Name: application of two-spotted spider mite tetranychus urticae for plant-pest interaction studies
Uploaded: 2014-07-04T13:00:00
Description: Watch this Scientific Journal Video about Application of Two-spotted Spider Mite Tetranychus urticae for Plant-pest Interaction Studies at JoVE.com

This project was funded by the Government of Canada through Genome Canada and the Ontario Genomics Institute (OGI-046), and Ontario Research Fund&#8211;Global Leadership in Genomics and Life Sciences GL2-01-035 (to M.G. and V.G.). T.V.L. is a postdoctoral fellow of the Fund for Scientific Research Flanders (FWO).

1. Maintenance of the Spider Mite Population
NOTE: Spider mites are reared on California red kidney beans (Phaseolus vulgaris).
<ol>
	<li>Grow bean plants from seeds for 2-3 weeks prior to infestation.</li>
	<li>Intermix these plants with infested plants; adult mites will rapidly colonize fresh plant material.</li>
	<li>Remove old infested bean plants every 7-10 days,&#160;replacing them with fresh plants.</li>
</ol>
2. Collecting Adult Female Mites
<ol>
	<...

<ol>
	<li>Jeppson, L. R., Keifer, H. H., Baker, E. W. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=.">.</a> Mites injurious to economic plants. , (1975).</li><li>Migeon, A., Dorkeld, F. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Spider+Mites+Web:+a+comprehensive+database+for+the+Tetranychidae.">Spider Mites Web: a comprehensive database for the Tetranychidae.</a> http://www.montpellier.inra.fr/CBGP/spmweb. , (2013).</li><li>Croft, B. A., Vandebaan, H. E. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Ecological+and+Genetic-Factors+Influencing+Evolution+of+Pesticide+Resistance+in+Tetranychid+and+Phytoseiid+Mites.">Ecological and Genetic-Factors Influencing Evolution of Pesticide Resistance in Tetranychid and Phytoseiid Mites.</a> Exp Appl Acarol. 4, 277-300 (1988).</li><li>Van Leeuwen, T., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Mitochondrial+heteroplasmy+and+the+evolution+of+insecticide+resistance:+Non-Mendelian+inheritance+in+action.">Mitochondrial heteroplasmy and the evolution of insecticide resistance: Non-Mendelian inheritance in action.</a> Proceedings of the National Academy of Sciences of the United States of America. 105, 5980-5985 (2008).</li><li>Van Leeuwen, T., Vontas, J., Tsagkarakou, A., Dermauw, W., Tirry, L. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Acaricide+resistance+mechanisms+in+the+two-spotted+spider+mite+Tetranychus+urticae+and+other+important+Acari:+A+review.">Acaricide resistance mechanisms in the two-spotted spider mite Tetranychus urticae and other important Acari: A review.</a> Insect Biochem Molec. 40, 563-572 (2010).</li><li>Dermauw, W., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+cys-loop+ligand-gated+ion+channel+gene+family+of+Tetranychus+urticae:+Implications+for+acaricide+toxicology+and+a+novel+mutation+associated+with+abamectin+resistance.">The cys-loop ligand-gated ion channel gene family of Tetranychus urticae: Implications for acaricide toxicology and a novel mutation associated with abamectin resistance.</a> Insect Biochem Molec. 42, 455-465 (2012).</li><li>Van Leeuwen, T., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Population+bulk+segregant+mapping+uncovers+resistance+mutations+and+the+mode+of+action+of+a+chitin+synthesis+inhibitor+in+arthropods.">Population bulk segregant mapping uncovers resistance mutations and the mode of action of a chitin synthesis inhibitor in arthropods.</a> Proceedings of the National Academy of Sciences. 109, 4407-4412 (2012).</li><li>Dearden, P. K., Donly, C., Grbic, M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Expression+of+pair-rule+gene+homologues+in+a+chelicerate:+early+patterning+of+the+two-spotted+spider+mite+Tetranychus+urticae.">Expression of pair-rule gene homologues in a chelicerate: early patterning of the two-spotted spider mite Tetranychus urticae.</a> Development. 129, 5461-5472 (2002).</li><li>Khila, A., Grbic, M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Gene+silencing+in+the+spider+mite+Tetranychus+urticae:+dsRNA+and+siRNA+parental+silencing+of+the+Distal-less+gene.">Gene silencing in the spider mite Tetranychus urticae: dsRNA and siRNA parental silencing of the Distal-less gene.