Trap Samples Research Articles

Tracing the path of carbon export in the ocean though DNA sequencing of individual sinking particles

Surface phytoplankton communities were linked with the carbon they export into the deep ocean by comparing 18 S rRNA gene sequence communities from surface seawater and individually isolated sinking particles. Particles were collected in sediment traps deployed at locations in the North Pacific subtropical gyre and the California Current. DNA was isolated from individual particles, bulk-collected trap particles, and the surface seawater. The relative sequence abundance of exported phytoplankton taxa in the surface water varied across functional groups and ecosystems. Of the sequences detected in sinking particles, about half were present in large (>300 μm), individually isolated particles and primarily belonged to taxa with small cell sizes (<50 µm). Exported phytoplankton taxa detected only in bulk trap samples, and thus presumably packaged in the smaller sinking size fraction, contained taxa that typically have large cell sizes (>500 μm). The effect of particle degradation on the detectable 18 S rRNA gene community differed across taxa, and differences in community composition among individual particles from the same location largely reflected differences in relative degradation state. Using these data and particle imaging, we present an approach that incorporates genetic diversity into mechanistic models of the ocean’s biological carbon pump, which will lead to better quantification of the ocean’s carbon cycle.

Seasonal Flight Activity of Atylotus duplex (Walker), Atylotus thoracicus (Hine), and Stonemyia rasa (Loew) (Diptera: Tabanidae) in Connecticut, with Floral Hosts of Stonemyia Species in New England

Adults intercepted by Malaise traps of the Gressitt and Gressitt style were used to determine the seasonal flight activity of Atylotus duplex, A. thoracicus, and Stonemyia rasa at three sites in Connecticut over one or two years. In Guilford, adults of A. duplex entered two traps placed between an apple orchard and a mesic forest during four weeks in July 1996 and in four between late June and late July 1997. In an acidic bog in Norfolk, adults of A. thoracicus flew into a trap over five weeks between mid-July and mid-August 2011. Stonemyia rasa entered two traps in Guilford over four weeks between mid-August and early September 1996 and between late August and mid-September 1997. In Meriden, S. rasa was captured in two traps between an apple orchard and a field with scattered woody vegetation between late July and early September 1996. A significant female bias occurred in trap samples of A. duplex from Guilford in 1997 and of S. rasa from Guilford and Meriden in 1996. Flight periods in Connecticut are compared with others reported for northern areas. In New England, adults of Stonemyia rasa visited flowers of six plant species (four new floral hosts) in five families, and those of S. tranquilla were on seven species (six new) in six families. The most important results of this study were the first systematic sampling of A. duplex and S. rasa, the first state records of A. duplex, and the discovery of many new floral hosts for S. rasa and S. tranquilla. New information on flight periods of A. duplex and S. rasa was the direct result of examining the bycatch of traps operated for other purposes.

Comparison between window traps and pan traps in monitoring flower-visiting insects in agricultural fields.

Sampling flower-visiting insects in agricultural fields at large spatial and temporal scales is significant for understanding local insect pollinator communities. The most commonly used method, pan trap, has been criticized due to its attractant bias. A window trap (also referred to as the flight-intercept trap) is a non-attractant sampling method, which has been applied in forests and grasslands, but rarely in agricultural fields. We aim to test whether we can replace pan traps with window traps in agricultural fields by comparing species richness and species composition between the two methods, and to show whether flower-visiting insects collected in both traps can reflect flower-visiting activity recorded by camera observation. We conducted a 2-year study to compare the performance of these sampling methods in an oilseed rape field. Results showed that the relative abundance of dominant flower-visiting species was highly correlated between the window trap and the pan trap samples, while window traps caught more individuals and higher (rarefied) species richness than pan traps. The species composition of window traps was more similar to each other than that of pan traps. The proportion of honey bees (Apis spp.) collected in both traps underestimated their flower-visiting activity recorded by camera observations, while sweat bees (Halictidae) and butterflies (Lepidoptera) were overestimated. Our study suggests that the window trap has the potential to serve as an alternative sampling method of flower-visiting insects to the pan trap. However, we need to be cautious when using specimens caught in both traps as a proxy of their flower-visiting activity.

