bell M. R.
Published: September 2017

The effects of viral inoculum and incubation period on virus yield in a method of in vivo production of the multicapsid nuclear polyhedrosis virus of Heliothis armigera (Hübner) were examined utilizing Heliothis virescens larvae reared in multicellular containers. Trays of diet were surface contaminated with virus levels ranging from 54 to 2708 polyhedral inclusion bodies (PIB) per mm2 of diet at 7 days after egg infestation. The virus was harvested either at 6 or 7 days after treatment. Within the ranges of this study, the greatest quantity virus was obtained when the diet was inoculated with the 54 PIB level, and the virus was harvested at 7 days. This combination resulted in an average production of 2919 × 109 PIB per tray, with 5.7 × 109 PIB per larvae and 523 collectable larvae per tray. It also represented an increase in polyhedra of 2.43 × 105× compared to the inoculum. The costs of the production were estimated based on prevailing wages and current costs of materials.
Temperature-dependent Development of Immature Carcinops pumilio (Coleoptera: Histeridae), a Predator of Musca domestica (Diptera: Muscidae)2
Authors: Fletcher M. G. , Axtell R. C. , Stinner R. E. , Wilhoit L. R.
Published: September 2017

The development rates of the immature stages of Carcinops pumilio (Erichson), a predator on eggs and first instar larvae of the house fly, Musca domestica L. were determined at six constant temperatures: 17.5, 19.5, 25.5, 30.0, 32.5 and 35.0°C. At the six temperatures, respectively, the median development times (days) were for eggs: 25.5, 14.3, 7.4, 3.8, 3.5 and 3.5; for larvae 37.7, 20.9, 9.4, 6.0, 6.0 and 6.0; and for pupae 42.8, 33.6, 17.0, 9.7, 7.4 and 8.3. Maximum development rates for all stages were at 32.5°C. The percentage of survival at the six temperatures, respectively, for larvae were 66, 92, 98, 100, 93 and 93, and for pupae were 56, 86, 90, 100, 93 and 78. The parameters for the Sharpe and DeMichele (1977) temperature-dependent development model and the Stinner et al. (1975) distribution of development model were estimated from the constant temperature data and validated under a variable temperature cycle.
Diurnal Abundance and Spatial Distribution of Armyworm, (Lepidoptera: Noctuidae) in No-till Corn
Authors: Laub Curtis A. , Luna John M.
Published: September 2017

Armyworm, Pseudaletia unipuncta (Haworth), spatial and diurnal abundance in no-till corn was sampled at six-h intervals (at 0200,0800, 1400, and 2000) during three 24 h periods. During the early growth stages of corn, armyworm density on corn plants was higher during nighttime, and differed significantly between 0200 and 1400 hours. The number of armyworm feeding on leaf edges of the early growth stages of corn was significantly higher at 0200 than during any other time, and the proportion of total larvae on corn plants that were on leaf edges was significantly higher at 0200 than during the daytime. Daytime foliage sampling will underestimate the true populations of armyworm feeding on foliage by 1.8 to 31 fold, depending on the time and thoroughness of the sampling program.
Effect of Food and Mating on Longevity and Egg Production in the Green June Beetle (Coleoptera: Scarabaeidae)
Authors: Domek John M. , Johnson Donn T.
Published: September 2017

A laboratory rearing experiment was conducted to determine the effect of food intake and mating on longevity and egg production of the female adult green June beetle, Cotinis nitida (L.). A positive relationship existed between the number of eggs laid per beetle and beetle longevity (r = 0.37; P < 0.0001), where apple-fed beetles laid 2.2 eggs per day during a lifespan of 23.0 days and the water-fed beetles laid 1.87 eggs per day during a significantly shorter lifespan of 14.8 days (P < 0.0001). After mean adjustments for the effects of beetle longevity (by the LSMEANS procedure), the apple-fed beetles laid an average of 50.8 eggs which was significantly higher than the 26.9 eggs laid by the water-fed beetles (P < 0.0002). The number of matings had no effect on the numbers of eggs produced nor on beetle longevity. The treatment effects on percentage egg hatch by mating and feeding were insignificant. However, the effect of mating on the percentage of egg hatch differed depending on feeding. These differences were presumed to be due to soil differences between egg rearing containers and not to the effects of mating or feeding. These results suggest that feeding beetles live longer and produce more offspring than beetles that do not feed.
Bioassay for Screening Plant Accessions for Resistance to Fall Armyworm (Lepidoptera: Noctuidae) Using Artificial Diets
Authors: Diawara M. M. , Wiseman B. R. , Isenhour D. J.
Published: September 2017

