bluuebunny/crossref_metadata_2025 huggingface dataset:
Early Season Application of a Baculovirus for Area-Wide Management of Heliothis/Helicoverpa (Lepidoptera: Noctuidae): 1992 Field Trial
Authors: Bell M. R. , Hardee D. D.
Published: September 2017

A 9.6-km diam area in the intensive cotton-growing region of the Mississippi Delta was treated with an entomopathogenic virus to determine the effect on populations of adult tobacco budworms, Heliothis virescens (F.), and bollworms, Helicoverpa zea (Boddie), emerging from early season weed hosts. Four aircraft were used to treat ≈ 7,106 ha during 24–28 April at a rate of 100 larval equivalents per ha. Emergence data from cages placed over treated and untreated areas indicated that virus treatments reduced tobacco budworm emergence by 80.6% and bollworm emergence by 46.2%. During the emergence period, tobacco budworm traps in the area surrounding the treated area averaged 11.4 moths per trap per night. Average trap capture per trap per night in the center (6.4 km diam) of the treated area was 6.4 moths, a reduction of 43.9% compared with the untreated area. Correspondingly, reduction in trap counts for bollworm in the center was 21% when compared with the untreated area.
Argentine Ant (Hymenoptera: Formicidae) Foraging Activity Response to Selected Containerized Baits
Authors: Forschler Brian T. , Evans G. Michael
Published: September 2017

Bait acceptance and effect of toxic bait consumption on the foraging activity of field colonies of Argentine ants, Linepithema humile (Mayr), were assessed. Nine individual colonies were randomly assigned to receive one of three treatments: a containerized bait containing 0.5% sulfluramid in a peanut butter matrix, a containerized bait containing 0.9% hydramethylnon in an insect pupae-fish meal matrix, and an untreated control. Ant foraging activity was measured using honey-water monitoring stations placed at 0, 1, and 3 m from the colony nest-site. Both containerized baits reduced ant foraging activity to zero ants per monitor within 6 wks, if the equivalent of one containerized bait station was consumed by the colony.
Toxicity of Carbaryl toward the Southern Pine Beetle in Filter Paper, Bark and Cut Bolt Bioassays
Authors: Zhong He , Hastings Felton L. , Hain Fred P. , Werner Richard A.
Published: September 2017

Loblolly pine bolts sprayed with 2% carbaryl (Sevimol® 40% A. I. Flowable) and 1% chlorpyrifos were exposed to southern pine beetle, Dendroctonus frontalis Zimmermann. Chlorpyrifos treatment effectively prevented attack by southern pine beetle; however, the bolts were not protected by 2% carbaryl. For the carbaryl-treated bolts, the number of egg niches and larval mines were significantly reduced. However, the number of adult beetles entering the host, the length of the parent galleries, the number of pupal chambers, brood adults, and emergence holes were not significantly (P = 0.05) different from untreated control bolts. A bark surface assay indicated that 2% carbaryl killed < 50% of the beetles at 24 h. Filter paper assay showed that the LC50 value was 0.07% and 0.01% at 24 and 48 h, respectively.
Investigation of Antixenosis and Antibiosis as Mechanisms of Resistance in Rice to the Rice Weevil (Coleoptera: Curculionidae)
Authors: N'Guessan F. K. , Quisenberry S. S. , Linscombe S. D.
Published: September 2017

Five rice lines (8721941, 8723463, 8723518, 8725417, 8725454) were evaluated in the greenhouse in 1991 and 1992 for resistance to the rice water weevil, Lissorhoptrus oryzophilus Kuschel. These lines were selected from a preliminary field evaluation of 40 Louisiana rice breeding lines in 1990, based on low rice water weevil larval populations on roots. Resistance was assessed using the total larval population associated with the root system of each line. Significant (P < 0.05) differences were found among the lines tested with regard to rice water weevil larval populations during both years. Lines 8723518, 8725417, and 8725454 had significantly (P < 0.05) lower numbers of rice water weevil larvae than the susceptible check cultivar (Mars), indicating that they contain resistance to the rice water weevil.
Effects of Spined Soldier Bug (Hemiptera Pentatomidae) Augmentation and Sticky Barrier Bands on Gypsy Moth (Lepidoptera: Lymantriidae) Density in Oak Canopies2
Authors: Thorpe Kevin W. , Webb Ralph E. , Aldrich Jeffrey R. , Tatman Kathy M.
Published: September 2017

The effects of sticky barrier bands, augmentative releases of the spined soldier bug, Podisus maculiventris (Say), and the deployment of P. maculiventris pheromone on gypsy moth, Lymantria dispar (L.), larval density in the canopy of oak trees were tested. Sticky barrier bands used alone reduced larval gypsy moth density by ≈35%. The release of 5,810 P. maculiventris nymphs per tree or the deployment of P. maculiventris pheromone to trees on which sticky barrier bands had been applied had no additional effect on gypsy moth larval density. None of the treatments affected the number of gypsy moth egg masses produced. Significantly more P. maculiventris adults were observed on trees with the pheromone, but higher numbers of nymphs were not subsequently observed on these trees. Counts of gypsy moths beneath burlap bands prior to gypsy moth pupation were about four times higher on unbanded than on banded trees, but counts of pupae beneath burlap bands did not differ between treatments.
Preferences of Japanese Beetle and Southern Masked Chafer (Coleoptera: Scarabaeidae) Grubs Among Cool-Season Turfgrasses
Authors: Crutchfield Berry A. , Potter Daniel A.
Published: September 2017

