Name: enhancement of the initial growth rate of agricultural plants by using static magnetic fields
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Description: Watch this Scientific Journal Video about Enhancement of the Initial Growth Rate of Agricultural Plants by Using Static Magnetic Fields at JoVE.com

This study received supported from the National Research Foundation of Korea (NRF) (2011-0012728). A poster presenting this study was awarded the Best Poster Award by the Korean Society of Applied Biological Sciences (KSABC).

1. Initial Settings
<ol>
	<li>Agricultural Plant Species
	<ol>
		<li>Use Garden Balsam (Impatiens balsamina), Mizuna (Brassica rapa var. japonica), Komatsuna (Brassica rapa var. perviridis), and Mescluns (Lepidium sativum) seeds. 
		NOTE: Impatiens balsamina (Garden Balsam or Rose Balsam) is a species native to India; a few members are also located in Myanmar. Komatsuna (Brassica rapa var. perviridis or komatsuna) is a variant of the same spec...

<ol>
	<li>Martin, F. W. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=In+vitro+measurement+of+pollen+tube+growth+inhibition.">In vitro measurement of pollen tube growth inhibition.</a> Plant Physiol. 49, 924-925 (1972).</li><li>Pfahler, P. L. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=In+vitro+germination+characteristics+of+maize+pollen+to+detect+biological+activity+of+environmental+pollutants.">In vitro germination characteristics of maize pollen to detect biological activity of environmental pollutants.</a> Environ Health Perspect. 37, 125-132 (1981).</li><li>Yao, Z., Tan, X., Du, H., Luo, B., Liu, Z. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=A+high-current+microwave+ion+source+with+permanent+magnet+and+its+beam+emittance+measurement.">A high-current microwave ion source with permanent magnet and its beam emittance measurement.</a> Rev Sci Instrum. 79, 073304 (2008).</li><li>Hendrickson, C. L., Drader, J. J., Laude, D. A., Guan, S., Marshall, A. G. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Fourier+transform+ion+cyclotron+resonance+mass+spectrometry+in+a+20+T+resistive+magnet.">Fourier transform ion cyclotron resonance mass spectrometry in a 20 T resistive magnet.</a> Rapid Commun Mass Spectrom. 10, 1829-1832 (1996).</li><li>Namba, K., Sasao, A., Shibusawa, S. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=EFFECT+OF+MAGNETIC+FIELD+ON+GERMINATION+AND+PLANT+GROWTH.">EFFECT OF MAGNETIC FIELD ON GERMINATION AND PLANT GROWTH.</a> Acta Hort. 399, 143-148 (1995).</li><li>Hirota, N., Nakagawa, J., Kitazawa, K. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Effects+of+a+magnetic+field+on+the+germination+of+plants.">Effects of a magnetic field on the germination of plants.</a> Journals of Applied Physics. 85, 5717-5719 (1999).</li><li>Penuelas, J., Llusia, J., Martinez, B., Fontcuberta, J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Diamagnetic+Susceptibility+and+Root+Growth+Responses+to+Magnetic+Fields+in+Lens+culinaris,+Glycine+soja,+and+Triticum+aestivum.">Diamagnetic Susceptibility and Root Growth Responses to Magnetic Fields in Lens culinaris, Glycine soja, and Triticum aestivum.</a> Electromagnetic Biology and Medicine. 23, 97-112 (2004).</li><li>Carbonell, M. V., Martinez, E., Amaya, J. M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Stimulation+of+germination+in+rice+(Oryza+Sativa+L.)+by+a+static+magnetic+field.">Stimulation of germination in rice (Oryza Sativa L.) by a static magnetic field.</a> Electro- and Magnetobiology. 19, 121-128 (2000).</li><li>Oakley, R. V., Wang, Y. S., Ramakrishna, W., Harding, S. A., Tsai, C. J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Differential+expansion+and+expression+of+alpha-+and+beta-tubulin+gene+families+in+Populus.">Differential expansion and expression of alpha- and beta-tubulin gene families in Populus.</a> Plant Physiol. 145, 961-973 (2007).</li><li>Hoson, T., Matsumoto, S., Soga, K., Wakabayashi, K. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Cortical+microtubules+are+responsible+for+gravity+resistance+in+plants.">Cortical microtubules are responsible for gravity resistance in plants.</a> Plant Signal Behav. 5, 752-754 (2010).</li><li>Kim, S., Im, W. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Static+magnetic+fields+inhibit+proliferation+and+disperse+subcellular+localization+of+gamma+complex+protein3+in+cultured+C2C12+myoblast+cells.">Static magnetic fields inhibit proliferation and disperse subcellular localization of gamma complex protein3 in cultured C2C12 myoblast cells.</a> Cell Biochem Biophys. 57, 1-8 (2010).</li><li>Benjamini, Y. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Opening+the+Box+of+a+Boxplot.">Opening the Box of a Boxplot.</a> The American Statistician. 42, 257-262 (1988).</li></ol>

