Adult Emergence Period Research Articles

Gamma Radiation Sensitivity of Different Stages of Saw-Toothed Grain Beetle Oryzaephilus Surinamensis L. (Coleoptera: Silvanidae)

Gamma Radiation Sensitivity of Different Stages of Saw-Toothed Grain BeetleOryzaephilus SurinamensisL. (Coleoptera: Silvanidae)The effect of gamma irradiation on different developmental stages ofOryzaephilus surinamensisL., was investigated. Results showed that a required dose to prevent larval emergence from irradiated 1-2-days-old eggs was 60 Gray (Gy), and 350 Gy was required to prevent adult emergence from 15-days-old larvae. Also the required dose of radiation to prevent adult emergence from irradiated 5-days-old pupa was 700 Gy. The dose of 200 Gy caused 100% mortality of irradiated adults 28 days after treatment. In addition, the effect of gamma rays was studied on the developmental stage period of each irradiated stage till adult emergence. The results revealed that there was a dose-dependent increase of the developmental periods. The growth index of adults was significantly decreased with increasing dose of radiation administered to eggs, larvae and pupae. It is recommended that doses between 600 and 700 Gy should be used to control population growth ofO. surinamensiswhen targeting pupae and adults present in stored products.

Identification of quantitative trait loci for bruchid (Callosobruchus maculatus) resistance in black gram [Vigna mungo (L.) Hepper

An inter-subspecific mapping population was generated by crossing V. mungo var. mungo (cv. TU 94-2, bruchid susceptible) and V. mungo var. silvestris (bruchid resistant). About 37.8% of the bruchid completed their lifecycle on seeds of V. mungo var. silvestris compared with 100% on the susceptible variety TU 94-2. The total developmental period of C. maculatus on Vigna mungo var. silvestris was considerably extended (88 days as compared with 34 days on TU 94-2). A genetic linkage map constructed using recombinant inbred lines (RILs) in F9 generation with 428 markers [86 random amplified polymorphic DNA (RAPD), 47 simple sequence repeat (SSR), 41 inter-SSR (ISSR), 254 amplified fragment length polymorphism (AFLP)] was used for QTL detection. One hundred four individuals were used for detection of QTLs associated with bruchid resistance. The RILs exhibited a high level of variation in percentage adult emergence (0–100%) and developmental period (0–105 days). Two QTLs, Cmrae1.1 and Cmrae1.2, were identified for percentage adult emergence, on linkage group (LG) 3 and 4, respectively. For developmental period, six QTLs were identified, with two QTLs (Cmrdp1.1 and Cmrdp1.2) on LG 1, three QTLs (Cmrdp1.3, Cmrdp1.4, and Cmrdp1.5) on LG 2, and one QTL (Cmrdp1.6) on LG 10.

Some Regularities in Long-term Dynamics of Temporal Dispersion ofPleuroptya Ruralison common Nettle and its ParasitoidMacrocentrus grandiiin Lithuania

Seasonal adaptations of insects to climate conditions are always a combination of their responses to a great variety of environmental stimuli. Our investigations deal with some aspects of the long-term emergence period in phytophagous as well as entomophagous insects in Lithuania. During the investigation carried out in Lithuania from 1982 to 2004 the emergence season of adult Pleuroptya ruralis and its primary parasitoid Macrocentrus grandii was recorded between June and August. The beginning of adult emergence of P. ruralis has a negative correlation with spring temperature. The peak of P. ruralis adult emergence and values of the M. grandii adult emergence period have a negative correlation with June temperature. A tendency for an earlier peak emergence period has been recorded. It may be linked with a rise in annual, spring and summer temperatures in Lithuania.

