Search Results (150)

Common methods for detecting Drosophila suzukii (spotted-wing drosophila, SWD) in fruit, such as microscopy, physical extraction, and incubation, are time-consuming and may underrepresent egg and first instar larvae counts, the smallest life stages of SWD. To address these limitations, we evaluated a quantitative real-time PCR (qPCR) protocol to detect and quantify SWD eggs using a linear model of the log-transformed ratio of eggs to sample volume (µL) in Tris buffer and fruit tissue. Compared to traditional approaches, this method reduces identification time from several weeks to approximately five hours. We observed a negative linear correlation between qPCR cycle threshold and egg concentration in both standard and fruit tissue samples, with similar model fits (R² = 0.7215 for field fruit tissue; R² = 0.874 for standard samples). This DNA-based protocol improves infestation detection speed and accuracy by enabling rapid, species-specific identification of D. suzukii in fruit tissue, addressing limitations of morphological identification of eggs and larvae. Further refinement for fruit tissue could enhance real-world applicability. Rapid detection may enable timely assessment of varietal resistance to SWD and support safer control strategies targeting early life stages, helping to prevent pest development and fruit degradation. Full article

In this study, we investigated the current and future potential distribution of three parasitoid species of Drosophila suzukii, which represent promising candidates for the biological control of this pest: Leptopilina japonica (Hymenoptera, Figitidae), Pachycrepoideus vindemmiae (Hymenoptera, Pteromalidae), and Trichopria drosophilae (Hymenoptera, Diapriidae). To this end, we employed Ecological Niche Modeling using the Random Forest algorithm and climatic data from WorldClim v. 2.1 under climate change scenarios (SSP2-4.5 and SSP5-8.5), analyzing the spatial overlap between the pest and its natural enemies. The results indicate that the parasitoids exhibit distinct geographic distributions, although most species show higher suitability for temperate regions of the Northern Hemisphere. Species such as T. drosophilae and L. japonica stand out for their broad distribution and high overlap with the pest, whereas P. vindemmiae and display more restrictive climatic ranges and lower control efficiency. With ongoing climate change, all parasitoids tend to migrate toward higher latitudes, with significant range contractions in tropical regions. Thus, our results demonstrate the usefulness of Ecological Niche Modeling in the selection of biological control agents by considering host-specific preferences and environmental requirements in the development of management strategies adapted to future scenarios. Full article

Several fruit fly species in the Drosophilidae and Tephritidae families are classified as invasive pests worldwide. However, limited information is available on the occurrence of those dipteran species, their interactions, and their host plants in the Pampa Biome of southern Brazil. Therefore, we investigated interactions between invasive fruit flies and host plants. After two years (2022–2023) of fruit surveys, 3802 fruits from 16 plant species were harvested in the Pampa Biome’s urban and rural areas. The collected fruits were conditioned in the laboratory. Emerged adult flies were identified and associated with the respective fruit species. The most abundant species detected were Zaprionus indianus (Gupta), followed by Zaprionus tuberculatus (Malloch), Drosophila suzukii (Matsumura), and Ceratitis capitata (Wiedemann). The invasive drosophilids D. suzukii, Z. indianus and Z. tuberculatus interacted with 10 host plant species each, whereas C. capitata was associated with seven host species. Zaprionus indianus showed the highest infestation rate on fruits collected from the ground, whereas D. suzukii had the highest infestation rate in fruits attached to plants. New host plants were identified for Z. tuberculatus and C. capitata. The findings of this study provide a valuable framework for more effective management and control strategies. Full article

The increase in the world population and consequent rise in food demand have led to the extensive use of chemical pesticides, causing environmental and health concerns. In response, biological control methods, particularly those involving microbial agents, have emerged as sustainable alternatives within integrated pest management. This study highlights the potential of Lysinibacillus fusiformis as a biocontrol agent against the dipteran Drosophila suzukii (Matsumura) (Diptera: Drosophilidae), a pest responsible for damaging soft-skinned fruits. Experimental treatments using vegetative cells, spores, and secondary metabolites of L. fusiformis on D. suzukii larvae demonstrated significant larvicidal effects, accompanied by observable changes in gut morphology under microscopy. Moreover, preliminary immunological assays showed the interference of this bacterium with the host immune system. All the results indicate the suitability of L. fusiformis for its possible integration into sustainable agricultural practices, although additional research is required to understand its applicability in the field. Full article