In all conditions, magnets should be applied under the petri dish. This study examined the influence of magnetic fields on growth rate of seeds for several agricultural species, with focus on Garden Balsam as a representative of agricultural plants. For instance, tubulin staining was performed on Garden Balsam to evaluate the molecular-level changes in root and stem skeletal micro-structures suggesting influence of the magnetic field in length proliferation. Both the N and S poles of the magnet were applied in a long-ter...

Germination is the growth of a plant that results in the formation of the seedling1. Under certain conditions, seed germination begins and the embryonic tissues resume growth. It begins with hydration to the seed in order to activate enzymes for germination. Seeds can be induced to germinate in vitro (in a Petri dish or test tube)1,2.
Static magnetic fields are special forces that cause movements of molecules with ionic charges by way of the Lorentz force3,4. Lorentz force is formed when an ionized or charged object moves under a magnetic field. Every material is formed with atoms which are composed of electrons and protons. When magnetic fields become present, whether it is static or alternating, it affects the movement of charged material. This also applies to plants and water molecules, which affects the intracellular molecule condition. In a previous study, electromagnetic coils were used to generate pulsed magnetic fields, and &#39;Komatsuna&#39; plants were chosen as the subjects5. In the present study, magnet generated static magnetic fields were used to give a similar but different effects as an expansion study of Lorentz force.
The frequency of the magnetic field, rather than its polarity, is a crucial factor for plant germination. Previous studies have suggested that maximum germination rates were 20% higher than control when the frequency of the magnetic field was approximately 10 Hz. When the field was removed in a retrograde manner, the growth rate was impaired5. Static magnetic fields have a considerable effect on the initial growth6-8, primarily on germination6 and root growth7.
In the present study, we used static magnets to examine the possibility of regulating the growth of agricultural plants by using magnetic fields. In particular, we aimed to determine whether certain conditions of magnetic field application could increase the growth rates to higher levels than those mentioned in the literature. Furthermore, if the initial germination of plants can be successfully increased using a magnetic field, the use of chemical fertilizers can be avoided.

<table border="0" cellpadding="0" cellspacing="0" width="646">
	<tbody>
		<tr height="21">
			<td height="21" style="height:21px;width:216px;">Static magnets</td>
			<td style="width:144px;">JIM</td>
			<td style="width:119px;">N/A</td>
			<td style="width:167px;">2000Gauss</td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;">2% horse serum/1% bovine serum albumin/0.1% Triton X-100</td>
			<td>Sigma-Aldrich</td>
			<td style="width:119px;">Merged with 55514</td>
			<td>Blocking buffer</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">Primary antibody</td>
			<td>Santa Cruz Biotechnology</td>
			<td style="width:119px;">sc-8035</td>
			<td>a-Tubulin</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:216px;">Secondary antibody</td>
			<td>Santa Cruz Biotechnology</td>
			<td style="width:119px;">sc-2010</td>
			<td>FITC-conjugated anti-mouse IgG</td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;">time lapse photographic techniques</td>
			<td style="width:144px;">Manually controlled</td>
			<td style="width:119px;">N/A</td>
			<td>ISO value 400 &#38; aperture F 3.2</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:216px;">Sony Vegas Pro 13.0</td>
			<td style="width:144px;">Sony</td>
			<td style="width:119px;">N/A</td>
			<td style="width:167px;">N/A</td>
		</tr>
	</tbody>
</table>

enhancement of the initial growth rate of agricultural plants by using static magnetic fields

