The investigations were financially supported by the Division for Earth and Life Sciences of the Netherlands Organization for Scientific Research (grant 833.13.004), the Sci-Tech Landing Projection of Higher Education of Jiangxi Province (KJLD14030) and The Cultivation Plan for Young Scientists of Jiangxi Province (Jinggang star 20153BCB23014). We thank Daomeng Fu, Zhigang Li and Xiaolong Huang for their help in producing the movie.

1. Modification of a Leaf Blower-vac for Suction Sampling
<ol>
	<li>Collect all parts listed in the Materials List.</li>
	<li>Connect all polyvinyl chloride (PVC) pipes with unplasticized polyvinyl chloride (U-PVC) glue (pipes 1-2-3-4-5 and 6-7).</li>
	<li>Drill three holes that are evenly distributed around the suction mouth of the machine.</li>
	<li>Connect the machine to the end 1 of PVC pipe 1-5 by inserting one screw into each of the three holes. Do not use glue to connect pipe end 1 to the machine because the connection should be reversible to clean the fan. 
	Note: In case the diameter of the suction mouth of the machine differs from the model described here, the diameter of pipe end 1 should be adjusted to fit the machine seamlessly.</li>
	<li>Add 2 layers of thread seal tape to pipe ends 5 and 6.</li>
	<li>Put the piece of metal gauze between the hose and the mouth part (PVC pipes 6 and 7) to prevent the sampling net from being sucked into the machine. Use metal gauze with a mesh diameter between 0.5 mm and 0.5 cm.</li>
	<li>Connect the hose to pipe ends 5 and 6 with metal clamp hoops.</li>
</ol>
2. Prepare the Sampling Enclosure
<ol>
	<li>Remove the bottom from a plastic bucket (50 L, 40 cm bottom diameter). This size of the enclosure covers 2-4 rice hills in a&#160;transplanted rice field, depending on crop stage24.</li>
	<li>Attach a nylon mesh sleeve, with a length of 1 m, to the top of the bucket using a rubber band. For this sleeve, use a mesh size that is small enough to prevent the escape of the smallest target arthropods. Use a diameter less than 0.5 mm.</li>
</ol>
3. Field Application of the Modified Leaf Blower-vac for Suction Sampling
<ol>
	<li>Use two persons to operate the device in the field. One person operates the blower-vac and the other handles the bucket enclosure and the sampling nets.</li>
	<li>Start the machine.</li>
	<li>Insert a sampling net into the mouth part of the blower-vac and fix it with a rubber band. For the net, use a mesh size that is small enough to catch the smallest target arthropods, but does not create obvious airflow resistance. Use the light nylon material with a mesh diameter between 0.2-0.5 mm.</li>
	<li>Place the enclosure quickly over the plants at a random location in the field and push the bottom of the bucket firmly into the soil. Make sure that the sleeve is closed to prevent arthropods from escaping from the top of the enclosure.</li>
	<li>Remove all arthropods from inside the enclosure in a top-down spiraling way, for a standardized sampling duration. For rice crops in the vegetative and reproductive stages, use sampling durations of 1 and 2 min, respectively.</li>
	<li>After finishing the sample, remove the rubber band from the sampling net, quickly close the net and take it out of the mouth part of the blower-vac and close it with a knot, while keeping the machine running.</li>
	<li>Repeat steps 3.2 to 3.5 at random locations in the field for the next samples. The number of replications depends on the variation in the spatial distribution of arthropods in the field, the required accuracy of the estimate and the purpose of the study. Typically, six replicates will give a good impression of the arthropod community and species abundances.</li>
</ol>

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The authors have nothing to disclose.