Seasonal variations of diatoms in a low-latitude mountain lake: a case study from Douhu lake-Southeast China

In the scientific literature on diatom ecology whether temperature drives changes in diatom assemblage directly or indirectly remains a subject of debate. In order to clarify the relationship between temperature and diatom assemblage composition, we focused on a region with significant seasonal changes but without a freezing period. From March 2016 to March 2018, sediment trap samples were collected monthly to monitor the seasonal succession of diatoms in Douhu Lake, in subtropical southeast China. The results show that in 2016 the variations in abundance of Aulacoseira granulata and Aulacoseira ambigua followed an obvious seasonal pattern, corresponding to the seasonal variation in water and air temperature. In 2016, the thermophilic taxon A. granulata was dominant in the warm season, and in the cold season its abundance declined, while that of A. ambigua, a taxon better adapted to cooler conditions, increased relatively. In 2017, however, there was no such typical seasonal variation. In the cold season of 2017, A. granulata did not decline and there was no significant increase in the cold-preferring A. ambigua. This was related to the large drop in the lake level associated with human activity (substantial water extraction) that occurred during the winter of 2017, which disturbed the natural seasonal fluctuation in water temperature. Thus, in 2017, while air temperature followed the regular seasonal cycle, lake water temperature did not decrease significantly in winter, which allowed A. granulata to maintain a relatively high abundance in the cold season. From these results and an extensive survey of the literature, we conclude that water temperature, more than the seasonal succession, directly drives the fluctuation in abundance of these two Aulacoseira species.

Diversity and Seasonal Occurrence of Native and Nonnative Ants (Hymenoptera: Formicidae) in Long-Term Experimental Chinese Privet (Lamiales: Oleaceae) Plots in Georgia, USA

Diversity and Seasonal Occurrence of Native and Nonnative Ants (Hymenoptera: Formicidae) in Long-Term Experimental Chinese Privet (Lamiales: Oleaceae) Plots in Georgia, USA

Performance of temperature and productivity proxies based on long-chain alkane-1, mid-chain diols at test: a 5-year sediment trap record from the Mauritanian upwelling

Abstract. Proxies based on long-chain alkane-1, mid-chain diols (diol for short) are obtaining increasing interest to reconstruct past upper ocean temperature and productivity. Here we evaluate performance of the sea surface temperature proxies (long-chain diol index (LDI), diol saturation index (DSI), and diol chain length index (DCI)), productivity and upwelling intensity proxies (two diol indices DIR and DIW and the combined diol index (CDI)), and the nutrient diol index (NDI) as a proxy for phosphate and nitrate levels. This evaluation is based on comparison of the diols in sediment trap samples from the upwelling region off NW Africa collected at 1.28 km water depth with daily satellite-derived sea surface temperatures (SSTs), subsurface temperatures, productivity, the plankton composition from the trap location, monthly phosphate and nitrate concentrations, wind speed, and wind direction from the nearby Nouadhibou airport. The diol-based SST reconstructions are also compared the long-chain-alkenone-based SST reconstructions. The alkenone SSTs correlate best with satellite SST (r2= 0.60). Amplitude and absolute values agree very well as do the flux-corrected time series averages. For the diol proxies the situation is more complicated. Diol proxies including 1,14 diols lag trade wind speed by 30 d. Since wind is nearly always from the NNE to NNW and induces the upwelling, we relate the variability in these proxies to upwelling-induced processes. Correlation with the abundance of upwelling species and wind speed is best for the NDI and the 1,14 diol-based DCI and DSI. The DIR, DIW, and CDI perform comparatively poorly. A negative correlation between DSI and wind speed may suggest that the DSI reflects wind-speed-forced upwelling-related reductions in temperature rather than irradiation-induced temperatures. The nutrient proxy NDI shows no significant correlation to monthly phosphate and nitrate concentrations in the upper waters and a negative correlation with both wind-induced upwelling (r2=0.28 and lagging 32 d) and the abundance of upwelling species (r2=0.38). It is suggested that this proxy reflects upwelling intensity rather than upper ocean nutrient concentrations. At the trap site, satellite SST lags wind-speed-forced upwelling by about 4 months. The 1,13 and 1,15 diol-based LDI-derived SSTs lag satellite SSTs by 41 d but correlate poorly (r2= 0.17). Absolute as well as flux-corrected LDI SSTs are on average 3 ∘C too high and rather reflect values prevailing during the more oligotrophic summer period. We attribute outliers to low LDI SST to 1,13 diols added during short upwelling-related events. The use of the LDI in regions with higher productivity is therefore not recommended. It appears thus that at the trap site the 1,14 diols primarily reflect conditions relating to upwelling whereas the 1,15C30 and to a lesser extent the 1,13 diols seem to reflect the conditions of the more oligotrophic ocean.

