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Sunn Pest (Hemiptera: Scutelleridae) Oviposition and Egg Parasitism in Syria  [PDF]
M. El Bouhssini,M. Abdulhai,A. Babi
Pakistan Journal of Biological Sciences , 2004,
Abstract: Sunn Pest (Eurygaster integriceps Puton.) is the most important insect pest of wheat in Syria. Hymenopteran egg parasitoids are among the natural enemies that contribute to the reduction of Sunn Pest populations. Our surveys from 1997-1999 revealed six egg parasitoid species: Scelionidae; Trissolcus grandis (Thomson), T. simoni (Mayr), T. vassilievi (Mayr) and Gryon fasciatus (Priener) and Encyrtidae: Ooencyrtus fecundus (Ferrière and Voegelé) and O. telenomicida (Vassiliev). They were active in the spring, about 2 weeks after Sunn Pest migrated to cereal fields from its overwintering sites. The level of parasitism varied from year to year, in 1998-1999 and 1999-2000 seasons it reached 100% at Azaz, Syria at the end of the seasons. These natural enemies seem to be playing an important role in regulating Sunn pest population and thus should be conserved.
Integrated pest management: theoretical insights from a threshold policy
Costa, Michel I da Silveira;Faria, lucas Del B;
Neotropical Entomology , 2010, DOI: 10.1590/S1519-566X2010000100001
Abstract: an integrated pest management is formulated as a threshold policy. it is shown that when this strategy is applied to a food web consisting of generalist, specialist predators and endemic and pest prey, the dynamics can be stable and useful from the pest control point of view, despite the dynamical complexities inherent to the application of biocontrol only. in addition, pesticide toxicity depends rather on the species intrinsic parameters than on the chemical agent concentration.
Studies on Effects of Artificial Diets on Pre-oviposition, Oviposition Period, Fecundity and Longevity of Atherigona orientalis (Schiner) (Diptera, Muscidae)  [PDF]
O.K. Ogbalu,J.J. Emelike,C.C. Obunwo
Journal of Applied Sciences , 2005,
Abstract: The study on the effects of artificial diets on some aspects of the biology of Atherigona orientalis was undertaken in order to establish a rearing diet for the dipterous pest of peppers and tomatoes in Nigeria. Establishing a rearing diet for the pest will lead to having a detailed study of other aspects of the biology of the pest. Two artificial diets (3% honey solution and a diet mixture of dry baker`s yeast, sugar and water) were used to assess their effects on pre-oviposition, oviposition periods, fecundity and longevity of Atherigona orientalis. Mean pre-oviposition period was shortest for flies fed on the diet mixture with an average of 1.77 ± 0.2 days (range: 1-3 days), whereas mean pre-oviposition periods for adults fed on 3% honey solution was longer (2.8 ± 0.2; range: 2-5 days). A total of 2465 eggs were recorded for 21 mated females fed on the diet mixture as against 1204 from 21 mated females fed on 3% honey solution. A very loose relationship ( = 9.43 + 0.04 x; r = 0.35) was observed between longevity and fecundity of females of A. orientalis.
Oviposition behavior of Grapholita molesta Busck (Lepidoptera: Tortricidae) at different temperatures
Silva, EDB da;Kuhn, TMA;Monteiro, LB;
Neotropical Entomology , 2011, DOI: 10.1590/S1519-566X2011000400001
Abstract: cultivation of temperate-climate fruits is economically important for brazil. grapholita molesta busck is a pest that causes damage to apples, peaches, plums, and pears growing in different micro-regions of southern brazil, and understanding its reproductive behavior is essential to develop control strategies. the objective of this study was to ascertain the influence of different temperatures (13, 16, 19, 22, and 25oc) on the oviposition behavior of g. molesta. females of g. molesta were placed in individual plastic containers, and the pre-oviposition period and the number of eggs laid were assessed until adult death. temperature influenced the pre-oviposition period, and females kept at 22o were the first to lay their eggs. oviposition occurred over a longer period of time at 13oc than at the higher temperatures. the highest total number of eggs was obtained at 19oc, with the mean daily oviposition being directly proportional to the temperature. there was a negative interaction between the pre-oviposition period and the total number of eggs laid by females. the most suitable temperature for oviposition of g. molesta was 19oc.