Suction sampling is one of many possible methods to sample arthropod communities in crops. For scientific research in rice systems, suction sampling is an appropriate option because the method provides absolute estimates of arthropod densities, it is non-destructive, and &#8212; in contrast to visual counts &#8212; allows collection and storage of samples for later processing. Compared to the commercially available D-vac, the blower-vac is smaller, lighter and easier to handle in (flooded) rice fields and also easier to combine with an enclosure. For example, a blower-vac weighs about 6 kg, whereas the backpack D-vac model, presented as the international standard for insect sampling, has a weight 12 kg11. More importantly, the sampling efficiency of the blower-vac is higher than the D-vac16,17, while the cost of the blower-vac is less. The modification of a leaf blower-vac into a suction sampler does not require special skills or equipment and takes less than an hour after all additional parts have been collected. The blower-vac described here is easier to construct and operate than versions described previously in the literature16,17, and the required parts (Table 1) are standard construction materials that are widely available. This makes the blower-vac also accessible to researchers with small budgets in developing countries.
The power and displacement of the engine determines the suction force of the blower-vac. Here we recommend a machine with a power between 0.7-1.2 kW and a displacement between 25-35 cc, which is adequate for sampling the plant-dwelling arthropod community in rice. The length of the flexible plastic hose and the diameter of the sucking mouth part (pipe 7) are critical for a good sampling performance. A hose that is too long will reduce the suction power, whereas a hose that is too short will be inconvenient to use during sampling. Similarly, a mouth part with too large a diameter will reduce the suction power, whereas a diameter that is too small will reduce the sampling efficiency due to the small surface. The sampling efficiency depends critically on the sampling duration. If sampling is conducted throughout the growing season, the sampling duration may have to be adjusted to the plant size, structure, and planting density to maintain a similar level of efficiency. Sampling efficiency should be checked by careful visual inspection of the enclosed area after sampling. If there are still arthropods present, the sampling duration must be increased. The recommended sampling durations for rice crops in the vegetative stage is 1 minute&#160;and in the reproductive and ripening stages it is 2 minutes.
Suction sampling with the blower-vac can be conducted in flooded fields, while alternative methods, such as pitfall and beat sheet sampling are not feasible in standing water. The blower-vac can also be used to sample the arthropod community on the water surface of flooded rice fields (e.g., predatory water bugs), as the machine is capable of sucking in some water. However, it is not recommended for sampling aquatic arthropods as the motor may stop running when the mouth part is inserted deeply into the water and the airflow is blocked. Apart from rice, the blower-vac can also be used in other crops and non-crop habitat, as long as the height and structure of the vegetation allows proper placement of the enclosure25.
Our blower-vac suction sampling method is non-destructive. Almost all arthropods collected in the sampling net survived, including those soft bodies such as mosquitos and damselflies. The application of this method, however, has some limitations and drawbacks. The blower-vac needs to be operated by two persons. Carrying the blower-vac in the field will result in some disturbance, and therefore this method may underestimate disturbance-sensitive species such as grasshoppers. Fast and abrupt placement of the enclosure in a relatively undisturbed area in the forward direction of movement may limit this potential bias. The loud noise of the blower-vac machine may also cause disturbance, and sampling at night in residential areas is not recommended. The method is not suitable for sampling highly mobile flying insects, such as predatory Odonata or larger hymenopterous parasitoids. As with any sampling method, the combination of the blower-vac with other methods, such as sweep net sampling or destructive harvesting of plants, can provide a more complete and balanced assessment of the arthropod community26.

Repeated assessment of the abundance and diversity of phytophagous and entomophagous arthropods in crops is needed for ecological studies of population dynamics and species interactions, including the study of biological control. Rice is a major staple food, with a high potential for biocontrol by entomophagous arthropods1,2, but which can be disrupted by insecticides3. The diversity of arthropods in rice crops can be high, and arthropod species occupy various crop strata (e.g., ground, stem, canopy, flowers), differ in mode of movement (e.g., walking, jumping, flying) and foraging strategy (e.g., sessile sucking insects, hunting predators and flower visiting pollinators)4.
There is a wide range of arthropod sampling techniques, each with strengths and weaknesses. For instance, pitfall traps can be used to sample ground-dwelling arthropods, but provide activity-dependent relative population estimates5,6. Sweep nets can be used to sample fast-flying insects in the canopy7-9, but give relative estimates of arthropod abundance. The beat sheet method can be used to sample the plant-dwelling arthropod community and provides absolute estimates of arthropod abundance, but it cannot be used effectively in flooded crop fields such as rice paddies10.
Suction sampling, when conducted in combination with an enclosure covering a standardized area of the field, provides absolute estimates of the densities of plant-dwelling arthropods. This method can also be used in flooded rice. Samples can be stored for later processing and identification. The Dietrick vacuum (D-vac)11 is the first commercially developed suction sampler. Although D-vacs are still widely used12-14, they are relatively expensive, have a limited suction force15 and are relatively heavy, which makes them hard to handle in flooded rice fields16. Arida and Heong 16 developed a suction sampler using a petrol-driven leaf blower-vac, and this prototype was further refined by Domingo and Schoenly 17. Advantages of the blower-vac suction sampler as compared to the D-vac are that it is much cheaper and easier to handle.
Although the blower-vac suction sampling method has been used in many ecological studies18-23, the instructions for its modification and application have not been clearly described. Here we present a video-based, detailed description of the modification and application of a petrol-powered leaf blower-vac for suction sampling of arthropod populations in flooded rice fields. The modification is inspired by Arida and Heong 16 and Domingo and Schoenly 17, but the design has been further simplified compared to these original publications, facilitating construction and use.