Uso de Pós de Origem Vegetal no Controle de Acanthoscelides obtectus Say (Coleoptera: Bruchidae) em Grãos de Feijoeiro

The effects of eleven vegetable powders applied in bean grains were evaluated on the biology of Acanthoscelides obtectus Say. The amount of 0.3g of powders mixed to 10g of grains of bean genotype IAC – Carioca was placed into plastic boxes with four couples of bean weevils during a 7-day period. Twenty five days after infestation, we started recording the oviposition and the number of emerged adults in each treatment. At the end of the adult emergence period, the dry weight of adults, the weight of consumed grains and period of development (egg-adult) were evaluated. The powders of Baccharis trimera Less., Mentha pulegium L. and Coriandrum sativum L. reduced the oviposition of A. obtectus, but do not affect the development of bean weevil larvae. The highest oviposition was obtained with bean grains mixed to powders of Leonurus sibiricus L.. The lowest weight of A. obtectus adults was obtained from bean grains treated with Azadirachta indica A. Juss. possibly due to the occurrence of feeding deterrence to A. obtectus larvae.

Reproductive development and seasonal activity of two Korean native Coprini species (Coleoptera: Scarabaeidae)

Seasonal activity of the native dung beetles, Copris ochus (Motschulsky) and Copris tripartitus Waterhouse, was studied in Jeju Island, Korea. Reproductive condition and breeding cycles of adult females were determined using physiological age-grading techniques to assess the proportions of newly emerged, nulliparous and parous beetles, and those resorbing oocytes. C. ochus appears to be univoltine. Its main period of adult emergence occurs in summer rather than in spring (March–May), as was previously thought. The female population consisted of the complete range of reproductive age classes in August–September. C. tripartitus also appears to be univoltine. However, this species has two adult activity periods: a peak activity in spring when most oviposition occurs, and another in autumn when the new generation emerges. With the onset of winter, C. tripartitus adults cease reproductive development and females over winter in a nulliparous stage.

Juvenile hormone acid methyl transferase is a key regulatory enzyme for juvenile hormone synthesis in the Eri silkworm, Samia cynthica ricini

During the period of adult emergence in the Eri silkworm, Samia cynthia ricini, the corpora allata (CA) are apparently reactivated in females, but not males. This creates a significant sexual dimorphism in juvenile hormone (JH) synthesis by CA. To determine the underlying molecular mechanisms in this process, we cloned cDNAs of two enzymes involved in the JH synthesis pathway: 3-hydroxy-3-methylglutaryl CoA reductase (HMGR) and juvenile hormone acid methyl transferase (JHAMT). Both Samcri-HMGR and -JHAMT mRNAs were detected in CA almost exclusively. However, their expression patterns were different from each other. During the period of adult emergence, Samcri-HMGR was expressed in CA at a constantly high level suggesting it plays little role for the regulation of JH synthesis. In contrast, the patterns of both Samcri-JHAMT mRNA level and enzyme activity were closely correlated with the patterns of JH synthesis, CA reactivation, and sexual dimorphism of JH synthesis. In addition, JHAMT mRNA levels were paralleled JH synthesis in the fifth-instar larvae of S. cynthia ricini and the pharate adults of the silkworm Bombyx mori. We infer from these results that JHAMT is a key regulatory enzyme for JH synthesis in the Eri silkworm.

Seasonal Occurrence and Soil Distribution of the Lesser Chestnut Weevil, Curculio sayi (Coleoptera: Curculionidae) in Mid-Missouri

Abstract The seasonal emergence periods from the soil of adult lesser chestnut weevil, Curculio sayi (Gyllenhal), was assessed for three years at a site in mid-Missouri using wire cone emergence traps. Two additional trap types, Circle and pyramid, were used to assess the timing of adult movement into the trees. The trap data indicated there were two distinct adult emergence periods, the first occurring in early-May and the second beginning late-August. This is in contrast to previous studies that have reported C. sayi as having only one seasonal emergence period (which occurs in the spring). Our study also examined the underground development of C. sayi. The data showed that, after leaving the chestnut, most larvae burrow to a soil depth of 7.5–15 cm where they remain for at least 19 mo, and that the weevils have an overall life cycle (egg hatch to adult emergence) of about 20–21 mo.