Geometrid Moth Species Richness, Distribution and Community Composition in Different Forest Types of Papua New Guinea

As the major group of herbivorous insects, moths are highly significant in natural ecosystems. In collaboration with the Papua New Guinea (PNG) multipurpose National Forest Inventory (NFI) survey, this study investigates the species richness, distribution and community composition of Geometrid moths (Lepidoptera) in PNG’s tropical forests and analyses environmental drivers of the geometrid community structure. By providing a baseline assessment of an important order of insects that can serve as an indicator for broader biodiversity, this study informs how biodiversity assessments can be better integrated into the planning of forest conservation initiatives, particularly those related to REDD+ and forest carbon offset developments. The research was conducted over 3 years at 38 NFI clusters throughout six provinces: Eastern Highlands, Western Highlands, Morobe, Madang and West New Britain and Central Province. Moths were collected from dusk to before midnight (18:00 h to 22:00 h) using a manual light trapping method for four nights per site, with a total of 152 light trap samples. Results included a total of 11,830 specimens from 1,108 morphological species from lowland and montane forests in disturbed (degraded and/or logged) and primary forests. Elevation and forest disturbance are the main variables that influence the distribution of species. Species richness was low in montane undisturbed forests compared with lowland (disturbed and primary) forests and montane disturbed forests. Species similarity between light trap samples tends to decrease as elevation increases. Geometrid moth species were arranged into two main orders of community composition according to the forest types: montane (disturbed and/or primary) forests species and lowland (disturbed and/or primary forest) species as per the samples.

DNA Metabarcoding Enables High-Throughput Detection of Spotted Wing Drosophila (Drosophila suzukii) Within Unsorted Trap Catches

The spotted wing drosophila (Drosophila suzukii, Matsumara) is a rapidly spreading global pest of soft and stone fruit production. Due to the similarity of many of its life stages to other cosmopolitan drosophilids, surveillance for this pest is currently bottlenecked by the laborious sorting and morphological identification of large mixed trap catches. DNA metabarcoding presents an alternative high-throughput sequencing (HTS) approach for multi-species identification, which may lend itself ideally to rapid and scalable diagnostics of D. suzukii within unsorted trap samples. In this study, we compared the qualitative (identification accuracy) and quantitative (bias toward each species) performance of four metabarcoding primer pairs on D. suzukii and its close relatives. We then determined the sensitivity of a non-destructive metabarcoding assay (i.e., which retains intact specimens) by spiking whole specimens of target species into mock communities of increasing specimen number, as well as 29 field-sampled communities from a cherry and a stone fruit orchard. Metabarcoding successfully detected D. suzukii and its close relatives Drosophila subpulchrella and Drosophila biarmipes in the spiked communities with an accuracy of 96, 100, and 100% respectively, and identified a further 57 non-target arthropods collected as bycatch by D. suzukii surveillance methods in a field scenario. While the non-destructive DNA extraction retained intact voucher specimens, dropouts of single species and entire technical replicates suggests that these protocols behave more similarly to environmental DNA than homogenized tissue metabarcoding and may require increased technical replication to reliably detect low-abundance taxa. Adoption of high-throughput metabarcoding assays for screening bulk trap samples could enable a substantial increase in the geographic scale and intensity of D. suzukii surveillance, and thus likelihood of detecting a new introduction. Trap designs and surveillance protocols will, however, need to be optimized to adequately preserve specimen DNA for molecular identification.

Semi-Quantitative Detection of Drosophila suzukii (Diptera: Drosophilidae) From Bulk Trap Samples Using PCR Technology.

