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1.
The painted apple moth (PAM), Teia anartoides (Walker) (Lepidoptera: Lymantriidae) made a recent incursion into New Zealand. A nucleopolyhedrovirus (NPV), Orgyia anartoides NPV (OranNPV), originally isolated from PAM in Australia, was tested for its pathogenicity to PAM and a range of non‐target insect species found in New Zealand, to evaluate its suitability as a microbial control for this insect invader. Dosage‐mortality tests showed that OranNPV was highly pathogenic to PAM larvae; mean LT50 values for third instars ranged from 17.9 to 8.1 days for doses from 102 to 105 polyhedral inclusion bodies/larva, respectively. The cause of death in infected insects was confirmed as OranNPV. Molecular analysis established that OranNPV can be identified by PCR and restriction digestion, and this process complemented microscopic examination of infected larvae. No lymantriid species occur in New Zealand; however, the virus had no significant effects on species from five other lepidopteran families (Noctuidae, Tortricidae, Geometridae, Nymphalidae and Plutellidae) or on adult honeybees. Thus, all indications from this initial investigation are that OranNPV would be an important tool in the control of PAM in a future incursion of this species into New Zealand.  相似文献   
2.
Although selective pesticides are recommended to use in integrated pest management (IPM) programmes, they could adversely affect biological agents. So, the aim of the current study was to investigate the LC30 of pirimicarb and thiamethoxam on Hippodamia variegata. Two pesticides, pirimicarb and thiamethoxam, when applied at concentrations of 1522.8 and 251.3?mg (ai)/L, respectively, on the third instar larvae of the insect, produced 30% mortality. Also, results showed that neither pirimicarb nor thiamethoxam affect stage age distribution (cx), fecundity (eggs/female) and adult development time. These two pesticides extended preadult duration significantly (p?<?0.0001, F?=?31.22, df?=?122). Also, survival rate (lx) and age-specific reproductive value (vx) decreased and some changes in age-specific life expectancy (ex) happened. Generally, more adverse effects were found in the population treated by thiamethoxam. The results showed that pirimicarb and thiamethoxam have potential to harm the predatory ladybird in IPM programme, though in sublethal doses.  相似文献   
3.
A hallmark of anoxia tolerance in western painted turtles is relative constancy of tissue adenylate concentrations during periods of oxygen limitation. During anoxia heart and brain intracellular compartments become more acidic and cellular energy demands are met by anaerobic glycolysis. Because changes in adenylates and pH during anoxic stress could represent important signals triggering metabolic and ion channel down-regulation we measured PCr, ATP and intracellular pH in turtle brain sheets throughout a 3-h anoxic-re-oxygenation transition with 31P NMR. Within 30 min of anoxia, PCr levels decrease 40% and remain at this level during anoxia. A different profile is observed for ATP, with a statistically significant decrease of 23% occurring gradually during 110 min of anoxic perfusion. Intracellular pH decreases significantly with the onset of anoxia, from 7.2 to 6.6 within 50 min. Upon re-oxygenation PCr, ATP and intracellular pH recover to pre-anoxic levels within 60 min. This is the first demonstration of a sustained reversible decrease in ATP levels with anoxia in turtle brain. The observed changes in pH and adenylates, and a probable concomitant increase in adenosine, may represent important metabolic signals during anoxia.  相似文献   
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Native to Asia, Harmonia axyridis (Pallas) (Coleoptera: Coccinellidae) is considered an invasive alien ladybird in Europe and North America, where it was widely introduced as a biological control agent of aphids and coccids. In Europe, H. axyridis was sold by various biological control companies from 1995 in France, Belgium and the Netherlands, and was also intentionally released in at least nine other countries. It has spread very rapidly, particularly since 2002, and is now regarded as established in thirteen European countries. The established range extends from Denmark in the north to southern France in the south, and from Czech Republic in the east to Great Britain in the west. In this paper we map the spread and distribution of H. axyridis in Europe, and examine the situation on a country-by-country basis. We report first records of the species in five countries; Spain, Sweden, Denmark, Czech Republic and Italy; and first evidence of H. axyridis establishment in the latter three countries. Despite releases of H. axyridis in Portugal, Spain and Greece, there is little evidence of establishment in southern Europe. It is predicted that the spread and increase within Europe will continue and that H. axyridis will become one of the most widely distributed coccinellids in the continent.  相似文献   
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Dissemination of microbial biocontrol agents via predators may have advantages for safe spore dispersal to targeted pests with the added benefit of predation. A laboratory study was conducted to test the target-oriented dissemination of conidia of Beauveria bassiana using larvae of both the multicoloured Asian lady beetle (Harmonia axyridis) and common green lacewing (Chrysoperla carnea) for control of aphids. Maximum dry conidial attachment occurred within approximately 7 min after exposure. After release of the treated predators on leaves of Chinese cabbage, within 12 hours lacewing larvae dispersed 89% of the attached conidia while Asian lady beetles dispersed 93%. Both predators dispersed conidia up to 2.4 m from the release site. Leaf disk bioassays were conducted to compare two application methods; the dissemination of conidia of B. bassiana by predators and the direct application of conidial suspensions. Mortality in sprayed aphids was 91±2.1% compared to 88±2.1 and 84±4.2%, respectively, when conidia were disseminated by lacewings and lady beetles. Predation was not affected in treated lacewing larvae whereas there was a 20% reduction in predation by lady beetle larvae. It appears that B. bassiana can be effectively delivered using certain insect predators.  相似文献   
8.