Laboratory bioassays demonstrated that formulation of artificial insect diet influenced the expression of antibiosis to fall armyworm (FAW), Spodoptera frugiperda (J. E. Smith), in grain sorghum, Sorghum bicolor (L.) Moench. Larvae of FAW were reared on a diet formulated with pinto bean and a diet formulated with no pinto bean, both supplemented with dried milk stage florets of resistant and susceptible sorghum genotypes. The sorghum lines showed a significantly higher antibiosis to FAW when mixed in the diet formulated with no pinto bean than when mixed in the diet containing the bean. Larvae that were fed the no-bean diet supplemented with resistant sorghum genotypes weighed one-half to one-third less, required longer to pupate, and resulted in lighter pupae than larvae reared on mixtures containing the bean. The results obtained when the larvae were reared on the bean diet were significantly correlated (P = 0.0001, r > 0.80, n = 18) with those recorded when the no-bean diet was used for the FAW variables measured. Because a higher expression of antibiosis is obtained with the no-bean diet, this formulation should be recommended for bioassays designed to study lines with low levels of resistance to insects or to screen plant introductions in which the level of resistance is not known.
Effectiveness of Three Residual Insecticide Formulations To Control Red Flour Beetles (Coleoptera: Tenebrionidae) On Painted and Unpainted Steel2
Authors: Claborn D. M. , Tetrault G. E. , Arthur F. H.
Published: September 2017

Three insecticides were tested for efficacy against adult red flour beetles on painted and unpainted steel plates. Microencapsulated formulations of chlorpyrifos and diazinon provided 100% control for 47 weeks on both painted and unpainted surfaces. A lacquer-based formulation of chlorpyrifos was not as effective and could have been affected by paint. These findings have importance in the control of stored product insect pests on painted metal surfaces, including the decks of naval vessels.
A Comparision of Reproduction and Longevity in Pyrethroid-Resistant and Susceptible German Cockroach (Blattodea: Blattellidae) Field-Collected Strains
Authors: Ross Mary H.
Published: September 2017

Life histories of five field-collected strains of the German cockroach, Blattella germanica, were studied. Three were highly resistant to pyrethrins and allethrin; two were susceptible. Life history parameters of the susceptible strains and one of the resistant strains were closely similar. Two of the three resistant strains differed from the susceptible strains and from the third resistant strain. Differences from the latter strains included a longer interval between hatch of successive egg cases, fewer viable (hatched) egg cases per female, a more uneven pattern of maturation among nymphs from individual oothecae (egg cases), fewer adult progeny per egg case, and lower total numbers of adult progeny per life span of females. No significant difference occurred between the two resistant strains in any of the foregoing characteristics.
Synergistic Effects of Oak Volatiles with Ethanol in the Capture of Saprophagous Wood Borers2
Authors: Dunn James P. , Potter Daniel A.
Published: September 2017

We tested the response of wood and phloem boring Coleoptera to traps baited with ethanol alone, and to ethanol baits augmented with oak logs. The logs provided a source of natural oak volatiles, and we hypothesized that these volatiles would increase attraction of borers to ethanol. Ethanol baited traps augmented with oak logs attracted 2.3 times more cerambycid adults than ethanol alone, and 4.9 times more cerambycids than logs alone. Logs alone were not attractive to Scolytidae, nor did they enhance attractiveness of ethanol alone to scolytids. Although many saprophagous wood and phloem feeding Coleoptera are attracted to ethanol, these results suggest that for some groups of borers, other tree emitted volatiles may also aid host location.
Comparison of Diets of Two Fire Ant Species (Hymenoptera: Formicidae): Solid and Liquid Components
Authors: Tennant Leeanne E. , Porter Sanford D.
Published: September 2017