</a> Development genes and evolution. 217, 241-251 (2007).</li><li>Grbic, M., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Mity+model:+Tetranychus+urticae,+a+candidate+for+chelicerate+model+organism.">Mity model: Tetranychus urticae, a candidate for chelicerate model organism.</a> BioEssays : news and reviews in molecular, cellular and developmental biology. 29, 489-496 (2007).</li><li>Grbic, M., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+genome+of+Tetranychus+urticae+reveals+herbivorous+pest+adaptations.">The genome of Tetranychus urticae reveals herbivorous pest adaptations.</a> Nature. 479, 487-492 (2011).</li><li>Kliebenstein, D., Pedersen, D., Barker, B., Mitchell-Olds, T. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Comparative+analysis+of+quantitative+trait+loci+controlling+glucosinolates,+myrosinase+and+insect+resistance+in+Arabidopsis+thaliana.">Comparative analysis of quantitative trait loci controlling glucosinolates, myrosinase and insect resistance in Arabidopsis thaliana.</a> Genetics. 161, 325-332 (2002).</li><li>Abe, H., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Function+of+jasmonate+in+response+and+tolerance+of+Arabidopsis+to+thrip+feeding.">Function of jasmonate in response and tolerance of Arabidopsis to thrip feeding.</a> Plant &amp; cell physiology. 49, 68-80 (2008).</li><li>Whiteman, N. K., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Mining+the+plant-herbivore+interface+with+a+leafmining+Drosophila+of+Arabidopsis.">Mining the plant-herbivore interface with a leafmining Drosophila of Arabidopsis.</a> Molecular ecology. 20, 995-1014 (2011).</li><li>Goodspeed, D., Chehab, E. W., Min-Venditti, A., Braam, J., Covington, M. F. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Arabidopsis+synchronizes+jasmonate-mediated+defense+with+insect+circadian+behavior.">Arabidopsis synchronizes jasmonate-mediated defense with insect circadian behavior.</a> Proc Natl Acad Sci U S A. 109, 4674-4677 (2012).</li><li>Kim, J. H., Lee, B. W., Schroeder, F. C., Jander, G. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Identification+of+indole+glucosinolate+breakdown+products+with+antifeedant+effects+on+Myzus+persicae+(green+peach+aphid).">Identification of indole glucosinolate breakdown products with antifeedant effects on Myzus persicae (green peach aphid).</a> The Plant journal : for cell and molecular biology. 54, 1015-1026 (2008).</li><li>Adio, A. M., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Biosynthesis+and+defensive+function+of+Ndelta-acetylornithine,+a+jasmonate-induced+Arabidopsis+metabolite.">Biosynthesis and defensive function of Ndelta-acetylornithine, a jasmonate-induced Arabidopsis metabolite.</a> Plant Cell. 23, 3303-3318 (2011).</li><li>Li, L., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+tomato+homolog+of+CORONATINE-INSENSITIVE1+is+required+for+the+maternal+control+of+seed+maturation,+jasmonate-signaled+defense+responses,+and+glandular+trichome+development.">The tomato homolog of CORONATINE-INSENSITIVE1 is required for the maternal control of seed maturation, jasmonate-signaled defense responses, and glandular trichome development.</a> Plant Cell. 16, 126-143 (2004).</li><li>Kant, M. R., Ament, K., Sabelis, M. W., Haring, M. A., Schuurink, R. C. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Differential+timing+of+spider+mite-induced+direct+and+indirect+defenses+in+tomato+plants.">Differential timing of spider mite-induced direct and indirect defenses in tomato plants.</a> Plant Physiol. 135, 483-495 (2004).</li><li>Schneider, C. A., Rasband, W. S., Eliceiri, K. W. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=NIH+Image+to+ImageJ:+25+years+of+image+analysis.">NIH Image to ImageJ: 25 years of image analysis.</a> Nat Methods. 9, 671-675 (2012).</li></ol>

This video demonstrates protocols used to isolate and to infest plants with large numbers of adult female mites. Although we presented this protocol using A. thaliana, it can be used for any plant-spider mite interaction system and is currently being successfully applied also on tomato and grapevine (Vitis vinifera) plants. The protocol yields reproducible results, indicating that collected mites are of comparable physiological state (Figure&#160;3).
While th...