Biodiversity and adult emergence periods of mayflies (Ephemeroptera) inhabiting Candle Lake, SK

Biodiversity and adult emergence periods of mayflies (Ephemeroptera) inhabiting Candle Lake, SK

Life history and emergence patterns of stonefly species in mountain streams of the Futaleufú basin, Patagonia (Argentina)

The temporal dynamics in density, life histories, and emergence patterns were described for the first time for five Plecoptera species in tributaries of the Futaleufu River in Patagonia, Argentina. Benthic samples and adult collections were made in five low order Nothofagus forested streams. Four species of Gripopterygidae; Aubertoperla illiesi, Notoperlopsis femina, Antarctoperla michaelseni and Senzilloides panguipulli had simple, highly synchronized univoltine life histories. The austroperlid Klapopteryx kuscheli takes more than two years to develop. Emergence periods of most of the species were concentrated in late spring and summer (October to February), which suggests seasonal and synchronized life histories. Most N. femina adults were collected in mid spring indicating this species emerged first, whereas S. panguipulli emerged last from January to April. Aubertoperla illiesi showed a slightly delayed emergence at the high elevation site (La Hoya Stream) when compared to a piedmont stream, suggesting that temperature was an important control. Although we were unable to describe the life history of Limnoperla jaffueli (Gripopterygidae) its adult emergence period was November to January. Life histories of Plecoptera species in the studied streams seem to have a high degree of seasonality at least at this latitude, and are possibly determined by predictable temperature patterns and discharge regimes. This first contribution on the life histories of Plecoptera species helps us to better understand the dynamics and functioning of pristine but fragile aquatic environments in Patagonia.

Biochemical and molecular characterization of allatotropin and allatostatin from the Eri silkworm, Samia cynthia ricini

In a previous study, allatotropic and allatostatic activities were observed in brain extract from the Eri silkworm, Samia cynthia ricini ( Samcri) [Li, S., Jiang, R.-J., Cao, M.-X., 2002b. Allatotropic and allatostatic activities in brain extracts of the Eri silkworm, S. cynthia ricini, and the effects of Manduca sexta allatotropin and M. sexta allatostatin on juvenile hormone in vitro. Physiol. Entomol. 27, 322–329]. In the present study, the HPLC purified Samcri-allatotropin (AT) and -allatostatin (AST) factors were shown to have the same retention time as those of M. sexta ( Manse)-AT and -AST, respectively. Moreover, the amino acid sequences of mature Samcri-AT and -AST deduced from their encoding cDNAs are identical to the Manse-AT and -AST amino acid sequences. Both Samcri-AT and -AST genes were expressed in brain, nerve cord, and midgut, with Samcri-AT also detected in gonads and epidermis, suggesting their pleiotropic physiological functions. The expression levels of Samcri-AT and -AST genes correlated well with the allatoregulatory activities during the period of adult emergence indicating the two peptides tightly control JH synthesis, in a contradictive and cooperative manner. Our biochemical and molecular data of Samcri-AT and -AST and other studies demonstrate that these two peptides regulate JH synthesis by corpora allata in Lepidoptera and have pleiotropic physiological effects.

Seasonal phenology of Bactrocera minax (Diptera: Tephritidae) in western Bhutan.

The Chinese citrus fruit fly, Bactrocera (Tetradacus) minax (Enderlein), is one of the major citrus pests in Bhutan and can cause >50% mandarin (Citrus reticulata Blanco) fruit drop. As part of the development of a management strategy for the fly in mandarin orchards, population monitoring and experimental manipulations were carried out to determine: (i) adult emergence period; (ii) adult phenology patterns; (iii) period of crop susceptibility; and (iv) period from fruit drop to pupation. In western Bhutan, adult flies emerge from the overwintering pupal stage in late April/early May. Most flies are mature by the end of May and it is inferred that mating occurs at this time: from the beginning of June males rapidly disappear from the population and by mid- to late June are rare or absent from traps. Mature females are present in the mandarin crop at the beginning of June, but very little oviposition occurs until mid-June, while most damage has occurred by mid-July. Initiation of oviposition into mandarins is almost certainly linked to crop phenology. Adult flies disappear from the orchard system during August. After fruit drop, larvae were recorded leaving the fruit to pupate within 13 days. The use of early to mid-season protein bait sprays and/or targeted use of systemic insecticides during the one month oviposition period, plus the removal of fallen fruit once every 10 days, are recommended as control strategies.