Coccinella septempunctata and Propylea quatuordecimpunctata in North America have documented invasive capacity. Studies are needed to identify relevant life-history parameters responsible for their successful spatial spread. This study is a detailed analysis of phenotypic variation in reproductive traits of several Nearctic and Palearctic populations of these two coccinellid species. From 47 to 61% of C. septempunctata females laid their first batch of eggs within the first two weeks of their adult life. Within P. quatuordecimpunctatapopulations, 56 to 83% of females initiated oviposition within 2 weeks. The remaining females either had preoviposition periods > 2 weeks or never laid eggs during a 60-day observation period. Analysis of daily fecundity revealed differences in oviposition strategies among females within each population. Repeatability estimates of daily parity for C. septempunctata populations were 0.32 for Iowa (USA), 0.35 for Delaware (USA), 0.28 for France, and 0.33 for Ukraine. Repeatability estimates for P. quatuordecimpunctata populations were 0.35 for Canada, 0.25 for France, and 0.33 for Turkey. The within-female component accounted for most of the variation in daily parity; this was due to female variability in their daily oviposition rates. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   
9.
Anthropogenic sound is increasingly considered a major environmental issue, but its effects are relatively unstudied. Organisms may be directly affected by anthropogenic sound in many ways, including interference with their ability to detect mates, predators, or food, and disturbances that directly affect one organism may in turn have indirect effects on others. Thus, to fully appreciate the net effect of anthropogenic sound, it may be important to consider both direct and indirect effects. We report here on a series of experiments to test the hypothesis that anthropogenic sound can generate cascading indirect effects within a community. We used a study system of lady beetles, soybean aphids, and soybean plants, which are a useful model for studying the direct and indirect effects of global change on food webs. For sound treatments, we used several types of music, as well as a mix of urban sounds (e.g., sirens, vehicles, and construction equipment), each at volumes comparable to a busy city street or farm tractor. In 18‐hr feeding trials, rock music and urban sounds caused lady beetles to consume fewer aphids, but other types of music had no effect even at the same volume. We then tested the effect of rock music on the strength of trophic cascades in a 2‐week experiment in plant growth chambers. When exposed to music by AC/DC, who articulated the null hypothesis that “rock and roll ain't noise pollution” in a song of the same name, lady beetles were less effective predators, resulting in higher aphid density and reduced final plant biomass relative to control (no music) treatments. While it is unclear what characteristics of sound generate these effects, our results reject the AC/DC hypothesis and demonstrate that altered interspecific interactions can transmit the indirect effects of anthropogenic noise through a community.  相似文献   
10.
Adults of the lady beetle Hippodamia convergens Guérin-Méneville requiring aphids for egg production, were fed suboptimal amounts of apteriform virginoparous larvae or alatiform gynoparous larvae of the green peach aphid, Myzus persicae (Sulz.), and artificial diet ad lib. The beetles initiated oviposition sooner and deposited significantly more eggs when supplied with the same weight of apterous virginoparous morph. The possible nutritional, hormonal, and ecological implications of the findings are discussed.
Zusammenfassung Die Eiproduktion des Marienkäfers Hippodamia convergens, welcher hierzu Blattläuse als Nahrung benötigt, wurde bei Fütterung mit zwei verschiedenen Morphen der Blattlaus Myzus persicae untersucht. Der Verzehr derselben Menge flügelloser Virginoparen führte im Vergleich zu geflügelten Gynoparen zu früherer und signifikant erhöhter Eiabgabe. Der hormonale und ernährungsphysiologische Hintergrund und die ökologische Bedeutung dieser Ergebnisse werden diskutiert.
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