Plant-pest interaction is a topic of great scientific and economic importance. It was historically studied using both crop plants (such as tomato) and the model plant, A. thaliana. In both cases, susceptibility of plant to herbivore could be measured either directly through assessment of plant phenotype after herbivore attack or indirectly through the assessment of pest performance.
Direct measurements of plant susceptibility were utilized previously for a number of insect pest species using a range of methods. For example, herbivory of lepidopteran larvae is measured as an estimation of the portion of plant tissue consumed by either Plutella xylostella (diamondback moth)&#160;or Trichoplusia ni (cabbage looper)&#160;by the naked eye with the help of a grid12. Also, there are methods that utilize digital imaging of leaf damage with subsequent quantitative image analysis. Such methods were used in studies of A. thaliana interaction with Frankliniella occidentalis (western flower thrips)13, Scaptomyza flava (leaf-mining drosophila)14, and T. ni15.
Indirect measurements of plant susceptibility are widely used in studies of plant-pest interaction. For example, susceptibility of A. thaliana to peach aphid Myzus persicae herbivory is typically assessed through analysis of pest fecundity and description of the gross morphology of a plant after interaction16,17. Another typical indirect indicator of A. thaliana susceptibility to a pest is a dry or wet weight assessment of the herbivore. This parameter is commonly used to characterize herbivory of lepidoterans, such as Pieris rapae (small white), P. xylostella, or T. ni at their larval or pupal stages15,17.
Spider mites are cell-content feeders. Mite-induced damage is recognized as a collection of chlorotic spots that range in color from white to pale green. The susceptibility of a plant host to spider mite herbivory was previously assessed either indirectly through the analysis of spider mite performance days post-infestation18,19, or directly using gross morphology of plants weeks post-infestation18 or using a digital imaging of leaves exposed to mites for days with subsequent automated image analysis19. These methods were being developed and used for studies of interactions between tomato plants and T. urticae, and&#160;typically used small numbers of spider mites (5-15 per treatment) that were collected from the mixed mite population and were placed on the leaf surface using a soft bristle brush. However, these methods are not suitable for studies where greater numbers of mites need to be applied. In addition, while direct processing of leaf images in image analysis software such as Adobe Photoshop (San Jose, CA) or ImageJ20 can be used for the analysis of tomato damage, these protocols need modification in order to be applied to leaves that have greater reflectivity of surface or are lightly colored and have highly visible trichomes (e.g.,&#160;A. thaliana) that interfere with automated selection of chlorotic spots that mark plant damage. Furthermore, the developmental stage of spider mites that can be readily utilized with the previous methods is limited to the most prevalent and easily identifiable adult females and precludes utilization of other developmental stages.
The first critical step toward high-throughput analysis of plant-spider mite interaction is to establish reproducible, simple and robust protocols to challenge plants with spider mites and reliably assess interaction outcomes.
In this video, 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. In addition, these protocols can be applied to any mite host plant, but are specifically demonstrated in the case of A. thaliana.

