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The impact of a zoophytogenous, insect-free artificial diet and a secondary prey, pupae of Chinese oak silk moth Antheraea pernyi (Guérin-Méneville) (Lepidoptera: Saturniidae), on the developmental rate, life history parameters, and fertility was examined for F6, F9, and F12 consecutive generations for domesticated Arma chinensis (Fallou) (Heteroptera: Pentatomidae). This study showed that when fed an insect-free artificial diet during both the nymphal and adult stages, developmental times were prolonged, and fecundity, egg viability, net reproductive rates (R0), and intrinsic rates of increase (rm) declined. As a result, the cost to rear A. chinensis on the artificial diet approached 2.0 times the cost of rearing A. chinensis on pupae of A. pernyi. Future diet improvements should attempt to reduce developmental time, increase fecundity, and egg viability and use less costly nutrient sources. [ABSTRACT FROM AUTHOR]

Eucolaspis sp. "Hawke's Bay" (Chrysomelidae: Eumolpinae) is a pest that inflicts huge economic loss in many organic apple (Malus domestica Borkh.) orchards in New Zealand. The timing of control methods for this pest has been shown to be crucial for success. To aid in planning control programs, we studied threshold temperature and degree-days required for the development of Eucolaspis sp. "Hawke's Bay" pupae and modeled adult emergence in the field. Pupal development was observed at three constant temperatures. Pupae required 237.0 ± 21.67 degree-days above lower threshold temperature of 4.7°C ± 0.89°C to develop into adults. The emergence of adults was modeled with these thermal values and the model was tested for accuracy with field data. The model performed well with a precision of ± 4 d. The proposed phenology model has wide applicability in monitoring and planning pest control measures. [ABSTRACT FROM AUTHOR]

This study reports economic thresholds for the lettuce aphid Nasonovia ribisnigri (Mosley ), based exclusively on cosmetic damage, that is, presence or absence of aphids at harvest time. Field trials were conducted in La Poveda Experimental Farm, Madrid (Spain) during autumn (2004 and 2005) and spring (2005 and 2006). Plants were arranged in plots and just before the formation of lettuce hearts they were infested with different densities of N. ribisnigri. Two days later, half of each plot was treated with tau-fluvalinate (Klartan24AF) and the other half remained as an untreated control. Economic thresholds were obtained from nonlinear regressions calculated between the percentage of commercial plants at the end of the crop cycle for both, treated and untreated semiplots, and the different initial densities of N. ribisnigri per plant. Two criteria were used to consider a commercial lettuce plant: a conservative estimate (0 aphids/plant) and a lax one (<5 aphids/plant). Thus, an economic threshold was established for each season and critérium. The economic thresholds that were obtained with the most and least conservative criteria were in spring 0.06 and 0.12 aphids per plant, and in autumn 0.07 and 0.13 aphids per plant, respectively. These results show that to avoid cosmetic damage, insecticide sprays are required when a very low aphid density is detected in lettuce seedlings soon after transplant. [ABSTRACT FROM AUTHOR]

Phosphine gas, or hydrogen phosphide (PH3) is the most common insecticide applied to durable stored products worldwide and is routinely used in the United States for treatment of bulk-stored cereal grains and other durable stored products. Research from the late 1980s revealed low frequencies of resistance to various residual grain protectant insecticides and to phosphine in grain insect species collected in Oklahoma. The present work, which used the same previously established discriminating dose bioassays for phosphine toxicity as in the earlier study, evaluated adults of nine different populations of red flour beetle, Tribolium castaneum (Herbst), and five populations of lesser grain borer, Rhyzopertha dominica (F.) collected from different geographic locations in Oklahoma. One additional population for each species was a laboratory susceptible strain. Discriminating dose assays determined eight out of the nine T. castaneum populations, and all five populations of R. dominica, contained phosphine-resistant individuals, and highest resistance frequencies were 94 and 98%, respectively. Dose-response bioassays and logit analyses determined that LC99 values were ≈3 ppm for susceptible and 377 ppm for resistant T. castaneum, and ≈2 ppm for susceptible and 3,430 ppm for resistant R. dominica. The most resistant T. castaneum population was ll9-fold more resistant than the susceptible strain and the most resistant R. dominica population was over 1,500-fold more resistant. Results suggest a substantial increase in phosphine resistance in these major stored-wheat pests in the past 21 yr, and these levels of resistance to phosphine approach those reported for other stored-grain pest species in other countries. [ABSTRACT FROM AUTHOR]