Feeding preferences of Japanese beetle, Popillia japonica Newman, and southern masked chafer, Cyclocephala lurida Bland, grubs for six common cool-season turfgrasses were evaluated in choice tests in the greenhouse. On the basis of larval distributions, Popillia japonica consistently preferred perennial ryegrass, Lolium perenne L., over all other turfgrasses tested. In contrast, C. lurida showed no consistent pattern of preference. Presence of one grub species did not affect distribution of the other species. Grubs did not discriminate between tall fescue, Festuca arundinacea Schreb., infected with the endophyte Acremonium coenophialum Morgan-Jones & Gams and endophyte-free tall fescue.
Behavioral Interactions Between the Hyperparasitoid Mesochorus discitergus (Hymenoptera: Ichneumonidae) and Four Species of Noctuid Caterpillars: Evasive Tactics and Capture Efficiency
Authors: Baur M. E. , Yeargan K. V.
Published: September 2017

The hyperparasitoid, Mesochorus discitergus (Say), oviposits into larvae of primary parasitoids while the latter are developing inside various lepidopteran hosts. To accomplish hyperparasitism, M. discitergus must capture the lepidopteran larvae. We studied the evasive behaviors of 2nd-, 3rd-, and 4th instar Helicoverpa zea (Boddie) (corn earworm), Pseudoplusia includens (Walker) (soybean looper), Spodoptera frugiperda (J. E. Smith) (fall armyworm), and 2nd- and 4th-instar Plathypena scabra (Fabricius) (green cloverworm), as well as the effectiveness of these tactics in eluding capture by M. discitergus females. Most individuals of all instars of corn earworm and fall armyworm made minimal efforts to escape. Although not commonly used by corn earworm and fall armyworm, their occasional vigorous responses were effective in deterring M. discitergus females. Dropping from a leaf, either unattached or attached by a thread, was also effective for preventing capture of those two noctuid species. Soybean loopers and green cloverworms responded much more actively. Second-instars of both species dropped off the leaf on a thread, while 3rd- and 4th-instar soybean loopers commonly used vigorous responses. Fourth-instar green cloverworms used vigorous responses and dropping off the leaf. Overall, 68% of the caterpillars using the vigorous response were captured, while 39% of those dropping on a thread and about 26% of those dropping off a leaf, unattached by a thread, were captured. Green cloverworms and soybean loopers were more difficult to capture than corn earworms and fall armyworms.
Use of Ceralure and Trimedlure in Mediterranean Fruit Fly (Diptera: Tephritidae) Mass-Trapping Tests
Authors: Avery J. W. , Chambers D. L. , Cunningham R. T. , Leonhardt B. A.
Published: September 2017

Ceralure, a new potent and persistent attractant for the Mediterranean fruit fly, Ceratitis capitata (Wiedemann), was evaluated in a new technique which serves as an alternative to aerial application of male annihilation bait-sprays for eradication. Residual ceralure and trimedlure contents, release rates, and medfly captures using panels coated with ceralure and trimedlure in stickem were evaluated for effective attraction of male medflies. The lure/stickem coated panels may be more effective than the Jackson trap baited with the “standard” trimedlure plug dispenser.
Seasonal Phenology and Overwintering of Mantispa viridis Walker (Neuroptera: Mantispidae) in South Carolina
Authors: Brushwein Jeffrey R. , Hoffman Kevin M. , Culin Joseph D.
Published: September 2017

Captures of immatures and adults of Mantispa viridis Walker indicate this species has at least three distinct generations per year in the Clemson area of South Carolina, with an occasional fourth one in late fall and early winter. Mark-recapture studies show that M. viridis adults are rarely recaptured. Experiments exposing adults and immatures to ambient fall and winter temperatures in the Upper Piedmont of South Carolina resulted in the death of all adults by December, but 33% of the larvae emerged as adults the following spring from late February through May. The ability to survive prolonged freezing weather as immatures inside spider egg sacs may allow M. viridis to inhabit the colder regions of its range.
Mechanisms of Insecticide Resistance in a Strain of Cat Fleas (Siphonaptera: Pulicidae)
Authors: Hinkle Nancy C. , Wadleigh Richard W. , Koehler Philip G. , Patterson Richard S.
Published: September 2017

Possible mechanisms of insecticide resistance were investigated in a known-resistant strain of cat fleas, Ctenocephalides felis Bouché. In the acetylcholinesterase study, ability of two insecticides, propoxur and chlorpyrifosoxon, to inhibit the activity of the enzyme was investigated using the Ellman method. In both cases, at least twice the amount of insecticide was required for 50% enzyme inhibition in the resistant fleas vs the susceptible fleas. Additionally, there was a significant difference in levels of glutathione transferase in the resistant strain of fleas compared with the susceptible strain. These results indicate that both insensitive acetylcholinesterase and detoxification via glutathione transferase conjugation may be involved in the insecticide resistance mechanisms of this strain of fleas.
Effects of Pheromone Trap Design and Placement on Capture of Male Cydia caryana (Lepidoptera: Tortricidae: Olethreutinae) in Alabama Pecan Orchards and the Relationship of Trap Captures to Fruit Infestation
Authors: McVay John R. , Eikenbary Raymond D. , Morrison Robert D. , Kouskolekas Costas A. , Dennison Michael
Published: September 2017

The Pherocon Ic trap captured the greatest number of Cydia caryana (Fitch) adult males and all trap designs appeared to represent population trends equally well. Pooled data from all trap height experiments indicate that traps placed 9.14 m above the orchard floor captured significantly more adult males than those placed at 4.57 m height. Horizontal placement of traps within the tree canopy indicated a significantly greater capture in the central portion of the canopy than at other locations. Correlations between the total capture of male adults and the rate of fruit infestation were not significant.
Pirimiphos-Methyl Residues and Control of Greenhouse Whitefly (Homoptera: Aleyrodidae) on Seven Vegetables
Authors: Antonious George F. , Snyder John C.
Published: September 2017