Diets of the red imported fire ant, Solenopsis invicta Buren, and the native fire ant, Solenopsis geminata [F.], were studied in adjacent field colonies in south central Texas. A comparison of solid food diets of the two species revealed a 59% overlap of identifiable arthropods and other solid food matter. The major difference was that S. geminata collected eight times more seeds than did S. invicta. Both species collected liquid food much more frequently than solid food; in fact, an average of 70–80% of successful foragers returned with liquid. Rates of liquid collection were approximately 40% higher for S. invicta than for S. geminata. Foraging rates fluctuated with season but the percent of successful foragers returning with liquid remained relatively constant. Plants and honeydew producing homopterans are the most probable sources of this liquid based on sugar and amino acid analyses of S. invicta foragers. Use of liquid carbohydrate energy sources helps explain how fire ant colonies can collect sufficient food to sustain extremely dense field populations.
Susceptibility of Prepupae of the Colorado Potato Beetle (Coleoptera: Chrysomelidae) to Entomopathogenic Nematodes (Rhabditida: Steinernematidae, Heterorhabditidae)
Authors: Cantelo William W. , Nickle William R.
Published: September 2017

This research investigated the ability of five species or strains of parasitic nematodes to control the Colorado potato beetle, Leptinotarsa decemlineata (Say), when beetle prepupae were released on potting soil containing the nematodes. The nematodes tested were: Steinernema carpocapsae Weiser (All strain); S. carpocapsae (Mexican strain); S. feltiae (= bibionis) (Filipjev) (strain #27); S. feltiae (strain #980) and Heterorhabditis bacteriophora Poinar. Six dosage levels ranging from 10.3 to 329.2 nematodes/cm2, in addition to the water-only controls, were used in these laboratory tests. Each dosage-strain combination was replicated four times with 20 prepupae exposed to each individual treatment. The five strains demonstrated 100% kill at 164.6 nematodes/cm2. Except for the Mexican strain of S. carpocapsae, every strain produced over 98% mortality at 82.3 nematodes/cm2. Dosage response regression equations were calculated for each strain. Although field applications probably would require higher rates to obtain the same mortality, the use of parasitic nematodes has potential for suppressing Colorado potato beetle populations. The cost or dosage rate of nematodes may have to be reduced before the control costs would be acceptable to a grower.
Potato Leafhopper (Homoptera: Cicadellidae) Utilization of Alfalfa as a Host: The Role of Non-Host Stimuli
Authors: Smith Lane M. , Lamp William O. , Armbrust Edward J.
Published: September 2017

The effect of non-host crabgrass, Digitaria sanguinalis (L.) Scop., on potato leafhopper, Empoasca fabae (Harris) (Homoptera: Cicadellidae), utilization of alfalfa, Medicago sativa L., as host was investigated in binary choice experiments that measured oviposition and residency preference of adults. Leafhoppers preferred to oviposit and reside on pure alfalfa over alfalfa mixed with crabgrass. Successive experiments in which crabgrass was presented to leafhoppers with fewer sensory cures (i.e. tactile, gustatory, visual, olfactory) demonstrated that olfactory cues alone from crabgrass may explain the lower preference equally as well as any combination of other cues. Thus, volatile chemicals from crabgrass reduced acceptability of alfalfa for the potato leafhopper, although visual stimuli are not completely excluded. Additional experiments showed that leafhopper density, lighting, and alfalfa density all may influence leafhopper host utilization in laboratory experiments.
Respiration and Behavior of a Sugarcane Grub, Ligyrus Subtropicus (Coleoptera: Scarabaeidae) Under Flooded Conditions
Authors: Cherry R. H. , Porter P. S.
Published: September 2017

The sugarcane grub, Ligyrus subtropicus (Blatchley) encounters both natural field flooding and controlled field flooding by Florida sugarcane growers. Third instar larvae (grubs) of L. subtropicus were tested in various flood tests. After a five day (120 h) simulated flood, 68% of grubs survived at 18° C versus 0% at 28° C. Respiration as indicated by CO2 production was significantly higher in grubs at 28° C in both flooded and unflooded treatments than in grubs at 18°C under similar conditions. These data indicate that grubs drown faster at higher temperatures at least partly due to increased respiration. In behavior tests conducted at water temperatures of ca. 24° - 25°C, grub populations moved upward in response to flooded conditions including 21.7% of the grubs which emerged from the soil to settle on the soil surface. Grubs became sluggish after 2 h underwater. Within 24 h underwater, all grubs were comatose (non-responsive to probing) and remained in this condition until death.
Effects of Abamectin on Peachtree Borers in the Laboratory and in Peach Orchards (Lepidoptera: Sesiidae)2
Authors: Yonce C. E. , Taylor J. L.
Published: September 2017

