Spatial and temporal genetic variation of Drosophila suzukii in Germany

Native to Southeast Asia, the spotted wing drosophila (SWD), Drosophila suzukii Matsumura, rapidly invaded America and Europe in the past 20 years. As a crop pest of soft-skinned fruits with a wide range of host plants, it threatens the fruit industry worldwide, causing enormous economic losses. To control this invasive pest species, an understanding of its population dynamics and structure is necessary. Here, we report the population genetics and development of SWD in Germany from 2017–19 using microsatellite markers over 11 different sample sites. It is the first study that examines SWD’s genetic changes over 3 years compared to multiple international SWD laboratory strains. Results show that SWD populations in Germany are highly homogenous without differences between populations or years, which indicates that populations are well adapted, migrate freely, and multiple invasions from outside Germany either did not take place or are negligible. Such high genetic variability and migration between populations could allow for a fast establishment of the pest species. This is especially problematic with regard to the ongoing spread of this invasive species and could bear a potential for developing pesticide resistance, which could increase the impact of the SWD further in the future.

     

Plastic mulches reduce adult and larval populations of Drosophila suzukii in fall-bearing raspberry

Journal of Pest Science - The invasive spotted-wing drosophila, Drosophila suzukii, is a major pest of fruit crops worldwide. Management of D. suzukii relies heavily on chemical control in both...     

Fruit volatiles mediate differential attraction of Drosophila suzukii to wild and cultivated blueberries

Journal of Pest Science - Native to the northeast USA, highbush blueberry is a crop domesticated for close to 100 years and that has been selected mainly for high yields and bigger fruit....     

Correction to: Plastic mulches reduce adult and larval populations of Drosophila suzukii in fall‑bearing raspberry

Journal of Pest Science -     

Efficacy of spinetoram as a contact insecticide on different surfaces against stored-product beetle species

Contact toxicity of spinetoram was evaluated in laboratory bioassays on concrete, ceramic tile, galvanized steel, and plywood. The efficacy of spinetoram was assessed at dose rates of 0.025 mg (AI)/cm², 0.05 mg (AI)/cm², and 0.1 mg (AI)/cm² in two series of bioassays. The first series was conducted on concrete surfaces, with adults of Rhyzopertha dominica (F.), Sitophilus oryzae (L.), S. granarius (L.), Tribolium confusum Jacquelin du Val, Oryzaephilus surinamensis (L.), and Cryptolestes ferrugineus (Stephens). The second series was conducted at the same dose rates on all surfaces against adults of R. dominica, S. oryzae, and T. confusum. An equal number of dishes with and without food were used in both bioassay series. Mortality was assessed daily for 7 days for T. confusum and after this interval all live adults were removed and transferred to untreated surfaces with food and held under the same conditions. After the first week of daily evaluation, delayed mortality was evaluated 7 days later. For all the other species, mortality was measured after 5 days of exposure. The results of the first series of bioassays showed that T. confusum was the least susceptible to spinetoram-treated concrete surfaces. In contrast, all the other species were found susceptible, regardless of the dose and the presence of food. Regarding the comparison of different surfaces, our results illustrate that, with the exception of T. confusum, there were no significant differences among surfaces. The results of the present study indicate that spinetoram was effective against various species on several types of surfaces, and the presence of food did not influence its efficacy in most cases.     

Hydraulic drive and control system of the cone collecting robot

BasicstructureoftherobotThebasicstructureoftherobotincIudesthreeparts'pickingmanipuIator,runningpart(crawIertractor),computernumericalcontroIsystem.TheshapeofthemanipulatoroftherobotwasshowninFig.1.ThemanipuIatorhastWo6-mlongarms.onthetopoftheforearm,therearetWotooth-likepickingcombs,O.5minwidthando.85minlength,madeof6oSi2MnsteelandweredrivenbythehydrauIicsystem.Thecombscanswayleftandright,turnupanddown,andcanopenandcloseliketooth.Fig.1.GeneralstruCtureoftherobot1.Machineffamei2.Rotaryd…     

Carbon emissions due to land-use change and logging in Cambodia: a modeling approach

Land-use change and forestry in the tropics have caused huge carbon emissions to the atmosphere. The magnitude of these emissions, however, remains debatable. Therefore, there is a need to further develop appropriate methods that would reduce the estimation uncertainties. From a modeling perspective, this report is aimed at estimating carbon emissions from deforestation and logging activities in Cambodia just after it opened its door to the world. Recently available land-use and forest inventory data were used to develop simple models capable of estimating the change of carbon stocks in, and carbon emissions from, dryland and edaphic forests. This study estimated the annual deforestation rate to be 0.1 million ha between 1973 and 2003, or about 0.7%. Between 1993 and 2003, annual carbon emissions amounted to about 13.7 TgC, owing to deforestation and logging. The emissions calculated here are higher than those reported by the Cambodian government, which claimed that Cambodia was once a net sink of carbon. The models developed in this study will be a useful tool for further study of carbon emissions in tropical countries where selective logging is practiced. Part of this article was presented at the International Symposium on the Role of Forests for Coming Generations: Philosophy and Technology for Forest Resource Management, October 2004, Utsunomiya, Japan