Interactions Between Bacillus Spp., Pseudomonas Spp. and Cannabis sativa Promote Plant Growth

Plant growth-promoting rhizobacteria (PGPR) deploy several mechanisms to improve plant health, growth and yield. The aim of this study was to evaluate the efficacy of two Pseudomonas spp. strains and three Bacillus spp. strains used as single treatments and in consortia to improve the yield of Cannabis sativa and characterize the impact of these treatments on the diversity, structure and functions of the rhizosphere microbiome. Herein, we demonstrate a significant C. sativa yield increase up to 70% when inoculated with three different Pseudomonas spp./Bacillus spp. consortia but not with single inoculation treatments. This growth-promoting effect was observed in two different commercial soil substrates commonly used to grow cannabis: Promix and Canna coco. Marker-based genomic analysis highlighted Bacillus spp. as the main modulator of the rhizosphere microbiome diversity and Pseudomonas spp. as being strongly associated with plant growth promotion. We describe an increase abundance of predicted PGPR metabolic pathways linked with growth-promoting interactions in C. sativa.

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Isolation and identification of plant growth promoting rhizobacteria from maize (Zea mays L.) rhizosphere and their plant growth promoting effect on rice (Oryza sativa L.)

Journal of Plant Protection Research ◽

10.1515/jppr-2017-0020 ◽

2017 ◽

Vol 57 (2) ◽

pp. 144-151 ◽

Cited By ~ 12

Author(s):

Arun Karnwal

Keyword(s):

Zea Mays ◽

Plant Growth ◽

Growth Promotion ◽

Oryza Sativa L ◽

Plant Growth Promoting Rhizobacteria ◽

Promoting Effect ◽

Isolation And Identification ◽

Plant Growth Promoting ◽

Growth Promoting

AbstractThe use of plant growth promoting rhizobacteria is increasing in agriculture and gives an appealing manner to replace chemical fertilizers, pesticides, and dietary supplements. The objective of our research was to access the plant growth promotion traits ofPseudomonas aeruginosa,P. fluorescensandBacillus subtilisisolated from the maize (Zea maysL.) rhizosphere.In vitrostudies showed that isolates have the potential to produce indole acetic acid (IAA), hydrogen cyanide, phosphate solubilisation, and siderophore. RNA analysis revealed that two isolates were 97% identical toP. aeruginosastrain DSM 50071 andP. aeruginosastrain NBRC 12689 (AK20 and AK31), while two others were 98% identical toP. fluorescensstrain ATCC 13525,P. fluorescensstrain IAM 12022 (AK18 and AK45) and one other was 99% identical toB. subtilisstrain NCDO 1769 (AK38). Our gnotobiotic study showed significant differences in plant growth variables under control and inoculated conditions. In the present research, it was observed that the isolated strains had good plant growth promoting effects on rice.

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Seed treatment with chitosan synergizes plant growth promoting ability ofPseudomonas aeruginosa-P17 in sorghum (Sorhum bicolorL.)

10.1101/601328 ◽

2019 ◽

Author(s):

G. Praveen Kumar ◽

Suseelendra Desai ◽

Bruno M. Moerschbacher ◽

Nour Eddine-El Gueddari

Keyword(s):

Plant Growth ◽

Plant Growth Promotion ◽

Growth Promotion ◽

Abiotic Stress Tolerance ◽

Growth And Yield ◽

Systemic Resistance ◽

Bacterial Strains ◽

Promoting Effect ◽

Plant Growth Promoting ◽

Growth Promoting

AbstractInoculation of crop plants with PGPR has in a large number of investigations resulted in increased plant growth and yield both in the greenhouse and in the field. This plant growth promoting effect of bacteria could be due to net result of synergistic effect of various pgpr traits that they exert in the rhizosphere region of the plant. Four (04) bacterial strain of fluorescent Pseudomonas spp. viz. P1, P17, P22 and P28 were identified previously for their plant growth promoting nature and abiotic stress tolerance and selected further to assess their chitinolytic activity and growth promotion on sorghum in combination with chitosans of low and high degree of acetylation. It was found that P1 has no chitin degrading nature and rest of the three strains have this property. When studied for their ability to grow in presence of chitosans of DA 1.6, 11, 35 and 56% all the strains showed growth in presence of chitosans. Seed bacterization of sorghum seeds with 04 bacterial strains in the presence and absence of chitosans (both low and high DA) and assessment of plant growth promotion after 15 days of sowing showed that P17+DA 56% chitosan combination showed higher growth of seedlings in plant growth chamber with highest root length of 25.9 cm, highest shoot length of 32.1 cm and dry mass of 132.7 mg/ plant. In P17+DA 56% chitosan treated seedlings various defence enzymes and PR-proteins were found to be present in highest quantities as compared to P1 and un-inoculated controls. Since this strain showed highest growth promotion of sorghum seedlings chitin-chitosan modifying enzyme (CCME) of this strain was partially characterized using different proteomic tools and techniques. CCME of P17 had one active polypeptide with a Pi in the range of 3.0-4.0. The digestion pattern of acetylated and deacetylated chitosans showed that P17 enzyme has endochitinase activity. Substrate specificity assay showed that the enzyme had more specificity towards highly acetylated chitosans. Two dimensional PAGE and MS analysis of the protein revealed similarities of this enzyme with protein of Pseudomonas aeruginosa chitinase PA01 strain of GenBank. In conclusion, the study established the option of opening new possibilities for developing bacterial-chitosan (P17+DA 56% chitosan) product for plant growth promotion and induced systemic resistance in sorghum.