Abamectin was effective in reducing egg hatch, larval survival, adult mating behavior and oviposition of the lesser peachtree borer, Synanthedon pictipes (Grote and Robinson) LPTB, and egg hatch and larval survival of the peachtree borer, Synanthedon exitisoa (Say) PTB, in the laboratory at rates of 10 and 20 ppm. Subsequently, tests in peach orchards with comparable rates of abamectin were effective in reducing PTB populations in Peach and Taylor counties, Georgia. Although abamectin was less effective than chlorpyrifos (standard recommendation) for PTB control, it warrants consideration as an alternative for control because it is a natural product derivative and probably poses little threat to the environment.
Incidence of Dicymolomia julianalis (Lepidoptera: Pyralidae) on Musk Thistle in Tennessee
Authors: Powell Steve D. , Grant Jerome F. , Lambdin Paris L.
Published: September 2017

The incidence of the pyralid Dicymolomia julianalis (Walker) on musk thistle, Carduus thoermeri (Weinmann), was monitored at 15 sites in eastern and middle Tennessee during 1989 and 1990. Seed heads infested by larvae and/or pupae of D. julianalis were recovered from all sites. During 1990, infestation levels of mature seed heads at each site on each sampling date ranged from 0 to 30.9%. Of 2,570 seed heads collected from all sites during 1990, 14.2% (365) was infested by D. julianalis. Larvae of D. julianalis were observed to feed on seeds of musk thistle, and a mature seed head that had been infested by as few as one larva did not release seeds. However, the interactive association of D. julianalis and musk thistle is unclear because of its reported diversity of food types and habitats. Our results suggest that seed production and proliferation of musk thistle were apparently reduced by D. julianalis.
Control of Edaphic Populations of Woolly Apple Aphid using Entomopathogenic Nematodes and a Systemic Aphicide
Authors: Brown M. W. , Jaegers J. J. , Pye A. E. , Schmitt J. J.
Published: September 2017

The effects of an entomopathogenic nematode, Steinernema carpocapsae (Weiser), and an experimental systemic aphicide, RH-7988, on edaphic populations of the woolly apple aphid, Eriosoma lanigerum (Hausmann), were investigated. Laboratory experiments showed that presence of the nematode in a culture of woolly apple aphids increased the mortality rate. Nematodes were found inside the body cavity of several aphids with entry possibly being through the anus via a droplet of honeydew. Field trials in an unsprayed six-year-old and four-year-old apple orchard tested the efficacy of broadcast spray and topdressing applications, respectively, of nematodes at a rate of 376,600 nematodes/m2. The broadcast spray trees had fewer aphid colonies on roots than the untreated controls (P = 0.10), but the topdressing treatment had no effect. The systemic aphicide, RH-7988, was tested in a two-year-old apple orchard. Two rates of foliar and soil application were tested, with all treatments significantly reducing arboreal woolly apple aphid populations. Edaphic populations were also significantly reduced one month after treatment, but no difference was found four months after treatment. Both control methods show promise as potential management options for edaphic woolly apple aphid populations.
Evaluation of Pheromone Dispensers for Use in Gypsy Moth Detection (Lepidoptera: Lymantriidae)2
Authors: Leonhardt B. A. , Mastro V. C. , DeVilbiss E. D.
Published: September 2017

Seven controlled-release dispenser formulations containing 500 μg of gypsy moth pheromone (+)-disparlure, were compared in laboratory and field tests. Pheromone release rates, residual pheromone contents, and male moth captures in traps baited with the dispensers were compared following pre-aging of the dispensers in a greenhouse at 35 °C for 0, 4, 12, and 16 wk. The laminate dispenser, now used in USDA detection traps, became less attractive over time as its pheromone release rate and content dropped below the threshold values previously reported as necessary for effective attraction. A polyvinyl chloride coated twine dispenser produced high male moth captures and gave release rates and residual contents above these thresholds (30 ng/h release rate and 100 μg content) at all aging periods. The tube-A dispenser was the most effective of the new commercially prepared formulations, followed by the membrane and tube-B whose male moth captures and release rates tended to increase with aging time. The capsule and film dispensers were the least effective of the formulations tested.
Efficacy of Aerially-Applied Gypchek against Gypsy Moth (Lepidoptera: Lymantriidae) in the Appalachian Highlands2
Authors: Podgwaite John D. , Reardon Richard C. , Walton Gerald S. , Witcosky Jeffrey
Published: September 2017