Drosophila suzukii (Matsumura) (Diptera: Drosophilidae) is a ubiquitous global pest of several fruit crops. Trapped adult numbers are used to monitor populations and make control decisions, but differentiating D. suzukii from other trapped Drosophila spp. is laborious. We developed a real-time PCR method for specific detection and semi-quantification of D. suzukii from trap samples. The PCR assay did not amplify DNA from 29 other Drosophilidae species tested. Drosophila suzukii was detected from ≥0.96 pg target DNA and from laboratory samples containing one D. suzukii in 2000 other Drosophila spp. flies. We tested DNA stability of one D. suzukii in 100 Drosophila spp. flies in water or ethanol at 20, 25, or 30°C for 1, 4, or 7 d. Only water at 30°C for 7 d fully impaired D. suzukii DNA detectability. Substituting mouthwash for water resulted in D. suzukii detection in all samples held for 7 d at 30°C or daily fluctuating temperatures of 33/23°C. Traps with mouthwash as a drowning liquid had D. suzukii captures equal to traps with water. A calibration curve was established using samples in mouthwash containing 1/1,000-100/1,000 D. suzukii/total Drosophila spp. flies and incubated at 25°C for 7 d. The curve had a coefficient of determination (R2) of 0.9279 between D. suzukii numbers from the PCR and the true D. suzukii numbers in samples prepared in 70% ethanol. Collecting samples in mouthwash is expected to improve detection accuracy, and the qPCR method can be a useful tool to support D. suzukii monitoring and management.

Seasonal variation of fluxes of planktic foraminiferal tests collected by a time-series sediment trap in the central Bay of Bengal during three different years

Sediment trap samples from the southwestern Bay of Bengal were obtained at a water depth of about 900 m at sampling intervals of 17–27 days during three time periods (November 1988 to October 1989, December 1990 to October 1991, and January 1993 to October 1993). The planktic foraminifer abundances and assemblages of the samples were analyzed, and the factors governing the assemblages and their potential as indicators of climate and ocean processes in the sedimentary record were examined. We identified 28 species of planktic foraminifers in the samples, of which seven species accounted for more than 80% of each assemblage. The highest fluxes of planktic foraminifer tests were generally observed during the summer and winter monsoon seasons, and the lowest fluxes were observed during the intermonsoon seasons, especially from March to May. Periods of enhanced primary production during monsoons were accompanied by a sharp increase in the flux of Globigerina bulloides, whereas nutrient depletion in the surface ocean in spring led to subsurface small size plankton production and low planktic foraminifer test fluxes. The seasonality of foraminiferal assemblages and fluxes was controlled mainly by seasonal surface and subsurface primary production. The transition of abundant species from subsurface dwellers to surface ones throughout the monsoon season can be attributed to initial subsurface primary and secondary production being succeeded by enhanced surface production. The foraminiferal flux pattern differed among the three observation periods, especially in summer, because of interannual variation in the regional physical forces that induce nutrient replenishment at the surface. However, the consistent features of the flux pattern, with peaks during the monsoon seasons and minimal values in spring, suggest that our results reveal the essential, long-term flux pattern of planktic foraminifers in the southwestern Bay of Bengal.

Anthropogenic microfibres flux in an Antarctic coastal ecosystem: The tip of an iceberg?

This study describes the occurrence of anthropogenic microfibres (AMFs) found in sediment trap samples collected at 25 m water depth in an Antarctic fjord (Potter Cove, King George/25 de Mayo Island) from 2012 to 2015. During visual sorting of samples, AMFs were detected and described, and a subset was confirmed, via FTIR (Fourier transform infrared) spectroscopy, as semi-synthetic cellulosic and polyacrylonitrile polymers. Estimated flux of AMF varied from 115 to 152,750 microfibres m−2 throughout the studied period, with sizes ranging from 10 to 450 μm in length. Maximum AMFs fluxes occurred in summer months. Sediment traps allowed detecting temporal patterns of small (μm) AMFs, usually undersampled with nets or sieves, providing a new insight into microplastic pollution in Antarctica and its relation to environmental conditions.