Two systemic neonicotinoids, imidacloprid and thiamethoxam, are widely used for residual control of several insect pests in cotton (Gossypium spp. ),vegetables, and citrus (Citrus spp.). We evaluated their impact on six species of beneficial arthropods, including four parasitoid species—Aphytis melinus Debach, Gonatocerus ashmeadi Girault, Eretmocerus eremicus Rose & Zolnerowich, and Encarsia formosa Gahan—and two generalist predators—Geocoris punctipes (Say) and Onus insidiosus (Say)—in the laboratory by using a systemic uptake bioassay. Exposure to systemically treated leaves of both neonicotinoids had negative effects on adult survival in all four parasitoids, with higher potency against A. nwlinus as indicated by a low LC50. Mortality was also high for C. ashmeadi, E. eremicus, and E. formosa after exposure to both compounds but only after 48 h posttreatment. The two predators C. punctipes and O. insidiosus were variably susceptible to imidacloprid and thiamethoxam after 96-h exposure. However, toxicity to these predators may be related to their feeding on foliage and not just contact with surface residues. Our laboratory results contradict suggestions of little impact of these systemic neonicotinoids on parasitoids or predators but field studies will be needed to better quantify the levels of such impacts under natural conditions. [ABSTRACT FROM AUTHOR]

Several transgenic lines of soybean, Glycine max (L.) Merr., expressing a synthetic cry1A gene from Bacillus thuringiensis (Bt), were examined in replicated field trials in 2003-2007 for suppression of naturally occurring population densities of lepidopteran pests and the resultant crop injury that they caused. Bt soybean and negative controls (isogenic segregants and parental lines) were evaluated against velvetbean caterpillar, Anticarsia gemmatali.s (Hübner); soybean looper, Pseudoplusia includens (Walker); and green cloverworm, Hypena scabra (F.). Population densities of these lepidopteran species were essentially absent in each of the Bt soybean entries evaluated throughout the growing season in every year of the study compared with moderate (5-10 larvae per row-m) to large (20-30 larvae per row-m) peak population densities in the negative control soybean entries. These lepidopteran populations caused significant plant injury in the non-Bt soybean plots, ranging from 53% defoliation in 2003 to 17.5% in 2007, compared with <1.5% defoliation (mostly 0.0% defoliation) in the Bt soybean plots. When two or three foliar insecticides were applied in August or September, as lepidopteran populations approached or exceeded economic threshold levels, pest populations were suppressed and defoliation was minimal in the treated non-Bt entries similar to results in Bt soybean. Soybean 100-seed weights and harvested yields were similar between the Bt and non-Bt entries each year of this study. It seems that Bt transgenic soybean provides excellent season-long control of lepidopteran pests and have yields equal to the standard cultivars examined in this study. Once available to producers, this Bt technology has the potential to provide an effective insect pest management option similar to that being used in Bt cotton, Gossypium hirsutum L., and Bt corn, Zea mays L., and enhance the sustainability and profitability of soybean production in the southern region where lepidopteran pests cause annual economic losses to the crop. [ABSTRACT FROM AUTHOR]

Susceptibility to the Cry1Ac toxin from Bacillus thuringiensis in tobacco budworm, Heliothis virescens (F.) (Lepidoptera: Noctuidae), is usually measured by performing bioassays under laboratory conditions. Accurate comparison of Cry1Ac susceptibility among H. virescens samples conducted in different places is challenged by several important methodological aspects, especially if different insect artificial diets are used to perform bioassays. In this study, we compared Cry1Ac susceptibility of four different-origin H. virescens colonies when challenged with this toxin incorporated into four different insect artificial diets. Our data show that Cry1Ac susceptibility was lower in all the H. virescens colonies for one of the commercial diets (Bio-Serv). Bio-Serv diet was one of the least significantly consumed diets by larvae of the four different colonies, which indicates that insects encountered less Cry1Ac toxin due to lower consumption of diet. Larvae fed Bio-Serv diet also seemed to display slower Cry1Ac toxin activation compared with larvae fed any of the other three diets tested. In contrast, a wheat germ-soybean diet (ARS) was one of the most consumed diets by the four H. virescens colonies. The increased consumption of ARS diet probably led to the high level of Cry1Ac susceptibility observed in all the H. virescens colonies. Our data highlight the importance of using common diets and use a standard tobacco budworm colony when comparing Cry1Ac susceptibility between diverse H. virescens strains or across time. [ABSTRACT FROM AUTHOR]