<table><tbody><tr><td colspan="4">&lt;strong&gt;Machine&lt;/strong&gt;</td></tr><tr><td>Leaf blower-vac</td><td>We used Oleo-Mac BV300, Made in Italy</td><td>Power: 1.0 kW, Displacement: 30.5 cc, Max air volume: 720 m&amp;sup3;/hr, Max air speed: 70 m/sec, Weight: 4.5 kg, Diameter of suction mouth: 113&amp;nbsp;mm</td><td>There are many different brands and models available. For comparable performance, the specifications concerning power and air speed should be similar to those presented here.</td></tr><tr><td colspan="4">&lt;strong&gt;Additional parts for modification&lt;/strong&gt;</td></tr><tr><td>PVC pipe 1</td><td></td><td>Outer &amp;oslash; of end connected to the machine: 112 mm, Inner &amp;oslash; of end connected to PVC pipe 2: 110 mm</td><td>This is the cover of a &amp;oslash; 110 mm PVC pipe</td></tr><tr><td>PVC pipe 2</td><td></td><td>Outer &amp;oslash;: 110 mm, Length: 10 cm</td><td>Normal outer &amp;oslash; 110 mm PVC pipe; to connect PVC pipe 1 and 3</td></tr><tr><td>PVC pipe 3</td><td></td><td>Inner &amp;oslash; of big end: 110 mm, Inner &amp;oslash; of small end: 50 mm</td><td>PVC &amp;oslash; 110 mm to &amp;oslash; 50&amp;nbsp;mm downpipe reducer</td></tr><tr><td>PVC pipe 4</td><td></td><td>Outer &amp;oslash;: 50 mm, Length: 5&amp;nbsp;cm</td><td>Normal &amp;oslash; 50 mm PVC pipe; to connect PVC pipe 3 and 5</td></tr><tr><td>PVC pipe 5</td><td></td><td>Inner &amp;oslash;: 50 mm and 32&amp;nbsp;mm, Outer &amp;oslash; of small part: 38 mm</td><td>PVC &amp;oslash; 50 mm to &amp;oslash; 32 mm downpipe reducer</td></tr><tr><td>Hose</td><td></td><td>Outer &amp;oslash;: 40 mm</td><td>Wire-fortified, flexible plastic hose&amp;nbsp;</td></tr><tr><td>Metal gauze</td><td></td><td>Mesh &amp;oslash;: 1 mm, &amp;oslash;: 60 mm</td><td>Prevent the sampling net from being sucked into the machine</td></tr><tr><td>PVC pipe 6</td><td></td><td>Outer &amp;oslash; of small end: 38&amp;nbsp;mm, Inner &amp;oslash; of big end: 63&amp;nbsp;mm</td><td>PVC &amp;oslash; 32 mm to &amp;oslash; 63 mm reducer</td></tr><tr><td>PVC pipe 7</td><td></td><td>Outer &amp;oslash;: 63 mm, Length: 25 cm</td><td>Normal outer &amp;oslash; 63&amp;nbsp;mm PVC pipe</td></tr><tr><td>U-PVC glue</td><td></td><td></td><td>U-PVC glue; to connect PVC parts</td></tr><tr><td>Metal clamp hoops (2)</td><td>Flexible between &amp;oslash; 35 mm - 51 mm</td><td>To connect the hose with the PVC pipes</td><td></td></tr><tr><td>Thread seal tape</td><td>Width: 18mm</td><td>Seal the hose-PVC connections</td><td></td></tr><tr><td>Screws (3)</td><td></td><td>Length: 25&amp;nbsp;mm</td><td>To connect PVC pipe 1 with the suction mouth of the machine</td></tr><tr><td colspan="4">&lt;strong&gt;Sampling net and enclosure&lt;/strong&gt;</td></tr><tr><td>Sampling net</td><td>Mesh size &amp;oslash;: 0.3 mm, Width of the mouth: 10&amp;nbsp;cm, Height: 30 cm</td><td>The sampling net has a conical shape.</td><td></td></tr><tr><td>Bucket</td><td></td><td>Bottom &amp;oslash;: 40 cm, Volume: 50 L</td><td>Cut the bottom</td></tr><tr><td>Nylon sleeve</td><td></td><td>Mesh size &amp;oslash;: 0.3 mm, Length: 1 m</td><td>To cover the bucket as enclosure</td></tr></tbody></table>