Seasonal decline of body mass in adults of the wood-dwelling caddisfly Lype phaeopa (Psychomyiidae)

Larvae of the psychomyiid caddisfly Lype phaeopa (Stephens 1836) were reared under close to outdoor temperature conditions to investigate the seasonal fluc- tuations in body masses of emergent adults. The adult emergence period lasted from late February until late September, with two emergence peaks of males (March and August) and one for females (September). Females were always larger than males, illustrating a strong sexual size dimorphism. Decreasing body mass of emergent adults coincided with increasing temperature during the seasons until the end of the emer- gence period. Both sexes showed a significant relationship between body mass and wing length, which allowed me to estimate the loss of female body mass due to oviposition (55.7% ± 4.9). Egg size remained constant throughout the study (ovoid shape, mean length 216 µm, width 186 µm) but number of eggs decreased. The results imply that increasing temperature could be responsible for the decline in size and body mass of emergent adults (both sexes). A reason for this size reduction could be a constant growth rate (biomass increment) but an accelerated developmental rate induced by increasing tem- perature.

Diapause Development in the Blueberry MaggotRhagoletis mendax(Diptera: Tephritidae)

Pupal diapause in the blueberry maggot was studied to characterize the relationship between temperature and development during different phases of diapause and determine the traits responsible for the late adult emergence period in some populations present in blueberry fields in southern New Jersey. Pupae in the refractory phase of diapause were exposed to 1, 4, or 7°C for 45, 90, or 135 d, and in a separate experiment, to 11 or 15°C for similar periods of time, to determine temperature thresholds and rates of diapause development at constant temperature. Results showed that pupae took much longer to reach the activated phase of diapause when exposed to 1°C than 4 or 7°C and were able to reach the activated phase when exposed to up to 15°C. In the range of 4–15°C, diapause development was largely independent from temperature. Pupae in the activated phase of diapause were exposed to 7, 15, 20, 25, 30, 25:35 (12:12 h), and 35°C for 10 d. There was a linear increase in the development rate in the range of 7–30°C, and the development rate was similar at 30, 25:35 (12:12 h), and 35°C. The proportion of pupae reaching the activated phase of diapause from August to February in a normal early population and from October to February in a late population was compared by keeping pupae in the refractory phase outdoors in a screenhouse and bringing samples to 20°C monthly. Data showed that pupae of both early and late populations reached the activated phase from October to January. The duration of the activated phase of diapause in pupae of early and late populations kept at 20°C after exposure to cold was compared by measuring changes in their respiration rates. Results showed that the activated phase lasted 10–20 d in the early population versus 60–70 d in the late population. In the blueberry maggot, and possibly in other Rhagoletis species, adaptation of the adult emergence period to the fruiting period of different host plants seems to be mediated by changes in the duration of the activated phase of diapause.

Effects of sublethal doses of beta-cyfluthrin on mutant Drosophila melanogaster (Diptera: Drosophilidae)

Laboratory experiment was conducted to examine sublethal effects of beta-cyfluthrin (Bulldock® 025 SC) on the sepia mutant of Drosophila melanogaster at a temperature of 25±0.5°C, 50±5% relative humidity and a photoperiod of 16 : 8 (light : dark) hours. Males and females were exposed separately to beta-cyfluthrin (one tenth of the calculated LC50 value) mixed in the diet for 24, 48 and 72 h. Fecundity, hatchability, pupation, adult emergence, larval, pupal and total developmental periods were evaluated in the F1 generation after various cross combinations. A reduction in fecundity, egg hatching, number of larvae, pupae, adults and prolongation of larval, pupal and total developmental periods was observed. A significant reduction (p<0.05) in fecundity was observed only on the treated diet after treatment of both the sexes. Maximum effects were observed after 72 h treatment followed by 48 and 24 h. Males were found to be more susceptible to beta-cyfluthrin as compared to the females.

