A MATE Transporter is Involved in Pathogenicity and IAA Homeostasis in the Hyperplastic Plant Pathogen Pseudomonas savastanoi pv. nerii

During the last years, many evidences have been accumulating about the phytohormone indole-3-acetic acid (IAA) as a multifaceted compound in the microbial world, with IAA playing a role as a bacterial intra and intercellular signaling molecule or as an effector during pathogenic or beneficial plant–bacteria interactions. However, pretty much nothing is known on the mechanisms that bacteria use to modulate IAA homeostasis, in particular on IAA active transport systems. Here, by an approach combining in silico three-dimensional (3D) structural modeling and docking, mutagenesis, quantitative gene expression analysis, and HPLC FLD auxin quantitative detection, for the first time a bacterial multidrug and toxic compound extrusion (MATE) transporter was demonstrated to be involved in the efflux of IAA, as well as of its conjugate IAA–Lysine, in the plant pathogenic hyperplastic bacterium Pseudomonas savastanoi pv. nerii strain Psn23. Furthermore, according to the role proved to be played by Psn23 MatE in the development of plant disease, and to the presence of Psn23 MatE homologs in all the genomospecies of the P. syringae complex, this membrane transporter could likely represent a promising target for the design of novel and selective anti-infective molecules for plant disease control.

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Precision agriculture and geospatial techniques for sustainable disease control

Indian Phytopathology ◽

10.1007/s42360-021-00334-2 ◽

2021 ◽

Author(s):

Daniel P. Roberts ◽

Nicholas M. Short ◽

James Sill ◽

Dilip K. Lakshman ◽

Xiaojia Hu ◽

...

Keyword(s):

Big Data ◽

Disease Control ◽

Crop Production ◽

Plant Disease ◽

Production Systems ◽

Cropping Systems ◽

Data Driven ◽

Agricultural Community ◽

Plant Disease Control ◽

Crop Germplasm

AbstractThe agricultural community is confronted with dual challenges; increasing production of nutritionally dense food and decreasing the impacts of these crop production systems on the land, water, and climate. Control of plant pathogens will figure prominently in meeting these challenges as plant diseases cause significant yield and economic losses to crops responsible for feeding a large portion of the world population. New approaches and technologies to enhance sustainability of crop production systems and, importantly, plant disease control need to be developed and adopted. By leveraging advanced geoinformatic techniques, advances in computing and sensing infrastructure (e.g., cloud-based, big data-driven applications) will aid in the monitoring and management of pesticides and biologicals, such as cover crops and beneficial microbes, to reduce the impact of plant disease control and cropping systems on the environment. This includes geospatial tools being developed to aid the farmer in managing cropping system and disease management strategies that are more sustainable but increasingly complex. Geoinformatics and cloud-based, big data-driven applications are also being enlisted to speed up crop germplasm improvement; crop germplasm that has enhanced tolerance to pathogens and abiotic stress and is in tune with different cropping systems and environmental conditions is needed. Finally, advanced geoinformatic techniques and advances in computing infrastructure allow a more collaborative framework amongst scientists, policymakers, and the agricultural community to speed the development, transfer, and adoption of these sustainable technologies.

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Plant Disease Control Efficacy of Platycladus orientalis and Its Antifungal Compounds

Plants ◽

10.3390/plants10081496 ◽

2021 ◽

Vol 10 (8) ◽

pp. 1496

Author(s):

Sohyun Bae ◽

Jae Woo Han ◽

Quang Le Dang ◽

Hun Kim ◽

Gyung Ja Choi

Keyword(s):

