Magnesium Limitation Leads to Transcriptional Down-Tuning of Auxin Synthesis, Transport, and Signaling in the Tomato Root

Magnesium (Mg) deficiency is becoming a widespread limiting factor for crop production. How crops adapt to Mg limitation remains largely unclear at the molecular level. Using hydroponic-cultured tomato seedlings, we found that total Mg2+ content significantly decreased by ∼80% under Mg limitation while K+ and Ca2+ concentrations increased. Phylogenetic analysis suggested that Mg transporters (MRS2/MGTs) constitute a previously uncharacterized 3-clade tree in planta with two rounds of asymmetric duplications, providing evolutionary evidence for further molecular investigation. In adaptation to internal Mg deficiency, the expression of six representative MGTs (two in the shoot and four in the root) was up-regulated in Mg-deficient plants. Contradictory to the transcriptional elevation of most of MGTs, Mg limitation resulted in the ∼50% smaller root system. Auxin concentrations particularly decreased by ∼23% in the Mg-deficient root, despite the enhanced accumulation of gibberellin, cytokinin, and ABA. In accordance with such auxin reduction was overall transcriptional down-regulation of thirteen genes controlling auxin biosynthesis (TAR/YUCs), transport (LAXs, PINs), and signaling (IAAs, ARFs). Together, systemic down-tuning of gene expression in the auxin signaling pathway under Mg limitation preconditions a smaller tomato root system, expectedly stimulating MGT transcription for Mg uptake or translocation.

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Faculty Opinions recommendation of Physcomitrella patens auxin-resistant mutants affect conserved elements of an auxin-signaling pathway.

Faculty Opinions – Post-Publication Peer Review of the Biomedical Literature ◽

10.3410/f.5704956.5686057 ◽

2010 ◽

Author(s):

Jiri Friml ◽

Steffen Vanneste

Keyword(s):

Signaling Pathway ◽

Physcomitrella Patens ◽

Auxin Signaling ◽

Auxin Signaling Pathway ◽

Resistant Mutants

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Silicon Effects on the Root System of Diverse Crop Species Using Root Phenotyping Technology

Plants ◽

10.3390/plants10050885 ◽

2021 ◽

Vol 10 (5) ◽

pp. 885

Author(s):

Pooja Tripathi ◽

Sangita Subedi ◽

Abdul Latif Khan ◽

Yong-Suk Chung ◽

Yoonha Kim

Keyword(s):

Root System ◽

Root Morphology ◽

Morphological Traits ◽

Crop Production ◽

Spatial Configuration ◽

Global Climate ◽

Learning Technologies ◽

Climate Change Scenarios ◽

Crop Species ◽

Wide Range

Roots play an essential function in the plant life cycle, as they utilize water and essential nutrients to promote growth and plant productivity. In particular, root morphology characteristics (such as length, diameter, hairs, and lateral growth) and the architecture of the root system (spatial configuration in soil, shape, and structure) are the key elements that ensure growth and a fine-tuned response to stressful conditions. Silicon (Si) is a ubiquitous element in soil, and it can affect a wide range of physiological processes occurring in the rhizosphere of various crop species. Studies have shown that Si significantly and positively enhances root morphological traits, including root length in rice, soybean, barley, sorghum, mustard, alfalfa, ginseng, and wheat. The analysis of these morphological traits using conventional methods is particularly challenging. Currently, image analysis methods based on advanced machine learning technologies allowed researchers to screen numerous samples at the same time considering multiple features, and to investigate root functions after the application of Si. These methods include root scanning, endoscopy, two-dimensional, and three-dimensional imaging, which can measure Si uptake, translocation and root morphological traits. Small variations in root morphology and architecture can reveal different positive impacts of Si on the root system of crops, with or without exposure to stressful environmental conditions. This review comprehensively illustrates the influences of Si on root morphology and root architecture in various crop species. Furthermore, it includes recommendations in regard to advanced methods and strategies to be employed to maintain sustainable plant growth rates and crop production in the currently predicted global climate change scenarios.

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Synergy between a shallow root system with a DRO1 homologue and localized P application improves P uptake of lowland rice

Scientific Reports ◽

10.1038/s41598-021-89129-z ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Aung Zaw Oo ◽

Yasuhiro Tsujimoto ◽

Mana Mukai ◽

Tomohiro Nishigaki ◽

Toshiyuki Takai ◽

...