<table border="0" cellpadding="0" cellspacing="0" width="1157">
	<tbody>
		<tr height="21">
			<td colspan="4" height="21" style="height:21px;width:231px;">Plant material:</td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;width:231px;">California red kidney bean</td>
			<td style="width:275px;">Stokes, Thorold, ON, Canada</td>
			<td style="width:125px;">NA</td>
			<td style="width:527px;">Two week old, well infested with spider mites two or three days before use. Other cultivars of Phaseolus vulgaris can be used.</td>
		</tr>
		<tr height="21">
			<td colspan="4" height="21" style="height:21px;width:231px;">Chemicals:</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:231px;">Tween 20</td>
			<td>Sigma-Aldrich</td>
			<td style="width:125px;">P9416</td>
			<td style="width:527px;">1% stock solution is prepared to simplify aliquoting</td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;width:231px;">Tap water</td>
			<td>Any supplier</td>
			<td style="width:125px;">NA</td>
			<td style="width:527px;">At room temperature, heat- and cold-shock affect mite survival rate and peformance</td>
		</tr>
		<tr height="21">
			<td colspan="4" height="21" style="height:21px;width:231px;">Other materials and equipment:</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:231px;">Plastic tray</td>
			<td>Any supplier</td>
			<td style="width:125px;">NA</td>
			<td style="width:527px;">-</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:231px;">Set of scissors</td>
			<td>Any supplier</td>
			<td style="width:125px;">NA</td>
			<td style="width:527px;">-</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:231px;">2 L beakers</td>
			<td>Any supplier</td>
			<td style="width:125px;">NA</td>
			<td style="width:527px;">-</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:231px;">Paper towels</td>
			<td>Any supplier</td>
			<td style="width:125px;">NA</td>
			<td style="width:527px;">-</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:231px;">Sets of sieves</td>
			<td style="width:275px;">Manufactured in house</td>
			<td style="width:125px;">NA</td>
			<td style="width:527px;">Detailed instructions are available</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:231px;">Thin brush</td>
			<td>Any supplier</td>
			<td style="width:125px;">NA</td>
			<td style="width:527px;">-</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:231px;">Pipettes</td>
			<td>Any supplier</td>
			<td style="width:125px;">NA</td>
			<td style="width:527px;">-</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:231px;">Pipette tips</td>
			<td>Any supplier</td>
			<td style="width:125px;">NA</td>
			<td style="width:527px;">0.2 and 1 mL</td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;width:231px;">1.5 mL centrifuge tubes</td>
			<td>Any supplier</td>
			<td style="width:125px;">NA</td>
			<td style="width:527px;">-</td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;width:231px;">Air pump</td>
			<td>Any supplier</td>
			<td style="width:125px;">NA</td>
			<td style="width:527px;">Aquarium type pump with inverted air flow. Vacuum line can be used. Required pressure drop is approx. 2-4 psi</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:231px;">Stereoscope</td>
			<td>Any supplier</td>
			<td style="width:125px;">NA</td>
			<td style="width:527px;">-</td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;width:231px;">Scanner</td>
			<td>Epson</td>
			<td style="width:125px;">V30</td>
			<td style="width:527px;">Any flatbed scanner allowing necessary degree of control over scan quality. We use Epson V30 for our experiments.</td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;width:231px;">Computer</td>
			<td>Any supplier</td>
			<td style="width:125px;">NA</td>
			<td style="width:527px;">Windows or OS X PC which is compatible with scanner hardware and Adobe Photoshop software.</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:231px;">Adobe Photoshop software</td>
			<td style="width:275px;">Adobe Systems Inc., San Jose, CA, USA</td>
			<td style="width:125px;">various</td>
			<td style="width:527px;">Any version with Histogram tool included.</td>
		</tr>
	</tbody>
</table>

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.

Using 20 to 30 infested bean plants, one can collect around 2,000 adult female mites using sieves. The time required to infest 10 plants with 20 mites per plant is approximately 15 min&#160;if using a brush to transfer mites. Combinations of collection and application methods are shown in Figure&#160;2.
This protocol generates reproducible results of plant damage, demonstrating that collected mites are of similar physiological state and suitable for plant-spider mite interacti...

Watch this Scientific Journal Video about Application of Two-spotted Spider Mite Tetranychus urticae for Plant-pest Interaction Studies at JoVE.com

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.

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 ...

application-two-spotted-spider-mite-tetranychus-urticae-for-plant

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Environment

Physical, Chemical and Biological Characterization of Six Biochars Produced for the Remediation of Contaminated Sites

The physical and chemical properties of biochar vary based on feedstock sources and production conditions, making it possible to engineer biochars with specific functions (e.g. carbon sequestration, soil quality improvements, or contaminant sorption). In 2013, the International Biochar Initiative (IBI) made publically available their Standardized Product Definition and Product Testing Guidelines (Version 1.1) which set standards for physical and chemical characteristics for biochar. Six biochars made from three different feedstocks and at two temperatures were analyzed for characteristics related to their use as a soil amendment. The protocol describes analyses of the feedstocks and biochars and includes: cation exchange capacity (CEC), specific surface area (SSA), organic carbon (OC) and moisture percentage, pH, particle size distribution, and proximate and ultimate analysis. Also described in the protocol are the analyses of the feedstocks and biochars for contaminants including polycyclic aromatic hydrocarbons (PAHs), polychlorinated biphenyls (PCBs), metals and mercury as well as nutrients (phosphorous, nitrite and nitrate and ammonium as nitrogen). The protocol also includes the biological testing procedures, earthworm avoidance and germination assays. Based on the quality assurance / quality control (QA/QC) results of blanks, duplicates, standards and reference materials, all methods were determined adequate for use with biochar and feedstock materials. All biochars and feedstocks were well within the criterion set by the IBI and there were little differences among biochars, except in the case of the biochar produced from construction waste materials. This biochar (referred to as Old biochar) was determined to have elevated levels of arsenic, chromium, copper, and lead, and failed the earthworm avoidance and germination assays. Based on these results, Old biochar would not be appropriate for use as a soil amendment for carbon sequestration, substrate quality improvements or remediation.

