这项工作由国家自然科学基金（32370135）、中国农业科学院创新计划（CAAS-CSAL-202302）、江苏省农林职业学院科技项目（2021kj29）资助。

1.无菌水培拟南芥栽培
<ol><li>准备 拟南芥 幼苗。<ol><li>准备培养 拟南芥 幼苗培养基，其由1/2MS培养基（Murashige和Skoog）与2%（wt / vol）蔗糖和0.9%（wt / vol）琼脂组成。</li>
		<li>在凝固之前，将准备好的灭菌培养基倒入无菌方形培养皿（13 cm x 13 cm）中。避免风干以保持湿度。</li>
		<li>将 拟南芥 种子浸入装有1mL无菌水的2mL微量离心管中，在4°C下浸泡12小时以上，然后用1mL 2%（体积/体积）NaClO灭菌种子2分钟。</li>
		<li>用无菌水彻底清洗种子六次，以去除NaClO溶液。用 MS 琼脂培养基将种子播种在培养皿上，吸头为无菌 1 mL。</li>
		<li>用透气的医用胶带密封培养皿，并将它们垂直放置在光照培养箱中生长 1 周。将光照培养箱昼夜比设置为16小时/ 8小时，保持温度为23°C，湿度为40%-60%。</li>
	</ol></li>
	<li>移植拟 南芥。<ol><li>在 40 μm 孔径细胞染色剂上切 5 mm 孔并无菌。</li>
		<li>通过细胞过滤器的孔移植三株 7 天大的 拟南芥 植物，并将它们放入含有 3 mL 无菌液体 1/2 MS 培养基和 0.5% 蔗糖的 6 孔板中。</li>
		<li>将 6 孔板置于光培养箱中（图 1A）并孵育 10 天。</li>
	</ol></li>
</ol>2.细菌培养和接种
<ol><li>准备用于接种的细菌悬浮液。<ol><li>对于 贝氏芽孢杆菌，将细菌细胞接种到无菌LB培养基中，并在37°C下以170rpm振荡孵育，直至达到0.8-1.2的OD600 。</li>
		<li>通过以6000×g离心2分钟收集细菌细胞，并将细胞重悬于PBS缓冲液（2mM KH2PO 4,8mM Na2HPO4,136mM NaCl，2.6mM KCl）中。重复离心和重悬步骤 3 次，以去除 LB 培养基和细菌代谢物。</li>
		<li>将细菌细胞悬浮在新鲜的 1/2 MS 培养基中，终浓度为 OD600 0.01。将细菌悬浮液接种到培养 拟南芥 幼苗的6孔板上，将6孔板置于光照培养箱中，培养2天。</li>
	</ol></li>
</ol>3. 测量定植在根部的细菌
<ol><li>收获根组织并铺板定植细胞。 注意：所有步骤都应在gnotobiotic条件下进行<ol><li>称量 2 mL 试管并将重量记录为 W0。</li>
		<li>收获共培养的 拟南芥 根组织，并在无菌水中洗涤3次。将根放在滤纸上以去除多余的水。</li>
		<li>将根放入称量的微量离心管中，将根与管一起称取，记录为W1。</li>
		<li>向每个试管中加入 1 mL PBS，并以最大速度涡旋试管 8 分钟。</li>
		<li>将含有收集的根定植细菌细胞的悬浮液稀释至 1 x 10-1-1 x 10-4（根据细菌定植能力）。将稀释的细菌悬浮液铺在含有LB琼脂培养基的平板上，并在37°C下孵育10小时。</li>
	</ol></li>
	<li>对菌落进行计数并对数据进行归一化。<ol><li>计算LB平板上的细菌菌落。</li>
		<li>根据相应的稀释度计算CFUs，并用根鲜重（W1-W 0）对数据进行归一化。最终结果表明，接种后2天每克根定植的细菌细胞计数（图1B）。</li>
	</ol></li>
</ol>