A gas chromatographic analysis of pirimiphos-methyl, Actellic®, residues on four leafy vegetables (celery, radicchio, cabbage and kohlrabi) and three fruity vegetables (green beans, pepper and cucumber) is reported. The method proved to be accurate and reliable for residue estimation with recoveries of 90–96% from fortified vegetable tissues, depending on the crop species and the part of the plant analyzed. Initial deposition of pirimiphos-methyl and its disappearance rate on the different types of plant surfaces varied widely. Residue disappearance rates varied from rapid on cucumber fruits (t½ = 1.8 d) to slow on pepper fruits (t½ = 4.3 d) over a 42-day period. On leaves, green beans had the highest dissipation rate (t½ = 2.0 d) while pepper had the lowest (t½ = 4.7 d). Waiting periods (preharvest safety intervals) on each crop were also determined. The potential of pirimiphos-methyl was tested as a candidate for greenhouse whitefly, Trialeurodes vaporariorum (Westwood) (Homoptera: Aleyrodidae) control. Cucumber and bean foliage were preferred by greenhouse whitefly. One day following application of Actellic® 5E emulsifiable concentrate at the rate of 4.5 g (AI)/L of liquid spray, whitefly populations were reduced significantly on both cucumber (88%) and beans (96%). Pirimiphos-methyl may be a useful candidate for control of greenhouse whitefly and other insects in home gardens based on its effectiveness and human safety.
Distribution of Natural Enemies of Euonymus Scale, Unaspis euonymi (Comstock), in Virginia
Authors: Jefferson D. K. , Schultz P. B. , Bryan M. D.
Published: September 2017

The colonization of Chilocorus kuwanae (Silvestri) (Coleoptera: Coccinellidae) and Cybocephalus nipponicus (Endrody-Younga) (Coleoptera: Nitidulidae), introduced predators of euonymus scale, Unaspis euonymi L., was evaluated on evergreen euonymus scale, Euonymus japonica L., by regional and statewide surveying. This study determined the statewide distribution of the native parasites of euonymus scale, Aspidiotiphagus spp. and Encarsia spp. (Hymenoptera: Aphelinidae). Highest recovery incidences were from 18 of the 41 survey sites on 25 May. The survey established the survival and dispersal of C. kuwanae in metropolitan areas of Virginia with recoveries in 8 of the 12 cities.
Ichneumon promissorius (Erichson) (Hymenoptera: Ichneumonidae): Factors Affecting Fecundity, Oviposition, and Longevity
Authors: Carpenter J. E.
Published: September 2017

Ichneumon (=Pterocormus) promissorius (Erichson) (Hymenoptera: Ichneumomidae), a native of Australia, is a pupal parasitoid which searches the soil surface for host pupation sites, burrows into a pupal gallery, and oviposits in the host pupa. Fecundity and rate of oviposition were influenced by the mating status of females, the host from which females developed, and the frequency in which females were exposed to hosts. Virgin females continued laying eggs many days after mated females had stopped. A preoviposition period of 17 d in mated females did not affect the oviposition curve or the number of eggs laid, suggesting that the oogenesis is arrested until female wasps are exposed to host pupae. Female wasps exposed to pupae for 24 h every fifth day lived longer than female wasps continuously exposed to pupae. However, females that were continuously exposed to pupae laid more eggs. Virgin females reared on Spodoptera exigua (Hübner) pupae laid fewer eggs than virgin females reared on Helicoverpa zea (Boddie) pupae. These data will be important in evaluating the potential of I. promissorius as a biological control agent for pest species in the United States and will be useful in developing laboratory rearing procedures for I. promissorius.
Seasonal Variations in the Silk Yield Contributing Characters of Forty-two Strains of the Silkworm, Bombyx mori (Lepidoptera: Bombycidae)
Authors: Bhargava S. K.
Published: September 2017

Forty-two strains of the silkworm, Bombyx mori (L.), collected from China, Japan, Vietnam, South Korea, Brazil, India, and France were reared in the spring, summer and autumn seasons during 1991–92 at the Regional Station of Central Sericultural Research and Training Institute, Coonoor, Tamilnadu State, India. Analyses were made on five silk yield-contributing characters, namely pupation rate, cocoon weight, shell weight, cocoon shell ratio, and silk filament length. Results indicated the superiority of the following strains for all the above mentioned characters: 14M and JC2P (in spring); NBJPO and JC2P (in summer); and M2, NBJPO and SPJ2 (in autumn). The importance of rearing a given strain of silkworm in the optimal season for its maximum economic value in terms of silk yield is discussed.
Structural Properties of the Female Accessory Gland in the Stable Fly, Stomoxys calcitrans
Authors: Cook Benjamin J. , Pryor Nan W.
Published: September 2017