CHIRONOMID COMMUNITIES IN THE LITTORAL ZONE ON THE WESTERN COAST OF THE  [cached]
Lyubov Kravtsova
Chironomus Newsletter on Chironomidae Research , 2009,
Abstract: The spatial distribution of chironomid communities in the littoral zone (0-20 m) of the western coast of the southern Baikal basin is investigated. The fauna is composed of 16 species and forms of chironomid larvae, comprising 10 communities. It has been found that the communities are characterized by rather poor species diversity; Shannon’s index varies from 0.7 to 2.1 bit. Their distribution is affected by hydro-lithodynamic conditions, type of bottom sediments and macrophyte development. The peak of maximal biomass of chironomid larvae on the facies of non-rounded rock debris near Berezovy Cape is recorded in spring.
Nutrient conditions and chironomid productivity in Kolkata, India: assessment for biomonitoring and ecological management  [cached]
Soumi Nandi,Gautam Aditya,Goutam K. Saha
Journal of Limnology , 2012, DOI: 10.4081/jlimnol.2012.e34
Abstract: The chironomid diversity in the water bodies are useful indicators of the nutrient and environmental states. A spatial scale analysis on the relative abundance of the chironomid species in the context of selected nutrient indicators like organic carbon (C), potassium ions (K+), nitrate (NO3ˉ), and phosphate (PO42ˉ) of the water bodies was assessed to justify the use of chironomids in environmental biomonitoring. Analysis of a sample of 90 data from eight different ponds of Kolkata, India, revealed the presence of 11 chironomid species in different relative densities. The chironomid immature productivity was found to be positively correlated with C and PO42ˉ of the water bodies, while no definite significant correlation was observed for K+, NO3ˉ. Based on these nutrients and the productivity of chironomids the ponds could be distinguished from one another. The abundance of three species of chironomid midges, Chironomus striatipennis, Chironomus circumdatus and Kiefferulus calligaster were prominent in all the water bodies. Cluster analysis showed that these species were highly correlated in their abundance contrast to others. The correspondence analysis showed distribution of the chironomid species to differ against the variance of nutrients. The results are supportive of the use of chironomid larvae in biomonitoring and ecological restoration of urban water bodies, through monitoring the nutrient status and the chironomid species assemblage. In this instance the chironomid species C. striatipennis, C. circumdatus and K. calligaster can specifically act as indicator of the nutrient state of the ponds.
Oviposition Site-Selection by Bactrocera dorsalis Is Mediated through an Innate Recognition Template Tuned to γ-Octalactone  [PDF]
Kamala Jayanthi Pagadala Damodaram, Vivek Kempraj, Ravindra Mahadappa Aurade, Ravindra Kothapalli Venkataramanappa, Bakthavatsalam Nandagopal, Abraham Verghese, Toby Bruce
PLOS ONE , 2014, DOI: 10.1371/journal.pone.0085764
Abstract: Innate recognition templates (IRTs) in insects are developed through many years of evolution. Here we investigated olfactory cues mediating oviposition behavior in the oriental fruit fly, Bactrocera dorsalis, and their role in triggering an IRT for oviposition site recognition. Behavioral assays with electrophysiologically active compounds from a preferred host, mango, revealed that one of the volatiles tested, γ-octalactone, had a powerful effect in eliciting oviposition by gravid B. dorsalis females. Electrophysiological responses were obtained and flies clearly differentiated between treated and untreated substrates over a wide range of concentrations of γ-octalactone. It triggered an innate response in flies, overriding inputs from other modalities required for oviposition site evaluation. A complex blend of mango volatiles not containing γ-octalactone elicited low levels of oviposition, whereas γ-octalactone alone elicited more oviposition response. Na?ve flies with different rearing histories showed similar responses to γ-octalactone. Taken together, these results indicate that oviposition site selection in B. dorsalis is mediated through an IRT tuned to γ-octalactone. Our study provides empirical data on a cue underpinning innate behavior and may also find use in control operations against this invasive horticultural pest.