拟南芥根际细菌定植检测

<ol>
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作者声明，他们与本文的内容没有利益冲突。

为了实现良好的可重复性，该协议的定植检测过程有四个关键步骤。首先，必须确保每个实验中接种的细菌细胞数量完全相同。其次，用无菌水控制未定植的细菌清洁强度也是必要的。第三，每个样品稀释过程在进行之前都需要进行涡旋，以使样品处于完全混合状态，以避免由于细菌的特性而导致的吸收误差，这些特性容易在微量离心管中下沉。因此，我们建议在每次吸收前使用涡旋仪混合细菌?...

有定量和定性方法可用于检测单一细菌菌株的根际定植。对于定性方法，应使用组成型表达荧光的菌株，并且应在荧光显微镜或激光共聚焦仪器1,2下检查荧光分布和强度。这些策略可以很好地反映细菌原位定植 3，但它们在定量方面不如传统的平板计数方法准确。此外，由于在显微镜下只能显示部分根区的限制，有时可能会受到主观偏见的影响。
在这里，我们描述了一种定量方法，其中包括收集定植的细菌细胞并计数板上的细菌 CFU。该方法基于稀释和铺板，通过该方法可以计算从植物根部剥离的定植菌株，并且可以计算出根部上的总定植细菌数4,5。
首先，在水培条件下培养 拟南芥 ，然后在根际中以终浓度0.01 OD600接种细菌细胞。接种后 2 天收获感染的根组织，并用无菌水洗涤以去除未定植的细菌细胞。此外，收集定植在根上的细菌细胞，在磷酸盐缓冲盐水 （PBS） 缓冲液中稀释，并接种到 Luria-Bertani （LB） 琼脂培养基上。在37°C孵育10小时后，对LB平板上的单个菌落进行计数并归一化以确定定植在根上的细菌细胞。
该方法适用性强，重复性好，更适用于根际细菌定植的准确测定。

<table border="1" fo:keep-together.within-page="1" fo:keep-with-next.within-page="always">
	<tbody>
		<tr>
			<td>6-well plate</td>
			<td>Corning</td>
			<td>3516</td>
			<td></td>
		</tr>
		<tr>
			<td>Filter cell stainer</td>
			<td>Solarbio</td>
			<td>F8200-40&#181;m</td>
			<td></td>
		</tr>
		<tr>
			<td>Microplate reader&#160;</td>
			<td>Tecan</td>
			<td>Infinite M200 PRO</td>
			<td></td>
		</tr>
		<tr>
			<td>Murashige and Skoog medium</td>
			<td>Hopebio</td>
			<td>HB8469-5</td>
			<td></td>
		</tr>
		<tr>
			<td>NaClO</td>
			<td>Alfa</td>
			<td>L14709</td>
			<td></td>
		</tr>
		<tr>
			<td>Phytagel</td>
			<td>Sigma-Aldrich</td>
			<td>P8169</td>
			<td></td>
		</tr>
		<tr>
			<td>Square petri dish</td>
			<td>Ruiai Zhengte</td>
			<td>PYM-130</td>
			<td></td>
		</tr>
		<tr>
			<td>Vortex Genie2</td>
			<td>Scientific Industries</td>
			<td>G560E</td>
			<td></td>
		</tr>
	</tbody>
</table>

measuring bacterial colonization on arabidopsis thaliana roots in hydroponic condition

测量 拟南芥 根上的细菌定植是植物-微生物相互作用研究中最常见的实验之一。为了提高可重复性，需要一种标准化的方法来测量细菌在根际中的定植。我们首先在水培条件下培养无菌 拟南芥 ，然后在根际中以 OD600 的终浓度 0.01 接种细菌细胞。接种后 2 天，收获根组织并在无菌水中洗涤 3 次，以去除未定植的细菌细胞。然后称重根部，并通过涡旋收集定植在根部上的细菌细胞。用磷酸盐缓冲盐水 （PBS） 缓冲液以梯度稀释细胞悬液，然后接种到 Luria-Bertani （LB） 琼脂培养基上。将平板在37°C下孵育10小时，然后对LB平板上的单个菌落进行计数并归一化，以指示定植在根上的细菌细胞。该方法用于在单相互作用条件下检测细菌在根际中的定植，具有良好的重现性。