The development, survival, and reproduction of Liposcelis paeta Pearman (Psocoptera: Liposcelididae), an important insect pest of stored products, were evaluated at nine constant temperatures (20-40°C). Few insects could complete the development or reproduce at 20 or 40°C. Between 22.5 and 37.5°C, the developmental period from egg to adult varied from 45.4 d at 22,5°C to 11.5 d at 37.5°C. The lower temperature developmental thresholds were estimated at 18.1-21.9°C, and the upper temperature thresholds were 40.4-42.0°C. The percentage of survival from egg to adult was 52.79% at 32.5°C and 18.79% at 22.5°C. After emergence, the adult had a short preoviposition period that ranged from 6.3 d at 22,5°C to 0.8 d at 37.5°C. L. paeta produced the most eggs at 27,5°C and the fewest at 37.5°C. The population reared at 32.5°C had the highest intrinsic rate of increase compared with the other temperatures. Based on our data, the optimal range of temperature for L. paeta population growth was 30-35°C. These data give us better understanding of L. paeta population dynamics, and they can be used to develop effective management strategies for this psocid. [ABSTRACT FROM AUTHOR]

The confused flour beetle, Tribolium confusum Jacquelin du Val (Coleoptera: Tenebrionidae) is a stored-product pest that contaminates a wide range of food products, from flour and cereals to spices. The insect reduces food quality and is responsible for large economic losses every year. Although several methods for detection of stored-product pests are common and widely used, they are time-consuming and expensive. Therefore, establishing molecular methods of detection of stored-product pests could provide a useful alternative method. We have undertaken attempts to establish methods of detection of T. confusum based on molecular biology techniques of standard and real-time polymerase chain reaction (PCR). Total DNA of T confusum and red flour beetle, Tribolium castaneum (Herbst) (Coleoptera: Tenebrionidae), used as a negative control, was isolated from insects and used as a template in standard and real-time PCR reactions. Specific primers have been designed on the basis of sequences of internal transcribed spacer (ITS) fragment of rDNA and subunit I of mitochondrial cytochrome oxidase of T confusum available in the GenBank database. Standard PCR reactions with primers specific to the ITS fragment proved to be reliable and sensitive. Real-time PCR reactions with primers specific for mitochondrial DNA are considered to serve as a supplemental detection method for quantitative assessment of the infestation level. [ABSTRACT FROM AUTHOR]

Results of planting date and insecticide efficacy experiments targeting Lissorhoptrus oryzophilus Kuschel (Coleoptera: Curculionidae) on rice, Oryza sativa L., in southeastern Texas between 2002 and 2007 were used to determine density-yield relationships as a function of planting date. Soil core samples were collected on two dates during main crop development to estimate immature L. oryzophilus populations followed by main and ratoon crop harvests. Analysis of covariance (ANCOVA) revealed that planting date did not affect the density-main crop yield relationship during most years and that these relationships varied substantially among years. For ratoon crop yield, an effect of main crop L. oryzophilus immature infestation was detected during some years, but the real effect of these populations on ratoon crop yield remains unclear. Using estimates of yield reduction per L. oryzophilus immature, economic injury levels were calculated. Main crop yields from treated plots and first soil core sample L. oryzophilus immature populations from untreated plots were significantly higher in plots planted at recommended dates than in plots planted earlier or later. This suggests that the presence of high populations of reproductive L. oryzophilus coincides with the period when rice fields planted at optimum dates are flooded. Results from this study reinforce the importance of managing L. oryzophilus populations when planting rice at recommended dates in southeastern Texas. [ABSTRACT FROM AUTHOR]

Phytophagous stink bugs (Hemiptera: Pentatomidae), including green stink bug [Acrosternun hilare (Say)], southern green stink bug [Nezara viridula (L.)], and brown stink bug [Easchistus servus (Say)], have become a serious production issue for southeastern U.S. cotton, Gossypium hirsutum L., growers. To investigate how different agronomic crops may affect stink bug damage and fiber quality in neighboring cotton fields, replicated 1.6-2.0-ha trials were planted with corn (Zea mays L.), peanut (Arachis hypogaea L.), and soybean [Glycine max (L.) Merr.] bordering a centrally located cotton plot (each of the four crops composed of ≈0.4 -0.5 ha per trial). Three trials were conducted in 2007 and three additional trials were conducted in 2008. Stink bug damage in the cotton plot was sampled weekly during weeks 3 through 6 of bloom at distances of 0.5, 5.3, 9.6, and 18.7 m from the adjacent crop. At the end of the year, representative lint samples at distances of 0.5, 9.6,18.7, and 31.8 m from each adjacent crop were mechanically harvested, ginned, and classed. Results show that boll damage, seedcotton yield, gin turnout, fiber color, and lint value were negatively affected when the cotton was located adjacent to peanut and soybean. Regardless of the adjacent crop, there were no differences among yield and fiber quality parameters comparing seedcotton obtained 18.7 m from the plot edge and samples obtained from the middle of the cotton plot (≈31.8 m from an adjacent crop). These data suggest that integrated pest management programs for the stink bug complex in cotton may include farmscape level planning and targeted interventions as opposed to a crop specific management approach. [ABSTRACT FROM AUTHOR]

