1,762 research outputs found
New Host Records and Developmental Notes on the Pear Slug \u3ci\u3eCaliroa Cerasi\u3c/i\u3e (Hymenoptera: Tenthredinidae), Feeding on \u3ci\u3eCotoneaster\u3c/i\u3e and \u3ci\u3eChaenomeles\u3c/i\u3e Species.
The pear slug. Caliroa cerasi was collected and reared to adulthood on flowering quince and three species of Cotoneaster. This is the first record of C. cerasi attacking any member of the genus Chaenomeles and the first confirmation of feeding on Cotoneaster in North America. Adult emergence, oviposition, and larval development were evaluated under both laboratory and field conditions. Females lay an average of 48 eggs, with about two-thirds of the oviposition occurring during their first 24 hours. A method for monitoring adult emergence in the field was developed
Field applications of entomopathogenic fungi against Rhagoletis cerasi
Two myco-insecticides, Naturalis-L (Beauveria bassiana) and PreFeRal®WG
(Paecilomyces fumosoroseus), were applied against adult R. cerasi (Diptera: Tephritidae)
in two orchards in north-western Switzerland in summer 2006. Both products were applied
at a concentration of 5.75x104 CFU / ml. With four applications at seven day intervals the
whole flight period of R. cerasi was fully covered. During this period (5th June – 6th July)
the temperature averaged 19.2°C, total precipitation was 60 mm. Under these conditions
Naturalis-L significantly reduced the number of damaged fruit (efficacy: 69-74%), whereas
damage was not significantly reduced with PreFeRal®WG (efficacy: 27%). Fungus
infested flies were found on the yellow sticky traps proving that the myco-insecticides
worked as predicted.
Climatic conditions were different in 2007: temperature averaged 15.9°C (16th May – 4th
July), total precipitation was 281 mm. In 2007 only Naturalis-L was tested: with five
applications an efficacy of 73% and 78% was obtained on the cherry varieties Langstieler
and Dolleseppler, respectively. However, for the latest ripening and most infested variety
Schauenburger only an efficacy of 18% was observed. In these cherries a high number of
young larvae were found indicating that the efficacy was low at the end of the treatment
period. In conclusion a control of R. cerasi with myco-insecticides seems possible.
However, application regime still has to be improved and should not only be adapted to the
flight period of R. cerasi, but also to the cherry varieties
Migration und Ausbreitung der Kirschfruchtfliege innerhalb von Obstanlagen – Möglichkeit der biologischen Bodenbehandlung
The European cherry fruit fly (Rhagoletis cerasi) is the only pest insect which makes a
insecticide treatment of cherry fruit necessary. With regard of residue free cherries a
biocontrol method for R. cerasi by soil applications seems attractive. However, soil
treatments can only be effective if the migration of flies is low. In order to examine the
potential of soil treatments and to understand the dispersal behaviour of R. cerasi in
orchards, experiments using nettings to cover the soil were conducted. The
experiments were arranged in commercial, organically managed orchards. The
nettings reduced fruit infestation by 90%. In addition, it was shown that the flies move
only very short distances (less than 5 m) within orchards. Thus, soil treatments are an
interesting strategy to control R. cerasi in extensively managed orchards
Field evaluation of entomopathogenic nematodes against orchard pests
Survival of pest in micro-plot trials (container studies) or field plot trials was monitored after exposure to commercially used EPN strains. Experimental plots were artificially infested with pest larvae that naturally burrowed into the soil for diapause. Either larval mortality or adult emergence, was assessed to estimate the control effect of the EPN treatment. Here we present preliminary results from three ongoing projects
Tree-squares in Anatolia : what does an emergent public space mean?
Urban places, besides their physical characteristics, are regarded as grounds where personal or
collective meanings are created and accumulated. An individual can capture the meaning of a place, or create new meanings by relying on his/her own feelings and experiences. This research, by discussing the idea of togetherness of meaning and design in urban spaces, presents trees both as place making and meaning generating features, which honors the local identity of a site. Tree-squares are, therefore, the unique urban public places where this relationship is observed clearly. The researcher’s encounter with a Çınaraltı Square - a Turkish term used to define public places under massive and historical plane trees and will be referred as Tree-Square within the scope of this paper - which is marked by a plane tree that is called Musa (Moses) Plane in Antakya/Turkey has triggered an idea of questioning the urban planning and design approaches beyond the broadly accepted role of trees as natural and aesthetic beings in cities. Later on, Yalvaç Plane in Yalvaç/Isparta site, and the outstanding public place under its tremendous branches carried this wonder one step further, since this Tree-Square was not only an attractive place with a magnificent plane tree, but also the heart of the city. It was unplanned and un-envisioned by any kind of legal planning or design authority; instead, it was emerged and developed out of the cultural beliefs and traditions. This emergent public space is a product of a long term social and historical interaction process that created the main public place of a medium-sized Turkish city, as in many Anatolian cities. It carries significant urban qualities, such as forming the heart of cities and having a visible impact on the urban macroform. Therefore, a case study research has been conducted in Yalvaç Tree-Square to gain a comprehensive grasp of the social and spatial organization of an urban place that is dominated by a historical plane tree. In this sense, the role of Yalvaç Plane in the historical and spatial development of an urban space will be evaluated by relying on socially produced meaning in the built environment
Wirkung verschiedener Insektizide und Larven des 2-Punkt-Marienkäfers Adalia bipunctata als Vorblütenbehandlungen gegen die Kirschenblattlaus Myzus cerasi in biologischen Kirschenanlagen
Fragestellung:
Prüfung verschiedener biologischer Insektizide und Larven des 2-Punkt-Marienkäfers Adalia bipunctata als Vorblütenbehandlung gegen die Kirschenblattlaus Myzus cerasi in biologischen Kirschenanlage
Drosophila suzukii control using Kaolin, lime and rock dusts.