Electronic devices and high-voltage wires induce magnetic fields. A magnetic field of 1,300-2,500 Gauss (0.2 Tesla) was applied to Petri dishes containing seeds of Garden Balsam (Impatiens balsamina), Mizuna (Brassica rapa var. japonica), Komatsuna (Brassica rapa var. perviridis), and Mescluns (Lepidium sativum). We applied magnets under the culture dish. During the 4 days of application, we observed that the stem and root length increased. The group subjected to magnetic field treatment (n = 10) showed a 1.4 times faster rate of growth compared with the control group (n = 11) in a total of 8 days (p &#60;0.0005). This rate is 20% higher than that reported in previous studies. The tubulin complex lines did not have connecting points, but connecting points occur upon the application of magnets. This shows complete difference from the control, which means abnormal arrangements. However, the exact cause remains unclear. These results of growth enhancement of applying magnets suggest that it is possible to enhance the growth rate, increase productivity, or control the speed of germination of plants by applying static magnetic fields. Also, magnetic fields can cause physiological changes in plant cells and can induce growth. Therefore, stimulation with a magnetic field can have possible effects that are similar to those of chemical fertilizers, which means that the use of fertilizers can be avoided.

Tubulin staining showed dispersed or thinned structures in plants grown in the presence of the magnet compared to the control (Figure 2). Moreover, 7 day time-lapse studies with agricultural plants including Komatsuna (Brassica rapa var. perviridis) and Mescluns (Lepidium sativum) indicated that a magnet derived static magnetic field increases the initial growth of these plants (Figure 3).
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Watch this Scientific Journal Video about Enhancement of the Initial Growth Rate of Agricultural Plants by Using Static Magnetic Fields at JoVE.com

Enhancement of the Initial Growth Rate of Agricultural Plants by Using Static Magnetic Fields

The goal of this protocol is to demonstrate the acceleration of the initial growth rate of plants by applying static magnetic fields with no external energy.

Electronic devices and high-voltage wires induce magnetic fields. A magnetic field of 1,300-2,500 Gauss (0.2 Tesla) was applied to Petri dishes containing ...

The overall goal of this procedure is to facilitate the growth rate of plants using static magnetic fields. This method can help answer key questions in agriculture and the nutritional medicine field, that address techniques in food production. The main advantage of this technique is that it does not use any energy or fertilizers.To begin, culture impatiens balsamina or garden balsam seeds, by placing them on a cellulose towel in separate 100 millimeter diameter petri dishes. Then, immerse the towel and seeds in triple distilled water. Measure and confirm that the indoor lab temperature is 18 to 25 degrees celsius, with humidity ranging from 65 to 75%Place three magnets of 1, 750 plus or minus 350 Gauss, underneath the garden balsam dish, with a distance of two to four millimeters between the seeds and the magnets.Next, after placing three magnets under a second dish of seeds, stack two magnets with the north side facing up for the top magnet and the south side facing up for the bottom magnet. Then, place the two magnets together on the bottom of the garden balsam culture plate. To generate time-lapse images of plant growth, after setting up a digital camera to photograph the plant according to the text protocol, place size markers, such as a Canadian quarter and American penny and a centimeter ruler on the side of the field of view.Then, collect 700 to 900 pictures for seven to 10 days. After using movie making software to create a time-lapse movie with the images, according to the text protocol, run the movie to verify it. After plating seeds on a cellulose towel, as demonstrated earlier in this video, place two magnets with the north pole facing up on the bottom of the 100 millimeter plate and incubate for 48 hours.To stain the plants, place the entire impatiens SPP double flower plant into 4%paraformaldehyde and 0, 1 molar fast feed buffer and fix the plant for 15 minutes. Transfer the plant sample into a blocking buffer and incubate for two hours. Then, immerse the impatiens sample in PDS for 15 minutes to wash it.Following the wash, add anti-alpha-tubulin primary antibodies and incubate at four degrees celsius overnight. The next day, transfer the sample to PBS for 10 minutes. Then, place the plant in FITC-conjugated anti-mouse IgG and incubate in the dark at 25 degrees celsius for two hours.After the incubation, immerse the sample in PBS in the well of a 24 well plate and place a cover slip on the entire sample. Then, use a fluorescence microscope to observe turbulent orientation. This figure shows that under dark growth conditions, garden balsam plants only exhibited a marginal increase in growth rate when exposed to a static magnetic field.However, the magnetic field was associated with an increased growth rate when the plants were grown under light. On day three, the difference in height between the magnet exposed plants and the controls was statistically significant. And the differences continued through day seven.These fluorescence images demonstrate the turbulent developed into dispersed or thin structures in plants growing in the presence of magnets, compared to the control plants. Once mastered, this technique can be done in 72 hours if it is performed properly. While attempting this procedure, it's important to remember to control the intensity of magnets.Following this procedure, apply to other model organisms can be performed in order to answer additional questions, such as rhe genetic basis of growth enhancement in a field. After its development, this technique paved the way for researchers in the field of nutritional medicine to explore a key regulator of nutrition enrichment and plant growth. After watching this video, you should have a good understanding of how to enhance initial growth of a plant using magnets.Don't forget that working in direct contact with magnets can be extremely hazardous and conditions such as humidity, can cause decay of iron and should always be taken into account while performing this procedure.