Decision support systems have been developed for risk analysis and management of root-feeding white grubs (Coleoptera: Scarabaeidae: Melolonthinae) in Queensland, Australia, sugarcane (Saccharum spp.), based partly on manual inspection of soil samples. Acoustic technology was considered as a potential alternative to this laborious procedure. Field surveys were conducted to detect the major pests Dermolepida albohirtum (Waterhouse) near Mackay, and Antitrogus parvulus Britton near Bundaberg. Computer analyses were developed to identify distinctive scrapes and other sounds produced by D. albohirtum and Antitrogus species and to distinguish them from sounds of nondamaging white grubs (Rutelinae, Dynastinae), as well as from extraneous, wind-induced tapping signals. Procedures were considered for incorporating acoustic methods into surveys and sequential sampling plans. Digging up and inspecting sugarcane root systems requires 10-12 min per sample, but acoustic assessments can be obtained in 3-5 min, so labor and time could be reduced by beginning the surveys with acoustic sampling. In a typical survey conducted in a field with low population densities, sampling might terminate quickly after five negative acoustic samples, establishing a desired precision level of 0.25 but avoiding the effort of excavating and inspecting empty samples. With a high population density, sampling might terminate also if signals were detected in five samples, in which case it would be beneficial to excavate the samples and count the white grubs. In intermediate populations, it might be necessary to collect up to 20 samples to achieve desired precision, and acoustic methods could help determine which samples would be best to excavate. [ABSTRACT FROM AUTHOR]

The widespread use of insecticides is known to cause resurgence in Nilaparvata lugens (StåI) (Hemiptera: Delphacidae) populations, a serious insect pest of rice, Orzya sativa L., crops in Asia. The current study investigated insecticide-induced changes in protein, RNA, and DNA levels in the ovary and fat body of adult female N. lugens. Potted rice plants were sprayed with different concentrations of imidacloprid, triazophos, and detamethrin. The results showed that all three insecticides caused a significant increase in protein and RNA contents in the ovary and fat body of adult females developed from nymphs fed on treated plants compared with those from on untreated plants, although there was no significant effect on DNA content. In general, protein and RNA contents in both ovary and fat body increased linearly with insecticide concentrations or days after emergence (DAEs) when they were applied. There was a significant correlation between protein content and RNA content in both ovary and fat body. In addition, the relationship between ratios of RNA to protein in ovary and fat body of adult female N. lugens and insecticide concentrations showed a significant positive correlation for most DAEs of imidacloprid and several DAEs of triazophos and deltamethrin treatments. These findings suggest that RNA in both ovary and fat body was more sensitive to insecticides and that the insecticide-induced changes in RNA content in turn influence protein synthesis in ovary and fat body. Consistently, RNA-to-protein ratios in ovary and fat body were ≈0.42 in all treatments and controls. [ABSTRACT FROM AUTHOR]

Cotton, Gossypium hirsutum L., plants expressing Cry1Ac and Cry1F insecticidal crystal proteins of Bacillus thuringiensis Berliner (Bt) were evaluated against selected lepidopteran pests including fall armyworm, Spodoptera frugiperda (J. E. Smith), beet armyworm, Spodoptera exigua (Hübner), and soybean looper, Pseudoplusia includens (Walker). Studies were conducted in a range of environments, challenging various cotton tissue types from several varieties containing a combination of Cry1Ac and Cry1F proteins, In fresh tissue bioassays of mature leaves and squares (flower buds) and in artificial field infestations of white flowers, plants containing Cry1Ac:Cry1F significantly reduced levels of damage (leaf defoliation, bract feeding, penetrated squares and boils, and boll abscission) and induced significantly greater mortality (90-100%) of fall armyworm compared with that on non-Bt cotton plants. Plants containing Cry1Ac:Cry1F conferred high levels (100%) of soybean looper mortality and low levels (0.2%) of leaf defoliation compared with non-Bt cotton. Beet armyworm was relatively less sensitive to Cry1Ac:Cry1F cotton plants compared with fall armyworm and soybean looper. However, beet armyworm larval development was delayed 21 d after infestation (DAI), and ingestion of plant tissue was inhibited (14 and 21 DAI) on the Cry1Ac:Cry1F plants compared with that on non-Bt cotton plants. These results show Cry1Ac:Cry1F cotton varieties can be an effective component in a management program for these lepidopteran pest species. Differential susceptibility of fall armyworm, beet armyworm, and soybean looper larvae to Cry1Ac:Cry1F cotton reinforces the need to sample during plant development and respond with a foliar insecticide if local action thresholds are exceeded. [ABSTRACT FROM AUTHOR]