Drosophila suzukii is a key invasive pest, and infestation in peach orchards can lead to significant economic losses. This study monitored the spatial distribution and reproductive biology of D. suzukii in central Italy to inform integrated pest management (IPM) strategies. In the surveyed orchard, the pest exhibited multiple generations, with captures highest along mixed-species-orchard edges, highlighting these margins as potential hotspots for targeted mass trapping. Seasonal dissections of females revealed delayed ovarian development during winter, while maturation progressed during fruit ripening and post-harvest periods. This result provides relevant information on the likely timing of oviposition, useful for informing pest management. A laboratory oviposition trial on nectarines revealed a clear preference for healthy, mechanically damaged fruits, whereas fungal infection reduced the attractiveness. This suggests that field sanitation, especially the timely removal of damaged or fallen fruits, could reduce pest presence and inoculum for the following season. Overall, these findings offer practical insights to support sustainable IPM approaches against D. suzukii in peach production systems. Full article

Gene duplications are considered to be the major evolutionary resource of novel functions. The gene family Esf2/ABP1 is conserved in metazoan organisms from yeast to humans. Here we performed a search and characterization of Esf2/ABP1 homologs in the Drosophila genus. Whereas in the majority of Drosophila species this gene family is represented by only a single gene, in the melanogaster and suzukii subgroups recurrent gene duplications arose, providing 47 homologous genes located on the X chromosome. To study the evolutionary history of duplicates, we performed phylogenetic, functional domain, and tissue-specific expression analyses. We revealed a male-specific and testis-biased transcription pattern of duplicated copies in Drosophila melanogaster and Drosophila sechellia compared to ubiquitous expression of the parental gene. The amplification of 21 repeated paralogs within the heterochromatic piRNA cluster resulted in the ovarian-specific transformation of these repeats into piRNAs in D. melanogaster. In three species of the suzukii subgroup, Esf2/ABP1 genes evolved with domain diversification: in addition to RNA-binding ABT1-like domain preservation, all homologous proteins acquired expanded intrinsically disordered regions. By studying the duplicated copies of the Esf2/ABP1 family in Drosophila, we offer insight into how novel gene functions emerge and are maintained, contributing to life’s diversity and complexity. Full article

Drosophila suzukii is an invasive pest of many fruit crops worldwide. Employing the Sterile Insect Technique (SIT) could mitigate D. suzukii population growth and crop damage. This study evaluated the efficacy of SIT on commercial fruit, by (1) validating the quality of irradiated sterile males (male mating competitiveness, courtship, and flight performance) in the laboratory, and (2) assessing population suppression and fruit damage reduction in commercial raspberry fields. Treatment with SIT was compared to the grower’s standard chemical insecticide program throughout the season. The principal metrics of efficacy were trap counts of wild adult female D. suzukii in crops and larvae per fruit during harvesting. These metrics together with monitoring of border areas allowed targeting of high-pressure areas with higher releases of sterile males, to maximise efficacy for a given release number. The sterile male D. suzukii were as competitive as their fertile non-irradiated counterparts in laboratory mating competitiveness and flight performance studies while fertility egg-to-pupae recovery was reduced by 99%. In commercial raspberry crops, season-long releases of sterile males significantly suppressed the wild D. suzukii population, compared to the grower standard control strategy; with up to 89% reduction in wild female D. suzukii and 80% decrease in numbers of larvae per harvested fruit. Additionally, relative fruit waste (i.e., percentage of harvested fruits rejected for sale) at harvest was reduced for early, mid and late harvest crops, by up to 58% compared to the grower standard control. SIT has the potential to provide an effective and sustainable strategy for managing D. suzukii in raspberries, increasing marketable yield by reducing adult populations, fruit damage and waste fruit. SIT could therefore serve as a valuable tool for integrated pest management practices in berry production systems. Full article

Drosophilidae is a relatively small family within Diptera. However, species of this family occupy a wide range of ecological niches and are frequently found in synanthropic habitats. Additionally, some species are known agricultural pests. The dataset is based on collections of Drosophilidae from eleven regions of Russia. The dataset was uploaded to the GBIF platform in 2024. Published sources specifying exact localities and collection dates were also used. The database includes records dating back to 1867, with the majority of specimens collected by the authors between 2001 and 2024. Collection methods included net sweeping and bait trapping. The dataset contains 2830 occurrence records, with a total of 51,006 specimens of Drosophilidae studied. It includes data on 108 species from two subfamilies, covering 49 regions of Russia. Considering additional published sources, 188 species of Drosophilidae are currently known from Russia, with a complete species list provided. Among the most abundant species in the dataset, 10 species are represented by more than 1000 specimens: Drosophila obscura, Scaptodrosophila rufifrons, Drosophila melanogaster, Drosophila phalerata, Drosophila transversa, Drosophila kuntzei, Drosophila histrio, Drosophila testacea, Phortica semivirgo, and Drosophila immigrans. Conversely, 39 species are represented by fewer than 10 specimens in the dataset. Regarding ecological groupings, the most dominant groups are xylosaprobionts (39 species, 40.6%) and mycophages (30 species, 31.3%). Notably, in 2017, the quarantine pest Drosophila suzukii was detected in the European part of Russia. The current knowledge of the Drosophilidae fauna in Russia remains insufficient. Of the 15 regions, only one or two localities are represented in the dataset. The distribution limits and range boundaries of many species remain unknown. Moreover, the local faunas of more than half of Russia’s regions remain unexplored. Full article