Keyword(s):

Root System ◽

Crop Production ◽

Soil Surface ◽

P Uptake ◽

Ore Deposits ◽

Root Surface Area ◽

Genetic Traits ◽

P Use Efficiency ◽

Use Efficiency ◽

P Application

AbstractImproved phosphorus (P) use efficiency for crop production is needed, given the depletion of phosphorus ore deposits, and increasing ecological concerns about its excessive use. Root system architecture (RSA) is important in efficiently capturing immobile P in soils, while agronomically, localized P application near the roots is a potential approach to address this issue. However, the interaction between genetic traits of RSA and localized P application has been little understood. Near-isogenic lines (NILs) and their parent of rice (qsor1-NIL, Dro1-NIL, and IR64, with shallow, deep, and intermediate root growth angles (RGA), respectively) were grown in flooded pots after placing P near the roots at transplanting (P-dipping). The experiment identified that the P-dipping created an available P hotspot at the plant base of the soil surface layer where the qsor1-NIL had the greatest root biomass and root surface area despite no genotyipic differences in total values, whereby the qsor1-NIL had significantly greater biomass and P uptake than the other genotypes in the P-dipping. The superior surface root development of qsor1-NIL could have facilitated P uptakes from the P hotspot, implying that P-use efficiency in crop production can be further increased by combining genetic traits of RSA and localized P application.

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Evaluation of the Spatiotemporal Dynamics of Oxytetracycline and Its Control Effect Against Citrus Huanglongbing via Trunk Injection

Phytopathology ◽

10.1094/phyto-02-16-0114-r ◽

2016 ◽

Vol 106 (12) ◽

pp. 1495-1503 ◽

Cited By ~ 28

Author(s):

Jiahuai Hu ◽

Nian Wang

Keyword(s):

Root System ◽

Early Stage ◽

Spatiotemporal Dynamics ◽

Bacterial Disease ◽

In Planta ◽

Control Effect ◽

Chromatography Method ◽

Effective Measure ◽

Citrus Huanglongbing ◽

Trunk Injection

Citrus huanglongbing (HLB) or greening is a devastating bacterial disease that has destroyed millions of trees and is associated with phloem-residing ‘Candidatus Liberibacter asiaticus’ (Las) in Florida. In this study, we evaluated the spatiotemporal dynamics of oxytetracycline in planta and its control effect against HLB via trunk injection. Las-infected ‘Hamlin’ sweet orange trees on ‘Swingle’ citrumelo rootstock at the early stage of decline were treated with oxytetracycline hydrochloride (OTC) using trunk injection with varying number of injection ports. Spatiotemporal distribution of OTC and dynamics of Las populations were monitored by high-performance liquid chromatography method and qPCR assay, respectively. Uniform distribution of OTC throughout tree canopies and root system was achieved 2 days postinjection. High levels of OTC (>850 µg/kg) were maintained in leaf and root for at least 1 month and moderate OTC (>500 µg/kg) persisted for more than 9 months. Reduction of Las populations in root system and leaves of OTC-treated trees were over 95% and 99% (i.e., 1.76 and 2.19 log reduction) between 2 and 28 days postinjection. Conditions of trees receiving OTC treatment were improved, fruit yield was increased, and juice acidity was lowered than water-injected control even though their differences were not statistically significant during the test period. Our study demonstrated that trunk injection of OTC could be used as an effective measure for integrated management of citrus HLB.

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Emerging Viral Diseases of Tomato Crops

Molecular Plant-Microbe Interactions ◽

10.1094/mpmi-23-5-0539 ◽

2010 ◽

Vol 23 (5) ◽

pp. 539-548 ◽

Cited By ~ 161

Author(s):

Inge M. Hanssen ◽

Moshe Lapidot ◽

Bart P. H. J. Thomma

Keyword(s):