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Measurement of Greenhouse Gas Flux from Agricultural Soils Using Static Chambers

Measurement of greenhouse gas (GHG) fluxes between the soil and the atmosphere, in both managed and unmanaged ecosystems, is critical to understanding the biogeochemical drivers of climate change and to the development and evaluation of GHG mitigation strategies based on modulation of landscape management practices. The static chamber-based method described here is based on trapping gases emitted from the soil surface within a chamber and collecting samples from the chamber headspace at regular intervals for analysis by gas chromatography. Change in gas concentration over time is used to calculate flux. This method can be utilized to measure landscape-based flux of carbon dioxide, nitrous oxide, and methane, and to estimate differences between treatments or explore system dynamics over seasons or years. Infrastructure requirements are modest, but a comprehensive experimental design is essential. This method is easily deployed in the field, conforms to established guidelines, and produces data suitable to large-scale GHG emissions studies.

This article showcases the static chamber-based method for measurement of greenhouse gas flux from soil systems. With relatively modest infrastructure investments, measurements may be obtained from multiple treatments/locations and over timeframes ranging from hours to years.

Measurement of greenhouse gas (GHG) fluxes between the soil and the atmosphere, in both managed and unmanaged ecosystems, is critical to understanding the ...

The Use of High-resolution Infrared Thermography (HRIT) for the Study of Ice Nucleation and Ice Propagation in Plants

Freezing events that occur when plants are actively growing can be a lethal event, particularly if the plant has no freezing tolerance. Such frost events often have devastating effects on agricultural production and can also play an important role in shaping community structure in natural populations of plants, especially in alpine, sub-arctic, and arctic ecosystems. Therefore, a better understanding of the freezing process in plants can play an important role in the development of methods of frost protection and understanding mechanisms of freeze avoidance. Here, we describe a protocol to visualize the freezing process in plants using high-resolution infrared thermography (HRIT). The use of this technology allows one to determine the primary sites of ice formation in plants, how ice propagates, and the presence of ice barriers. Furthermore, it allows one to examine the role of extrinsic and intrinsic nucleators in determining the temperature at which plants freeze and evaluate the ability of various compounds to either affect the freezing process or increase freezing tolerance. The use of HRIT allows one to visualize the many adaptations that have evolved in plants, which directly or indirectly impact the freezing process and ultimately enables plants to survive frost events.

The Use of High-resolution Infrared Thermography HRIT for the Study of Ice Nucleation and Ice Propagation in Plants

Here we present a protocol that allows one to visualize sites of ice formation and avenues of ice propagation in plants utilizing high resolution infrared thermography (HRIT).

Freezing events that occur when plants are actively growing can be a lethal event, particularly if the plant has no freezing tolerance. Such frost events ...