Gypsy moth, Lymantria dispar L., populations in six northern Virginia plots were aerially treated with the nucleopolyhedrosis virus product, Gypchek. Two applications of an aqueous Orzan LS-Pro Mo-Rhoplex B60A tank mix, each at 18.7 liters and 1.25 × 1012 polyhedral inclusion bodies per ha, reduced larvae by more than 92% and egg masses by more than 94% in all but one of the treated plots. Defoliation averaged 22% in Gypchek-treated plots compared to 67% in control plots.
Noctuidonema guyanense (Nematoda: Aphelenchoididae): Population Profiles on Male and Female Fall Armyworm Moths2
Authors: Rogers C. E. , Marti O. G.
Published: September 2017

The distribution of Noctuidonema guyanense Remillet and Silvain (Nematoda: Aphelenchoididae) populations on wild female, laboratory-reared female, and wild male moths of Spodoptera frugiperda (J. E. Smith) (Lepidoptera: Noctuidae) was determined. Populations of all life stages of N. guyanense were aggregated (P < 0.05) on abdominal segments 7–10 of wild female and moderately infested (<100 nematodes), laboratory-reared female moths. Nematodes also aggregated on abdominal segments 7–10 on heavily infested (>300 nematodes), laboratory-reared female moths, but larger populations of all mobile life stages migrated from posterior to anterior abdominal segments of a host. On wild male moths, N. guyanense populations tended to disperse along the host's abdomen, with significant aggregates of eggs and neonates on abdominal segments 8–10 and smaller aggregates of adults and juveniles on abdominal segments 1–2. Nematodes avoided colonization of the head of nearly all hosts of either sex.
Functional Response of Anisopteromalus calandrae (Hymenoptera: Pteromalidae): Influence of Host Numbers Versus Host Density
Authors: Smith Lincoln , Press John W.
Published: September 2017

The functional response of Anisopteromalus calandrae (Howard) was measured on rice weevil, Sitophilus oryzae (L.) (Coleoptera: Curculionidae), in wheat at 30° C. Four female parasitoids, with males, were allowed to oviposit during their lifespan on 166 to 678 weevils per container. The data were fit by Rogers' (1972) random parasitoid model with rate of parasite search a = 0.32 lifespan−1 and handling time Th= 0.0027 lifespan. Volume of grain, in the range of 0.19 to 3.1 l wheat, had no effect on number of hosts parasitized when host numbers were held constant at 222, 398, and 572 weevils per container. Therefore, it may be more appropriate to consider numbers of hosts present rather than host density when studying functional response within a patch of uniformly distributed hosts.
Effects of Inherited Sterility and Insect Resistant Dent-Corn Silks on Helicoverpa zea (Lepidoptera: Noctuidae) Development
Authors: Carpenter J. E. , Wiseman B. R.
Published: September 2017

Male and female corn earworm, Helicoverpa zea (Boddie), adults were exposed to a substerilizing dose (10 krads) of gamma radiation after which their progeny were reared on a meridic diet containing selected concentrations of dry silk collected from resistant dent corn genotypes. Significant interactions were observed between the developmental time of progeny from irradiated females and progeny from normal parents and meridic diets with increasing degrees of resistance. A significant interaction also was observed between the mean larval weights of normal and substerile larvae and diets with increasing degrees of resistance. The 9-d weight of normal larvae was significantly higher than the weight of substerile larvae at the lowest degree of resistance, but differences between the weight of normal and substerile larvae at the highest degree of resistance were not significant. Larvae from irradiated male by normal female crosses were equally competitive with normal larvae for all measured parameters. Data from this study suggest that plant resistance and inherited sterility would be compatible control strategies for the management of H. zea populations.
Susceptibility of Crape Myrtle, Lagerstroemia indica L., to the Crapemyrtle Aphid (Homoptera: Aphididae) in North Florida
Authors: Mizell Russell F. , Knox Gary W.
Published: September 2017