modification and application of a leaf blower-vac for field sampling of arthropods

Rice fields host a large diversity of arthropods, but investigating their population dynamics and interactions is challenging. Here we describe the modification and application of a leaf blower-vac for suction sampling of arthropod populations in rice. When used in combination with an enclosure, application of this sampling device provides absolute estimates of the populations of arthropods as numbers per standardized sampling area. The sampling efficiency depends critically on the sampling duration. In a mature rice crop, a two-minute sampling in an enclosure of 0.13 m2 yields more than 90% of the arthropod population. The device also allows sampling of arthropods dwelling on the water surface or the soil in rice paddies, but it is not suitable for sampling fast flying insects, such as predatory Odonata or larger hymenopterous parasitoids. The modified blower-vac is simple to construct, and cheaper and easier to handle than traditional suction sampling devices, such as D-vac. The low cost makes the modified blower-vac also accessible to researchers in developing countries.

A total of 295 arthropods were collected in 8 three-minute blower-vac samples from a rice crop in the ripening stage in Jiangxi Province, China, in September 2015. To determine the relationship between relative yield (proportion of the arthropods collected in the sample) and sampling duration, each sample was divided into six sub-samples of 30 seconds each. The mean number of individuals per sample was 36.9 &#177; 4.1 (mean &#177; SEM). A total of eight arthropod orders were found, with Hemiptera (28.8%), Araneae (27.5%) and Diptera (17.6%) being dominant (Figure 1). The relative yield, expressed as a percentage of the number of collected arthropods after three minutes, was 52.9% &#177; 5.1, 92.4% &#177; 1.9 and 97.3% &#177; 0.9 after 30 seconds, 2 and 2.5 minutes, respectively (Figure 2).
<img alt="Figure 1" src="/files/ftp_upload/54655/54655fig1.jpg" /> 
Figure 1. Species composition (at the order level) of arthropod samples in the suburbs of Nanchang city in Jiangxi Province, China. Eight samples were taken with a blower-vac of three-minutes each. Error bars represent the standard error of the mean. <a href="https://www.jove.com/files/ftp_upload/54655/54655fig1large.jpg" target="_blank">Please click here to view a larger version of this figure.</a>
<img alt="Figure 2" src="/files/ftp_upload/54655/54655fig2.jpg" /> 
Figure 2. Cumulative relative yield as a function of total sampling duration based on sub-samples of 30 seconds each. The total number of arthropods collected over a sampling duration of three minutes is set at 100%. No arthropods were found upon visual inspection after the last blower-vac sample. Error bars represent standard errors of the mean of eight three-minute samples. <a href="https://www.jove.com/files/ftp_upload/54655/54655fig2large.jpg" target="_blank">Please click here to view a larger version of this figure.</a>

Watch this Scientific Journal Video about Modification and Application of a Leaf Blower-vac for Field Sampling of Arthropods at JoVE.com

Modification and Application of a Leaf Blower-vac for Field Sampling of Arthropods

Assessment of arthropod abundance in crops is critical for investigating population dynamics and species interactions. Here we describe the modification and application of a leaf blower-vac for suction sampling of arthropods in rice.

Rice fields host a large diversity of arthropods, but investigating their population dynamics and interactions is challenging. Here we describe the ...

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Research

JoVE Journal

Environment

8.7K Views.  Wageningen University.  Beoordeling van de geleedpotige overvloed in gewassen is van cruciaal belang voor het onderzoek naar de populatiedynamiek en de soorten interacties. Hier beschrijven we de modificatie en toepassing van een bladblazer-vac voor afzuiging bemonstering van geleedpotigen in rijst. 