The accessory reproductive glands of the female stable fly are translucent structures that run parallel to the common oviduct when the ovipositor is extended. The only muscles found associated with the gland were those at either end of the long tube of simple cuboidal epithelial cells. The posterior region of each gland is connected to the anterior vagina by means of a valve of circular muscle. The myofibrils of the valve are separated into sarcomeres of irregular alignment with Z disks that appear as discontinuous rows of dense bodies. Transections through the Z disk region also revealed a perforated character which is common in muscles that have the ability to super contract. The sarcolemma of many cells have tubular invaginations that correspond to the T-system of tubules found in most muscles. Terminal axons with both synaptic vesicles and larger neurosecretory granules were found in close apposition to muscle fibers of the valve. Large vacuoles (with a mean of 26.36 μm and a SD = ± 2.09) were the most prominent structures in the cytoplasm of the glandular epithelium. The fine structure of these vacuoles showed a microvillar border and a central portion that contains clumps of secretory material in a granular matrix. Many vacuoles also contain dense inclusion bodies while other inclusion bodies were observed in apical membranous networks just beneath the cuticular intima. Such ultrastructural features suggest a largely merocrine type secretion for this gland.
Effect of Bacillus thuringiensis Application Interval on European Corn Borer (Lepidoptera: Pyralidae) Control in Sweet Corn
Authors: Bartels David W. , Hutchison William D. , Fritz Vincent A. , Klacan George R.
Published: September 2017

Ground-applied treatments of two commercial Bacillus thuringiensis subsp. kurstaki formulations (MVP and Dipel ES) and tank-mixes with a pyrethroid (Ambush 2E) were evaluated for control of European corn borer, Ostrinia nubilalis (Hübner), larvae in sweet corn. Treatments were applied at average intervals of 3.4, 5, 7, and 10 days to determine field persistence. Manual infestations of first-instar O. nubilalis were used to augment natural populations. During both years, there were no significant interactions between application interval and treatment for all dependent variables tested, including late instars per ear, percent marketability, yield, and predator density. Regardless of application interval, MVP provided greater larval control than Dipel ES. However, the decline in efficacy of the encapsulated MVP formulation occurred at the same rate as that of the non-encapsulated Dipel ES formulation over the 3.4 to 10-d intervals. Tank-mixes of B. thuringiensis + low-rate permethrin provided no additional control compared with low-rate permethrin alone. Given the infestation levels present in this test, neither B. thuringiensis formulation provided control sufficient to maintain current processor standards of 5–10% infested ears at harvest.
Seasonal Activity of Meloe americanus (Coleoptera: Meloidae) in a Mississippi Old-field Habitat
Authors: Young O. P.
Published: September 2017

Adults and triugulin larvae of Meloe americanus Leach were collected by pitfall trapping and sweepnetting of foliage during 14 consecutive months at an old-field site in Washington Co., MS. Adults were captured in pitfalls from December to April, and triungulins were captured in pitfalls and attached to Apoidae (Hymenoptera) hosts on foliage only from April to May and from September through October. Several scenarios are proposed to explain this unusual pattern of disjunct triungulin seasonal occurrence. Spatial patterns of adult and triungulin occurrence are correlated with successional changes in the habitat, and attachment sites of triungulin larvae on Apoidae hosts are documented.
Effect of Short-Term Releases of Chrysoperla rufilabris (Neuroptera: Chrysopidae) Against Silverleaf Whitefly (Homoptera: Aleyrodidae) in Field Cages2
Authors: Legaspi Jesusa Crisostomo , Correa J. A. , Carruthers R. I. , Legaspi B. C. , Nordlund Donald A.
Published: September 2017

We studied the effect of different lacewing (Chrysoperla rufilabris [Burmeisterl release rates on control of the silverleaf whitefly, Bemisia argentifolii Bellows and Perring, inside field cages in organically-grown watermelon and in Lablab purpureus, a leguminous forage crop. Second-instar C. rufilabris larvae were released at rates of 0 (control), 10, 25, and 50 per cage (0.37 m2 area). Whitefly counts were made prior to release and compared with those taken 48 h after release of the lacewings. In the watermelon field, the control had approximately 35% more whiteflies over the entire season as compared to the predator treatment with the highest whitefly counts (25 lacewings per plant). The effects of predator releases were most evident during the second half of the season. However, higher rates of predator release did not result in increased pest suppression. No significant patterns of prey suppression were detected in the legume field, possibly because prey densities were already too high at the start of the experiment. Whitefly population dynamics in the lablab was apparently determined by environmental factors and crop phenology, rather than by predation. Possible reasons are presented for observed differences in degrees of pest suppression afforded by lacewing larvae in order to optimize control of the whitefly populations.
Effects of Chilling of Bemisia argentifolii (Homoptera: Aleyrodidae) Infesting Cabbage
Authors: Zalom Frank G. , Castañé Cristina , Gabarra Rosa
Published: September 2017

Cold temperatures affected the biology of Bemisia argentifolii Bellows and Perring on cabbage both directly and indirectly. Continuous chilling of 0°C and 4°C significantly increased mortality of adults and eggs. Variable daily chilling of 0°C for 6 h and then greenhouse conditions for the remainder of the day increased adult mortality but did not affect egg mortality for the 10 days of exposure. Prior plant exposure to 0°C resulted in reduced adult B. argentifolii preference and increased adult mortality. Previous 0°C and 4°C plant exposure also had an impact on within plant distribution of adults and eggs. On nonchilled and recently chilled plants, adults and eggs were found on the youngest (highest) leaves. On plants chilled at 0°C and 4°C three and five days before infestation, adults and eggs were found on lower leaves. Lower immature mortality was recorded on the nonchilled plants than on the chilled plants.
Spore-Toxin Interactions and Sublethal Effects of Bacillus thuringiensis in Spodoptera frugiperda and Pseudoplusia includens (Lepidoptera: Noctuidae)
Authors: Nyouki F. F. R. , Fuxa J. R. , Richter A. R.
Published: September 2017