The spotted wing drosophila, Drosophila suzukii is an injurious polyphagous pest threatening worldwide soft fruit production. Its high adaptability to new colonized environments, short life cycle, and wide host range are supporting its rapid spread. The most common techniques to reduce its significant economic damage are based on multiple insecticides applications per season, even prior to the harvest, which reduces agroecosystem biodiversity and affects human and animal health. Environmental concerns and regulatory restrictions on insecticide use are driving the need for studies on alternative biological control strategies. This study aimed to assess the effect of T. drosphilae in controlling D. suzukii infestations and its interaction with P. vindemiae, a secondary parasitoid naturally present in Apulia (South Italy). Field experiments were carried out in organic cherry orchards in Gioia del Colle (Bari, Italy) to test the efficacy and adaptability of T. drosphilae following weekly releases of artificially reared individuals. Additionally, the interaction between P. vindemiae and T. drosphilae was studied under laboratory conditions. Results from field experiments showed that D. suzukii populations were significantly lower when both parasitoids were present. However, T. drosophilae was less prone to adaptation, so its presence and parasitism were limited to the post-release period. Laboratory experiments, instead, confirmed the high reduction of D. suzukii populations when both parasitoids are present. However, the co-existence of the two parasitoids resulted in a reduced parasitism rate and offspring production, notably for T. drosophilae. This competitive disadvantage may explain its poor establishment in field conditions. These findings suggest that the field release of the two natural enemies should be carried out with reference to their natural population abundance to not generate competition effects. Full article

Drosophila suzukii, classified as a quarantine pest in some countries, poses a serious threat to global trade due to its ability to damage berries and cherries. Recent studies indicate that low-temperature phosphine (PH₃) fumigation effectively controls this pest without compromising fresh produce quality. However, the specific protocol for managing D. suzukii larvae in cherries using this method remains underexplored. This study evaluates the efficacy of low-temperature PH₃ fumigation in controlling D. suzukii larvae across three cherry varieties at 3 °C and investigates potential effects on key quality metrics. Tolerance assessments revealed that 3rd instar larvae exhibit the highest resistance to PH₃ among all developmental stages. A concentration of 800 mL/m³ PH₃ for 84 h at 3 °C achieved phytosanitary efficacy for 0.99997 with no negative effect on the quality attributes of the tested cherry varieties. These results support low-temperature PH₃ fumigation as a viable postharvest treatment for D. suzukii management in sweet cherries. Full article

Drosophila suzukii is a successful invasive insect species responsible for agricultural losses. The key to its prowess is the ability to swiftly adapt to new environments through various genetic mechanisms, including fast accommodation of mutations and gene expression fine-tuning. Piezo and nanchung (nan) genes are linked to circadian clock-related behaviors and, therefore, are expected to readily respond to stress stimuli. Herein, we compared the DNA sequences of Piezo, nan, and αTubulin at 67C, a highly conserved housekeeping gene, in ICDPP-ams-1, a Romanian local population of D. suzukii, and two well-annotated reference populations from the United States of America and Japan. Our results imply that short-term evolutionary accumulated single nucleotide and indel variants are overrepresented within introns, a propensity evaluated through the mutation accumulation tendency (MAT) original parameter. Piezo and nan gene expression under photoperiodicity changes challenges were assessed in a series of experiments on three groups of individuals from ICDPP-ams-1. We found that both genes are upregulated in females if their customary circadian rhythm is affected, a trend seemingly reverting if, after an initial perturbation, the circadian clock is reset to its initial timing. In conclusion, we found that both highly conserved and adaptability-related genes are rapidly evolving and that Piezo and nan have a fast functional reaction to circadian clock changes by modifying their gene expression profiles. Full article