Continuous Instream Monitoring of Nutrients and Sediment in Agricultural Watersheds

Pollutant concentrations and loads in watersheds vary considerably with time and space. Accurate and timely information on the magnitude of pollutants in water resources is a prerequisite for understanding the drivers of the pollutant loads and for making informed water resource management decisions. The commonly used &#34;grab sampling&#34; method provides the concentrations of pollutants at the time of sampling (i.e., a snapshot concentration) and may under- or overpredict the pollutant concentrations and loads. Continuous monitoring of nutrients and sediment has recently received more attention due to advances in computing, sensing technology, and storage devices. This protocol demonstrates the use of sensors, sondes, and instrumentation to continuously monitor in situ nitrate, ammonium, turbidity, pH, conductivity, temperature, and dissolved oxygen (DO) and to calculate the loads from two streams (ditches) in two agricultural watersheds. With the proper calibration, maintenance, and operation of sensors and sondes, good water quality data can be obtained by overcoming challenging conditions such as fouling and debris buildup. The method can also be used in watersheds of various sizes and characterized by agricultural, forested, and/or urban land.

With the advancement of technology and the rise in end-user expectations, the need and use of higher temporal resolution data for pollutant load estimation has increased. This protocol describes a method for continuous in situ water quality monitoring to obtain higher temporal resolution data for informed water resource management decisions.

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Methodology for Developing Life Tables for Sessile Insects in the Field Using the Whitefly, Bemisia tabaci, in Cotton As a Model System

Life tables provide a means of measuring the schedules of birth and death from populations over time. They also can be used to quantify the sources and rates of mortality in populations, which has a variety of applications in ecology, including agricultural ecosystems. Horizontal, or cohort-based, life tables provide for the most direct and accurate method of quantifying vital population rates because they follow a group of individuals in a population from birth to death. Here, protocols are presented for conducting and analyzing cohort-based life tables in the field that takes advantage of the sessile nature of the immature life stages of a global insect pest, Bemisia tabaci. Individual insects are located on the underside of cotton leaves and are marked by drawing a small circle around the insect with a non-toxic pen. This insect can then be observed repeatedly over time with the aid of hand lenses to measure development from one stage to the next and to identify stage-specific causes of death associated with natural and introduced mortality forces. Analyses explain how to correctly measure multiple mortality forces that act contemporaneously within each stage and how to use such data to provide meaningful population dynamic metrics. The method does not directly account for adult survival and reproduction, which limits inference to dynamics of immature stages. An example is presented that focused on measuring the impact of bottom-up (plant quality) and top-down (natural enemies) effects on the mortality dynamics of B. tabaci in the cotton system.

Methodology for Developing Life Tables for Sessile Insects in the Field Using the Whitefly, Bemisia tabaci, in Cotton As a Model System

Life tables allow quantification of the sources and rates of mortality in insect populations and contribute to understanding, predicting and manipulating population dynamics in agroecosystems. Methods for conducting and analyzing cohort-based life tables in the field for an insect with sessile immature life stages are presented.

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Development of New Methods for Quantifying Fish Density Using Underwater Stereo-video Tools

The use of video camera systems in ecological studies of fish continues to gain traction as a viable, non-extractive method of measuring fish lengths and estimating fish abundance. We developed and implemented a rotating stereo-video camera tool that covers a full 360 degrees of sampling, which maximizes sampling effort compared to stationary camera tools. A variety of studies have detailed the ability of static, stereo-camera systems to obtain highly accurate and precise measurements of fish; the focus here was on the development of methodological approaches to quantify fish density using rotating camera systems. The first approach was to develop a modification of the metric MaxN, which typically is a conservative count of the minimum number of fish observed on a given camera survey. We redefine MaxN to be the maximum number of fish observed in any given rotation of the camera system. When precautions are taken to avoid double counting, this method for MaxN may more accurately reflect true abundance than that obtained from a fixed camera. Secondly, because stereo-video allows fish to be mapped in three-dimensional space, precise estimates of the distance-from-camera can be obtained for each fish. By using the 95% percentile of the observed distance from camera to establish species-specific areas surveyed, we account for differences in detectability among species while avoiding diluting density estimates by using the maximum distance a species was observed. Accounting for this range of detectability is critical to accurately estimate fish abundances. This methodology will facilitate the integration of rotating stereo-video tools in both applied science and management contexts.

We describe a new method for counting fishes, and estimating relative abundance (MaxN) and fish density using rotating stereo-video camera systems. We also demonstrate how to use distance from camera (Z distance) to estimate species-specific detectability.

The use of video camera systems in ecological studies of fish continues to gain traction as a viable, non-extractive method of measuring fish lengths and ...