Efficacy of Wing Versus Delta Traps for Predicting Infestation Levels of Four Generations of the Nantucket Pine Tip Moth (Lepidoptera: Tortricidae) in the Southern United States

Abstract The use of pheromone trap catches to reliably predict damage by the Nantucket pine tip moth, Rhyacionia frustrana (Comstock), in loblolly pine (Pinus taeda L.) plantations would provide forest managers with a valuable integrated pest management tool. At 17 sites throughout four states in the southern United States, in areas where R. frustrana has four annual generations, adult moths were monitored throughout the year (2002) using two types of pheromone traps, and subsequent infestation levels were determined for each tip moth generation. Cumulative wing trap catch tallies up to published spray dates for three of four adult emergence periods were highly predictive of top whorl damage during the subsequent generation using linear regression models. Multiple linear regression that included initial average tree height as a covariate did not significantly improve model efficacy. Cumulative delta trap catch tallies up to the spray date were not predictive of subsequent damage levels for any tip moth ge...

Emergence of adult northern and western corn rootworms (Coleoptera: Chrysomelidae) following reduced soil insecticide applications.

A 3-yr investigation was conducted in commercial corn, Zea mays (L.), fields in eastern South Dakota to determine how reduced application rates of planting-time soil insecticides would influence temporal emergence patterns and survival of northern and western corn rootworms, Diabrotica barberi Smith and Lawrence, and D. virgifera virgifera LeConte, respectively. Beetle emergence was monitored at 2-d intervals throughout the entire adult emergence period of three growing seasons from corn plots treated with planting-time applications of labeled (1X) and reduced (0.5 and 0.75X) application rates of terbufos, tefluthrin, and chlorethoxyfos. No consistent insecticide- or rate-related impacts on mean total emergence per trap were recorded for any of the compounds investigated. However, terbufos applications resulted in a 52% reduction in the number of beetles captured per trap, 53% reduction in maximum rate of adult emergence, and a 59% reduction in overall rate of emergence over time for male D. virgifera during 1994. Terbufos also significantly extended the time required for emergence to peak and linear emergence of female D. virgifera to end in 1994. Tefluthrin applications delayed onset, end, and time of maximum emergence of female D. barberi by 9.9, 14.1, and 12 d, respectively, during 1993. Tefluthrin also reduced emergence rates over time for male (38%) and female (46%) D. barberi during 1994. Overall, application rate was inconsequential regarding total emergence, seasonal emergence pattern, or level of plant protection provided for all insecticides we tested in this 3-yr investigation. Our findings demonstrate that, if properly applied, the reduced application rates used in this study provide adequate root protection and will not significantly impact the biology of these pest species.

Efficacy of ultra-low volume aerial application of an azadirachtin-based insecticide for control of the pine false webworm, Acantholyda erythrocephala (L.) (Hymenoptera: Pamphiliidae), in Ontario, Canada

The efficacy of an aerial application at ultra-low volume of a 3% azadirachtin-based insecticide (Fortune AZA 3%) at a nominal application rate of 50 g azadirachtin ha−1 was evaluated for control of pine false webworm, Acantholyda erythrocephala (L.). Applications were made to three separate blocks in red pine plantations in south-central Ontario. Population indices of pine false webworm were compared between the treated blocks and three untreated blocks. Spray application was timed to coincide with the preponderance of egg hatch. Numbers of insects declined in all blocks between the adult emergence period and the subsequent larval generation, but decline in treated blocks was significantly greater. Reductions of arboreal stages (70-90% vs 5-50 %), frass drop estimates (0.10-0.13 vs 1.16-2.65 g/m2 d−1) and defoliation (10.5-15.5% vs 35-92.9%) all indicated significant differences in pine false webworm populations in treated as compared to untreated blocks. Mean deposits of azadirachtin A ranging from 0.44 to 1.47 wg g−1 in the canopy were well in excess of the 0.29 wg g−1 levels producing 91% mortality in laboratory bioassays. Azadirachtin-based insecticides provided good control of pine false webworm larvae in semi-mature and mature red pine plantations and would be suitable for use in an integrated control program for this insect.