Interactions between the spores and δ-endotoxins of Bacillus thuringiensis Berliner were tested in a low-susceptibility insect, Spodoptera frugiperda (J. E. Smith). The spores (formulation MYD™) and one δ-endotoxin (formulation MVP™) had additive effects on mortality at a MVP™ dose of 117,500 μg/g of diet (P < 0.01) and synergistic effects at a MVP™ dose of 235,000 μg/g diet (P < 0.01). The spores and another δ-endotoxin (formulation MYX™) were antagonistic at a MYX™ dose of 117,500 μg/g diet (P < 0.01) and additive at a MYX™ dose of 235,000 μg/g diet (P < 0.01). The two δ-endotoxin formulations were additive with one another (P < 0.01). Sublethal concentrations of MVP™ fed to larvae retarded the development of larvae and pupae for 5 d (P < 0.01) and 1.2 d (P < 0.01), respectively, and decreased pupal weight by 48 mg (P < 0.01). The spore formulation did not affect (P > 0.05) pupal weight or the life span of larvae or pupae. Median lethal concentrations of MVP™ and MYX™ were 6,904 and 7,561 × greater, respectively, in S. frugiperda than in Pseudoplusia includens (Walker). In P. includens, sublethal concentrations of MVP™, MYX™, and Dipel™ fed to larvae significantly (P < 0.05) reduced pupal weight and increased pupal life span compared to control insects. MVP™ and Dipel™ increased larval life span significantly (P < 0.05), but MYD™ did not.
Subterranean Termite, Reticulitermes spp. (Isoptera: Rhinotermitidae), Colony Response to Baiting with Hexaflumuron Using a Prototype Commercial Termite Baiting System
Authors: Forschler Brian T. , Ryder John C.
Published: September 2017

Six subterranean termite colonies, representing two species, Reticulitermes flavipes and R. virginicus were characterized and baited during the spring and summer of 1993 at three locations in the Piedmont Soil Zone in west-central Georgia. Characterizations included population and foraging territory estimates, indices of activity, wood consumption rates, and number of termites collected per site per visit. The four characterized colonies that were baited averaged 43,000 termites per colony and occupied foraging territories averaging 16 m2. An additional 12 colonies were baited in 1994 simulating a commercial bait application where only indices of termite activity were recorded. Each termite colony was baited using a prototype baiting system which included the active ingredient hexaflumuron. Activity of each colony was monitored before, during, and after baiting. Three of the characterized colonies were baited during June and July 1993, and activity was undetectable within 3 months. One colony, baited in September, continued to show activity for 8 months. Six of the colonies baited in 1994 showed no activity at least 5 months after bait acceptance, two colonies removed bait starting in September and were still showing activity in May, two colonies did not revisit monitors following bait stake attack, and one colony did not accept bait and remained active in the nearby monitor. Colony characterizations, baiting procedures, measures of termite activity, and the difficulties of determining termite baiting efficacy from field trials are discussed.
Insect Pests and Impact on Late-Season Tomato in Arkansas
Authors: McLeod P. J. , Katayama R. K. , Sweeden M. B. , Burleigh J. G. , Giese W. G. , Burks R. A.
Published: September 2017

The recent release of heat-tolerant tomato cultivars has resulted in increased interest in expanding fresh market tomato from historically early production to late summer and fall in Arkansas. Although insects are generally of minor importance in early production, much concern exists with the greater numbers of insects occurring later during the season. Insect frequency and impact on tomato were determined in studies conducted in northwestern and southern Arkansas in 1993 and 1994. The corn earworm, Helicoverpa zea (Boddie), was the most damaging insect in both locations during both years. Corn earworm larvae were detected throughout the study and caused extensive fruit damage. At the northwestern location, 81.6% of all harvested fruit was damaged by corn earworm larvae in 1993. Although thrips were present at both locations throughout the season, no plants infected with tomato spotted wilt virus were detected. Other potential insect threats, i.e., stink bugs, flea beetles and tomato pinworms, had no apparent effect on late-season production. Corn earworm management is well developed for early tomato production and should be easily adapted to late-season production. This should insure the success of late-season tomato production in Arkansas.
Descriptive Model of Phosphine Concentrations and Emission Rates During Controlled Aeration of Fumigated Tobacco Warehouses
Authors: Keever D. W. , Hamm L. A.
Published: September 2017

A model was developed to describe the emission of phosphine gas from the interior of a tobacco warehouse to the outside during controlled aeration after fumigation of the warehouse. We used a fan/stack exhaust system to control the aeration, but other systems can be used. Model inputs include phosphine concentrations in the warehouse just prior to aeration, warehouse characteristics, and characteristics of the system used to release phosphine. Model outputs for any time during aeration include the emission rate of phosphine from the warehouse, the phosphine concentration remaining in the warehouse, and suggested exhaust rates that help fumigators comply with regulatory standards on phosphine emission rates. (Exhaust rate refers to release of air/phosphine mixture from the warehouse [=volume/time], but phosphine emission rate refers to the amount of phosphine [=mass/time]). The model also calculates how much exhaust rates can be increased at regular time intervals to hasten aeration without exceeding the initial phosphine emission rate. The model can be used by fumigators to comply with regulatory standards on phosphine emissions, and by regulators to assess that compliance. Diffusion of phosphine from the packaged tobacco (cases) into the freespace of the warehouse and its impact on the model are discussed.
Seasonal Feeding by Phyllophaga crinita and Anomala spp. (Coleoptera: Scarabaeidae) Larvae in Northeastern Mexico
Authors: Rodriguez-del-Bosque L. A.
Published: September 2017

