Identification of the effectiveness of associative rhizobacteria in spring wheat cultivation

Received: January 31st, 2021 ; Accepted: October 5th, 2021 ; Published: October 19th, 2021 ; Correspondence: [email protected] maximum increase in wheat yield (by 67% to the control), associated with a decrease in the root rot development by 19%, an increase in the productive bushiness by 18%, the spike weight by 26%, in the grains number per spike by 8% was noted when using the Bacillus subtilis strain 124-11; the strain effect on leaf diseases was insignificant (2–5%). The plants differed in the maximum changes (to control) in the total bushiness by 59%, the plants vegetative part weight by 27%, the flag leaf area by 21%, the pre-flag leaf area by 28%, the roots numbers and weight by 20% and 62%. After plants treatments with the Pseudomonas fluorescens strain SPB2137, the wheat maturation period was reduced by 9% (to the control), wheat yield increased by 58% due to a decrease in the development of root rot and septoria by 18%, the yellow rust pustules area by 44%; the productive bushiness and plant height increased by 25% and 19%, the plant vegetative weight by 21%, the spike length by 4%. The most expressed protective and growth-stimulating effect was shown by the Sphingomonas sp. K1B, which caused a maximum decrease (to the control) in the root rot and yellow rust development by 22% and 7%, the strips length by 22%, the pustules number in the strip by 29%, brown rust by 10%, septoria by 11%. Wheat plants were characterized by a large number and length of roots by 17% and 13%, root weight by 49%, a maximum increase in the nodal roots number and length by 15% and 17%; total bushiness by 34.5%; a maximum increase in plant vegetative weight by 37%; the spike length by 3%

Microbial inoculum development for ameliorating crop drought stress:A case study of Variovorax paradoxus 5C-2

Drought affects plant hormonal homeostasis, including root to shoot signalling. The plant is intimately connected below-ground with soil-dwelling microbes, including plant growth promoting rhizobacteria (PGPR) that can modulate plant hormonal homeostasis. Incorporating PGPR into the rhizosphere often delivers favourable results in greenhouse experiments, while field applications are much less predictable. We review the natural processes that affect the formation and dynamics of the rhizosphere, establishing a model for successful field application of PGPR utilizing an example microbial inoculum, Variovorax paradoxus 5C-2

Modulation of tomato root architecture and root hair traits by Pseudomonas brassicacearum and Variovorax paradoxus containing 1-aminocyclopropane-1-carboxylate deaminase

By decreasing root 1-aminocyclopropane-1-carboxylate (ACC) content and plant ethylene production, the microbial enzyme ACC deaminase is a widespread beneficial trait of plant growth-promoting rhizobacteria (PGPR), ameliorating ethylene-mediated root growth inhibition. However, relatively little is known about whether bacterial ACC deaminase modulates root architecture and root hair traits. Thus the dwarf tomato (Solanum lycopersicum) cultivar Micro-Tom was inoculated in vitro with Pseudomonas brassicacearum Am3, its ACC deaminase deficient mutant T8-1, a known PGPR strain Variovorax paradoxus 5C-2 or chemically treated with agents that promoted or inhibited ethylene production or sensitivity (Ag+, Co2+, and ACC). ACC treatment reduced both root elongation and the number of lateral roots, while ethylene inhibitors (Ag+, Co2+) and V. paradoxus 5C-2 promoted primary root elongation, but differentially affected lateral root length and number. Ag+ stimulated lateral root development, while Co2+ and V. paradoxus 5C-2 did not. Inoculation with P. brassicacearum Am3 and T8-1 inhibited elongation of the primary and lateral roots at a high inoculum concentration (106 cells cm3). All bacterial strains significantly increased the length and number of root hairs, with these effects more pronounced in P. brassicacearum Am3 than in the mutant T8-1. Treatment with Ag+ inhibited root hair formation and elongation, while Co2+ had the opposite effects. ACC treatment had no effect on root hair elongation but increased root hair density. While root growth inhibition caused by P. brassicacearum Am3 was independent of ACC deaminase, the promotion of root hair elongation and density by this strain was augmented by ACC deaminase activity. Thus ACC deaminase can modulate the morphological impacts of bacteria on root hair response by affecting plant ethylene content. © 2022, Institute of Experimental Botany, ASCR. All rights reserved

Dataset for transcriptome analysis of abscisic acid degrading bacterium Novosphingobium sp. P6W

© 2019 The Author(s) Plant growth-promoting rhizobacteria (PGPR) improve plant productivity and stress resistance. The mechanisms involved in plant-microbe interactions include the modulation of plant hormone status. The Novosphingobium sp. strain P6W was previously described as the bacterium capable of abscisic acid (ABA) degradation, and its inoculation decreased ABA concentrations in planta. The metabolic pathway for the ABA degradation in bacteria is still unknown. Here we present transcriptome data of Novosphingobium sp. P6W grown in the medium supplemented with ABA or fructose as the carbon source. Cleaned FASTQ files for the RNA-seq libraries are deposited in the NCBI Sequence Read Archive (SRA, Identifier: SRP189498) and have been assigned BioProject accession PRJNA529223

Cadmium accumulation and buffering of cadmium-induced stress by arbuscular mycorrhiza in three Pisum sativum L. genotypes

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Genetic variability in tolerance to cadmium and accumulation of heavy metals in pea (Pisum sativum L.)

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Comparative Study of the Abscisic Acid Metabolism Using Analogue Tritium-Labeled in the Cyclohexene or Side Moiety

© 2020, Pleiades Publishing, Ltd. Abstract: A procedure was developed for introducing tritium into the side chain of the abscisic acid (ABA) molecule. The reaction was carried out in dioxane in the presence of the Lindlar catalyst. The yield of the labeled product was 70% and the molar radioactivity was 44 Ci/mol. The tritium-labeled abscisic acid analogue was found to be a growth substrate for soil bacteria that incorporate a radioactive label into cellular metabolites. The absorption of the label by bacteria from the side chain of abscisic acid is more than an order of magnitude higher than that for labeling in the cyclohexene moiety. The results indicate the existence of a previously unknown metabolism pathway of ABA in microorganisms

Rhizosphere bacterium rhodococcus sp. P1y metabolizes ab-scisic acid to form dehydrovomifoliol

The phytohormone abscisic acid (ABA) plays an important role in plant growth and in response to abiotic stress factors. At the same time, its accumulation in soil can negatively affect seed germination, inhibit root growth and increase plant sensitivity to pathogens. ABA is an inert compound resistant to spontaneous hydrolysis and its biological transformation is scarcely under-stood. Recently, the strain Rhodococcus sp. P1Y was described as a rhizosphere bacterium assimilat-ing ABA as a sole carbon source in batch culture and affecting ABA concentrations in plant roots. In this work, the intermediate product of ABA decomposition by this bacterium was isolated and purified by preparative HPLC techniques. Proof that this compound belongs to ABA derivatives was carried out by measuring the molar radioactivity of the conversion products of this phytohor-mone labeled with tritium. The chemical structure of this compound was determined by instrumen-tal techniques including high-resolution mass spectrometry, NMR spectrometry, FTIR and UV spec-troscopies. As a result, the metabolite was identified as (4RS)-4-hydroxy-3,5,5-trimethyl-4-[(E)-3-oxobut-1-enyl]cyclohex-2-en-1-one (dehydrovomifoliol). Based on the data obtained, it was con-cluded that the pathway of bacterial degradation and assimilation of ABA begins with a gradual shortening of the acyl part of the molecule