Effects on adult longevity, fecundity and fertility, as well as long-term effects on progeny were determined through oral exposure of Spodoptera littoralis (Boisduval) (Lepidoptera: Noctuidae) adults to azadirachtin and methoxyfenozide. Both compounds reduced adult longevity by 2.3 d at the higher concentrations tested, but no significant differences were observed between sexes. Fecundity and fertility were significantly affected for both insecticides, although this effect was only dose-dependent for azadirachtin. The progeny from adults treated with azadirachtin or methoxyfenozide were only affected in percentage of pupation of eggs that successfully hatched, but no effects were observed in adult emergence of individuals that successfully pupated for either insecticide. In the second part of this study, each sex was exposed separately to methoxyfenozide by topical application or ingestion. Adult fecundity was more affected when moths were treated by ingestion than when treated topically, with a mean number eggs laid per female of 343 ± 89 and 932 ± 79, respectively. Finally, azadirachtin applied to pepper plants showed a significant oviposition deterrence activity on S. littoralis adults. However, when fecundity was scored for one additional day in females that had been previously exposed to pepper, Capsicum annum L., plants treated with this insecticide, the number of eggs laid per female did not differ significantly from that of controls. The effects of azadirachtin and methoxyfenozide on S. littoralis suggest changes in population dynamics of this pest in crops treated with these insecticides. [ABSTRACT FROM AUTHOR]

The impact of trademarked and commercial products on settling of adults of the sweetpotato whitefly, Bemisia tabaci (Gennadius), was studied in the laboratory. A no-choice bioassay using leaf disks of tomato, Solanum esculentum L., was developed to evaluate the impact of concentration series of products on settling of B. tabaci adults. The concentration of each product that would reduce settling by 50% (SC50) was estimated for each product using standard probit analyses, and the values were compared with that of Ultra-Fine Oil, a paraffinic oil product that is known to reduce settling of whitefly adults. Twenty-two trademarked products and 42 other products were evaluated in the laboratory bioassay. Based upon comparisons of fiducial limits of the respective SC50 values, Dawn detergent and E-RASE jojoba oil were the only trademarked products that were as effective as Ultra-Fine Oil in reducing settling of B. tabaci adults. Of the nontrademarked products, 25 were similar to Ultra-Fine Oil, although cedar, geranium, ginger, Hamlin (citrus), patchouli, olive and wintergreen oils, as well as citronellal and limonene, had ratios of respective SC50 values with that of Ultra-Fine Oil of ≈1.5 or less. Combinations of limonene and citronellal with either olive oil or Ultra-Fine Oil were 15 and 30 times, respectively, more effective than Ultra-Fine Oil alone. Candidate products and combinations of products were further evaluated on tomato seedlings in no-choice screenhouse trials for effects on oviposition and on transmission of Tomato yellow leaf curl virus (family Geminiviridae, genus Begomovirus, TYLCV) by B. tabaci. Ultra-Fine Oil and olive oil reduced oviposition and transmission of TYLCV in the screenhouse trials. Ginger oil and limonene reduced oviposition in at least one screenhouse trial but did reduce transmission of TYLCV. The laboratory bioassay provided a rapid and relatively easy method to compare products for reducing settling of B. tabaci adults. Even though the reduced settling indicated in the laboratory bioassays was not always reflected in reduced oviposition or TYLCV transmission in the screenhouse trials, the bioassay was useful in rapidly identifying products that reduce settling and that could be investigated further. [ABSTRACT FROM AUTHOR]

ABSTRACT To recommend new pest management tactics and strategies to farmers and policy makers, economic entomologists must evaluate the economics of biologically reasonable approaches. We collected data to determine how frequently these economic evaluations occur. We discovered from our survey of entomological journals representing the discipline of economic entomology that <1% of research papers published since 1972 include economic evaluations of pest management tactics. At least 85% of these analyses were performed by entomologists and not economists. Much of the research on economic evaluations is performed without special funds granted by agencies separate from the authors' institutions. In the United States, USDA competitive grants supported 20% of the economic evaluations published since 2000. However, only ≈12% of the projects funded since 2000 by three sections of the USDA (Crops at Risk, Risk Avoidance and Mitigation Program, and Pest Management Alternatives Program) resulted in publications concerning economic evaluations. If the purpose of economic entomology is to ultimately determine the value of different kinds of tactics, the discipline may need to take steps to enhance the research that supports these evaluations. [ABSTRACT FROM AUTHOR]