Thirty seven cultivars of the crape myrtle, Lagerstroemia spp., were evaluated in a two year study in north Florida for susceptibility to the crapemyrtle aphid, Tinocallis kahawaluokalani (Kirkaldy). Numbers of crapemyrtle aphids per leaf were monitored each week from June to October in 1990 and 1991. Peak aphid numbers occurred in both years during the last week in July. Cultivars with L. fauriei parentage, and cultivars that are susceptible to or those with resistance to powdery mildew had significantly higher aphids per leaf than cultivars considered tolerant of powdery mildew. Aphid numbers were not related to flower color or leaf area, but tall and semi-dwarf cultivars had significantly more aphids than dwarf or medium-sized cultivars. Mean number (± SE) of aphids per leaf per sample date varied from a low of 6.2 ± 1.7 on ‘Centennial Spirit’ to 84.8 ± 19.1 on ‘Biloxi’.
Distribution of Trialeurodes vaporariorum and Bemisia tabaci (Homoptera: Aleyrodidae) on Some Greenhouse-grown Ornamental Plants
Authors: Liu Tong-Xian , Oetting Ronald D. , Buntin G. David
Published: September 2017

The within-plant and between-plant distributions of all stages of both greenhouse whitefly (GHWF), Trialeurodes vaporariorum (Westwood) on poinsettia, chrysanthemum and gerbera daisy, and sweetpotato whitefly (SPWF), Bemisia tabaci (Gennadius) on poinsettia, were examined using Taylor's power law (s2 = amb) and Iwao's patchiness () methods. We found that all developmental stages of the two whitefly species on all plants examined were aggregated within and between plants. The vertical distribution of whitefly stages is stratified among leaves within the plant with respect to leaf age rather than relative height of the leaves on the plants. Most of the adults, eggs and the first-instar nymphs occurred on young leaves. The second- and third-instar nymphs occurred on middle-aged leaves, and most of the pupae and empty pupal cases occurred on middle-aged and older leaves. Comparison of whitefly counts from the different combinations of top, middle, and bottom leaves with the whole-plant counts on poinsettia was correlated and these leaves can be sampled as an indication of population levels within a greenhouse population.
Annual Variation in Stink Bug (Heteroptera: Pentatomidae) Seasonal Abundance and Species Composition in Georgia Soybean and Its Impact on Yield and Quality
Authors: McPherson R. M. , Douce G. K. , Hudson R. D.
Published: September 2017

Six soybean fields in southwest, south central and southeast Georgia were sampled weekly, beginning in mid-June and continuing until mid-October 1987–1991, for the presence of stink bug pests. Nezara viridula (L.), Acrosternum hilare (Say), Euschistus servus (Say), and Piezodorus guildinii (Westwood) comprised over 98% of the stink bug complex during this period, although eight other pest species plus three predatory species also were encountered. Stink bug population densities began to steadily increase in mid-August as the pods began to fill with seeds and peaked in mid-September to early October. Piezodorus guildinii accounted for over 13% of the total stink bug complex in 1987, but was present at low densities (less than 1%) the next four seasons. The three years when stink bug pests caused economic losses to soybean (1988, 1989 and 1991), the high population levels were due to high numbers of N. viridula. The years with low seasonal stink bug populations (1987 and 1990) had near equal numbers of the major pest species. When the stink bug complex exceeded the current treatment threshold level of 9 per 25 sweeps, significant reductions in soybean yield and quality were documented.
Incidence of Aphids (Homoptera: Aphididae) and Associated Potyviruses in Summer Squash in Arkansas
Authors: Hander C. A. , McLeod P. J. , Scott H. A.
Published: September 2017

A field study conducted in two Arkansas locations determined that five aphid species, Aphis craccivora Koch, Aphis gossypii Glover, Acyrthosiphon pisum (Harris), Rhopalosiphum maidis (Fitch) and Myzus persicae (Sulzer), were associated with yellow summer squash, Cucurbita pepo, L. Each aphid species vectors potyviruses of cucurbits. Although aphids were readily trapped with water and sticky flag traps, few aphids were observed on plants, and no vigorous aphid colonies were detected. In south central Arkansas (Benton), no virus-infected plants were observed in early plantings. Watermelon mosaic virus was detected in late squash plantings at Benton and varied from 0 to 23.2% of the total plants. In western Arkansas (Mulberry), papaya ringspot virus rapidly infected summer squash and resulted in complete loss of marketable fruit. The rapid and severe infection was attributed to close proximity of an infected squash planting.
Influence of Planting Date on the Seasonal Abundance of Tobacco Budworms (Lepidoptera: Noctuidae) and Tobacco Aphids (Homoptera: Aphididae) on Georgia Flue-Cured Tobacco
Authors: McPherson R. M. , Bondari K. , Stephenson M. G. , Severson R. F. , Jackson D. M.
Published: September 2017