Larval feeding by Phyllophaga crinita (Burmeister) and Anomala spp. (mixed populations of A. flavipennis Burmeister and A. foraminosa Bates) was studied under simulated field conditions in northern Tamaulipas, Mexico. Each month from July 1994 to February 1995, 50 field-collected larvae of P. crinita and Anomala spp. were placed individually in plastic pots with soil and corn seeds, and damage was evaluated 10 d after seedling emergence. Secondinstar P. crinita caused 41% root loss in July, whereas third instars caused most damage (66–88% root loss) during July–September. Feeding by P. crinita decreased gradually from October to December, and ceased in January–February. In contrast, feeding by Anomala spp. peaked in July and again in November (73 and 53% root loss, respectively), a result of the bivoltine life cycle of these species in this region. The relationship of these findings to similar studies is discussed.
Diamondback Moth (Lepidoptera: Plutellidae) Contamination of Cabbage Transplants and the Potential for Insecticide Resistance Problems
Authors: Shelton A. M. , Kroening M. K. , Eigenbrode S. D. , Petzold C. , Hoffmann M. P. , Wyman J. A. , Wilsey W. T. , Cooley R. J. , Pedersen L. H.
Published: September 2017

Samples collected from 1989 to 1992 document that the diamondback moth, Plutella xylostella (L.) was introduced into New York in early spring on cabbage, Brassica oleracea capitata (L.), transplants grown in the southern United States. During 1989, transplant shipments from five transplant companies in Florida, Georgia and Maryland were sampled for P. xylostella. In 1989, average seasonal infestations per transplant company ranged from 1.3 to 3.5 P. xylostella per 100 transplants. During June, when the majority of transplants arrived in New York, P. xylostella infestations were as high as 12.8 insects per 100 transplants on an individual shipment. Infestations by cabbage looper, Trichoplusia ni (Hübner), imported cabbageworm, Artogeia (=Pieris) rapae (L.), and cabbage webworm, Hellula rogatalis (Hulst), on an individual shipment were as high as 19.7 insects per 100 transplants. Compared with a standard susceptible field population, the P. xylostella which were collected from transplants demonstrated moderate to high (> than 100-fold in one case) levels of resistance to permethrin or methomyl. In 1990, average seasonal infestations per transplant company varied from 0.3 to 12.0 P. xylostella per 100 plants, but an individual shipment from Florida had 30.4 P. xylostella per 100 transplants. A population of P. xylostella collected in 1990 from Florida transplants had >200-fold resistance to methomyl. Despite intensive treatments, a New York grower who used the transplants with high contamination of resistant P. xylostella was unable to achieve acceptable control in his field. Samples collected from 1989 to 1992 from a transplant grower in Maryland indicate that better management in the field can reduce contamination levels to < 0.5%. The introduction of P. xylostella, especially those resistant to insecticides, on transplants poses a serious threat to cabbage growers and interregional management strategies should be adopted.
Effects of a Nuclear Polyhedrosis Virus and a Fluorescent Brightener on Colonies of Spodoptera exigua (Hübner)
Authors: Hamm J. J. , Chandler L. D.
Published: September 2017

The beet armyworm, Spodoptera exigua (Hübner), is an important pest which is difficult to control because it is resistant to nearly all registered insecticides. A new commercial formulation of a nuclear polyhedrosis virus that is pathogenic to beet armyworm larvae, SPOD-X®, was tested with and without a fluorescent brightener, Tinopal LPW. The effects on larvae from six colonies of the beet armyworm which had recently been established from field collections in Georgia, Alabama and Mississippi were compared with a laboratory colony which had been maintained in the laboratory for 2 years. The LC50 was lower in all bioassays with SPOD-X in 0.25% Tinopal LPW than with SPOD-X in water, although in 3 of 12 bioassays the difference was not significant based on overlapping 95% confidence intervals. The mean LC50 for SPOD-X in water was 376 polyhedral occlusion bodies per cup (surface area 800 mm2). The mean LC50 for SPOD-X in 0.25% Tinopal LPW was 30 polyhedral occlusion bodies per cup. The LC50 for SPOD-X in water was not significantly different between the laboratory colony and 5 of 6 field-collected colonies when bioassayed concurrently. There was no significant difference in LC50 for SPOD-X in 0.25% Tinopal LPW between the laboratory colony and any of the field-collected colonies. Thus, Tinopal LPW enhanced the infectivity of SPOD-X for beet armyworm larvae in laboratory tests and reduced the variability of response of the beet armyworm colonies to the virus.
Evaluation of Natural Products as Antifeedants for the Pales Weevil (Coleoptera: Curculionidae) and as Fungitoxins for Leptographium procerum
Authors: Salom Scott M. , Gray Jodi A. , Alford A. Randall , Mulesky Melinda , Fettig Chris J. , Woods Steve A.
Published: September 2017

Four natural plant compounds (limonin, S (+) and R (−) carvone, and cucurbitacin) and one insect pheromone (verbenone) were evaluated for antifeedant activity against the pales weevil, Hylobius pales (Herbst), on Pinus strobus seedlings and for toxic activity against the pathogenic fungus, Leptographium procerum (Kendrick) Wingfield, which is vectored by H. pales to P. strobus. All compounds demonstrated significant antifeedant activity in a choice test on treated pine seedlings, but none completely eliminated feeding. Only cucurbitacin elicited a linear dose-response relationship, with significant activity occurring at concentrations as low as 0.10 μg/ml. The other compounds significantly reduced feeding at concentrations as low as 1 μg/ml (the lowest concentration at which they were tested). Total feeding activity was unaffected for all but one treatment (S (+) carvone at 1 μg/ml) when compared with feeding on the untreated control seedlings. It is, therefore, unlikely that the compounds in this study were toxic to the weevils during the 2 d evaluation period. In the fungitoxin test, all compounds except cucurbitacin suppressed germination of L. procerum spores. R (−) carvone was the most effective, allowing only 5% germination at 1 μg/ml, compared to 96% germination in the water solvent.
Attraction of Adult Plum Curculios (Coleoptera: Curculionidae) to Host-Tree Odor and Visual Stimuli in the Field
Authors: Butkewich Susan L. , Prokopy Ronald J.
Published: September 2017