Liquid baits were evaluated for control of the Argentine ant, Linepithema humile (Mayr) (Hymenoptera: Formicidae), and associated mealybug and soft scale pests in California vineyards. In 2003, liquid baits with small doses of imidacloprid, boric acid, or thiamethoxam dissolved in 25% sucrose water resulted in lower ant and mealybug densities and fruit damage, compared with an untreated control. Similar treatments in a soft scale-infested vineyard showed only a reduction of ant density and fruit infestation in only the boric acid and thiamethoxam treatments. In 2004, commercial and noncommercial formulations of liquid baits reduced ant densities in three separate trials, but they had inconsistent effects on mealybug densities and fruit infestation; granular protein bait had no effect. Using large plots and commercial application methodologies, liquid bait deployed in June resulted in lower ant density and fruit infestation, but it had no effect on mealybug density. Across all trials, liquid bait treatments resulted in lower ant density (12 of 14 trials) and fruit damage (11 of 14 sites),presenting the first report of liquid baits applied using commercial methodologies that resulted in a reduction of ants and their associated hemipteran crop damage. For commercialization of liquid baits, we showed that any of the tested insecticides can suppress Argentine ants when properly delivered in the crop system. For imidacloprid, bait dispensers must be protected from sunlight to reduce photodegradation. Results suggest that incomplete ant suppression can suppress mealybug densities. However, after ant populations are suppressed, there may be a longer period before hemipteran populations are effectively suppressed. Therefore, liquid baits should be considered part of a multiseason program rather than a direct, in-season control of hemipteran pest populations. [ABSTRACT FROM AUTHOR]

A 10-wk study of the avocado seed-feeding moth Stenoma catenifer Walsingham (Lepidoptera: Elachistidae), was conducted in a commercial 'Hass' avocado (Persea americana Miller [Lauraceae]) orchard in Guatemala. Up to 45% of fruit in the orchard were damaged by larval S. catenifer. Larval-to-adult survivorship for 1,881 S. catenifer larvae in Hass fruit was 37%, and adult sex ratio was 51% female. Four species of larval parasitoid were reared from field-collected S. catenifer larvae. The most common parasitoid reared was a gregarious Apanteles sp., which parasitized 53% of larvae and produced on average eight to nine cocoons per host. Apanteles sp. sex ratio was 47% female and 87% of parasitoids emerged successfully from cocoons. Apanteles sp. longevity was ≈1.5 d in the absence of food, and when provisioned with honey, parasitoids survived for 5-7 d. The mean number of cocoons produced by Apanteles sp. per host, and larval parasitism rates were not significantly affected by the number of S. catenifer larvae inhabiting seeds. Oviposition studies conducted with S. catenifer in the laboratory indicated that this moth lays significantly more eggs on the branch to which the fruit pedicel is attached than on avocado fruit. When given a choice between Hass and non-Hass avocados, S. catenifer lays up to 2.69 times more eggs on Hass. [ABSTRACT FROM AUTHOR]

Cotesiaflavipes (Cameron) (Hymenoptera: Braconidae) is used as a classical biological control agent against Chilo partellus (Swinhoe) (Lepidoptera: Crambidae), a serious exotic pest of cereal crops in eastern and southern Africa. This parasitoid has been introduced into several African countries for the control of C. partellus in maize, Zea mays L., and sorghum, Sorghum bicolor (L.), but it has never been released in Ethiopia. It is hypothesized that it spread into Ethiopia from populations released in Kenya and Somalia to become the predominant parasitoid of C. partellus in maize and sorghum fields of the country. In recent surveys conducted in Ethiopia, C.flavipes was recovered from C. partellus in sugarcane, Saccharum L. spp. hybrids, at a site >2,000 km from the nearest known release sites in Kenya and Somalia. These findings question published hypotheses that estimate the dispersal rate of C. flavipes to be 60 km per year in Africa, and they suggest that since its release in Africa this parasitoid has developed strains adapted to searching particular host plants infested by particular stem borers. The anomalies between our results and previous reports evoked the hypothesis that C.flavipes in Ethiopian sugarcane might be a different strain. To test this hypothesis, we compared partial COI gene sequences of C. flavipes collected from sugarcane in Ethiopia and those of specimens from other African countries to determine the origin of the Ethiopian population. In addition, COI sequences were obtained for C. flavipes from other continents. The C. flavipes population established in Ethiopian sugarcane is most closely related to the populations released against C. partellus in maize in other parts of Africa, which were derived from the original population imported from Pakistan. The dispersal rate of the parasitoid was estimated to be >200 km per year. [ABSTRACT FROM AUTHOR]