The invasive spotted wing Drosophila (SWD) represents new challenges for European and North American fruit producers. The aim of our study was to examine wine grape cultivar susceptibility to this pest and melanogaster-type Drosophila (MTD) by surveying drosophilid populations using field traps and conducting emergence tests. We assessed fly development from intact and artificially injured berries collected from four cultivars. Berries were incubated individually and in pooled samples to evaluate infestation patterns and potential larval interactions. Although grapes are generally considered less favorable hosts for SWD, the pest was consistently present across all vineyard plots. Infestation levels differed significantly among cultivars, with the Hungarian white cultivar Furmint being the most susceptible, while French-origin red cultivars Cabernet Franc and Cabernet Sauvignon, along with the other Hungarian cultivar Rózsakő, were less susceptible. Berry integrity played a crucial role: intact berries showed minimal infestation, whereas physical injuries led to a substantial and significant increase in infestation rates and fly emergence. In contrast to SWD-dominated trap catches and the nearly equal proportions of SWD and MTD observed in intact berries, injured berries were predominantly colonized by MTD. This dominance became even more pronounced in pooled samples, suggesting that larval competition in shared environments favors MTD over SWD. These findings underscore the importance of grape cultivar traits and berry condition in shaping Drosophila infestation dynamics. Further research into the chemical and ecological drivers of host selection and interspecific interactions is warranted to improve vineyard pest management strategies. Full article

Drosophila suzukii (Matsumura) is a relevant pest affecting berries and stone fruits globally, including in the Neotropical region, where its invasion was reported about a decade ago. Despite chemical control being the main management method for D. suzukii, data on insecticide susceptibility in Neotropical D. suzukii populations are scarce. Here, we assessed the susceptibility of three field-collected Brazilian D. suzukii populations to four insecticides (i.e., deltamethrin, permethrin, spinetoram, imidacloprid) and contrasted this with a standard insecticide-susceptible population. Using the discriminating concentration (LC₉₀) from the standard susceptible population, we identified resistant populations. Synergist exposure (piperonyl butoxide, triphenyl phosphate, diethyl maleate) indicated the role of detoxification enzymes in resistance. Our results showed that deltamethrin was the most toxic, followed by spinetoram, permethrin, and imidacloprid. While all field populations were similarly susceptible to pyrethroids and spinosyns, one population from Minas Gerais (i.e., Paula Candido) had significantly lower imidacloprid susceptibility, with only 53.4 ± 5.2% mortality at 10.0 g/L (the equivalent of 10-fold the estimated imidacloprid LC₉₀). Only piperonyl butoxide increased the imidacloprid susceptibility of Paula Candido flies. Our findings indicate the occurrence of cytochrome P450 enzyme-based imidacloprid resistance in the state of Minas Gerais, which can challenge the management of D. suzukii in Brazil. Full article

Spotted wing drosophila (SWD), Drosophila suzukii (Diptera: Drosophilidae), are invasive vinegar flies of East Asian origin that are an increasingly global threat to the small fruit industry. It is essential that new classes of eco-friendly insecticides and cost-effective strategies for SWD control are developed. Here, we describe the preparation of a strain of RNA interference (RNAi) Saccharomyces cerevisiae expressing shRNA that specifically targets the SWD RNA-binding Fox protein 1 (Rbfox1) gene. The yeast effectively silences the SWD Rbfox1 gene, resulting in significant loss of fly neural activity. Laboratory trials demonstrated that the RNAi yeast can be mixed with soda, which functions as SWD attractive targeted sugar bait (ATSB) that can be delivered in a soda bottle feeder. The ATSB, mixed with yeast that was heat-killed prior to suspension in the ATSB, resulted in 92 ± 1% mortality of SWD flies that consumed it, yet had no impact on non-target dipterans. Rbfox.687 yeast delivered in ATSB feeders may one day be a useful component of integrated SWD control programs. Full article

Trichopria drosophilae is a globally distributed pupal parasitoid that targets various species within the Drosophilidae family, including the invasive Drosophila suzukii. The mass rearing of T. drosophilae is a crucial step in ensuring their successful application for field D. suzukii control. The pupae of Drosophila melanogaster are currently used as a host for the mass rearing of T. drosophilae. After irradiation, the immune system function of Drosophila pupae was weakened, leading to an increase in the parasitism efficiency of the T. drosophilae. Our results showed that irradiated pupae had a significant impact on the parasitism rate, offspring eclosion rate, offspring number, and female body size of F1 T. drosophilae, all of which were significantly lower than those in the normal group. However, there was no significant difference in the parasitism rate, body size, offspring eclosion rate, offspring number, or offspring sex ratio between F2 T. drosophilae emerging from treated or untreated Drosophila pupae. Compared with F2, F1 had a significantly higher net reproductive rate (R₀), mean generation time (T), and doubling time (DT), while the intrinsic rate of increase (r) was significantly lower. Using irradiated D. melanogaster pupae provides an efficient method for the mass rearing of T. drosophilae and offers valuable insights into its potential effectiveness in field D. suzukii control. Full article