Video: Modification and Application of a Leaf Blower-vac for Field Sampling of Arthropods

Technique for Studying Arthropod and Microbial Communities within Tree Tissues

Phloem tissues of pine are habitats for many thousands of organisms. Arthropods and microbes use phloem and cambium tissues to seek mates, lay eggs, rear young, feed, or hide from natural enemies or harsh environmental conditions outside of the tree. Organisms that persist within the phloem habitat are difficult to observe given their location under bark. We provide a technique to preserve intact phloem and prepare it for experimentation with invertebrates and microorganisms. The apparatus is called a &#8216;phloem sandwich&#8217; and allows for the introduction and observation of arthropods, microbes, and other organisms. This technique has resulted in a better understanding of the feeding behaviors, life-history traits, reproduction, development, and interactions of organisms within tree phloem. The strengths of this technique include the use of inexpensive materials, variability in sandwich size, flexibility to re-open the sandwich or introduce multiple organisms through drilled holes, and the preservation and maintenance of phloem integrity. The phloem sandwich is an excellent educational tool for scientific discovery in both K-12 science courses and university research laboratories.

We provide a technique to preserve intact tree phloem and prepare it for observation. We create an apparatus called a phloem sandwich that allows for the introduction and observation of arthropods, microbes, and other organisms that inhabit phloem tissues.

Phloem tissues of pine are habitats for many thousands of organisms.  Arthropods and microbes use phloem and cambium tissues to seek mates, lay eggs, rear ...

Application of Two-spotted Spider Mite Tetranychus urticae for Plant-pest Interaction Studies

The two-spotted spider mite, Tetranychus urticae, is a ubiquitous polyphagous arthropod herbivore that feeds on a remarkably broad array of species, with more than 150 of economic value. It is a major pest of greenhouse crops, especially in Solanaceae and Cucurbitaceae (e.g., tomatoes, eggplants, peppers, cucumbers, zucchini) and greenhouse ornamentals (e.g., roses, chrysanthemum, carnations), annual field crops (such as maize, cotton, soybean, and sugar beet), and in perennial cultures (alfalfa, strawberries, grapes, citruses, and plums)1,2. In addition to the extreme polyphagy that makes it an important agricultural pest, T. urticae has a tendency to develop resistance to a wide array of insecticides and acaricides that are used for its control3-7.
T. urticae is an excellent experimental organism, as it has a rapid life cycle (7 days at 27 &#176;C) and can be easily maintained at high density in the laboratory. Methods to assay gene expression (including in situ hybridization and antibody staining) and to inactivate expression of spider mite endogenous genes using RNA interference have been developed8-10. Recently, the whole genome sequence of T. urticae has been reported, creating an opportunity to develop this pest herbivore as a model organism with equivalent genomic resources that already exist in some of its host plants (Arabidopsis thaliana and the&#160;tomato Solanum lycopersicum)11. Together, these&#160;model organisms could provide insights into molecular bases of plant-pest interactions.
Here, an efficient method for quick and easy collection of a large number of adult female mites, their application on an experimental plant host, and the assessment of the plant damage due to spider mite feeding are described. The presented protocol enables fast and efficient collection of hundreds of individuals at any developmental stage (eggs, larvae, nymphs, adult males, and females) that can be used for subsequent experimental application.

Application of Two-spotted Spider Mite Tetranychus urticae for Plant-pest Interaction Studies

Protocols for efficient preparation of homogenous samples of spider mites, infestation of experimental plants, and assessment of plant damage, as required for studies of plant-pest interaction were developed.

The two-spotted spider mite, Tetranychus urticae, is a ubiquitous polyphagous arthropod herbivore that feeds on a remarkably broad array of species, with ...

Integrated Field Lysimetry and Porewater Sampling for Evaluation of Chemical Mobility in Soils and Established Vegetation

Potentially toxic chemicals are routinely applied to land to meet growing demands on waste management and food production, but the fate of these chemicals is often not well understood. Here we demonstrate an integrated field lysimetry and porewater sampling method for evaluating the mobility of chemicals applied to soils and established vegetation. Lysimeters, open columns made of metal or plastic, are driven into bareground or vegetated soils. Porewater samplers, which are commercially available and use vacuum to collect percolating soil water, are installed at predetermined depths within the lysimeters. At prearranged times following chemical application to experimental plots, porewater is collected, and lysimeters, containing soil and vegetation, are exhumed. By analyzing chemical concentrations in the lysimeter soil, vegetation, and porewater, downward leaching rates, soil retention capacities, and plant uptake for the chemical of interest may be quantified. Because field lysimetry and porewater sampling are conducted under natural environmental conditions and with minimal soil disturbance, derived results project real-case scenarios and provide valuable information for chemical management. As chemicals are increasingly applied to land worldwide, the described techniques may be utilized to determine whether applied chemicals pose adverse effects to human health or the environment.