Disease Control ◽

Rice Blast ◽

Plant Disease ◽

Methanol Extract ◽

Crop Protection ◽

Ethyl Acetate Fraction ◽

Antifungal Compounds ◽

Control Efficacy ◽

Platycladus Orientalis ◽

Plant Disease Control

Plants contain a number of bioactive compounds that exhibit antimicrobial activity, which can be recognized as an important source of agrochemicals for plant disease control. In searching for natural alternatives to synthetic fungicides, we found that a methanol extract of the plant species Platycladus orientalis suppressed the disease development of rice blast caused by Magnaporthe oryzae. Through a series of chromatography procedures in combination with activity-guided fractionation, we isolated and identified a total of eleven compounds including four labdane-type diterpenes (1–4), six isopimarane-type diterpenes (5–10), and one sesquiterpene (11). Of the identified compounds, the MIC values of compounds 1, 2, 5 & 6 mixture, 9, and 11 ranged from 100 to 200 μg/mL against M. oryzae, whereas the other compounds were over 200 μg/mL. When rice plants were treated with the antifungal compounds, compounds 1, 2, and 9 effectively suppressed the development of rice blast at all concentrations tested by over 75% compared to the non-treatment control. In addition, a mixture of compounds 5 & 6 that constituted 66% of the P. orientalis ethyl acetate fraction also exhibited a moderate disease control efficacy. Together, our data suggest that the methanol extract of P. orientalis including terpenoid compounds has potential as a crop protection agent.

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Review of Plant disease control, principles and practice, by Maloy OC. 1993; Photosynthesis: molecular, physiological and environmental processes, by Lawlor DW. 1993 and Plant mitochondria, by Brennicke A, Kuck U. 1993.

Annals of Botany ◽

10.1006/anbo.1994.1057 ◽

1994 ◽

Vol 73 (4) ◽

pp. 461-464

Author(s):

D Parry

Keyword(s):

Disease Control ◽

Plant Disease ◽

Plant Mitochondria ◽

Environmental Processes ◽

Plant Disease Control

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Quantitative Determination of Cd in Soil Using Laser-Induced Breakdown Spectroscopy in Air and Ar Conditions

Molecules ◽

10.3390/molecules23102492 ◽

2018 ◽

Vol 23 (10) ◽

pp. 2492 ◽

Cited By ~ 8

Author(s):

Xiaodan Liu ◽

Fei Liu ◽

Weihao Huang ◽

Jiyu Peng ◽

Tingting Shen ◽

...

Keyword(s):

Heavy Metal ◽

Least Squares ◽

Three Dimensional ◽

Accurate Method ◽

Laser Induced Breakdown Spectroscopy ◽

Quantitative Detection ◽

Support Vector ◽

Least Squares Regression ◽

Breakdown Spectroscopy ◽

Laser Induced Breakdown

Rapid detection of Cd content in soil is beneficial to the prevention of soil heavy metal pollution. In this study, we aimed at exploring the rapid quantitative detection ability of laser- induced breakdown spectroscopy (LIBS) under the conditions of air and Ar for Cd in soil, and finding a fast and accurate method for quantitative detection of heavy metal elements in soil. Spectral intensity of Cd and system performance under air and Ar conditions were analyzed and compared. The univariate model and multivariate models of partial least-squares regression (PLSR) and least-squares support vector machine (LS-SVM) of Cd under the air and Ar conditions were built, and the LS-SVM model under the Ar condition obtained the best performance. In addition, the principle of influence of Ar on LIBS detection was investigated by analyzing the three-dimensional profile of the ablation crater. The overall results indicated that LIBS combined with LS-SVM under the Ar condition could be a useful tool for the accurate quantitative detection of Cd in soil and could provide reference for environmental monitoring.

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Biodynamics of supine humans and interaction with transport systems during vibration and shocks

Journal of Low Frequency Noise Vibration and Active Control ◽

10.1177/1461348417725957 ◽

2017 ◽

Vol 38 (2) ◽

pp. 808-816 ◽

Cited By ~ 1

Author(s):

Salam Rahmatalla ◽

Jonathan DeShaw ◽

Khalid Barazanji

Keyword(s):

Relative Motion ◽

Random Vibration ◽

Whole Body Vibration ◽

Three Dimensional ◽

Whole Body ◽

Transport Systems ◽

Biomechanical Response ◽

Contact Surfaces ◽

Vertical Accelerations ◽

Human Transport

This work investigates the effect of the contact surfaces on the biomechanical response of supine humans during whole-body vibration and shocks. Twelve participants were exposed to three-dimensional random vibration and shocks and were tested with two types of contact surfaces: (i) litter only, and (ii) litter with spinal board. The two configurations were tested with and without body straps to secure the supine human. The addition of the spinal board reduced the involuntary motion of the supine humans in most directions. There were significant reductions in the relative vertical accelerations at the neck and torso areas, especially during shocks ( p < 0.01). The inclusion of body straps with the spinal board was more effective in reducing the relative motion in most directions when shocks were presented. This study shows that the ergonomic design of the human transport system and the underlying contacting surfaces should be studied during dynamic transport environments.

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