Cavity-nesting alfalfa leafcutting bees, Megachile rotundata (F.) (Hymenoptera: Megachilidae), are excellent pollinators of alfalfa, Medicago savita L., for seed production. In commercial settings, artificial cavities are placed in field domiciles for nesting and, thereby, bee populations are sustained for future use. For this study, cells from leafcutting bee nests were collected in late summer from commercial seed fields. Over 3 yr (2003-2005), 39 samples in total of °°1,000 cells each were taken from several northwestern U.S. states and from Manitoba, Canada. X-radiography of 500 cells from each sample was used to identify "pollen balls" (i.e., cells in which the pollen-nectar provision remained, but the egg or larva, if present, was not detectable on an x-radiograph). Most U.S. samples seemed to have higher proportions of pollen ball cells than Manitoba samples. Pollen ball cells were dissected to determine the moisture condition of the mass provision and true contents of each cell. Most pollen ball cells from Manitoba samples contained fungus, the frequency of which was positively correlated with cool, wet weather. In the United States, most pollen ball cells had moist provisions, and many of them lacked young brood. Correlation analysis revealed that pollen ball cells occurred in greater proportions in fields with more hot days (above 38°C). Broodless pollen ball cells occurred in greater proportions under cool conditions, but dead small larvae (second-third instars) seemed to occur in greater proportions under hot conditions. Pollen ball cells with unhatched eggs and first instars (in the chorion) occurred in lesser proportions under hot conditions. [ABSTRACT FROM AUTHOR]

To replace deceased colonies or to increase the colony numbers, beekeepers often purchase honey bees, Apis mellifera L., in a package, which is composed of 909-1,364 g (2-3 lb) of worker bees and a mated queen. Packages are typically produced in warm regions of the United States in spring and shipped throughout the United States to replace colonies that perished during winter. Although the package bee industry is effective in replacing colonies lost in winter, packages also can be an effective means of dispersing diseases, parasites, and undesirable stock to beekeepers throughout the United States. To evaluate the quality of packages, we examined 48 packages representing six lines of bees purchased in the spring 2006. We estimated levels of the parasitic mite Varroa destructor Anderson & Trueman and the percentage of drone (male) honey bees received in packages. We surveyed for presence of the tracheal honey bee mite, Acarapi.s woodi (Rennie), and a microsporidian parasite, Nosema spp., in the shipped bees. We found significant differences in both the mean Varroa mite perbee ratios (0.004-0.054) and the average percentage of drones (0.04-5.1%) in packages from different producers. We found significant differences in the number of Nosema-infected packages (0.0-75.0%) among the six lines. No packages contained detectable levels of A. woodi. Considering the observed variability among honey bee packages, beekeepers should be aware of the potential for pest and disease infestations and high drone levels in packages. [ABSTRACT FROM AUTHOR]

Chalkbrood, a fungal disease in bees, is caused by several species of Ascosphaera. A. aggregata is a major mortality factor in populations of the alfalfa leafcutting bee, Megachile rotundata (F.) (Hymenoptera: Megachilidae) used in commercial alfalfa seed production. Four formulated fungicides, Benlate 50 WP, Captan, Orbit, and Rovral 50 WP were tested in the laboratory for efficacy against hyphal growth of A. aggregata cultures. The same fungicides, with the addition of Rovral 4 F, were tested for their effects on incidence of chalkbrood disease, and toxicity to M. rotundata larvae. Benlate, Rovral 50 WP, and Rovral 4 F reduced incidence of chalkbrood with minimal mortality on larval bees. Benlate and Rovral 50 WP also reduced hyphal growth. Orbit was effective in reducing hyphal growth, but it did not reduce incidence of chalkbrood and was toxic to bee larvae. Captan was not effective in reducing hyphal growth or chalkbrood incidence, and it was toxic to bee larvae. Fungicides that reduce incidence of chalkbrood and larval mortality in this laboratory study are candidates for further study for chalkbrood control. [ABSTRACT FROM AUTHOR]

The utility of USDA~developed Russian and varroa sensitive hygiene (VSH) honey bees, Apis mellifera L. (Hymenoptera:Apidae), was compared with that of locally produced, cornmercial Italian bees during 2004-2006 in beekeeping operations in Alabama, USA. Infestations of varroa mites, Varroa destructor Anderson & Truman (Acari: Varroidae), were measured twice each year, and colonies that reached established economic treatment thresholds (one mite per 100 adult bees in late winter; 5-10 mites per 100 adult bees in late summer) were treated with acaricides. Infestations of tracheal mites, Acarapis woodi (Rennie) (Acari: Tarsonemidae), were measured autumn and compared with a treatment threshold of 20% mite prevalence. Honey production was measured in 2005 and 2006 for colonies that retained original test queens. Throughout the three seasons of measurement, resistant stocks required less treatment against parasitic mites than the Italian stock. The total percentages of colonies needing treatment against varroa mites were 12% of VSH, 24% of Russian, and 40% of Italian. The total percentages requiring treatment against tracheal mites were 1% of Russian, 8% of VSH and 12% of Italian. The average honey yield of Russian and VSH colonies was comparable with that of Italian colonies each year. Beekeepers did not report any significant behavioral problems with the resistant stacks, These stocks thus have good potential for use in nonmigratory beekeeping operations in the southeastern United States. [ABSTRACT FROM AUTHOR]