Field lysimetry and porewater sampling allow researchers to evaluate the fate of chemicals applied to soils and established vegetation. The goal of this protocol is to demonstrate how to install required instrumentation and collect samples for chemical analysis during integrated field lysimetry and porewater sampling experiments.

Potentially toxic chemicals are routinely applied to land to meet growing demands on waste management and food production, but the fate of these chemicals ...

VacuSIP, an Improved InEx Method for In Situ Measurement of Particulate and Dissolved Compounds Processed by Active Suspension Feeders

Benthic suspension feeders play essential roles in the functioning of marine ecosystems. By filtering large volumes of water, removing plankton and detritus, and excreting particulate and dissolved compounds, they serve as important agents for benthic-pelagic coupling. Accurately measuring the compounds removed and excreted by suspension feeders (such as sponges, ascidians, polychaetes, bivalves) is crucial for the study of their physiology, metabolism, and feeding ecology, and is fundamental to determine the ecological relevance of the nutrient fluxes mediated by these organisms. However, the assessment of the rate by which suspension feeders process particulate and dissolved compounds in nature is restricted by the limitations of the currently available methodologies. Our goal was to develop a simple, reliable, and non-intrusive method that would allow clean and controlled water sampling from a specific point, such as the excurrent aperture of benthic suspension feeders, in situ. Our method allows simultaneous sampling of inhaled and exhaled water of the studied organism by using minute tubes installed on a custom-built manipulator device and carefully positioned inside the exhalant orifice of the sampled organism. Piercing a septum on the collecting vessel with a syringe needle attached to the distal end of each tube allows the external pressure to slowly force the sampled water into the vessel through the sampling tube. The slow and controlled sampling rate allows integrating the inherent patchiness in the water while ensuring contamination free sampling. We provide recommendations for the most suitable filtering devices, collection vessel, and storing procedures for the analyses of different particulate and dissolved compounds. The VacuSIP system offers a reliable method for the quantification of undisturbed suspension feeder metabolism in natural conditions that is cheap and easy to learn and apply to assess the physiology and functional role of filter feeders in different ecosystems.

VacuSIP, an Improved InEx Method for In Situ Measurement of Particulate and Dissolved Compounds Processed by Active Suspension Feeders

We introduce the VacuSIP, a simple, non-intrusive, and reliable method for clean and accurate point sampling of water. The system was developed and evaluated for the simultaneous collection of the water inhaled and exhaled by benthic suspension feeders in situ, to cleanly measure removal and excretion of particulate and dissolved compounds.

Benthic suspension feeders play essential roles in the functioning of marine ecosystems. By filtering large volumes of water, removing plankton and ...

Collection and Extraction of Occupational Air Samples for Analysis of Fungal DNA

Traditional methods of identifying fungal exposures in occupational environments, such as culture and microscopy-based approaches, have several limitations that have resulted in the exclusion of many species. Advances in the field over the last two decades have led occupational health researchers to turn to molecular-based approaches for identifying fungal hazards. These methods have resulted in the detection of many species within indoor and occupational environments that have not been detected using traditional methods. This protocol details an approach for determining fungal diversity within air samples through genomic DNA extraction, amplification, sequencing, and taxonomic identification of fungal internal transcribed spacer (ITS) regions. ITS sequencing results in the detection of many fungal species that are either not detected or difficult to identify to species level using culture or microscopy. While these methods do not provide quantitative measures of fungal burden, they offer a new approach to hazard identification and can be used to determine overall species richness and diversity within an occupational environment.

Determining the fungal diversity within an environment is a method utilized in occupational health studies to identify health hazards. This protocol describes DNA extraction from occupational air samples for amplification and sequencing of fungal ITS regions. This approach detects many fungal species that can be overlooked by traditional assessment methods.

Traditional methods of identifying fungal exposures in occupational environments, such as culture and microscopy-based approaches, have several ...

