A historic account of the invasion of Drosophila suzukii (Matsumura) (Diptera: Drosophilidae) in the continental United States, with remarks on their identification

BACKGROUND: Drosophila suzukii is an oriental species first reported outside Asia from Hawaii in 1980. The first confirmed records for the continental United States were made in 2008 in California. The identification of this pest is difficult because very few published resources exist. RESULTS: It has since been recorded in Oregon, Washington, British Columbia, Alberta, Manitoba, Ontario, Quebec, Utah, Michigan, Wisconsin, Louisiana, North Carolina, South Carolina and Florida. Males are relatively easy to identify by the black apical wing spots and the single row of combs on the first and second tarsal segment of the fore leg. The male genitalia are also very characteristic and will aid in identifying teneral specimens. Females can be identified by the large ovipositor, which is 6–7 times as long as the diameter of the spermatheca. Immature stages can only be identified by molecular techniques. CONCLUSION: Although this species has been recorded from many US states and Canadian provinces, it has not been established in all of these places, and the main economic damage is restricted to the western part of North America. With the characters laid out in this paper, it should be possible to identify the pest with high certainty. Copyright © 2011 Society of Chemical Industry     

变温下铃木氏果蝇年龄-阶段两性生命表研究

为进一步阐明温度对铃木氏果蝇生长发育和繁殖的影响,补充铃木氏果蝇基础生物学信息,本研究在室内14~20℃、26~32℃变温条件下人工饲养铃木氏果蝇,对比不同变温条件下铃木氏果蝇的发育历期、存活率和繁殖率,并构建年龄-阶段两性生命表。结果表明:与26~32℃处理相比,14~20℃变温处理下铃木氏果蝇的各阶段发育历期、成虫寿命及产卵前期均较长。14~20℃变温处理下该虫年龄-阶段特征存活率(sxj)、年龄-特征存活率(lx)、年龄-阶段特征生殖能力(vxy)以及期望寿命(exy)均高于26~32℃处理,而繁殖力(fxj、mx)低于26~32℃处理。14~20℃变温处理下该虫的内禀增长率(rm)和周限增长率(λ)低于26~32℃处理,而平均世代周期(T)和种群加倍时间(t)高于26~32℃处理。在变温条件下,高温相较于低温更利于铃木氏果蝇的种群增长。     

Influence of edible fruit coatings on Drosophila suzukii (Matsumura) (Diptera: Drosophilidae) oviposition and development

Drosophila suzukii (Matsumura) is a highly invasive vinegar fly recently detected in the United States that severely threatens the viability of soft skinned fruit production. Insecticides mitigate some of this damage, but alternative methods to manage D. suzukii infestation are needed. We tested three edible coatings to determine if they could prevent or reduce oviposition by D. suzukii females or affect immature survivorship and development in two important host crops, blueberry and raspberry. None of the coatings prevented oviposition, but some reduced the number of eggs laid. Two carnauba wax-based coatings, PrimaFresh 45 and Raynox, dramatically reduced survivorship of immature D. suzukii in raspberries, but not in blueberries. Our results suggest that obtaining thorough, even coverage in the field will be essential if edible coatings are to be used as a management strategy for D. suzukii.     

Report of Drosophila suzukii (Matsumura) (Diptera: Drosophilidae) from the high-altitude and cold arid region of Ladakh,India

Drosophila suzukii (Matsumura, 1931) is here reported for the first time from the high-altitude and cold arid region of Ladakh, which is a Northwestern Himalayan region of India and is the second coldest inhabited place in the world. The species is emerging in the Ladakh region as a serious apricot pest, causing a considerable amount of economic loss.     

Monitoring insecticide resistance in house flies (Diptera: Muscidae) from New York dairies

House flies were collected from dairies across New York state and the levels of resistance to seven insecticides were measured using standard laboratory assays with three to five diagnostic concentrations. The highest levels of resistance were found for tetrachlorvinphos, permethrin and cyfluthrin. Although levels of resistance to methomyl were somewhat lower, they were among the highest ever reported for field‐collected house flies. Resistance to pyrethrins was limited primarily to the lowest diagnostic concentration. House flies were susceptible to fipronil at all dairies, suggesting that this material would be highly effective for fly control. The levels of resistance were similar at all the dairies, irrespective of their insecticide use, suggesting substantial movement of flies between facilities. Relative to resistance levels found at New York dairies in 1987, resistance levels had increased for permethrin, were unchanged for tetrachlorvinphos and had decreased for dimethoate. To identify a single diagnostic concentration that could be used in the laboratory assays to assess accurately resistance levels in future studies, we carried out a ‘simulated’ field bioassay using formulated materials. A diagnostic concentration for each insecticide is proposed on the basis of a comparison of our bioassays. © 2001 Society of Chemical Industry     

