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Showing 1 to 20 of 73 for “"instars"”.
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Morphology and taxonomy of the first instars of the genus <i>Cerococcus</i> Comstock (Homoptera:Coccoidea:Cerococcidae)
… identification. This detailed study of the first instars is one step in the revision of the genus and reevaluation of the taxa which have been referred to the genus. The first instars of 31 species of <i>Cerococcus</i> are included in this study. Each species studied is fully described, including …
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Chemoreception of sugars and amino acids in female fourth and sixth instars of the spruce budworm, Choristoneura fumiferana (Clem.)
… sugars tested on the lateral sensillum, fourth instars responded to melibiose, sucrose and raffinose. Sixth instars exhibited an order of sensitivity that was in accordance with earlier behavioural work on feeding responses; sucrose $>$ fructose $>$ m-inositol. A neuron in the lateral stylconic …
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A morphological and systematic study of the first and second instars of the Kermesidae in the Nearctic region (Homoptera: Coccoidea)
The Cocco idea or scale insects are among the most important pests of sylvicultural, ornamental, agricultural and greenhouse plantings throughout the world. There are 21 families comprising 6,000 species. Direct injury occurs from the withdrawal of sap while feeding and from the production of …
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Developmental and reproductive ecology of Melanoplus femurrubrum (De Geer) and some other melanopline grasshoppers (Orthoptera, Acrididae)
… in Virginia had five, six, seven, and eight instars, determined by antennal segment counts. Adults with five instars were uncommon, and six and seven-instar adults were the most abundant morphs. Laboratory studies showed that decreasing temperature decreased both the number of instars, and …
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Life History and Case Building Behaviors of Phylloicus ornatus (Banks) (Trichoptera: Calamoceratidae) In Two Spring Fed Tributaries in the Central Edwards Plateau Bioregion of Texas
… rearings indicated a multivoltine cycle. First instars differ from late instars in number of labral setae and in having a unique spur-like claw on each lateral hump. Larval development was asynchronous with second through fifth instars and pupae present most months. First instars were present …
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Ecology, behavior, impact, and an integrated pest management strategy for the orangestriped oakworm, Anisota Senatoria (J. E. Smith), in the urban landscape
… law showed aggregation was greatest among early instars, followed by third instars and late instars. A fixed level precision sampling plan was developed based on the number of eggs and early instars present in low strata. The tree growth regulator paclobutrazol significantly reduced Q. Phellos …
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Group formation and dispersal in the German cockroach, Blattella germanica (L.) (Dictyoptera: Blattellidae)
… caused increased dispersal of females and mid-instars. The mid-instars were the primary dispersers in each experiment. Early instars, excluding escapees, dispersed least. The results of these studies indicate the females of a population can mediate the behavior of that population and its …
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Impact of the microbial pesticide Bacillus thruingiensis Berliner subsp. kurstaki on Hymenopterous parasites of the imported cabbageworm, Pieris rapae (L.) (Lepidoptera: Pieridae)
… and successful pupation of P rapae fourth instars parasitized by C. rubecula to B. thuringiensis endotoxin at dosages of 850, 85, and 8.5 I.U./ml was examined. After day two, the LC<sub>50</sub>'s of parasitized fourth instars were approximately thirty times higher than that of …
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Components of seasonal soybean infestation by Heliothis zea in eastern Virginia, with emphasis on multivariate analysis of field susceptibility
… host crops were studied in eastern Virginia. Six instars occur. The larval population in corn is the reservoir for the generation in soybeans. An estimator, based on the reservoir population, permitted calculation of the larval density in soybeans. An index, based on blacklight trap and emergence …
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Life history, survival, growth, and production of hydropsyche slossonae in Mill Creek, Virginia
… and June which hatched in 13 days. Five larval instars were recorded with most individuals overwintering in III and IV instars. Pupation and emergence occurred primarily over a six week period in May and June. No mortality in the egg stage (0%) was detected, while high mortality in I instar …
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Ecology of the stalk borer Papaipema nebris (Guenee), (Lepidoptera:noctuidae), in the southwestern Virginia no-till corn agroecosystem
… (SB), Papaipema nebris Gn. exhibited from 7 to 9 instars when reared on a meridic diet in a control-led environment. Both sexes went through variable numbers of instars before pupation. Head capsule width measurements did not form discrete sets, and overlap occurred between adjacent instars. In …
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Species composition and larval instar population structure of Scarabaeids in forestry in the Natal Midlands
… width pattern was used to determine the larval instars responsible for the damage. High incidences of seedling damage was recorded from December to April. Several morphospecies were found I damaging seedlings simultaneously. Morphospecies 1, 2, 3, 4, 5 and 6 were responsible for the damage but …
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Caracterização e distribuição de Elmidae (Insecta, Coleoptera) no Rio da Fazenda, Floresta da Tijuca, Rio de Janeiro, RJ
… smaller larvae predominating in summer and later instars appearing in winter. On the other hand, Phanocerus clavicornis presented the later instars appearing in summer and smaller larvae in winter. Apparently the main environmental variables affecting Elmidae spatial and temporal distribution were …
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Effects of Dietary Lutein on the Parsnip Webworm, Depressaria Pastinacella (Lepidoptera: Elachistidae)
I examined lutein sequestration by sixth instars from populations in western North America that experience different UV intensities, as well as host plant furanocoumarins. Total furanocoumarins and total linear furanocoumarins were negatively correlated with UV irradiance (UVI), whereas total …
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Effects of an insecticide on German cockroach behavior
… behavior. Adult males, adult females, and middle instars were repelled from aquaria containing the insecticide vapors. Early instars sought shelter in the pores of water sponges. No differences in behavior due to reproductive state were observed as females with oothecae and females without …
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Biology and ecology of Frumenta nundinella (Zeller) (Lepidoptera: Gelechiidae) and its impact on horsenettle (Solanum carolinense L.)
… The larvae attack the plant in two ways: first instars web the terminal leaves together and form a round hollow chamber within which they feed on the growth tip of the plant, or they enter berries and consume all of the seeds. There are two generations per year, each being about 50 days. The …
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Effect of Intercropping and Trap Cropping on the Diamondback Moth, Plutella Xylostella L., Its Natural Enemies and Other Brassicaceous Pests, And, Studies on Diadegma Insulare (Cresson), the Major Diamondback Moth Parasitoid
… with its host when it developed in second instars, where survival to cocoon formation and adult emergence was also significantly higher than in third- or fourth-instar hosts. A greenhouse study at varying parasitoid and host densities indicated that DBM larvae dispersed from host plants …
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Oidaematophorus monodactylus (L.) and Bedellia somnulentella (Zeller): two potential biological control agents of hedge bindweed in southwestern Virginia
… This indicated that inundative releases of late instars in early June could reduce the growth rate and seed production of hedge bindweed plants. An estimate of the initial direct cost of rearing 10,000 third instars for a June release totaled a little less than $8,000; of which 30% are …
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Phenology, impact, and rearing of Lycorma delicatula (White) (Spotted Lanternfly) in Virginia
… however a greater proportion of third instars developed into fourth instars in the apical meristem treatment. I suggest future L. delicatula rearing research include the use of potted plants and/or multiple species. Though I had low success in rearing adult L. delicatula to produce egg …
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Environmental controls in the seasonal succession and synchronization of development in some pond species of damselflies (Odonata: Zygoptera)
… influenced diapause in the penultimate and final instars, by differences in thermal growth coefficients in different instars during spring development, and by a threshold temperature for emergence higher than that for nymphal development. Members of the second group overwinter as eggs in late …
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