Field tests were conducted to determine if plum curculios, Conotrachelus nenuphar (Herbst), responded to host odor and/or visual cues to locate host trees. Experiment 1 investigated the role of odor in host location. Host branchlets (apple leaves and fruit) were compared with non-host branchlets (maple leaves). Significantly more released color-marked plum curculios arrived on screen cages containing apple branchlets than on screen cages containing maple branchlets. Experiment 2 investigated the role of visual cues, with or without host odor, in host tree location. Plum curculios arrived preferentially on 60 cm wide × 130 cm tall sticky green rectangles (intended to mimic the canopy of a small tree) with associated caged apple branchlets than on sticky clear Plexiglas rectangles with caged apple branchlets or on sticky green or clear Plexiglas rectangles with caged maple branchlets. These data suggest that plum curculio adults may use both odor and visual cues to locate host trees during spring migration from overwintering sites.
Gonad-Specific Virus of Helicoverpa zea Does Not Affect Infectivity of Nuclear Polyhedrosis Virus
Authors: Hamm John J.
Published: September 2017

A gonad-specific virus (GSV), an enveloped, rod-shaped virus, which prevents the development of normal ovaries and testes of Helicoverpa zea (Boddie) (Lepidoptera: Noctuidae) has been suggested for use in biological control of H. zea (Raina an Adams 1995). Because the GSV resembles the Hz-1 virus which was described as a persistent infection in an H. zea tissue culture that inhibited infection by other viruses, this research was designed to determine if the GSV would interfere with infection of H. zea larvae by its homologous nuclear polyhedrosis virus (HzSNPV) which is currently being used in biocontrol of H. zea and H. virescens. In three of four tests, there was no significant difference in LC50 (i.e., the 95% confidence intervals overlapped) for HzSNPV in larvae from normal moths and larvae from moths injected with GSV. Surviving larvae from the GSV-injected moths produced 97.8 to 100% agonadal moths. This indicates that GSV does not protect agonadal larvae from infection by NPV. Thus, release of GSV into the natural population of H. zea should not interfere with use of the more virulent NPV for control H. zea.
Description of the Mature Larvae of Chrysis angustula Schenk and Hedychridium elegantulum Buysson (Hymenoptera: Chrysididae) and the Phylogenetic Importance of Larval Characters
Authors: Tormos J. , Asís J. D. , Gayubo S. F.
Published: September 2017

Mature larvae of Chrysis angustula Schenk, 1856, and Hedychridium elegantulum Buysson, 1887, are described. A discussion of the phylogenetic importance of the preimaginal structures of known mature larvae of the Chrysididae is offered.
Structural Properties of the Intrinsic Muscles of the Malpighian Tubules of the Female Stable Fly, Stomoxys calcitrans L.
Authors: Cook Benjamin J. , Pryor Nan W.
Published: September 2017

The four Malpighian tubules of the female stable fly, Stomoxys calcitrans L., were divided into an anterior dorsal and a posterior ventral pair. A marked structural divergence existed between the distal terminations of these two pairs. This divergence consisted primarily in the number and size of crystalline granules present in the respective distal regions. The terminal diameter of the dorsal tubules was at least twice that of the ventral tubules. Intrinsic muscles were found only in that short proximal section (ureter) of each pair of tubules that emptied into the midgut. Other regions of the tubules showed no evidence of a muscle sheath. The small intrinsic muscles (0.25 to 0.6 μm diam) of the ureter were visible under Nomarski optics at high magnification (600X). The muscle fibers were embedded in the basal regions of the large epithelial cells that line the lumen of the ureter. Occasionally, these muscles were arranged in a multilayered lattice. Myofibrils were separated into sarcomeres of irregular alignment with classical A (0.8 μm in length) and I bands. The Z disk consisted of discontinuous rows of dense bodies, and in partially contracted muscle some myofilaments of the A band passed between the dense bodies of the Z bands. T-system tubules and the sarcoplasmic reticulum were sparse to non-existent.
Orchard Management Effects on the Arthropod Community on Peach with Comparison to Apple
Authors: Brown M. W. , Puterka Gary J.
Published: September 2017

One hundred sixty-two species were recorded as part of the arthropod community associated with peach in eastern West Virginia. The community was composed of 33% phytophages, 35% insectivores, 14% scavengers, and 18% tourists. Diversity of the anthropod community was correlated inversely with intensity of orchard management. Comparing the phytophagous community on apple (from an earlier study) with that on peach, Lepidoptera comprised 49% on apple and only 31% on peach; Hemiptera comprised 9% on apple and 19% on peach. Diversity of the phytophagous arthropod community was significantly less in peach than in apple orchards, but was more similar in commercially-managed orchards than in unmanaged orchards. It is concluded that in commercially-managed peach and apple orchards insecticide use is the dominant factor controlling community structure, whereas, in unmanaged orchards the communities in peach and apple evolve into distinctly different communities. The presence of cyanogenic glycosides in peach, extrafloral nectaries on peach, and the relatively smaller species pool available to colonize peach are considered major factors for the difference in arthropod community structure in peach and apple.
Risk of Western Corn Rootworm (Coleoptera: Chrysomelidae) Damage to Continuous Corn in Virginia
Authors: Kuhar Thomas P. , Youngman Roger R. , Laub Curtis A.
Published: September 2017