Biochar is a carbon-rich material used as a soil amendment with the ability to sustainably sequester carbon, improve substrate quality and sorb contaminants. This protocol describes the 17 analytical methods used for the characterization of biochar, which is required prior to large scale implementation of these amendments in the environment.

The physical and chemical properties of biochar vary based on feedstock sources and production conditions, making it possible to engineer biochars with ...

Characterization and Application of Passive Samplers for Monitoring of Pesticides in Water

Five different water passive samplers were calibrated under laboratory conditions for measurement of 124 legacy and current used pesticides. This study provides a protocol for the passive sampler preparation, calibration, extraction method and instrumental analysis. Sampling rates (RS) and passive sampler-water partition coefficients (KPW) were calculated for silicone rubber, polar organic chemical integrative sampler POCIS-A, POCIS-B, SDB-RPS and C18 disk. The uptake of the selected compounds depended on their physicochemical properties, i.e., silicone rubber showed a better uptake for more hydrophobic compounds (log octanol-water partition coefficient (KOW) &#62; 5.3), whereas POCIS-A, POCIS-B and SDB-RPS disk were more suitable for hydrophilic compounds (log KOW &#60; 0.70).

A protocol about the characterization and application of five different passive sampling devices is presented.

Five different water passive samplers were calibrated under laboratory conditions for measurement of 124 legacy and current used pesticides. This study ...

Clean Sampling and Analysis of River and Estuarine Waters for Trace Metal Studies

Most of the trace metal concentrations in ambient waters obtained a few decades ago have been considered unreliable owing to the lack of contamination control. Developments of some techniques aiming to reduce trace metal contamination in the last couple of decades have resulted in concentrations reported now being orders of magnitude lower than those in the past. These low concentrations often necessitate preconcentration of water samples prior to instrumental analysis of samples. Since contamination can appear in all phases of trace metal analyses, including sample collection (and during preparation of sampling containers), storage and handling, pretreatments, and instrumental analysis, specific care needs to be taken in order to reduce contamination levels at all steps. The effort to develop and utilize "clean techniques" in trace metal studies allows scientists to investigate trace metal distributions and chemical and biological behavior in greater details. This advancement also provides the required accuracy and precision of trace metal data allowing for environmental conditions to be related to trace metal concentrations in aquatic environments.
This protocol that is presented here details needed materials for sample preparation, sample collection, sample pretreatment including preconcentration, and instrumental analysis. By reducing contamination throughout all phases mentioned above for trace metal analysis, much lower detection limits and thus accuracy can be achieved. The effectiveness of "clean techniques" is further demonstrated using low field blanks and good recoveries for standard reference material. The data quality that can be obtained thus enables the assessment of trace metal distributions and their relationships to environmental parameters.

Special care using "clean techniques" is required to properly collect and process water samples for trace metal studies in aquatic environments. A protocol for sampling, processing, and analytical procedures with the aim of obtaining reliable environmental monitoring data and results with high sensitivity for detailed trace metal studies is presented.

Most of the trace metal concentrations in ambient waters obtained a few decades ago have been considered unreliable owing to the lack of contamination ...

Remote Sensing Evaluation of Two-spotted Spider Mite Damage on Greenhouse Cotton

The objective of this study was to evaluate a ground-based multispectral optical sensor as a remote sensing tool to assess foliar damage caused by the two-spotted spider mite (TSSM), Tetranychus urticae Koch, on greenhouse grown cotton. TSSM is a polyphagous pest which occurs on a variety of field and horticultural crops. It often becomes an early season pest of cotton in damaging proportions as opposed to being a late season innocuous pest in the mid-southern United States. Evaluation of acaricides is important for maintaining the efficacy of and preventing resistance to the currently available arsenal of chemicals and newly developed control agents. Enumeration of spider mites for efficacy evaluations is laborious and time consuming. Therefore, subjective visual damage rating is commonly used to assess density of spider mites. The NDVI (Normalized Difference Vegetation Index) is the most widely used statistic to describe the spectral reflectance characteristics of vegetation canopy to assess plant stress and health consequent to spider mite infestations. Results demonstrated that a multispectral optical sensor is an effective tool in distinguishing varying levels of infestation caused by T. urticae on early season cotton. This remote sensing technique may be used in lieu of a visual rating to evaluate insecticide treatments.