Quasi-Double-Blind Screening of Semiochemicals for Reducing Navel Orangeworm Oviposition on Almonds  [PDF]
Kevin Cloonan, Robert H. Bedoukian, Walter Leal
PLOS ONE , 2013, DOI: 10.1371/journal.pone.0080182
Abstract: A three-step, quasi-double-bind approach was used as a proof-of-concept study to screen twenty compounds for their ability to reduce oviposition of gravid female navel orangeworm(NOW), Ameylois transitella (Lepidoptera: Pyralidae). First, the panel of compounds, whose identity was unknown to the experimenters, was tested by electroantennogram (EAG) using antennae of two-day old gravid females as the sensing element. Of the twenty compounds tested three showed significant EAG responses. These three EAG-active compounds and a negative control were then analyzed for their ability to reduce oviposition via small-cage, two-choice laboratory assays. Two of the three compounds significantly reduced oviposition under laboratory conditions. Lastly, these two compounds were deployed in a field setting in an organic almond orchard in Arbuckle, CA using black egg traps to monitor NOW oviposition. One of these two compounds significantly reduced oviposition on black egg traps under these field conditions. Compound 9 (later identified as isophorone) showed a significant reduction in oviposition in field assays and thus has a potential as a tool to control the navel orangeworm as a pest of almonds.
Phenology of some chironomid species (Diptera, Chironomidae) of the Middle Urals  [cached]
Andrey B Krasheninnikov
Fauna Norvegica , 2012, DOI: 10.5324/fn.v31i0.1371
Abstract: Flight period results of chironomid species from the Middle Urals are grouped into eight categories. Six different peaks of chironomid flight activity during the year are established, namely: early-spring, late-spring, July, late-summer, early-autumn and winter. The flight periods of chironomids from the Middle Urals and southern Swedish lakes are compared. doi: 10.5324/fn.v31i0.1371. Published online: 17 October 2012.
Pilot-scale study of removal effect on Chironomid larvae with chlorine dioxide
SUN Xing-bin,CUI Fu-yi,ZHANG Jin-song,GUO Zhao-hai,ZHAO Kai,LIU Li-jun,LV Wei-min,
SUN Xing-bin
,CUI Fu-yi,ZHANG Jin-song,GUO Zhao-hai,ZHAO Kai,LIU Li-jun,LV Wei-min

环境科学学报(英文版) , 2006,
Abstract: Chironomid larvae propagated excessively in eutrophic water body and could not be effectively inactivated by the conventional disinfection process like chlorination due to its stronger resistance to oxidation. In this paper, a pilot-scale study of chlorine dioxide preoxidation cooperating with routine clarification process for Chironomid larvae removal was conducted in Shenzhen Waterworks in Guangdong Province, China. The experimental results were compared with that of the existing prechlorination process in several aspects, including the Chironomid larvae removal efficiencies of water samples taken from the outlets of sedimentation tank, sand filter, the security of drinking water and so on. The results showed that chlorine dioxide might be more effective to inactivate Chironomid larvae than chlorine and Chironomid larvae could be thoroughly removed from water by pre-dosing chlorine dioxide process. The GC-MS examination and Ames test further showed that the sort and amount of organic substance in the treated water by chlorine dioxide preoxidation were evidently less than that ofprechlorination and the mutagenicity of drinking water treated by pre-dosing chlorine dioxide was substantially reduced compared with prechlorination.
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