为了检验该方法在 拟南芥根际中检测细菌定植能力的准确性，我们分别将 芽孢杆 菌SQR9 WT和衍生突变体 Δ8mcp 接种到 拟南芥 根际中。 Δ8mcp 是一种缺乏所有化学感受器编码基因的突变体，并且它的定植显着减少6。我们通过目前的根定植测定法在接种后 2 天测量了它们的定植。结果表明， Δ8mcp的根系定植显著减少，表明该条件和方法有效?...

Watch this Scientific Journal Video about Author Spotlight: Enhancing Rhizobacteria Colonization on Plant Roots for Improved Microbial Fertilizer Efficiency at JoVE.com

作者聚焦：增强根际细菌在植物根部的定植以提高微生物肥料效率

植物促生长根际（PGPR）在根际的定植对其促生长作用至关重要。有必要规范细菌根际定植的检测方法。在这里，我们描述了一种可重复的方法，用于量化细菌在根表面的定植。

在水培条件下测量 拟南芥 根上的细菌定植

Measuring bacterial colonization on Arabidopsis thaliana root is one of the most frequent experiments in plant-microbe interaction studies. A standardized ...

我们的研究重点是有益根际细菌与植物根系的相互作用。我们正在寻找增强有益菌定植的关键机制，从而提高田间微生物肥料的效率和稳定性。细菌在植物根系定植的方法已经得到了广泛的研究，但仍然存在问题。例如，很难对不同位点的定植进行不同的测量，我们认为在未来应用显微镜和高通量计数将有助于解决问题。我们的方案具有高度适用性和良好的可重复性，更适合于准确的根际细菌定植测定。

measuring-bacterial-colonization-on-arabidopsis-thaliana-roots

Research

JoVE Journal

Environment

Measuring Bacterial Colonization on Arabidopsis thaliana Roots in Hydroponic Condition

634 次观看.  Chinese Academy of Agricultural Sciences. 我们的研究重点是有益根际细菌与植物根系的相互作用。我们正在寻找增强有益菌定植的关键机制，从而提高田间微生物肥料的效率和稳定性。细菌在植物根系定植的方法已经得到了广泛的研究，但仍然存在问题。例如，很难对不同位点的定植进行不同的测量，我们认为在未来应用显微镜和高通量计数将有助于解决问题。我们的方案具有高度适用性和良好的可重复性，?...

视频: 作者聚焦：增强根际细菌在植物根部的定植以提高微生物肥料效率

A Push-pull Protocol to Reduce Colonization of Bird Nest Boxes by Honey Bees

Introduction of the invasive Africanized honey bee (AHB) into the Neotropics is a serious problem for many cavity nesting birds, specifically parrots. These bees select cavities that are suitable nest sites for birds, resulting in competition. The difficulty of removing bees and their defensive behavior makes a prevention protocol necessary. Here, we describe a push-pull integrated pest management protocol to deter bees from inhabiting bird boxes by applying a bird safe insecticide, permethrin, to repel bees from nest boxes, while simultaneously attracting them to pheromone-baited swarm traps. Shown here is an example experiment using Barn Owl nest boxes. This protocol successfully reduced colonization of Barn Owl nest boxes by Africanized honey bees. This protocol is flexible, allowing adjustments to accommodate a wide range of bird species and habitats. This protocol could benefit conservation efforts where AHB are located.

Preventing colonization of bird nest boxes by invasive Africanized honey bees is important for conservation efforts of nest-site limited birds. We provide an integrated pest management approach to &#34;push&#34; bees away from nest boxes with a repellant insecticide, permethrin, and &#34;pull&#34; them toward pheromone baited swarm traps.