The influence of planting date of flue-cured tobacco, Nicotiana tabacum L., on the seasonal abundance of tobacco budworms, Heliothis virescens (F.), and tobacco aphids, Myzus nicotianae Blackman, was examined in field plots in Georgia during 1987–89. Tobacco aphid population densities (aphids per plant) were influenced by yearly effects; however, tobacco budworm populations (budworms per 10 plants) were similar among the three years. A planting date (PD) effect (late March, mid-April, late April) was observed for tobacco aphids only in 1989, when higher population densities occurred in the late-planted tobacco. Planting date influenced tobacco budworm population densities in two of the three years. Significant differences in tobacco aphid populations were detected between PD's in all three years for the weekly samples in June and July, the period when seasonal aphid densities were the highest. Population peaks were higher in the mid-and late planting dates, except in 1987 when high aphid densities (3000 per plant) occurred only during the early planting date. Weekly differences in tobacco budworm populations also were detected among planting dates on many sampling dates throughout the season in all three years. Tobacco budworms occurred earliest in the early-planted tobacco, but peak densities were highest in the late-planted tobacco. Both tobacco budworm and tobacco aphid populations declined after the plants were topped (terminal floral branch removed) and a fatty alcohol sucker control was applied.
Field-Testing Pheromone Traps for Predicting Masked Chafer (Coleoptera: Scarabaeidae) Grub Density in Golf Course Turf and Home Lawns
Authors: Potter Daniel A. , Haynes Kenneth F.
Published: September 2017

Sticky traps baited with crude female extract of the southern masked chafer, Cyclocephala lurida Bland, were tested at 28 sites on a golf course and on 27 individual home lawns to determine if the numbers of males captured in short-term trapping could be used to predict subsequent grub densities. Hexane rinses of female beetles were effective in luring males to traps. There was no correlation between male captures and local densities of grubs on the golf course, where movement of beetles between adjacent areas may have confounded our ability to discriminate among high- and low-density sites. In contrast, there was significant, albeit weak correlation (r2 = 0.25) between male captures and subsequent larval populations in home lawns, even though trapping was restricted to only two nights due to limited availability of crude female extract. Identification and synthesis of the C. lurida sex attractant would allow season-long trapping, which could provide a more accurate assessment of beetle populations and prediction of grub densities at particular turfgrass sites. The fact that most home lawns sampled did not develop damaging infestations underscores the need for improved methods of sampling and risk assessment to avoid unnecessary preventative treatments.
Emergence of Male-Sterile Heliothis virescens (Lepidoptera: Noctuidae) Backcross Moths at a Central Release Point and Their Resulting Spatial Distribution
Authors: Laster M. L. , Hardee D. D. , Roberson J. L.
Published: September 2017

Heliothis virescens backcross moths are most effectively released in wide-area release programs from pupae placed in the field prior to moth emergence. A significantly greater moth emergence was obtained in the field from unharvested pupae in rearing trays than was obtained from harvested pupae. Mating, oviposition, and egg viability of emerged female moths were not adversely affected by handling procedures. Moths released from emergence containers were recovered in the most distant trap, 5.5 km, from the release point. However, the greatest number of released moths was captured in pheromone traps within 1.7 km of the release point.
Yellowjacket (Hymenoptera: Vespidae) Repellency by Natural Products of Paper Wasps and Avon's Skin-so-Soft©
Authors: Henderson Gregg , Blouin David C. , Jeanne Robert L.
Published: September 2017

Methyl palmitate and butyl palmitate, ant repellents first isolated from the sternal glands of paper wasps, were tested with a methyl ester homolog, methyl myristate, and Avon's Skin-So-Soft Bath Oil© against foraging German yellowjackets. Repellency remained high for six days for all compounds except methyl palmitate. Avon's Skin-So-Soft© was the most repellent. We suggest that this is due to two active ingredients, isopropyl palmitate and mineral oil.
Habitat Preferences of Generalist Predators in Reduced-Tillage Corn
Authors: Clark M. Sean , Luna John M. , Stone Nicholas D. , Youngman Roger R.
Published: September 2017

