Growth promotion of pineapple 'vitória' by humic acids and burkholderia spp. during acclimatization

In vitro propagation of pineapple produces uniform and disease-free plantlets, but requires a long period of acclimatization before transplanting to the field. Quicker adaptation to the ex vitro environment and growth acceleration of pineapple plantlets are prerequisites for the production of a greater amount of vigorous, well-rooted planting material. The combination of humic acids and endophytic bacteria could be a useful technological approach to reduce the critical period of acclimatization. The aim of this study was to evaluate the initial performance of tissue-cultured pineapple variety Vitória in response to application of humic acids isolated from vermicompost and plant growth-promoting bacteria (Burkholderia spp.) during greenhouse acclimatization. The basal leaf axils were treated with humic acids while roots were immersed in bacterial medium. Humic acids and bacteria application improved shoot growth (14 and 102 %, respectively), compared with the control; the effect of the combined treatment was most pronounced (147 %). Likewise, humic acids increased root growth by 50 %, bacteria by 81 % and the combined treatment by 105 %. Inoculation was found to significantly increase the accumulation of N (115 %), P (112 %) and K (69 %) in pineapple leaves. Pineapple growth was influenced by inoculation with Burkholderia spp., and further improved in combination with humic acids, resulting in higher shoot and root biomass as well as nutrient contents (N 132 %, P 131 %, K 80 %) than in uninoculated plantlets. The stability and increased consistency of the host plant response to bacterization in the presence of humic substances indicate a promising biotechnological tool to improve growth and adaptation of pineapple plantlets to the ex vitro environment.

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Genome-guided insights of tropical Bacillus strains efficient in maize growth promotion

FEMS Microbiology Ecology ◽

10.1093/femsec/fiaa157 ◽

2020 ◽

Vol 96 (9) ◽

Author(s):

Camila Cristina Vieira Velloso ◽

Christiane Abreu de Oliveira ◽

Eliane Aparecida Gomes ◽

Ubiraci Gomes de Paula Lana ◽

Chainheny Gomes de Carvalho ◽

...

Keyword(s):

Plant Growth ◽

Growth Promotion ◽

Dry Weight ◽

Phenotypic Characterization ◽

Plant Growth Promoting Bacteria ◽

Maize Genotypes ◽

Plant Growth Promoting ◽

Growth Promoting ◽

Bacillus Strains

ABSTRACT Plant growth promoting bacteria (PGPB) are an efficient and sustainable alternative to mitigate biotic and abiotic stresses in maize. This work aimed to sequence the genome of two Bacillus strains (B116 and B119) and to evaluate their plant growth-promoting (PGP) potential in vitro and their capacity to trigger specific responses in different maize genotypes. Analysis of the genomic sequences revealed the presence of genes related to PGP activities. Both strains were able to produce biofilm and exopolysaccharides, and solubilize phosphate. The strain B119 produced higher amounts of IAA-like molecules and phytase, whereas B116 was capable to produce more acid phosphatase. Maize seedlings inoculated with either strains were submitted to polyethylene glycol-induced osmotic stress and showed an increase of thicker roots, which resulted in a higher root dry weight. The inoculation also increased the total dry weight and modified the root morphology of 16 out of 21 maize genotypes, indicating that the bacteria triggered specific responses depending on plant genotype background. Maize root remodeling was related to growth promotion mechanisms found in genomic prediction and confirmed by in vitro analysis. Overall, the genomic and phenotypic characterization brought new insights to the mechanisms of PGP in tropical Bacillus.

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Seed-Biopriming of Durum Wheat with Diazotrophic Plant Growth Promoting Bacteria (PGPB) Enhanced Tolerance to Fusarium Head Blight (FHB) and Salinity Stress

10.21203/rs.2.16636/v2 ◽

2019 ◽

Author(s):

Adel Hadj Brahim ◽

Mouna Jlidi ◽

Lobna Daoud ◽

Manel Ben-Ali ◽

Asmahen Akremi ◽

...

Keyword(s):

Plant Growth ◽

Durum Wheat ◽

Abiotic Stresses ◽

Growth Promotion ◽

Plant Growth Promoting Bacteria ◽

Head Blight ◽

Biotic And Abiotic Stresses ◽

Plant Growth Promoting ◽

Growth Promoting

Abstract Background There is growing interest in the use of bioinoculants based on plant growth promoting bacteria (PGPB) to promote plant growth under biotic and abiotic stresses. To our knowledge much work has not been, thus far, done on seedbiopriming of durum wheat for tolerance to biotic and abiotic stresses. In the present work, we report detailed account of the effectiveness a potent bacterial strain with proven plant growth-promoting ability and antimicrobial activity. The isolate was selected following screening of several bacterial strains isolated from halophytes that grow in a coastal saline soil in Tunisia for their role in enhancing durum wheat tolerance to both salinity stress and head blight disease. Results Accordingly, Bacillus strains MA9, MA14, MA17 and MA19 were found to have PGPB characteristics as they produced indole-3-acetic acid, siderophores and lytic enzymes, fixed free atmospheric nitrogen, and solubilized inorganic phosphate, in vitro. The in vivo study that involved in planta inoculation assays under control (25 mM NaCl) and stress (125 mM NaCl) conditions indicated that all PGPB strains significantly (P < 0.05) increased the total plant length, dry weight, root area, seed weight, nitrogen, protein and total mineral content. On the other hand, strain MA17 reduced Fusarium Head Blight (FHB) disease incidence in wheat explants by 64.5%, showing that the strain has antifungal activity as was also displayed by in vitro inhibition study. Conclusions Both in vitro and in vivo studies showed that MA9, MA14 MA9, MA14, MA17 and MA19 strains were able to play the PGPB role. Yet, biopriming with Bacillus strain MA17 offered the highest bioprotection against FHB, plant growth promotion, and salinity tolerance. Hence, the MA17 strain should further be evaluated under field condition and formulated for commercial production. Besides, the strain could further be evaluated for its potential role in bioprotection and growth promotion of other crop plants. We believe, the strain has potential to significantly contribute to wheat production in the arid and semi-arid region, especially the salt affected Middle Eastern Region, besides its potential role in improving wheat production under biotic and abiotic stresses in other parts of the world.