Information on the risk of western corn rootworm, Diabrotica virgifera virgifera LeConte, damage to continuously-grown corn previously was lacking in Virginia, as well as other mid-Atlantic states. A field study was conducted in 1993 and 1994 comparing root damage, whole-plant yields, and silage quality in insecticide-treated and untreated sections of 32 continuous corn fields in Virginia. Approximately 28% of the fields had serious root damage exceeding a rating of 3.5 (1–6 scale) in sections not treated with a soil insecticide. Also, 19% of the fields had an economic loss in whole-plant yield due to corn rootworm feeding damage. Silage quality, as evidenced by percent crude protein and acid detergent fiber, was not significantly affected by corn rootworm feeding. Because much of the continuous corn acreage in Virginia is treated preventively with soil insecticides for corn rootworms, the results of this study suggest that a large percentage of this insecticide use is unnecessary.
Sperm Transfer in Gypsy Moths: Effect of Constant or Cyclic Temperature and Constant Light or Darkness during the Pupal Stage
Authors: Proshold F. I.
Published: September 2017

Sperm transfer and fertility of the gypsy moth, Lymantria dispar (L.), held as pupae under constant temperature and 24-h light, 24-h darkness, or a photoperiod of 16:8 (L:D) h were compared with males held in cyclic temperature and 24-h light, 24-h darkness, or a photoperiod of 16:8 (L:D) h. Constant temperature and constant light or darkness severely reduced its ability to transfer sperm. Males held under constant light were more severely affected than males held in darkness, but sperm transfer was not correlated with light intensity (between 80 and 3960 lux). Nearly all males held under constant light and most held under constant darkness were sterile or partially sterile. In either case, sterility was caused by poor sperm transfer. Females with a full complement of sperm were fertile regardless of holding condition of male pupae. The sterilizing effect of constant light or darkness was overridden by cyclic temperature of 28°C for 16 h and 22°C for 8 h. At a photoperiod of 16:8 h, pupae held in constant 28°C transferred less sperm than those held at 25°C. Pupae held at constant 30°C were sterile, but those held at 30°C for 16 h and 25°C for 8 h transferred similar quantities of sperm as males held at constant 28°C.
Areawide Population Dynamics of Silverleaf Whitefly (Homoptera: Aleyrodidae) and its Parasitoids in the Lower Rio Grande Valley of Texas
Authors: Legaspi B. C. , Legaspi J. C. , Carruthers R. I. , Goolsby J. , Hadman J. , Jones W. , Murden D. , Wendel L.
Published: September 2017

The population dynamics of the silverleaf whitefly (SLWF), Bemisia argentifolii Bellows and Perring (=sweetpotato whitefly, B. tabaci Biotype “B”, [Gennadius]), and its endemic parasitoids (mostly Encarsia spp. [Aphelinidae]) were monitored in a heterogeneous cropping area, consisting of cotton, cantaloupe and kenaf (tall fiber crop). To assess the suitability of the whitefly for areawide pest management, we compared estimates of population densities using different sampling methods and determined the effects of agronomic practices on the whitefly and parasitoid populations. There was no correlation between adult SLWF estimates using sticky traps and those counted directly on the leaves. However, counts of immatures using disk subsamples were found to be good predictors of whole leaf counts. SLWF counts were low in cotton, until the harvest period of cantaloupes, which may have triggered migration from cantaloupe to cotton. The determinants of emigration from cotton were less clear. High numbers of adults were migrating well before harvest or the application of a defoliant. One likely contributing factor in triggering whitefly migration was leaf senescence. Despite rather high adult densities sampled in kenaf, populations of immature SLWF were low, suggesting that it is not a preferred host. Parasitoid populations were high in the kenaf fields, causing 20 to 80% parasitism and suggesting that kenaf could serve as a reservoir of natural enemies within a larger cropping system. Parasitism in cotton was less than that in kenaf, usually at ~10 to 15%. Encarsia spp. sampled on sticky traps indicated significant activity of the adults in the cotton and kenaf fields, and much lower numbers in the cantaloupe. Because it is a dispersive and polyphagous pest, areawide suppression of SLWF must include the consequences of farming practices and cropping patterns in heterogeneous fields, especially when they are under different management.
Activity of the Extrinsic and Intrinsic Muscle Networks of the Malpighian Tubules and the Ureter in the Female Stable Fly, Stomoxys calcitrans (L.)
Authors: Cook Benjamin J. , Chen Andrew C. , Pryor Nan W.
Published: September 2017

The four Malpighian tubules observed in the female stable fly, Stomoxys calcitrans (L.), are divided into an anterior dorsal pair and a posterior ventral pair. Intrinsic muscles were found only in the short proximal section (ureter) of each pair of tubules that emptied into the midgut. Isolated preparations of the ureter demonstrated four types of organized rhythmic activity: compression, peristalsis, reverse peristalsis, and segmentation. Compression caused a momentary (0.4 to 0.6 sec) shortening of the longitudinal muscle fibers in a localized region of the ureter. Peristalsis was the dominant type of activity. Each wave progressed along the duct with a duration that ranged from 0.9 to 1.7 sec. Segmentation consisted of a localized annular constriction of the ureter without progression that lasted for a duration of 0.3 to 0.6 sec. The large distal ends of the dorsal pair of tubules showed spontaneous movement in situ. Close examination revealed a network of extrinsic muscle cells attached to the distal tubular ends. The motile properties of the extrinsic muscles were slower and not as complex as those of the ureter. The sequence from the resting state to contraction and return was much longer with durations that ranged from 10.8 to 27.1 sec. Also, the time for peak tension was 5 to 25.9 sec in duration. The extrinsic muscles did not show the organized and rhythmic activity observed in the ureter.