This manuscript describes a multispectral optical sensor that effectively detected damage to early season cotton artificially infested with varying densities of the two-spotted spider mite populations.

The objective of this study was to evaluate a ground-based multispectral optical sensor as a remote sensing tool to assess foliar damage caused by the ...

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.

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 ...

Vegetated Treatment Systems for Removing Contaminants Associated with Surface Water Toxicity in Agriculture and Urban Runoff

Urban stormwater and agriculture irrigation runoff contain a complex mixture of contaminants that are often toxic to adjacent receiving waters. Runoff may be treated with simple systems designed to promote sorption of contaminants to vegetation and soils and promote infiltration. Two example systems are described: a bioswale treatment system for urban stormwater treatment, and a vegetated drainage ditch for treating agriculture irrigation runoff. Both have similar attributes that reduce contaminant loading in runoff: vegetation that results in sorption of the contaminants to the soil and plant surfaces, and water infiltration. These systems may also include the integration of granulated activated carbon as a polishing step to remove residual contaminants. Implementation of these systems in agriculture and urban watersheds requires system monitoring to verify treatment efficacy. This includes chemical monitoring for specific contaminants responsible for toxicity. The current paper emphasizes monitoring of current use pesticides since these are responsible for surface water toxicity to aquatic invertebrates.

This article summarizes the design attributes and the effectiveness of treatment systems that treat urban stormwater and agriculture irrigation runoff to remove pesticides and other contaminants associated with aquatic toxicity.

Urban stormwater and agriculture irrigation runoff contain a complex mixture of contaminants that are often toxic to adjacent receiving waters. Runoff may ...

The Plant Infection Test: Spray and Wound-Mediated Inoculation with the Plant Pathogen Magnaporthe Grisea

Plants possess a powerful system to defend themselves against potential threats by pathogenic fungi. For agriculturally important plants, however, current measures to combat such pathogens have proved too conservative and, thus, not sufficiently effective, and they can potentially pose environmental risks. Therefore, it is extremely necessary to identify host-resistance factors to assist in controlling plant diseases naturally through the identification of resistant germplasm, the isolation and characterization of resistance genes, and the molecular breeding of resistant cultivars. In this regard, there is need to establish an accurate, rapid, and large-scale inoculation method to breed and develop plant resistance genes. The rice blast fungal pathogen Magnaporthe grisea causes severe disease symptoms and yield losses. Recently, M. grisea has emerged as a model organism for studying the mechanisms of plant-fungal pathogen interactions. Hence, we report the development of a plant virulence test method that is specific for M. grisea. This method provides for both spray inoculation with a conidial suspension and wounding inoculation with mycelium cubes or droplets of conidial suspension. The key step of the wounding inoculation method for detached rice leaves is to make wounds on plant leaves, which avoids any interference caused by host penetration resistance. This spray/wounding protocol contributes to the rapid, accurate, and large-scale screening of the pathotypes of M. grisea isolates. This integrated and systematic plant infection method will serve as an excellent starting point for gaining a broad perspective of issues in plant pathology.

The Plant Infection Test: Spray and Wound-Mediated Inoculation with the Plant Pathogen Magnaporthe Grisea

Here, we present a protocol to test plant virulence with the plant pathogen Magnaporthe grisea. This report will contribute to the large-scale screening of the pathotypes of fungi isolates and serve as an excellent starting point for understanding the resistant mechanisms of plants during molecular breeding.

Plants possess a powerful system to defend themselves against potential threats by pathogenic fungi. For agriculturally important plants, however, current ...