An Overview of the BIOLOGY of the Wharf Borer Beetle ( Nacerdes melanura L., Oedemeridae) a Pest of Wood in Marine Structures

The UK distribution of N. melanura is reported, based on records from museum collections, government laboratories and a field survey of wooden marine structures and driftwood along the English and Welsh coastlines. The global distribution is also reported, based on a questionnaire survey. The life cycle of the wharf borer under different environmental conditions is described and the environmental conditions over the adult emergence period presented. The cellulase complex, xylanase and a range of dissacharases were present in the larval digestive tract when tunnelling archaeological oak.

Some Characteristics of Long-Term Dynamics of Adult Emergence Periods of Ermine Moth Parasitoids in Different Ecosystems

During the 25-year-long period of investigations carried out in ecosystems including bird cherry, spindle tree, apple tree, and hawthorn in Lithuania the emergence season of adult parasitoids of various ermine moths was recorded in the time span from the second five-day period of June till the second five-day period of August. The obtained curve shapes of adult parasitoid emergence demonstrated the nature of asymmetry in a great number of occurrences and the nature of symmetry in individual cases. Shorter emergence periods of adult parasitoids proved to be more frequent. The mean value of long-term dynamics of the adult emergence period duration of individual parasitoid species in different ecosystems varied from 7.5 ± 2.5 to 22.2 ± 1.4 days. Duration of emergence cycles was different and varied from three to eight years. An extension of various parasitoid species manifestation and phenological picture dispersion in different ecosystems were registered.

Variability in Quality of Trichogramma brassicae (Hymenoptera: Trichogrammatidae) from Commercial Suppliers in Germany

The quality of Trichogramma brassicae Bezd. (= T. maidis n. sp.) (Hymenoptera: Trichogrammatidae) produced in 1998 and 1999 by four companies (AMW Nuetzlinge GmbH, Biocare GmbH, BASF, and Landi) to control the European corn borer Ostrinia nubilalis Hübner (Lepidoptera: Pyralidae) was measured. Standard methods developed by the International Organization for Biological Control (IOBC) were used to assess sex ratio, number of females released per hectare, longevity, fecundity, and capacity to parasitze the natural host. The percentage of females was between 50.7 ± 1.5 and 68.3% ± 1.9%, always higher than the 50% standard agreed upon by the IOBC. The number of parasitized eggs released per hectare was, with one exception, considerably higher than the standard of 100,000 given by the companies. In five cases, it was over 150,000 parasitized host eggs per hectare. The emergence rate varied from 72.3 ± 1.3 to 90.6 ± 0.9%. Therefore, the number of females released per hectare varied between 38,532 and 86,966. The survival rate (to day 7) fluctuated between 16.7 and 66.7% and was much lower than the optimistic IOBC standard of 80%. The fecundity on the mass rearing host Sitotroga cerealella (Olivier) and on the target host O. nubilalis was also often lower than the IOBC standards, and this especially in the first release, which could partly be due to longer storage. The releasing units contained parasitoids in different development stages to prolong the period of adult emergence and thereby extend the duration of treatment. Parasitoid emergence for the two treatments together continued for about 4 weeks (June 30 to July 27, 1998, and June 23 to July 21, 1999). In both test years, the two parasitoid releases produced strongly overlapping periods of adult emergence that coincided with the egg-laying peak of the pest in the field.