推挽议定书蜜蜂会影响家禽的殖民化巢箱

Introduction of the invasive Africanized honey bee (AHB) into the Neotropics is a serious problem for many cavity nesting birds, specifically parrots. ...

科研

环境科学

Preparation of DMMTAV and DMDTAV Using DMAV for Environmental Applications: Synthesis, Purification, and Confirmation

Dimethylated thioarsenicals such as dimethylmonothioarsinic acid (DMMTAV) and dimethyldithioarsinic acid (DMDTAV), which are produced by the metabolic pathway of dimethylarsinic acid (DMAV) thiolation, have been recently found in the environment as well as human organs. DMMTAV and DMDTAV can be quantified to determine the ecological effects of dimethylated thioarsenicals and their stability in environmental media. The synthesis method for these compounds is unstandardized, making replicating previous studies challenging. Furthermore, there is a lack of information about storage techniques, including storage of compounds without species transformation. Moreover, because only limited information about synthesis methods is available, there may be experimental difficulties in synthesizing standard chemicals and performing quantitative analysis. The protocol presented herein provides a practically modified synthesis method for the dimethylated thioarsenicals, DMMTAV and DMDTAV, and will help in the quantification of species separation analysis using high performance liquid chromatography in conjunction with inductively coupled plasma mass spectrometry (HPLC-ICP-MS). The experimental steps of this procedure were modified by focusing on the preparation of chemical reagents, filtration methods, and storage.

Preparation of DMMTAV and DMDTAV Using DMAV for Environmental Applications: Synthesis, Purification, and Confirmation

This article presents modified experimental protocols for dimethylmonothioarsinic acid (DMMTAV) and dimethyldithioarsinic acid (DMDTAV) synthesis, inducing dimethylarsinic acid (DMAV) thiolation through mixing of DMAV, Na2S, and H2SO4. The modified protocol provides an experimental guideline, thereby overcoming limitations of the synthesis steps that could have caused experimental failures in quantitative analysis.

使用 DMAv为环境应用 DMMTAv和 DMDTAv的准备: 合成、纯化和确认

Dimethylated thioarsenicals such as dimethylmonothioarsinic acid (DMMTAV) and dimethyldithioarsinic acid (DMDTAV), which are produced by the metabolic ...

A Flexible Low Cost Hydroponic System for Assessing Plant Responses to Small Molecules in Sterile Conditions

A wide range of studies in plant biology are performed using hydroponic cultures. In this work, an in vitro hydroponic growth system designed for assessing plant responses to chemicals and other substances of interest is presented. This system is highly efficient in obtaining homogeneous and healthy seedlings of the C3 and C4 model species Arabidopsis thaliana and Setaria viridis, respectively. The sterile cultivation avoids algae and microorganism contamination, which are known limiting factors for plant normal growth and development in hydroponics. In addition, this system is scalable, enabling the harvest of plant material on a large scale with minor mechanical damage, as well as the harvest of individual parts of a plant if desired. A detailed protocol demonstrating that this system has an easy and low-cost assembly, as it uses pipette racks as the main platform for growing plants, is provided. The feasibility of this system was validated using Arabidopsis seedlings to assess the effect of the drug AZD-8055, a chemical inhibitor of the target of rapamycin (TOR) kinase. TOR inhibition was efficiently detected as early as 30 min after an AZD-8055 treatment in roots and shoots. Furthermore, AZD-8055-treated plants displayed the expected starch-excess phenotype. We proposed this hydroponic system as an ideal method for plant researchers aiming to monitor the action of plant inducers or inhibitors, as well as to assess metabolic fluxes using isotope-labeling compounds which, in general, requires the use of expensive reagents.