Species Composition and Assessment of Sphingidae in Mt. Agad-Agad, Iligan City, Philippines

Sphingidae (Hawkmoth or Sphinxmoth) is a known bioindicator that is naturally affected by environmental issues such as deforestation and pollution. Members of thisfamily are widely distributed in Southeast Asia and play vital roles as indicators ofhabitat quality and biomass degradation. This study highlights the diversity and assessment of hawkmoths of Mt. Agad-Agad (Sitio Langinlanon, Barangay Puga-an)on Iligan City. Two sampling stations were established, the upper and lower Mt.Agad-Agad. Light trap sampling using 2 × 3 m2 white silk cloth and 500 watts lightbulb was established in selected points of the sampling stations. Six species belonging to four genera were recorded of which two species, Acosmeryx socrates and Polyptychus trilineatus philippinensis, were found very rare in the area. Station 2 (lowerMt. Agad-Agad) had the highest number of species recorded compared to Station 1(upper Mt. Agad-Agad). However, there is no significant difference between the two(t=0.59, critical t=2.2281, p=0.56) sampling stations in terms of species composition. Moreover, two species from the genus Ambulyx are the endemic species observed, viz, A. bakeri and A. wilemani.

Sweep netting samples, but not sticky trap samples, indicate beneficial arthropod abundance is negatively associated with landscape wide insecticide use

Abstract Insecticide use and landscape context are major drivers for the abundance of beneficial arthropods, such as predators, parasitoids and pollinators. However, the relative importance of local and landscape‐wide insecticide use is not well understood, and it is unclear to what extent impacts of insecticides on beneficial arthropod populations are moderated by landscape composition. We collected and analysed data on beneficial arthropod abundance and local and landscape‐wide insecticide use across 38 Dutch landscapes. We used regression to study the associations between beneficial arthropod abundance (response), insecticide use and landscape factors. Insects were sampled by sweep netting and yellow sticky traps in field margins (‘sampling sites’) in the summer of 2017 and 2018. We paired organic and conventional sites in the same landscape setting. We used three indicators of insecticide use: management (organic vs. conventional), Treatment Frequency Index of insecticides applied in the field adjacent to the sampling site, and the estimated landscape‐wide average quantity of insecticides applied per ha within a 1 km radius around the sampling site. Abundances of beneficial arthropods in field margins, assessed by sweep netting, were negatively associated with the estimated quantity insecticide applied in the surrounding landscape, while arthropod sampling by sticky traps did not show this relationship. Pollinator abundance was negatively associated with conventional management and with the frequency of insecticide applications in the adjacent field, while predator and parasitoid abundance did not show significant associations with local insecticide use indicators. Negative impacts of insecticide use were not moderated in more diverse landscapes with higher proportions of semi‐natural habitats. Policy implications. Insecticide impacts on arthropod populations extend beyond the fields in which they are used. Awareness of the potential landscape‐wide effects of pesticides, either through drift of pesticides or insect movement, may encourage land managers to adopt practices to reduce insecticide drift and the frequency of insecticide applications, thereby reducing the impacts of landscape‐wide exposure on arthropods that provide services to agriculture. Risk assessments of insecticides and pesticide use regulations need to account for potential spill‐over effects and consider landscape‐scale consequences associated with the source–sink dynamics of arthropods.

Protein cycling in the eastern tropical North Pacific oxygen‐deficient zone: A de novo‐discovery peptidomic approach

AbstractPeptides are identified using a de novo‐discovery approach in suspended and sinking particles from the eastern tropical North Pacific oxygen‐deficient zone (ODZ) and in a culture of a dominant autotroph from the region, the cyanobacterium Prochlorococcus. The benchmarking experiment with Prochlorococcus shows de novo peptides to be taxonomically specific, and thus of value in augmenting database‐driven approaches. Analysis of the suspended and sinking particles using the de novo‐discovery approach reveals the presence of fungal proteins in deep sinking particles that were not in our original search database, contributing to growing recognition that fungi may play important roles in marine organic matter cycling. Cyanobacterial peptides that have been post‐translationally modified were tracked to depth, where they contribute ~ 1% of the phylum‐level identifiable peptide pool in the sediment trap sample. The majority of peptides found at depth in the detrital pool are associated with membranes, indicating that cellular location is associated with early preservation within the detrital pool. Modified amino acids in sinking and suspended particles include high levels of deamidation, suggesting that partial extracellular degradation of protein could fuel observed anammox and contribute to pools of refractory organic nitrogen.