During orchard pollination studies in California, we observed dramatic changes in nesting and foraging behavior of Osmia lignaria Say (Hyrnenoptera: Megachilidae) after sprays with tank mixtures containing fungicides. A characteristic pattern of postspray events observed includes erratic behavior and interrupted foraging and nesting activity for several days. In an effort to determine whether fungicidal sprays were disruptive to bee foraging and thus to pollination, we exposed O. lignaria females nesting in field cages planted with lacy scorpionweed, Phacelia tanacetifolia Benth (Hydrophyllaceae), to selected spray mixtures normally encountered in California orchard production systems: iprodione (Rovral), propiconazole (Orbit), benornyl (Benlate), and captan (Captan 50 WP); the surfactant Dyne-Amic, alone and mixed with Rovral; and the tank mixture 1DB (Rovral + Dyne-Amic + the foliar fertilizer Bayfolan Plus). An additional cage sprayed with an equal volume of water acted as control, and a cage sprayed with the insecticide dimethoate as a toxic standard. For each female O. lignaria, we recorded time spent inside the nest depositing pollen-nectar loads, foraging time, cell production rate, and survival. All females in the dimethoate treatment died postspray + 1 d. Before death, some of these females behaved similarly to our previous orchard observations. A high proportion of females in the 1DB cage were inactive for a few hours before resuming normal foraging and nesting activity. No lethal or behavioral effects were found for any of the other compounds or mixtures tested. Our results indicate that the fungicide applications that we tested are compatible with the use of O. lignaria as an orchard pollinator. [ABSTRACT FROM AUTHOR]

The genetic basis of spinosad resistance was investigated in the western flower thrips, Frankliniella occidentalis (Pergande) (Thysanoptera: Thripidae). The resistant strain, selected in the laboratory for spinosad resistance from a pool of thrips populations collected in Almeria (southeastern Spain), showed a very high resistance to spinosad (356,547-fold based on LC50 values) compared with the laboratory susceptible strain. Mortality data from reciprocal crosses of resistant and susceptible thrips indicated that resistance was autosomal and not influenced by maternal effects. Analysis of probit lines from the parental strains and reciprocal crosses showed that resistance was expressed as an almost completely recessive trait. To determine the number of genes involved, a direct test of monogenic inheritance based on the backcrosses suggested that resistance to spinosad was probably controlled by one locus. Another approach, which was based on phenotypic variances, showed that nE, or the minimum number of freely segregating genetic factors for the resistant strain, equaled 0.59. [ABSTRACT FROM AUTHOR]

A field study was conducted in 2003 and 2004 at the Center for Environmental Farming Systems in Goldsboro, NC, to evaluate the effectiveness of a commercially available beneficial insect habitat in decreasing pest caterpillar populations in organically managed tomato, Lycopersicon esculentum Mill., plots. Six pairs of tomato plots were established and a commercial beneficial insect habitat seed mix (Peaceful Valley's Good Bug Blend) transplanted around the perimeter of treatment plots, whereas a brown-top millet, Brachiaria ramose (L.) Stapf., border was planted around control plots. Egg predation, egg parasitism by trichogrammatid wasps, and larval parasitism by braconid wasps was monitored throughout the growing season to determine whether habitat increased their activity. In both years of this study, the density of Helicoverpa zea (Boddie) and Manduca spp. eggs was not significantly different between treatment and control plots. Although parasitism was the most important component of egg mortality (19–49%), parasitism was not significantly different between habitat types. Identifiable predation was a minor component (3–9%) of egg fate; it is possible that unidentified predation may be part of the ≈35–52% of eggs that met unknown fates. Larval parasitism levels ranged from ≈10 to 90% but was not significantly influenced by the presence of beneficial insect habitat in either year of the study. These results demonstrate that natural enemy activity in organic tomatoes was not amplified, and pest populations were not reduced by the presence of a commercially available beneficial insect habitat. [ABSTRACT FROM AUTHOR]

The impact of a zoophytogenous, insect-free artificial diet on the developmental rate, life history parameters, and fertility was examined over 11 consecutive generations for domesticated Perillus bioculatus (F.) (Heteroptera: Pentatomidae). This study showed that when fed an insect-free artificial diet during both the nymphal and adult stages, developmental times were prolonged, and the net reproductive rates (R0) and the intrinsic rates of increase (rm) were significantly lower than when fed larval Trichoplusia ni at both nymphal and adult stages. Moreover, the cost to rear P. bioculatus on the artificial diet approached 1.1 times the cost of rearing P. bioculatus on natural prey. These results demonstrate the effectiveness and potential cost-savings of the zoophytogenous artificial diet for rearing a beneficial pentatomid. [ABSTRACT FROM AUTHOR]

A correction to the article "Reviewers for Journal of Economic Entomology" that was published in the September 2014-September 2015 issue is presented.