A simple, versatile, and low-cost in vitro hydroponic system was successfully optimized, enabling large-scale experiments under sterile conditions. This system facilitates the application of chemicals in a solution and their efficient absorption by roots for molecular, biochemical, and physiological studies.

一种灵活的低成本水培系统在无菌条件下评价植物对小分子的响应

A wide range of studies in plant biology are performed using hydroponic cultures. In this work, an in vitro hydroponic growth system designed for ...

Isolation and Analysis of Microbial Communities in Soil, Rhizosphere, and Roots in Perennial Grass Experiments

Plant and soil microbiome studies are becoming increasingly important for understanding the roles microorganisms play in agricultural productivity. The purpose of this manuscript is to provide detail on how to rapidly sample soil, rhizosphere, and endosphere of replicated field trials and analyze changes that may occur in the microbial communities due to sample type, treatment, and plant genotype. The experiment used to demonstrate these methods consists of replicated field plots containing two, pure, warm-season grasses (Panicum virgatum and Andropogon gerardii) and a low-diversity grass mixture (A. gerardii, Sorghastrum nutans, and Bouteloua curtipendula). Briefly, plants are excavated, a variety of roots are cut and placed in phosphate buffer, and then shaken to collect the rhizosphere. Roots are brought to the laboratory on ice and surface sterilized with bleach and ethanol (EtOH). The rhizosphere is filtered and concentrated by centrifugation. Excavated soil from around the root ball is placed into plastic bags and brought to the lab where a small amount of soil is taken for DNA extractions. DNA is extracted from roots, soil, and rhizosphere and then amplified with primers for the V4 region of the 16S rRNA gene. Amplicons are sequenced, then analyzed with open access bioinformatics tools. These methods allow researchers to test how the microbial community diversity and composition varies due to sample type, treatment, and plant genotype. Using these methods along with statistical models, the representative results demonstrate there are significant differences in microbial communities of roots, rhizosphere, and soil. Methods presented here provide a complete set of steps for how to collect field samples, isolate, extract, quantify, amplify, and sequence DNA, and analyze microbial community diversity and composition in replicated field trials.

Excavation of plant roots from the field as well as processing of samples into endosphere, rhizosphere, and soil are described in detail, including DNA extraction and data analysis methods. This paper is designed to enable other laboratories to use these techniques for the study of soil, endosphere, and rhizosphere microbiomes.

多年生草试验中土壤、根际和根系微生物群落的分离与分析

Plant and soil microbiome studies are becoming increasingly important for understanding the roles microorganisms play in agricultural productivity. The ...

Measuring Hypopharyngeal Gland Acinus Size in Honey Bee (Apis mellifera) Workers

The nurse hypopharyngeal glands produce the protein fraction of the worker and royal jelly that is fed to developing larvae and queens. These paired glands that are located in the head of the bee are highly sensitive to the quantity and quality of pollen and pollen substitutes that the nurse bee consumes. The glands get smaller when nurses are fed deficient diets and are large when they are fed complete diets. Because nurse hypopharyngeal gland size is a robust indicator of nurse nutrition, it is essential that those studying honey bee nutrition know how to measure these glands. Here, we provide detailed methods for dissecting, staining, imaging, and measuring nurse bee hypopharyngeal glands. We present comparisons of unstained and stained tissue and data that were used to study the impact of pollen on gland size. This method has been used to test how diet impacts hypopharyngeal gland size but has further use for understanding the role of these glands in hive health.

Measuring Hypopharyngeal Gland Acinus Size in Honey Bee Apis mellifera Workers

Hypopharyngeal gland acinus size is a robust measure of nurse honey bee nutrition. Here, we provide a detailed protocol for dissecting, staining, imaging, and measuring nurse bee hypopharyngeal gland acini.

蜂蜜蜂 (api 蜜蜂) 中下咽腺性腺泡大小的测定

The nurse hypopharyngeal glands produce the protein fraction of the worker and royal jelly that is fed to developing larvae and queens. These paired ...