Habitat preferences of generalist predators were evaluated by comparing their abundance among four reduced-tillage corn systems which differed in the degree of soil disturbance, quantity and structure of the surface mulch due to tillage, and cover crop management practices. Two sampling methods were used to collect predators, pitfall trapping and vacuum sampling. Although there was considerable difference in the composition of species collected with each method, similar trends in overall predator abundance were observed. Generalist predator abundance followed the gradient of ground cover. The treatment with the highest degree of mulch ground cover had the highest overall predator abundance while the treatment which was disked and without surface mulch had the lowest. Although most of the common species preferred those systems with the most ground cover, several species preferred the system with the least amount of ground cover.
Acoustical Detection of the Sweetpotato Weevil (Coleoptera: Curculionidae) in Sweet Potato2
Authors: Hansen James D.
Published: September 2017

Ultrasensitive acoustical equipment was used to detect larvae of the sweetpotato weevil, Cylas formicarius elegantulus (Summers) (Coleoptera: Curculionidae), in the sweet potato, Ipomoea batatas (L.). Methods of expressing results were evaluated with per cent audible as the best indicator of larval presence. Sound from moderately infested sweet potatoes (8 to 20 weevils/sweet potato) varied considerably even though infestation rates above 60 weevils/sweet potato resulted in sound throughout most of the observation period. Infested sweet potatoes were detectable after two weeks of weevil development; maximum values were observed a month after infestation. However, the substantial variation of the observation data precluded descriptive mathematical models based on infestation rate or weevil development. Disease processes also caused signals that were indistinguishable from those made by sweetpotato larvae. Other factors that influence detectability are also discussed.
Survival and Development of the True Armyworm Pseudaletia unipuncta (Haworth) (Lepidoptera: Noctuidae), on Endophyte-infected and Endophyte-free Tall Fescue
Authors: Eichenseer Herbert , Dahlman Douglas L.
Published: September 2017

True armyworms, Pseudaletia unipuncta (Haworth), were fed tall fescue leaves either infected or uninfected with the symbiotic fungus, Acremonium coenophialum Morgan-Jones and Gams. Young larvae fed endophyte-infected leaves weighed less than cohorts fed endophyte-free leaves, but developmental and survival rates were unaffected by endophyte infection. Older instar larvae fed endophyte-infected leaves weighed the same as those larvae fed endophyte-free leaves. Pupal weights also were unaffected by endophyte infection. These results were similar to recent studies conducted with other armyworm species and suggest that endophyte infection in tall fescue does not enhance resistance to a number of lepidopteran larvae.
Predation of Corn Earworm (Lepidoptera: Noctuidae) Eggs and Young Larvae by Orius insidiosus (Say) (Heteroptera: Anthocoridae) on Grain Sorghum in a Greenhouse
Authors: Jacobson D. A. , Kring T. J.
Published: September 2017

Individual adult, fourth- and second-instar Orius insidiosus (Say) were caged for 24 h on branches of grain sorghum panicles with combinations of 0, 2, or 4 corn earworm eggs and 0, 2, or 4 first instar earworms, excepting 0 eggs and 0 larvae. Individual adult O. insidiosus also were caged for 24 h with 2 second-instar corn earworms. In cages with corn earworm eggs and first instars, predation by all stages of O. insidiosus on one stage of corn earworm was not significantly influenced by the number of the other stage available. The number of corn earworm eggs shriveled or missing, indicative of predation by O. insidiosus, was highest for cages with O. insidiosus adults (65% for either egg density). In cages with fourth-instar O. insidiosus, the percentage of corn earworm egg shriveled or missing was 45% with 2 eggs available and 32% with 4 eggs available. At all densities of eggs, the number of eggs shriveled or missing in cages with second-instar O. insidiosus was not significantly higher than in control cages. The number of first-instar corn earworms shriveled or missing was highest with fourth-instar O. insidiosus (≈ 52% loss at either larval density). Approximately 47% of larvae at both densities were shriveled or missing in cages with adult O. insidiosus. As was the case with eggs, the number of corn earworm larvae shriveled or missing in cages with second-instar O. insidiosus was not significantly different from that for the controls. Predation on second-instar corn earworms by adult O. insidiosus was not significant.