Rearing and Long-Term Maintenance of Eristalis tenax Hoverflies for Research Studies

With an estimated 6000 species worldwide, hoverflies are ecologically important as alternative pollinators to domesticated honeybees. However, they are also a useful scientific model to study motion vision and flight dynamics in a controlled laboratory setting. As the larvae develop in organically polluted water, they are useful models for investigating investment in microbial immunity. While large scale commercial breeding for agriculture already occurs, there are no standardized protocols for maintaining captive populations for scientific studies. This is important as commercial captive breeding programs focusing on mass output during peak pollination periods may fail to provide a population that is consistent, stable and robust throughout the year, as is often needed for other research purposes. Therefore, a method to establish, maintain and refresh a captive research population is required. Here, we describe the utilization of an artificial hibernation cycle, in addition to the nutritional and housing requirements, for long term maintenance of Eristalis tenax. Using these methods, we have significantly increased the health and longevity of captive populations of E. tenax compared to previous reports. We furthermore discuss small scale rearing methods and options for optimizing yields and manipulating population demographics.

Rearing and Long-Term Maintenance of Eristalis tenax Hoverflies for Research Studies

The overall goal of these procedures is to establish, maintain and refresh a captive population of Eristalis tenax in a research setting.

With an estimated 6000 species worldwide, hoverflies are ecologically important as alternative pollinators to domesticated honeybees. However, they are ...

Experimental Protocol for Examining Behavioral Response Profiles in Larval Fish: Application to the Neuro-stimulant Caffeine

Fish models and behaviors are increasingly used in the biomedical sciences; however, fish have long been the subject of ecological, physiological and toxicological studies. Using automated digital tracking platforms, recent efforts in neuropharmacology are leveraging larval fish locomotor behaviors to identify potential therapeutic targets for novel small molecules. Similar to these efforts, research in the environmental sciences and comparative pharmacology and toxicology is examining various behaviors of fish models as diagnostic tools in tiered evaluation of contaminants and real-time monitoring of surface waters for contaminant threats. Whereas the zebrafish is a popular larval fish model in the biomedical sciences, the fathead minnow is a common larval fish model in ecotoxicology. Unfortunately, fathead minnow larvae have received considerably less attention in behavioral studies. Here, we develop and demonstrate a behavioral profile protocol using caffeine as a model neurostimulant. Though photomotor responses of fathead minnows were occasionally affected by caffeine, zebrafish&#160;were markedly more sensitive for photomotor and locomotor endpoints, which responded at environmentally relevant levels. Future studies are needed to understand comparative behavioral sensitivity differences among fish with age and time of day, and to determine whether similar behavioral effects would occur in nature and be indicative of adverse outcomes at the individual or population levels of biological organization.

Here, we present a protocol to examine larval zebrafish and fathead minnow locomotor activities and photomotor responses (PMR) using an automated tracking software. When incorporated in common toxicology bioassays, analyses of these behaviors provide a diagnostic tool to examine chemical bioactivity. This protocol is described using caffeine, a model neurostimulant.

Fish models and behaviors are increasingly used in the biomedical sciences; however, fish have long been the subject of ecological, physiological and ...

Generating Homo- and Heterografts Between Watermelon and Bottle Gourd for the Study of Cold-responsive MicroRNAs

MicroRNAs (miRNAs) are endogenous small non-coding RNAs of about 20 - 24 nt, known to play important roles in plant development and adaptation. There is an accumulating evidence showing that the expressions of certain miRNAs are altered when grafting, an agricultural practice commonly used by farmers to improve crop tolerance to biotic and abiotic stresses. Bottle gourd is an inherently climate-resilient crop compared to many other major cucurbits, including watermelon, rendering it one of the most widely used rootstocks for the latter. The recent advancement of high-throughput sequencing technologies has provided great opportunities to investigate cold-responsive miRNAs and their contributions to heterograft advantages; yet, adequate experimental procedures are a prerequisite for this purpose. Here, we present a detailed protocol for efficiently generating homo- and heterografts between the cold-susceptible watermelon and the cold-tolerant bottle gourd, in addition to methods of tissue sampling, data generation, and data analysis. The presented methods are also useful for other plant-grafting systems, to interrogate miRNA regulations under various environmental stresses, such as heat, drought, and salinity.

Here we present a detailed protocol for efficiently making homo- and heterografts between watermelon and bottle gourd, in addition to methods of tissue sampling, data generation, and data analysis, for the investigation of cold-responsive microRNAs.

MicroRNAs (miRNAs) are endogenous small non-coding RNAs of about 20 - 24 nt, known to play important roles in plant development and adaptation. There is ...