The Spotted wing drosophila, Drosophila suzukii, is an invasive pest in Europe and North America, infesting various soft-skinned fruits. Because D. suzukii attacks ripening fruits shortly before harvest, only insecticides with short pre-harvest intervals can be applied. Alternatively, kaolin, lime and rock dusts are non-toxic to non-target organisms, but the whitish coating on fruits potentially deters oviposition of D. suzukii. Therefore, we tested oviposition deterrence and insecticidal effects of such substances. Female D.suzukii flies were exposed to treated blueberries under laboratory conditions for 24 hours. Kaolin, clinoptilolite, clinoptilolite + Heliosol (pine-oil based wetting agent) and calcium carbonate significantly reduced oviposition, whereas calcium hydroxide only had a marginal effect and diatomaceous earth had no significant effect. None of the tested products had an insecticidal effect. Kaolin, lime and rock dusts are therefore a promising tool to reduce damage of D. suzukii in soft-skinned fruits
Kann der Einsatz entomopathogener Nematoden zur nachhaltigen Bekämpfung der Kirschfruchtfliege beitragen?
The cherry fruit fly, Rhagoletis cerasi L., is the major pest of sweet cherries in Europe. Currently, no efficient control method is available and there is the risk of increasing population densities of this pest. Entomopathogenic nematodes caused high mortality of last instar maggots, when entering the soil for pupation, under laboratory and field conditions. First field applications of these biocontrol agents against pupating larvae in 2005 should test their efficacy to reduce pest densities. Accompanying field observa-tions were made to evaluate the degree of natural mortality of the cherry fruit fly during the pupation phase in order to decide if the application of nematodes could substan-tially contribute to control this pest. According to the results in this year, natural mortal-ity factors reduced the cherry fruit fly population from the period between larvae leav-ing the fruit until hatching of adults in the following year by 95%. The emergence rate of adult flies in spring 2006 was low (10 flies/qm) and no significant differences in the densities of emerging flies in untreated and treated areas were detected. Thus, the effect of applying nematodes remained unclear and additional methods are needed to define their impact separately from natural mortality
Addendum to Barringer (2018): First record of the European cherry fruit fly, \u3ci\u3eRhagoletis cerasi\u3c/i\u3e (Linnaeus) (Diptera: Tephritidae), in North America
Rhagoletis cerasi (Linnaeus) (Diptera: Tephritidae) was reported from Mississauga, Ontario, Canada. Acknowledgements of the individual’s identity for the initial detection, as well as her contributions, were not included
Entomopathogenic fungi as a new strategy to control the European cherry fruit fly Rhagoletis cerasi Loew (Diptera: Tephritidae)
The European cherry fruit fly, Rhagoletis cerasi Loew (Diptera: Tephritidae), is a highly destructive pest of sweet cherries in Europe. Up to 100% of the fruit can be infested. Methods for controlling this pest are limited in organic agriculture as well as in integrated production, as the insecticide currently used (Dimethoate) is being challenged due to problems of ecotoxicity and residues. Alternative methods for cherry fruit fly management are therefore needed. The aim of this thesis was to develop a new control strategy for R. cerasi using entomopathogenic fungi.
In a first step, the effects of six fungus isolates on the mortality of different life stages of R. cerasi were assessed in a series of laboratory experiments. All fungus isolates caused mycosis in R. cerasi larvae and adults. These results are the first evidence of the susceptibility of R. cerasi to infection with hyphomycetous fungi. Because the flies for the laboratory experiments were collected from different locations in northwestern Switzerland, susceptibility to entomopathogenic fungi can be assumed for the cherry fruit fly population in the whole region. Although all fungus isolates tested were pathogenic to adults and larvae, virulence varied considerably among fungus isolates and R. cerasi life stages. The effects on L3 larvae were negligible; none of the fungus isolates induced mortality in more than 25% of the larvae. In contrast, adult flies were found to be highly susceptible to all fungus isolates (Metarhizium anisopliae 714, M. anisopliae 786, Isaria fumosorosea 531, I. fumosorosea Apopka 97 and Beauveria bassiana ATCC 74040) except Isaria farinosa 954. The high mortality of 90 to 100% induced by B. bassiana and I. fumosorosea during the pre-oviposition period led to significantly reduced oviposition. Higher conidia concentrations generally led to higher mortality. B. bassiana was the most effective isolate at low concentrations. Young flies showed lower mortality rates than older flies, but effects on egg eclosion rate were greatest young flies treated zero to one day after emergence. A fly-to-fly conidia transmission could not be proven after treatment of flies with a conidia suspension. Soil treatments with entomopathogenic fungi to infect emerging flies were also effective. Although the adult emergence rate was not reduced, flies emerging from treated soil showed a mortality of 42 to 83%. The oviposition rate was thus reduced by 29 to 73%, depending on the fungus isolate.
