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Contarinia nasturtii (Kieffer) (Diptera: Cecidomyiidae), a common insect pest in Europe and a new invasive pest in North America, causes severe damage to cruciferous crops. Many counties in Canada and the USA, in which C. nasturtii has not been previously reported, are at risk of being infested by C. nasturtii. Effectiveness of chemical control is limited, especially under high population pressure in fields. Alternative management strategies against C. nasturtii are sorely needed in order to protect crucifers. Under controlled laboratory conditions, the effectiveness on C. nasturtii control by 11 simulated cauliflower-sweet corn and cauliflower-kidney bean crop rotation systems was evaluated, with and without the presence of cruciferous weeds as alternative hosts. Our results indicated that when soil was infested with C. nasturtii pupae, the emergence pattern from the soil was very similar regardless whether the soil was later planted to host or non-host plants. As emergence was not affected, we examined whether manipulating host availability for oviposition through crop rotation would be effective. Our results indicated that the simulated cauliflower-sweet corn and cauliflower-kidney bean rotation systems provided full control of C. nasturtii. The effectiveness of one cycle of non-host crop rotation was reduced when cruciferous weeds were present. However, the C. nasturtii population in a one-cycle non-host rotation system with cruciferous weeds present was significantly lower than that in a non-rotation system. Two consecutive cycles (simulating a cropping season) of non-host plant crop rotations provided full control of C. nasturtii, regardless of the presence of the cruciferous weeds. The importance of cruciferous weed management and how to implement a successful crop rotation in fields to control C. nasturtii are discussed. [ABSTRACT FROM AUTHOR]

ABSTRACT Contarinia nasturtii (Kieffer) (Diptera: Cecidomyiidae), a common insect pest in Europe and a new invasive pest in North America, causes severe damage to cruciferous crops. In the United States, C. nasturtii was first reported in western New York in 2004. From 2005 to 2007, field surveys were conducted in western New York to investigate the occurrence of C. nasturtii in weeds that might serve as a reservoir for this pest. The results indicate that 12 cruciferous weed species were found in and around commercial vegetable crucifer plantings, and C. nasturtii emergence was detected from most of them. The number of C. nasturtii that emerged from the weeds was low and varied by species, year, and the timing of sampling. Peak emergence from weeds in fallow fields occurred in June. Nonchoice tests in the laboratory showed that significantly fewer larvae were found on cruciferous weeds than on cauliflower plants, although C. nastnrtii could lay eggs on the weeds. When weeds and cauliflower plants were simultaneously exposed to C. nasturtii adults for egg laying (choice tests), 97,3% of the C. nasturtii larvae were found on the cauliflower plants 8 d after oviposition, 2.7% on Sinapi.s arvensis L., and none on the other five weed species tested. Our results suggest that cruciferous weeds can serve as alternative host plants of C. nasturtii but are less suitable than cauliflower. A method of detecting C. nasturtii on weeds and control of C. nasturtii through weed management are discussed. [ABSTRACT FROM AUTHOR]

Abstract: Swede midge (Contarinia nasturtii Keiffer) is a serious gall-forming insect pest of cruciferous plants in Europe and southwestern Asia. In North America, it was first identified in Ontario, Canada, in 2000 and in Niagara County, New York, US, in 2004. The insect is now rapidly spreading in Canada and the US. To date, infestation of C. nasturtii has been confirmed in 46 counties in Canada. The US Department of Agriculture has confirmed the presence of C. nasturtii in 6 counties in the US, although our surveys using pheromone traps have identified 19 counties in New York and one county in Massachusetts and New Jersey. Currently, hundreds of farms in the northeastern US that grow cruciferous vegetables are at risk for infestation of C. nasturtii through movement of vegetable seedlings and harvested produce from infested areas. To prevent the spread of C. nasturtii, the efficacy of acetamiprid, the first labeled insecticide in the US for C. nasturtii control, was evaluated by using foliar sprays on cauliflower seedlings. Results indicated the efficacy of acetamiprid on C. nasturtii was 99.52% 100% and 99.83% when cauliflower seedlings were sprayed before inoculation with C. nasturtii, 0 and 4d after inoculation, respectively. The efficacy of acetamiprid was reduced to 69.89% when seedlings were sprayed 8d after inoculation, and C. nasturtii larvae could successfully pupate and emerge after the spray. These results indicate that acetamiprid can effectively control C. nasturtii on cauliflower seedlings, especially in the early stage of insect occurrence. Based on these results, we suggest that seedlings be treated with acetamiprid as a foliar spray before shipment of seedlings from C. nasturtii infested areas. [Copyright &y& Elsevier]

The midge Contarinia nasturtii Kieffer (Diptera: Cecidomyiidae) was first confirmed in North America in Ontario, Canada, in 2000. The insect is now distributed throughout many counties in the provinces of Ontario and Québec. Nearly 1,200 farms in the northeastern United States that grow cruciferous vegetables are at risk for C. nasturtii infestation if this insect were to spread to that region. Over a period of 3 yr (2002-2004), ≈3,000 ha of crops on 94 farms in western New York State was scouted for C. nasturtii, but none were found. In 2004, 42 experimental pheromone traps were placed in fields of cruciferous vegetables in eight counties. C. nasturtii males were captured at low levels (1-50 per trap/8 wk) on four farms in Niagara County, but not at any other site. C. nasturtii larvae were found in plant tissue at one of the four farms. Insect specimens were identified by morphological methods, molecular methods, or both. This is the first confirmation of C. nasturtii in the United States, which we believe was made possible by the combined use of pheromone traps, morphological characters of trapped adults, and molecular methods. The early detection in New York presents an opportunity to implement measures to limit the spread and establishment of C. nasturtii across the state and into other regions of the United States. [ABSTRACT FROM AUTHOR]

Addresses controversies surrounding scientific studies on pest control in the United States. Background on the bacteria Bacillus thuringiensis; Findings of the studies; Suggestions for scientists.

The Swede midge, Contarinia nasturtii Kieffer (Diptera: Cecidomyiidae), a common insect pest in Europe, is a newly invasive pest in North America that constitutes a major threat to cruciferous vegetable and field crops. Since its first identification in Ontario, Canada, in 2000, it has rapidly spread to 65 counties in the provinces of Ontario and Quebec and has recently been found in canola (one of two cultivars of rapeseed, Brassica napus L. and Brassica campestris L.) in the central Prairie region where the majority of Canada's 6.5 million ha (16 million acres) of canola is grown. The first detection of Swede midge in the United States was in 2004 in New York cabbage (Brassica oleracea L.), but it has now been found in four additional states. Here, we review the biology of Swede midge, its host plant range, distribution, economic impact, pest status, and management strategies. We provide insight into this insect's future potential to become an endemic pest of brassica crops in North America. We also proposed research needed to develop tactics for handling this invasive pest in brassica crops.