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Identification of Plant Growth Promoting Rhizobacteria That Improve the Performance of Greenhouse-Grown Petunias under Low Fertility Conditions

Plants ◽

10.3390/plants10071410 ◽

2021 ◽

Vol 10 (7) ◽

pp. 1410

Author(s):

Kaylee A. South ◽

Nathan P. Nordstedt ◽

Michelle L. Jones

Keyword(s):

Plant Growth ◽

Growth Promotion ◽

Genomic Analysis ◽

Dry Weight ◽

Plant Growth Promoting Rhizobacteria ◽

Low Fertility ◽

Plant Performance ◽

Flower Bud ◽

Plant Growth Promoting ◽

Growth Promoting

The production of greenhouse ornamentals relies on high fertilizer inputs to meet scheduling deadlines and quality standards, but overfertilization has negative environmental impacts. The goals of this study were to identify plant-growth-promoting rhizobacteria (PGPR) that can improve greenhouse ornamental crop performance with reduced fertilizer inputs, and to identify the best measurements of plant performance for assessing the beneficial impact of PGPR on ornamentals. A high-throughput greenhouse trial was used to identify 14 PGPR isolates that improved the flower/bud number and shoot dry weight of Petunia × hybrida ‘Picobella Blue’ grown under low fertility conditions in peat-based media. These 14 PGPR were then applied to petunias grown under low fertility conditions (25 mg L−1 N). PGPR-treated plants were compared to negative (untreated at 25 mg L−1 N) and positive (untreated at 50, 75, 100, and 150 mg L−1 N) controls. Multiple parameters were measured in the categories of flowering, vegetative growth, and vegetative quality to determine the best measurements to assess improvements in ornamental plant performance. Caballeronia zhejiangensis C7B12-treated plants performed better in almost all parameters and were comparable to untreated plants fertilized with 50 mg L−1 N. Genomic analysis identified genes that were potentially involved in plant growth promotion. Our study identified potential PGPR that can be used as biostimulants to produce high-quality greenhouse ornamentals with lower fertilizer inputs.

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Plant Growth-Promoting Rhizobacteria as a Green Alternative for Sustainable Agriculture

Sustainability ◽

10.3390/su131910986 ◽

2021 ◽

Vol 13 (19) ◽

pp. 10986

Author(s):

Hema Chandran ◽

Mukesh Meena ◽

Prashant Swapnil

Keyword(s):

Plant Growth ◽

Sustainable Agriculture ◽

Growth Promotion ◽

Plant Growth Promoting Rhizobacteria ◽

Antioxidant Systems ◽

Cell Organelles ◽

Positive Interaction ◽

Plant Growth Promoting ◽

Growth Promoting ◽

The Impact

Environmental stress is a major challenge for sustainable food production as it reduces yield by generating reactive oxygen species (ROS) which pose a threat to cell organelles and biomolecules such as proteins, DNA, enzymes, and others, leading to apoptosis. Plant growth-promoting rhizobacteria (PGPR) offers an eco-friendly and green alternative to synthetic agrochemicals and conventional agricultural practices in accomplishing sustainable agriculture by boosting growth and stress tolerance in plants. PGPR inhabit the rhizosphere of soil and exhibit positive interaction with plant roots. These organisms render multifaceted benefits to plants by several mechanisms such as the release of phytohormones, nitrogen fixation, solubilization of mineral phosphates, siderophore production for iron sequestration, protection against various pathogens, and stress. PGPR has the potential to curb the adverse effects of various stresses such as salinity, drought, heavy metals, floods, and other stresses on plants by inducing the production of antioxidant enzymes such as catalase, peroxidase, and superoxide dismutase. Genetically engineered PGPR strains play significant roles to alleviate the abiotic stress to improve crop productivity. Thus, the present review will focus on the impact of PGPR on stress resistance, plant growth promotion, and induction of antioxidant systems in plants.

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Plant growth promoting rhizobacteria improve growth and yield related attributes of chili under low nitrogen availability

PLoS ONE ◽

10.1371/journal.pone.0261468 ◽

2021 ◽

Vol 16 (12) ◽

pp. e0261468

Author(s):

Ali Raza ◽

Shaghef Ejaz ◽

Muhammad Shahzad Saleem ◽

Vaclav Hejnak ◽

Furqan Ahmad ◽

...

Keyword(s):

Plant Growth ◽

Management Practices ◽

Growth Traits ◽

Plant Growth Promoting Rhizobacteria ◽

Crop Plants ◽

Growth And Yield ◽

Control Treatment ◽

Plant Growth Promoting ◽

Growth Promoting ◽

The Impact

Nitrogen (N) is a macronutrient desired by crop plants in large quantities. However, hiking fertilizer prices need alternative N sources for reducing its requirements through appropriate management practices. Plant growth promoting rhizobacteria (PGPR) are well-known for their role in lowering N requirements of crop plants. This study assessed the impact of PGPR inoculation on growth, allometry and biochemical traits of chili under different N doses. Two PGPR, i.e., Azospirillum ‘Er-20’ (nitrogen fixing) and Agrobacterium ‘Ca-18’ (phosphorous solubilizing) were used for inoculation, while control treatment had no PGPR inoculation. Six N doses, i.e., 100, 80, 75, 70, 60 and 50% of the N required by chili were included in the study. Data relating to growth traits, biochemical attributes and yield related traits were recorded. Interaction among N doses and PGPR inoculation significantly altered all growth traits, biochemical attributes and yield related traits. The highest values of the recorded traits were observed for 100% N with and without PGPR inoculation and 75% N with PGPR inoculation. The lowest values of the recorded traits were noted for 50% N without PGPR inoculation. The PGPR inoculation improved the measured traits compared to the traits recorded noted in same N dose without PGPR inoculation. Results revealed that PGPR had the potential to lower 25% N requirement for chili. Therefore, it is recommended that PGPR must be used in chili cultivation to lower N requirements.

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