An Induction System for Clustered Stomata by Sugar Solution Immersion Treatment in Arabidopsis thaliana Seedlings

Stomatal movement mediates plant gas exchange, which is essential for photosynthesis and transpiration. Stomatal opening and closing are accomplished by a significant increase and decrease in guard cell volume, respectively. Because shuttle transport of ions and water occurs between guard cells and larger neighboring epidermal cells during stomatal movement, the spaced distribution of plant stomata is considered an optimal distribution for stomatal movement. Experimental systems for perturbing the spaced pattern of stomata are useful to examine the spacing pattern's significance. Several key genes associated with the spaced stomatal distribution have been identified, and clustered stomata can be experimentally induced by altering these genes. Alternatively, clustered stomata can be also induced by exogenous treatments without genetic modification. In this article, we describe a simple induction system for clustered stomata in Arabidopsis thaliana seedlings by immersion treatment with a sucrose-containing medium solution. Our method is easy and directly applicable to transgenic or mutant lines. Larger chloroplasts are presented as a cell biological hallmark of sucrose-induced clustered guard cells. In addition, a representative confocal microscopic image of cortical microtubules is shown as an example of intracellular observation of clustered guard cells. The radial orientation of cortical microtubules is maintained in clustered guard cells as in spaced guard cells in control conditions.

An Induction System for Clustered Stomata by Sugar Solution Immersion Treatment in Arabidopsis thaliana Seedlings

The goal of this protocol is to demonstrate how to induce clustered stomata in cotyledons of Arabidopsis thaliana seedlings by immersion treatment with a sugar-containing medium solution and how to observe intracellular structures such as chloroplasts and microtubules in the clustered guard cells using confocal laser microscopy.

拟南芥幼苗糖溶液浸入治疗的聚集性植物诱导系统

Stomatal movement mediates plant gas exchange, which is essential for photosynthesis and transpiration. Stomatal opening and closing are accomplished by a ...

Shootward Movement of CFDA Tracer Loaded in the Bottom Sink Tissues of Arabidopsis

The symplastic tracer 5(6)-carboxyfluorescein diacetate (CFDA) has been widely applied in living plants to demonstrate the intercellular connection, phloem transport and vascular patterning. This protocol shows bottom-to-top carboxyfluorescein (CF) movement in the Arabidopsis by using the root-cutting and the hypocotyl-pinching procedure respectively. These two different procedures result in different efficiencies of CF movement: about 91% appearance of CF in the shoots with the hypocotyl-pinching procedure, whereas only about 70% appearance of CF with the root-cutting procedure. The simple change of loading sites, resulting in significant changes in the mobile efficiency of this symplastic dye, suggests CF movement might be subject to the symplastic regulation, most probably by the root-hypocotyl junction.

Shootward Movement of CFDA Tracer Loaded in the Bottom Sink Tissues of Arabidopsis

The goal of this protocol is to show how to load the CFDA into different sites of the bottom parts of Arabidopsis. We then present the resulting distribution pattern of CF in the shoots.

美国食品药品监督管理局追踪者在拟南芥底部水槽组织中的射击运动

The symplastic tracer 5(6)-carboxyfluorescein diacetate (CFDA) has been widely applied in living plants to demonstrate the intercellular connection, ...

Measuring Phosphorus Release in Laboratory Microcosms for Water Quality Assessment

Phosphorus (P) is a critical limiting nutrient in agroecosystems requiring careful management to reduce transport risk to aquatic environments. Routine laboratory measures of P bioavailability are based on chemical extractions performed on dried samples under oxidizing conditions. While useful, these tests are limited with respect to characterizing P release under prolonged water saturation. Labile orthophosphate bound to oxidized iron and other metals can rapidly desorb to solution in reducing environments, increasing P mobilization risk to surface runoff and groundwater. To better quantify P desorption potential and mobility during extended saturation, a laboratory microcosm method was developed based on repeated sampling of porewater and overlying floodwater over time. The method is useful for quantifying P release potential from soils and sediments varying in physicochemical properties and can improve site-specific P mitigation efforts by better characterizing P release risk in hydrologically active areas. Advantages of the method include its ability to simulate in situ dynamics, simplicity, low cost, and flexibility.