Species Composition, Local Status and Endemism of Sphingidae Moth in the two vegetation types of Mt. Musuan, Long-term Ecological Research Site, Bukidnon, Philippines

One of the biggest groups of moths in the Sphingidae family is the hawk moth, often known as the sphinx moth, a nocturnal pollinators and bio indicators. They stand out from other moths by having large wings, thick bodies, and longest tongues. There are 1,450 species of Sphinx moth all over the world and 117 of them existed in the Phillippines and Mindanao Island has 62 of them. Mt. Musuan, is one of the remarkable landmark of Central Mindanao University has been subjected to numerous studies of flora and fauna for several years. There were significant studies conducted on Hawkmoths but there were no published report about the species in this locality. This research was carried out on the two vegetation types of Mount Musuan, Maramag, Bukidnon in order to collect data on the composition, endemism, and local status of Hawkmoths. Sphinx moths were successfully collected using transects walks and light trap sampling in the two proposed vegetation sites using a white thin cloth and 500-watt light bulbs. A total of 9 genera and 14 species were recorded. The following are Acosmeryx socrates, Ambulyx bakeri, Ambulyx johnsoni, Ambulyx staudingeri, and Ambulyx wilemani. These were all endemic to the Philippines. There was 1 uncommon species and 13 common species recorded in their local status. The 14 species of sphinx moths comprised 35.7% endemism and these can be found on Mt. Musuan's two vegetation types.

CO2 emission and source partitioning from carbonate and non-carbonate soils during incubation

The accurate quantification and source partitioning of CO 2 emitted from carbonate ( i.e. , Haplustalf) and non-carbonate ( i.e. , Hapludult) soils are critically important for understanding terrestrial carbon (C) cycling. The two main methods to capture CO 2 released from soils are the alkali trap method and the direct gas sampling method. A 25-d laboratory incubation experiment was conducted to compare the efficacies of these two methods to analyze CO 2 emissions from the non-carbonate and carbonate-rich soils. An isotopic fraction was introduced into the calculations to determine the impacts on partitioning of the sources of CO 2 into soil organic carbon (SOC) and soil inorganic carbon (SIC) and into C3 and/or C4 plant-derived SOC. The results indicated that CO 2 emissions from the non-carbonate soil measured using the alkali trap and gas sampling methods were not significantly different. For the carbonate-rich soil, the CO 2 emission measured using the alkali trap method was significantly higher than that measured using the gas sampling method from the 14th day of incubation onwards. Although SOC and SIC each accounted for about 50% of total soil C in the carbonate-rich soil, SOC decomposition contributed 57%–72% of the total CO 2 emitted. For both non-carbonate and carbonate-rich soils, the SOC derived from C4 plants decomposed faster than that originated from C3 plants. We propose that for carbonate soil, CO 2 emission may be overestimated using the alkali trap method because of decreasing CO 2 pressure within the incubation jar, but underestimated using the direct gas sampling method. The gas sampling interval and ambient air may be important sources of error, and steps should be taken to mitigate errors related to these factors in soil incubation and CO 2 quantification studies.

DiversityScanner: Robotic handling of small invertebrates with machine learning methods.

Invertebrate biodiversity remains poorly understood although it comprises much of the terrestrial animal biomass, most species and supplies many ecosystem services. The main obstacle is specimen-rich samples obtained with quantitative sampling techniques (e.g., Malaise trapping). Traditional sorting requires manual handling, while molecular techniques based on metabarcoding lose the association between individual specimens and sequences and thus struggle with obtaining precise abundance information. Here we present a sorting robot that prepares specimens from bulk samples for barcoding. It detects, images and measures individual specimens from a sample and then moves them into the wells of a 96-well microplate. We show that the images can be used to train convolutional neural networks (CNNs) that are capable of assigning the specimens to 14 insect taxa (usually families) that are particularly common in Malaise trap samples. The average assignment precision for all taxa is 91.4% (75%-100%). This ability of the robot to identify common taxa then allows for taxon-specific subsampling, because the robot can be instructed to only pick a prespecified number of specimens for abundant taxa. To obtain biomass information, the images are also used to measure specimen length and estimate body volume. We outline how the DiversityScanner can be a key component for tackling and monitoring invertebrate diversity by combining molecular and morphological tools: the images generated by the robot become training images for machine learning once they are labelled with taxonomic information from DNA barcodes. We suggest that a combination of automation, machine learning and DNA barcoding has the potential to tackle invertebrate diversity at an unprecedented scale.