Crop Production ◽

Production Systems ◽

Genetic Resistance ◽

International Travel ◽

Viral Diseases ◽

Limiting Factor ◽

Emerging Viruses ◽

Plant Materials ◽

Tomato Production ◽

Climate Conditions

Viral diseases are an important limiting factor in many crop production systems. Because antiviral products are not available, control strategies rely on genetic resistance or hygienic measures to prevent viral diseases, or on eradication of diseased crops to control such diseases. Increasing international travel and trade of plant materials enhances the risk of introducing new viruses and their vectors into production systems. In addition, changing climate conditions can contribute to a successful spread of newly introduced viruses or their vectors and establishment of these organisms in areas that were previously unfavorable. Tomato is economically the most important vegetable crop worldwide and many viruses infecting tomato have been described, while new viral diseases keep emerging. Pepino mosaic virus is a rapidly emerging virus which has established itself as one of the most important viral diseases in tomato production worldwide over recent years. Begomovirus species and other whitefly-transmitted viruses are invading into new areas, and several recently described new viruses such as Tomato torrado virus and new Tospovirus species are rapidly spreading over large geographic areas. In this article, emerging viruses of tomato crops are discussed.

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Auxin requirements for a meristematic state in roots depend on a dual brassinosteroid function

10.1101/2020.11.24.395483 ◽

2020 ◽

Author(s):

M. Ackerman-Lavert ◽

Y. Fridman ◽

R Matosevich ◽

H Khandal ◽

L. Friedlander ◽

...

Keyword(s):

Signaling Pathways ◽

Auxin Biosynthesis ◽

Auxin Signaling ◽

Critical Ratio ◽

Dual Effect ◽

Normal Morphology ◽

Arabidopsis Root ◽

Auxin Synthesis ◽

Meristem Maintenance ◽

Transcriptional Output

SummaryThe organization of the root meristem is maintained by a complex interplay between plant hormones signaling pathways that both interpret and determine their accumulation and distribution. Brassinosteroids (BR) and auxin signaling pathways control the number of meristematic cells in the Arabidopsis root, via an interaction that appears to involve contradicting molecular outcomes, with BR promoting auxin signaling input but also repressing its output. However, whether this seemingly incoherent effect is significant for meristem function is unclear. Here, we established that a dual effect of BR on auxin, with BR simultaneously promoting auxin biosynthesis and repressing auxin transcriptional output, is essential for meristem maintenance. Blocking BR-induced auxin synthesis resulted in rapid BR-mediated meristem loss. Conversely, plants with reduced BR levels were resistant to loss of auxin biosynthesis and these meristems maintained their normal morphology despite a 10-fold decrease in auxin levels. In agreement, injured root meristems which rely solely on local auxin synthesis, regenerated when both auxin and BR synthesis were inhibited. Use of BIN2 as a tool to selectively inhibit BR signaling, revealed meristems with distinct phenotypes depending on the perturbed tissue; meristem reminiscent of BR-deficient mutants or of high BR exposure. This enabled mapping BR-auxin interactions to the outer epidermis and lateral root cap tissues, and demonstrated the essentiality of BR signaling in these tissues for meristem maintenance. BR activity in internal tissues however, proved necessary to control BR homeostasis. Together, we demonstrate a basis for inter-tissue coordination and how a critical ratio between these hormones determines the meristematic state.

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MicroRNAs Are Involved in Regulating Plant Development and Stress Response through Fine-Tuning of TIR1/AFB-Dependent Auxin Signaling

International Journal of Molecular Sciences ◽

10.3390/ijms23010510 ◽

2022 ◽

Vol 23 (1) ◽

pp. 510

Author(s):

Pan Luo ◽

Dongwei Di ◽

Lei Wu ◽

Jiangwei Yang ◽

Yufang Lu ◽

...

Keyword(s):

Stress Response ◽

Fine Tuning ◽

Auxin Signaling ◽

In Planta ◽

Auxin Response ◽

Signal Molecule ◽

Master Regulators ◽

Non Coding Rna ◽

Complex Regulation ◽

Indole 3 Acetic Acid

Auxin, primarily indole-3-acetic acid (IAA), is a versatile signal molecule that regulates many aspects of plant growth, development, and stress response. Recently, microRNAs (miRNAs), a type of short non-coding RNA, have emerged as master regulators of the auxin response pathways by affecting auxin homeostasis and perception in plants. The combination of these miRNAs and the autoregulation of the auxin signaling pathways, as well as the interaction with other hormones, creates a regulatory network that controls the level of auxin perception and signal transduction to maintain signaling homeostasis. In this review, we will detail the miRNAs involved in auxin signaling to illustrate its in planta complex regulation.