In a second step, different field application strategies were considered: soil treatments with entomopathogenic fungi to control emerging adults, the use of auto-inoculative devices for attract-and-kill strategies, and on-plant application as mycoinsecticides. Because the two American cherry fruit fly species Rhagoletis indifferens and Rhagoletis cingulata were introduced in Europe in the 1980s and because the isolates of entomopathogenic fungi selected for R. cerasi might show a different virulence on these species, the field experiments were accompanied by a four-year monitoring campaign for these species. The results of the campaign indicate that the population density of the American species is very low (<0.001%) in commercial sweet cherry orchards in northwestern Switzerland.
Soil treatments with biocontrol agents can only be effective if fly migration between differently treated trees is low. In order to examine the general potential of soil treatments, experiments using netting to cover the soil were conducted in two years and in two different orchards. The netting reduced fruit infestation by 91%. In addition, it was shown that the flies move only very short distances (less than 5 m) within orchards. In general, soil treatments areconsidered to be a promising strategy for controlling R. cerasi. The efficacy of soil treatments using different formulations of entomopathogenic fungi was evaluated in semi-field trials. Soil treatments with barley grain-formulated entomopathogenic fungi had no effect on fly emergence rate. However, adult mortality was significantly increased. The oviposition rate was thus reduced by up to 90%. In conclusion, the experiments provide first evidence that control of adult R. cerasi is possible with soil treatments under field conditions in temperate zones. A further development of this control strategy seems worthwhile for fungus isolates tested, B. bassiana and M. anisopliae. However, the results of the one year semi-field experiments do not allow general conclusions.
Another approach to bring the flies in contact with entomopathogenic fungi is the use of autoinoculative devices in an attract-and-kill strategy. For an effective attract-and kill strategy, however, highly attractive traps and baits are an essential prerequisite. The attractiveness of baits was therefore evaluated using yellow sticky traps in combination with different baits in field experiments in three years and in five different orchards. Although some baits were able to double the number of captured flies, the response of the flies to the various baits was low overall. More effective baits are needed in order for their application to be economical.
On-plant application of mycoinsecticides is another method for exposing the flies to entomopathogenic fungi. Foliar applications of B. bassiana (product Naturalis-L) at seven day intervals significantly reduced the number of infested fruit by 60 to 70%. Flight activity monitored by yellow sticky traps was only slightly affected by treatments. Infection of flies under field conditions was shown to be possible. The results were obtained from five experiments in two years with considerably different weather conditions and in different orchards with different flight intensities of R. cerasi. The other treatments tested (PreFeRal®WG containing I. fumosorosea and extensive application regime of Naturalis-L) were less effective. In order to evaluate a possible repellent effect of formulation additives contained in the oil-based formulation of the product Naturalis-L, laboratory, semi-field and field experiments were conducted using Naturalis-L, additives of Naturalis-L and other oil products. Observations of fly behaviour in the laboratory experiments revealed that oil products had an oviposition deterring effect: flies frequently landed on treated fruit and started their typical oviposition behaviour; however, due to the slippery, oily fruit surface, the flies were not able to penetrate the skin with their ovipositors. The rate of successful oviposition was thus reduced. Under field conditions, however, rape oil products degrade too rapidly to provide good control. For the product Naturalis-L, these results suggest a dual mode of action: (1) some flies are killed due to fungus infection and (2) sub-lethally infected and weakened flies might be overtaxed by the oily film on the fruit surface and therefore unable to oviposit.
In conclusion, the application of Naturalis-L (B. bassiana) is a suitable and economically feasible strategy for controlling R. cerasi. Naturalis-L is currently registered for cherry fruit fly control in Italy and Switzerland. For good efficacy, four treatments of 0.25% Naturalis-L with 1000 l water per hectare should be applied at seven to ten day intervals beginning five to ten days after the beginning of the flight period until seven days before harvest. In extensively managed standard trees, R. cerasi management is still difficult, and Naturalis-L applications are not recommended due to possibly insufficient fruit coverage in the upper canopy. Further research is needed to evaluate whether soil treatments with barley grain-formulated fungi could be a viable strategy for controlling R. cerasi in these orchards
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