Assessment of Methane and Nitrous Oxide Fluxes from Paddy Field by Means of Static Closed Chambers Maintaining Plants Within Headspace

This protocol describes the measurement of greenhouse gas (GHG) emissions from paddy soils using the static closed chamber technique. This method is based on the diffusion theory. A known volume of air overlaying a defined soil area is enclosed within a parallelepiped cover (named &#34;chamber&#34;), for a defined period of time. During this enclosure period, gases (methane (CH4) and nitrous oxide (N2O)) move from soil pore air near their microbial source (i.e., methanogens, nitrifiers, denitrifiers) to the chamber headspace, following a natural concentration gradient. Fluxes are then estimated from chamber headspace concentration variations sampled at regular intervals throughout the enclosure and then analyzed with gas chromatography. Among the techniques available for GHG measurement, the static closed chamber method is suitable for plot experiments, as it does not require large homogenously treated soil areas. Furthermore, it is manageable with limited resources and can identify relationships among ecosystem properties, processes, and fluxes, especially when combined with GHG driving force measurements. Nevertheless, with respect to the micrometeorological method, it causes a minimal but still unavoidable soil disturbance, and allows a minor temporal resolution. Several phases are key to the method implementation: i) chamber design and deployment, ii) sample handling and analyses, and iii) flux estimation. Technique implementation success in paddy fields demands adjustments for field flooding during much of the cropping cycle, and for rice plant maintenance within the chamber headspace during measurements. Therefore, the additional elements to be considered with respect to the usual application of non-flooded agricultural soils consist of devices for: i) avoiding any unintended water disturbance that could overestimate fluxes, and ii) including rice plants within the chamber headspace to fully consider gases emitted through aerenchyma transportation.

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The interaction and sedimentation of the clay and bacterial cells within the marine realm, observed in natural environments, can be best investigated in a controlled lab environment. Here, we describe a detailed protocol, which outlines a novel method for measuring the sedimentation rate of clay and cyanobacterial floccules.

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Choice and No-Choice Bioassays to Study the Pupation Preference and Emergence Success of Ectropis grisescens

Here, we present a protocol to investigate the pupation preference of mature larvae of Ectropis grisescens in response to soil factors (e.g., substrate type and moisture content) using choice bioassays. We also present a protocol of no-choice bioassays to determine the factors that affect the pupation behaviors and survivorship of E. grisescens.

Many insects live above the ground as larvae and adults and as pupate below the ground. Compared to the above-ground stages of their life cycles, less ...

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 ...

Visualizing Efficacy of Pesticides Against Disease Vector Mosquitoes in the Field

Efficacy of public health pesticides targeting nuisance and disease-vector insects such as mosquitoes, sand flies, and filth-breeding flies is not uniform across ecological zones. To best protect public and veterinary health from these insects, the environmental limitations of pesticides need to be investigated to inform effective use of the most appropriate pesticide formulations and techniques. We have developed a research program to evaluate combinations of pesticides, pesticide application equipment, and application techniques in hot-arid desert, hot-humid tropical, warm and cool temperate, and urban locations to derive pesticide use guidelines specific to target insect and environment. To these ends we designed a system of protocols to support efficient, cost-effective, portable, and standardized evaluation of a diverse range of pesticides and equipment across multiple environments. At the core of these protocols is the use of an array of small cages with colony-reared sentinel mosquitoes (adults and immatures) and sand flies (adults), strategically arranged in natural habitats and exposed to pesticide spray. Spatial and temporal patterns of pesticide efficacy are derived from percent mortality in sentinel cages, then mapped and visualized in a geographic information system. Maps of sentinel mortality data may be statistically compared to evaluate relative efficacy of a pesticide across multiple environments, or to study multiple pesticides in a single environment. Protocols may be modified to accommodate a variety of scenarios, including, for example, the vertical orientation of sentinels in canopy habitats or simultaneous testing of ground and aerial application methods.

The efficacy of public health pesticides targeting nuisance and disease-vector insects is not uniform across different ecological zones. Here we present a system of techniques using captive vector insects as sentinels for pesticide efficacy to derive electronic maps supporting the standard evaluation of pesticides across multiple environments.

Efficacy of public health pesticides targeting nuisance and disease-vector insects such as mosquitoes, sand flies, and filth-breeding flies is not uniform ...