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Synergy Between a Shallow Root System With a DRO1 Homologue and Localized P Application Improves Rice P Uptake

10.21203/rs.3.rs-138072/v1 ◽

2021 ◽

Author(s):

Aung Zaw Oo ◽

YASUHIRO TSUJIMOTO ◽

Mana Mukai ◽

Tomohiro Nishigaki ◽

Toshiyuki Takai ◽

...

Keyword(s):

Root System ◽

Crop Production ◽

Soil Layer ◽

P Uptake ◽

Ore Deposits ◽

Root Surface Area ◽

Genetic Traits ◽

P Use Efficiency ◽

Use Efficiency ◽

P Application

Abstract Improved phosphorus (P) use efficiency for crop production is needed given the depleting phosphorus ore deposits and increasing ecological concerns about its excessive use. Root system architecture (RSA) is important in efficiently capturing immobile P in soils, while agronomically, localized P application near the roots is a potential approach to address this issue. However, the interaction between genetic traits of RSA and localized P application has been little understood. Near-isogenic lines (NILs) and their parent of rice (qsor1-NIL, Dro1-NIL, and IR64, with shallow, deep, and intermediate root growth angles (RGA), respectively) were grown in flooded pots after placing P near the roots at transplanting (P-dipping). The experiment identified that the P-dipping created an available P hotspot at the soil surface; the qsor1-NIL had the greatest root biomass and root surface area in the 0–3 cm soil layer despite no genotype differences in total values; the qsor1-NIL had significantly greater biomass and P uptake than the other genotypes in the P-dipping. The superior surface root development of qsor1-NIL could have facilitated P uptakes from the P hotspot, implying that P-use efficiency in crop production can be further increased by combining genetic traits of RSA and localized P application.

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Response of Chickpea (Cicer aritienum L.) to Sulphur and Zinc Nutrients Application and Rhizobium Inoculation in North Western Ethiopia

Turkish Journal of Agriculture - Food Science and Technology ◽

10.24925/turjaf.v8i10.2040-2048.3414 ◽

2020 ◽

Vol 8 (10) ◽

pp. 2040-2048

Author(s):

Beza Shewangizaw Woldearegay ◽

Anteneh Argaw ◽

Tesfaye Feyisa ◽

Birhan Abdulkadir ◽

Endalkachew Wold-Meskel

Keyword(s):

Crop Production ◽

Block Design ◽

P Uptake ◽

Sub Saharan Africa ◽

Limiting Factor ◽

Rhizobium Inoculation ◽

Combined Application ◽

Nodule Volume ◽

P Application ◽

Sub Saharan

In sub-Saharan Africa, multiple plant nutrients deficiency besides nitrogen (N) and phosphorus (P) is a major growth-limiting factor for crop production. As a result, some soils become non-responsive for Rhizobium inoculation besides P application. Based on the soil test result, the soil of Experimental sites had low organic matter (OM), nitrogen (N), phosphorus (P), sulphur (S) and zinc (Zn)[xy1]. Hence, an experiment was carried out on-farm at Gondar Zuria woreda in Tsion and Denzaz Kebeles to evaluate the effect of Rhizobium inoculation, S and Zn application on yield, nodulation, N and P uptake of chickpea. The experiment included twelve treatments developed via factorial combination of two level of inoculation (Rhizobium inoculated, un-inoculated), three level of S (0, 15, 30 kg Sulphur ha-1) and two levels of Zn (0, 1.5 kg Zinc ha-1). The treatment was laid out in randomized complete block design with three replications. Results showed that the highest mean nodule number (15.3) and nodule volume (1.3 ml plant-1) over locations were obtained with Rhizobium inoculation integrated with 15 kg S and 1.5 kg Zn ha-1 which resulted in 37.8% and 116.7% increment over the control check, respectively. It was also observed that combined application of Rhizobium and 30 kg S ha-1 caused the highest (6.7) mean nodulation rating and seed yield (1775.5 kg ha-1) over locations which resulted in 86.1% and 28 % increase over the control check, respectively. Moreover, this treatment improved P use efficiency of chickpea. On the bases of observed result, it can be concluded that the response of chickpea to Rhizobium and P application can be improved by S application and Rhizobium inoculation with application of 30 kg S ha-1 with recommended rate of P and starter N is recommended for chickpea production at the experimental locations in Gonder Zuria Woreda.

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