Composition and Distribution Analysis of Bioaerosols Under Different Environmental Conditions

Variable microorganisms in particulate matter (PM) under different environmental conditions may have significant impacts on human health. In this study, we described a protocol for multiple analyses of the biological compositions in environmental PM. Five experiments are presented: (1) PM number monitoring by using a laser particle counter; (2) PM collection by using a cyclonic aerosol sampler; (3) PM collection by using a high-volume air sampler with filters; (4) culturable microbes collection by the Andersen six-stage sampler; and (5) detection of biological composition of environmental PM by bacterial 16SrDNA and fungal ITS region sequencing. We selected hazy days and a livestock farm as two typical examples of the application in this protocol. In this study, these two sampling methods, cyclonic aerosol sampler and filter sampler, showed different sampling efficiency. The cyclonic aerosol sampler performed much better in terms of collecting bacteria, while these two methods showed the same efficiency in collecting fungi. Filter samplers can work under low temperature conditions while cyclonic aerosol samplers have a sampling limitation for temperature. A solid impacting sampler, such as an Andersen six-stage sampler, can be used to sample bioaerosols directly into the culture medium, which increases the survival rate of culturable microorganisms. However, this method mainly relies on culture while more than 99% of microbes cannot be cultured. DNA extracted from the culturable bacteria collected by the Andersen six-stage sampler and samples collected by cyclonic aerosol sampler and filter sampler were detected by bacterial 16S rDNA and fungal ITS region sequencing.All the methods above may have wide application in many fields of study, such as environmental monitoring and airborne pathogen detection. From these results, we can conclude that these methods can be used under different conditions and may help other researchers further explore the health impacts of environmental bioaerosols.

Understanding the biological composition of environmental particulate matter is important for the study of its significant impacts on human health and disease spread. Here, we used three types of bioaerosol sampling methods and a biological analysis of airborne microbes to better explore airborne microbial communities under different environmental conditions.

Variable microorganisms in particulate matter (PM) under different environmental conditions may have significant impacts on human health. In this study, ...

A Method for Quantifying Foliage-Dwelling Arthropods

Terrestrial arthropods play an important role in our environment. Quantifying arthropods in a way that allows for a precise index or estimates of density requires a method with high detection probability and a known sampling area. While most described methods provide a qualitative or semi-quantitative estimate adequate for describing species presence, richness, and diversity, few provide an adequately consistent detection probability and known or consistent sampling areas to provide an index or estimate with adequate precision to detect differences in abundance across environmental, spatial, or temporal variables. We describe how to quantify leaf-dwelling arthropods by sealing the leaves and end of branches in a bag, clipping and freezing the bagged material, and rinsing the previously frozen material in water to separate arthropods from the substrate and quantify them. As we demonstrate, this method can be used at a landscape scale to quantify leaf-dwelling arthropods with adequate precision to test for and describe how spatial, temporal, environmental, and ecological variables influence arthropod richness and abundance. This method allowed us to detect differences in density, richness, and diversity of leaf-dwelling arthropods among 5 genera of trees commonly found in southeastern deciduous forests.

We describe how to quantify leaf dwelling arthropods by sealing the leaves and end of branches in a bag, clipping and freezing the bagged material, and rinsing the previously frozen material in water to separate arthropods from the substrate for quantification.

Terrestrial arthropods play an important role in our environment. Quantifying arthropods in a way that allows for a precise index or estimates of density ...

Quantifying Corticolous Arthropods Using Sticky Traps

Terrestrial arthropods play an important role in our environment. Quantifying arthropods in a way that allows for a precise index or estimate of density requires a method with high detection probability and a consistent sampling area. We used manufactured sticky traps to compare abundance, total length (a surrogate for biomass), richness, and Shannon diversity of corticolous arthropods among the boles of 5 tree species. Efficacy of this method was adequate to detect variation in corticolous arthropods among tree species and provide a standard error of the mean that was &#60;20% of the mean for all estimates with sample sizes from 7 to 15 individual trees of each species. Our results indicate, even with these moderate sample sizes, the level of precision of arthropod community metrics produced with this approach is adequate to address most ecological questions regarding temporal and spatial variation in corticolous arthropods. Results from this method differ from other quantitative approaches such as chemical knockdown, visual inspection, and funnel traps in that they provide an indication of corticolous arthropod activity over a relatively long-term, better including temporary bole residents, flying arthropods that temporarily land on the tree bole and crawling arthropods that use the tree bole as a travel route from the ground to higher forest foliage. Furthermore, we believe that commercially manufactured sticky traps provide more precise estimates and are logistically simpler than the previously described method of directly applying a sticky material to tree bark or applying a sticky material to tape or other type of backing and applying that to the tree bark.