A rapid fungal DNA extraction method suitable for PCR screening fungal mutants, infected plant tissue and spore trap samples

Current DNA extraction methods from filamentous fungi take from an hour to a full day. These methods require buffers and tools for grinding fungal tissues. Although commercial extraction kits can reduce the amount of time spent preparing and extracting genomic DNA from fungal samples, these can be expensive.Here we describe a quick and inexpensive sonication technique to extract genomic DNA from filamentous fungi without buffer which can be used to perform PCR in under an hour. DNA was extracted from Zymoseptoria tritici, Fusarium graminearum and Botrytis cinerea in vitro cultures, Z. tritici asexual fruiting bodies and directly from spore trap tapes.

Diversity of hoverflies (Diptera: Syrphidae) in Nagarjun, Shivapuri Nagarjun National Park, Nepal

Abstract. Budhathoki N, Dhakal S, Dyola U. 2021. Diversity of hoverflies (Diptera: Syrphidae) in Nagarjun, Shivapuri Nagarjun National Park, Nepal. Biodiversitas 22: 5382-5388. Hoverflies are recognized as potential pollinators of a wide range of wild plants. This study explored the abundance and diversity of hoverflies over three different seasons from October 2018 to April 2019 in two different study sites, i.e. forest and grassland at Nagarjun of Shivapuri Nagarjun National Park, Nepal. Each site of the study area was further divided into five sampling transect stations. Hoverflies were collected from each station by using two methods as pan trap sampling and transect sweeping sampling. Overall, a total of 373 specimens representing 13 species under nine genera of two subfamilies (Syrphinae and Eristalinae) were recorded. The abundance and diversity of hoverflies varied seasonally, the maximum number of individuals and diversity were recorded from the spring season, whereas the minimum number of individuals and diversity were found in the winter season. In addition, forest habitat consists of the highest abundance and diversity of hoverflies, whereas grassland consists of the lowest abundance and diversity. The analysis done by using generalized linear modeling (GLM) revealed climatic parameters such as temperature and humidity had a varying effect on the abundance of hoverflies. However, both these parameters had not any significant influence on the number of hoverfly species.

Effects of calcium cyanamide on Collembola in a standardized field test: Part 1. Rationale and performance of the study

BackgroundA field study lasting one year was performed to study the effects of a calcium cyanamide fertiliser (trade name: Perlka®) on Collembola in order to support the terrestrial risk assessment under the REACH (Registration, Evaluation, Authorisation and Restriction of Chemicals) regulation. Due to the lack of an appropriate guidance document, the design of the study was based on the ISO Guideline 11268–3, originally developed for earthworm field studies. However, the sampling procedure was adapted accordingly by applying ISO Guideline 23611–2, i.e. taking soil core and pitfall trap samples. Two groups of four plots each were treated with 200 kg/ha and 400 kg/ha Perlka®, respectively. A third group served as a fertiliser control, i.e. it was treated with a standard urea fertiliser (172.9 kg Piagran®/ha) at the same total nitrogen rate (79.5 kg/ha) as provided by the high Perlka® application rate. The fourth group served as negative control without any fertiliser treatment and the fifth group was treated with the reference item Agriclor® (480 g a.i./L chlorpyrifos), known to be toxic to springtails.ResultsIn total 16 different Collembola species were determined. For seven species, covering all life form types, a reliable statistical evaluation was possible, which was reflected in correspondingly low MDD values in the study. A statistically significant decrease of the abundance (at least 50%) on the reference item plots compared to the untreated control was observed for six species, thus demonstrating the sensitivity of the Collembola community.ConclusionNo long-lasting effects of the Perlka® application rates could be observed for any of the Collembola species. In order to support risk assessors in both industry and authorities in the interpretation of large and complex data sets typical for field studies with chemicals, further guidance on implementation and data interpretation is urgently needed.