Field evaluation of commercial plant extracts against Drosophila suzukii (Diptera: Drosophlidae) in raspberry

Drosophila suzukii (Matsumura) (Diptera: Drosophilidae) was detected in 2008 in southern Europe and North America and it has spread rapidly throughout the two continents mainly affecting thin-skinned berries and stone fruits which constitute an important, economic and social driver in these regions. This study analyzes the potential control ability of four commercial plant-derived extracts, namely Sophora flavescens (shrubby sophora), Cinnamomum zeylanicum (cinnamon), Capsicum frutescens (chili) and Allium sativum (garlic), against D. suzukii, under raspberry high tunnel field conditions. Extracts were applied in a randomized complete block design using spinosad as positive control. As expected, spinosad treatment resulted in a satisfactory control, reducing significantly the number of larvae and adults emerged from treated fruits even ten days after application. Sophora flavescens extract produced a significant reduction of 60.7% in emerged adults, with no reduction in the number of larvae, six days after application. In addition, garlic extract caused significant reduction in the mean number of larvae (over 50%) and emerged adults (over 48%) six days after application. These findings suggest that garlic and S. flavescens affect egg viability and/or larvae development. Tentative explanations about the variability of the results and possible benefits of repetitive treatments are discussed.     

Management of insecticide resistance in Oriental fruit moth (Grapholita molesta; Lepidoptera: Tortricidae) populations from Ontario

The development of resistance in the Oriental fruit moth, Grapholita molesta (Busck) to organophosphorus (OP) insecticides (azinphos-methyl and phosmet) is a serious threat to the tender fruit industry in Ontario (50% crop losses in 1994). Resistance to carbamate insecticides and increased survival of field-collected moths at diagnostic concentrations of pyrethroids were widespread. As a result, four different treatment regimes were tested to manage resistance in G molesta, and the changes in resistance frequencies under each treatment regime were monitored from 1996 to 1999. The data indicated that the levels of resistance were significantly influenced by the various treatment regimes. The seasonal pattern of resistance was similar for all treatment regimes, in that resistance peaked in mid-season and declined in the late season. Levels of resistance in G molesta to OPs decreased from 55% to 14% and that to pyrethroids declined from 30% to 10% from 1996 to 1999 under a treatment regime consisting of endosulfan-organophosphate-pyrethroid rotation. Similarly, under a treatment regime implemented in commercial orchards (organophosphate-pyrethroid rotation), resistance to OP insecticides declined from 50% to 12% and resistance to pyrethroids evolved to around 16%. The overall data indicated that resistance was unstable; a strategy based on rotation of insecticides by class for each generation of G molesta was successful in managing resistance to both OP and pyrethroid insecticides. The rotational strategy has been widely adopted by growers and is applied to ca 85% of the acreage.     

Drosophila suzukii (Diptera: Drosophilidae) distribution modelling improves our understanding of pest range limits

Abstract

Spatial distributions models (SDM) are often used in invasive pest management to understand current and potential distribution. Using data on the well-studied spotted wing drosophila as a model, we compared distribution patterns of the range-limit with commonly applied correlative and mechanistic models. Correlative models risk underestimation whereas simple mechanistic models provide overestimated range predictions, although using both approaches for the spotted wing drosophila improved range-limit predictions. Model choice when dealing with pests is central to the accurate identification of invasive species limit range and consequently for the deployment of monitoring and early detection programs.     

Laboratory evaluation of fipronil,a phenylpyrazole insecticide,against adult Anopheles (Diptera: Culicidae) and investigation of its possible cross‐resistance with dieldrin in Anopheles stephensi

Adult mosquitoes from two strains of Anopheles gambiae and from three strains of Anopheles stephensi were exposed to 0.25% fipronil‐treated papers in WHO test kits or to 500 mg fipronil m⁻² impregnated mosquito netting in bioassay spheres. For comparison, tests were also carried out with the pyrethroid permethrin, using the same methods and doses, and on papers treated with 0.4 and 4% of the cyclodiene insecticide dieldrin. Compared with the same doses of permethrin, fipronil showed less and delayed activity. Two of the An stephensi strains were resistant to fipronil and dieldrin. To investigate whether this was due to a resistance mechanism in the An stephensi strains acting against both insecticides, the most fipronil‐ and dieldrin‐tolerant strain was further selected in two separate lines with one of the insecticides, followed by tests with the insecticide that the line had not been selected with. This indicated a concomitant rise of resistance to dieldrin in the fipronil‐selected line and vice versa. Repeated back‐crossing of the two lines with a susceptible strain and re‐selection with either dieldrin or fipronil gave evidence for the involvement of a single resistance mechanism to both insecticides. Permethrin resistance in both lines declined with selection for dieldrin or fipronil and confirms the absence of cross‐resistance between fipronil and pyrethroids. © 2001 Society of Chemical Industry