We describe a semi-quantitative approach of measuring characteristics of corticolous (bark-dwelling) arthropod communities. We placed commercially manufactured sticky traps on tree boles to estimate abundance, total length (a surrogate to biomass), richness, and Shannon diversity for comparison among tree species.

Terrestrial arthropods play an important role in our environment. Quantifying arthropods in a way that allows for a precise index or estimate of density ...

Low-Cost Automated Flight Intercept Trap for the Temporal Sub-Sampling of Flying Insects Attracted to Artificial Light at Night

Sampling methods are selected depending on the targeted species or the spatial and temporal requirements of the study. However, most methods for passive sampling of flying insects have a poor temporal resolution because it is time-consuming, costly and/or logistically difficult to perform. Effective sampling of flying insects attracted to artificial light at night (ALAN) requires sampling at user-defined time points (nighttime only) across well-replicated sites resulting in major time and labor-intensive survey effort or expensive automated technologies. Described here is a low-cost automated intercept trap that requires no specialist equipment or skills to construct and operate, making it a viable option for studies that require temporal sub-sampling across multiple sites. The trap can be used to address a wide range of other ecological questions that require a greater temporal and spatial scale than is feasible with previous trap technology.

To study the impacts of artificial light at night (ALAN) on nocturnal flying insects, sampling needs to be confined to nighttime. The protocol describes a low-cost automated flight intercept trap that allows researchers to sample at user-defined periods with increased replication.

Sampling methods are selected depending on the targeted species or the spatial and temporal requirements of the study. However, most methods for passive ...

Electroantennographic Bioassay as a Screening Tool for Host Plant Volatiles

Plant volatiles play an important role in plant-insect interactions. Herbivorous insects use plant volatiles, known as kairomones, to locate their host plant.1,2 When a host plant is an important agronomic commodity feeding damage by insect pests can inflict serious economic losses to growers. Accordingly, kairomones can be used as attractants to lure or confuse these insects and, thus, offer an environmentally friendly alternative to pesticides for insect control.3 Unfortunately, plants can emit a vast number volatiles with varying compositions and ratios of emissions dependent upon the phenology of the commodity or the time of day. This makes identification of biologically active components or blends of volatile components an arduous process. To help identify the bioactive components of host plant volatile emissions we employ the laboratory-based screening bioassay electroantennography (EAG). EAG is an effective tool to evaluate and record electrophysiologically the olfactory responses of an insect via their antennal receptors. The EAG screening process can help reduce the number of volatiles tested to identify promising bioactive components. However, EAG bioassays only provide information about activation of receptors. It does not provide information about the type of insect behavior the compound elicits; which could be as an attractant, repellent or other type of behavioral response. Volatiles eliciting a significant response by EAG, relative to an appropriate positive control, are typically taken on to further testing of behavioral responses of the insect pest. The experimental design presented will detail the methodology employed to screen almond-based host plant volatiles4,5 by measurement of the electrophysiological antennal responses of an adult insect pest navel orangeworm (Amyelois transitella) to single components and simple blends of components via EAG bioassay. The method utilizes two excised antennae placed across a "fork" electrode holder. The protocol demonstrated here presents a rapid, high-throughput standardized method for screening volatiles. Each volatile is at a set, constant amount as to standardize the stimulus level and thus allow antennal responses to be indicative of the relative chemoreceptivity. The negative control helps eliminate the electrophysiological response to both residual solvent and mechanical force of the puff. The positive control (in this instance acetophenone) is a single compound that has elicited a consistent response from male and female navel orangeworm (NOW) moth. An additional semiochemical standard that provides consistent response and is used for bioassay studies with the male NOW moth is (Z,Z)-11,13-hexdecadienal, an aldehyde component from the female-produced sex pheromone.6-8

A method to rapidly screen host plant volatiles by measurement of the electrophysiological response of adult navel orangeworm (Amyelois transitella) antennae to single components and blends via electroantennographic analysis is demonstrated.

Plant volatiles play an important role in plant-insect interactions. Herbivorous insects use plant volatiles, known as kairomones, to locate their host ...

Modification and Application of a Leaf Blower-vac for Field Sampling of Arthropods

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