Accurate quantification of phosphorus (P) desorption potential in saturated soils and sediments is important for P modeling and transport mitigation efforts. To better account for in situ soil-water redox dynamics and P mobilization under prolonged saturation, a simple approach was developed based on repeated sampling of laboratory microcosms.

测量实验室微量微生物中的磷释放,用于水质评估

Phosphorus (P) is a critical limiting nutrient in agroecosystems requiring careful management to reduce transport risk to aquatic environments. Routine ...

A Method to Preserve Wetland Roots and Rhizospheres for Elemental Imaging

Roots extensively interact with their soil environment but visualizing such interactions between roots and the surrounding rhizosphere is challenging. The rhizosphere chemistry of wetland plants is particularly challenging to capture because of steep oxygen gradients from the roots to the bulk soil. Here a protocol is described that effectively preserves root structure and rhizosphere chemistry of wetland plants through slam-freezing and freeze drying. Slam-freezing, where the sample is frozen between copper blocks pre-cooled with liquid nitrogen, minimizes root damage and sample distortion that can occur with flash-freezing while still minimizing chemical speciation changes. While sample distortion is still possible, the ability to obtain multiple samples quickly and with minimal cost increases the potential to obtain satisfactory samples and optimizes imaging time. The data show that this method is successful in preserving reduced arsenic species in rice roots and rhizospheres associated with iron plaques. This method can be adopted for studies of plant-soil relationships in a wide variety of wetland environments that span concentration ranges from trace-element cycling to phytoremediation applications.

We describe a protocol to sample, preserve, and section intact roots and the surrounding rhizosphere soil from wetland environments using rice (Oryza sativa L.) as a model species. Once preserved, the sample can be analyzed using elemental imaging techniques, such as synchrotron X-ray fluorescence (XRF) chemical speciation imaging.

元素成像保护湿地根和岩石圈的方法

Roots extensively interact with their soil environment but visualizing such interactions between roots and the surrounding rhizosphere is challenging. The ...

Using Changes in Leaf Transmission to Investigate Chloroplast Movement in Arabidopsis thaliana

Chloroplast movement in leaves has been shown to help minimize photoinhibition and increase growth under certain conditions. Much can be learned about chloroplast movement by studying the chloroplast positioning in leaves using e.g., confocal fluorescence microscopy, but access to this type of microscopy is limited. This protocol describes a method that uses the changes in leaf transmission as a proxy for chloroplast movement. If chloroplasts are spread out in order to maximize light interception, the transmission will be low. If chloroplasts move towards the anticlinal cell walls to avoid light, the transmission will be higher. This protocol describes how to use a straightforward, home-built instrument to expose leaves to different blue light intensities and quantify the dynamic changes in leaf transmission. This approach allows researchers to quantitatively describe chloroplast movement in different species and mutants, study the effects of chemicals and environmental factors on it, or screen for novel mutants e.g., to identify missing components in the process that leads from light perception to the movement of chloroplasts.

Using Changes in Leaf Transmission to Investigate Chloroplast Movement in Arabidopsis thaliana

Many plant species change the positioning of chloroplasts to optimize light absorption. This protocol describes how to use a straightforward, home-built instrument to investigate chloroplast movement in Arabidopsis thaliana leaves using changes in the transmission of light through a leaf as a proxy.

利用叶片传播的变化来研究拟南芥的叶绿体运动

Chloroplast movement in leaves has been shown to help minimize photoinhibition and increase growth under certain conditions. Much can be learned about ...

在水培条件下测量 拟南芥 根上的细菌定植

在水培条件下测量拟南芥根上的细菌定植