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Genome-Wide Transcriptome Analysis of Rice Seedlings after Seed Dressing with Paenibacillus yonginensis DCY84T and Silicon

International Journal of Molecular Sciences ◽

10.3390/ijms20235883 ◽

2019 ◽

Vol 20 (23) ◽

pp. 5883 ◽

Cited By ~ 1

Author(s):

Yo-Han Yoo ◽

Minjae Kim ◽

Anil Kumar Nalini Chandran ◽

Woo-Jong Hong ◽

Hye Ryun Ahn ◽

...

Keyword(s):

Plant Growth ◽

Transcriptome Analysis ◽

Growth Promotion ◽

Combined Treatment ◽

Interaction Network ◽

Plant Growth Promoting Bacteria ◽

Protein Protein Interaction ◽

Plant Growth Promoting ◽

Abundant Element ◽

Upregulated Genes

Plant-growth-promoting bacteria (PGPB) are beneficial microorganisms that can also protect against disease and environmental stress. Silicon (Si) is the second most abundant element in soil, and is known to increase plant growth, grain yield, resistance to biotic stress, and tolerance to abiotic stress. Combined treatment of PGPB and Si has been shown to further enhance plant growth and crop yield. To determine the global effects of the PGPB and Si on rice growth, we compared rice plants treated with Paenibacillus yonginensis DCY84T (DCY84T) and Si with untreated rice. To identify the genes that respond to DCY84T+Si treatment in rice, we performed an RNA-Seq transcriptome analysis by sampling treated and untreated roots on a weekly basis for three weeks. Overall, 576 genes were upregulated, and 394 genes were downregulated in treated roots, using threshold fold-changes of at least 2 (log2) and p-values < 0.05. Gene ontology analysis showed that phenylpropanoids and the L-phenylalanine metabolic process were prominent in the upregulated genes. In a metabolic overview analysis using the MapMan toolkit, pathways involving phenylpropanoids and ethylene were strongly associated with upregulated genes. The functions of seven upregulated genes were identified as being associated with drought stress through a literature search, and a stress experiment confirmed that plants treated with DCY84T+Si exhibited greater drought tolerance than the untreated control plants. Furthermore, the predicted protein–protein interaction network analysis associated with DCY84T+ Si suggests mechanisms underlying growth promotion and stress tolerance.

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Effect of the endophytic plant growth promoting Enterobacter ludwigii EB4B on tomato growth

Hellenic Plant Protection Journal ◽

10.2478/hppj-2020-0006 ◽

2020 ◽

Vol 13 (2) ◽

pp. 54-65 ◽

Cited By ~ 1

Author(s):

M.E.A. Bendaha ◽

H.A. Belaouni

Keyword(s):

Root Length ◽

Biocontrol Agent ◽

Growth Promotion ◽

Dry Weight ◽

Antagonistic Activity ◽

Rrna Gene ◽

Plant Growth Promoting ◽

Enterobacter Ludwigii ◽

Tomato Growth

SummaryThis study aims to develop a biocontrol agent against Fusarium oxysporum f.sp. radicis-lycopersici (FORL) in tomato. For this, a set of 23 bacterial endophytic isolates has been screened for their ability to inhibit in vitro the growth of FORL using the dual plate assay. Three isolates with the most sound antagonistic activity to FORL have been qualitatively screened for siderophore production, phosphates solubilization and indolic acetic acid (IAA) synthesis as growth promotion traits. Antagonistic values of the three candidates against FORL were respectively: 51.51 % (EB4B), 51.18 % (EB22K) and 41.40 % (EB2A). Based on 16S rRNA gene sequence analysis, the isolates EB4B and EB22K were closely related to Enterobacter ludwigii EN-119, while the strain EB2A has been assigned to Leclercia adecarboxylata NBRC 102595. The promotion of tomato growth has been assessed in vitro using the strains EB2A, EB4B and EB22K in presence of the phytopathogen FORL. The treatments with the selected isolates increased significantly the root length and dry weight. Best results were observed in isolate EB4B in terms of growth promotion in the absence of FORL, improving 326.60 % of the root length and 142.70 % of plant dry weight if compared with untreated controls. In the presence of FORL, the strain EB4B improved both root length (180.81 %) and plant dry weight (202.15 %). These results encourage further characterization of the observed beneficial effect of Enterobacter sp. EB4B for a possible use as biofertilizer and biocontrol agent against FORL.

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Isolation and Characterization of Salt Tolerant Endophytic and Rhizospheric Plant Growth-Promoting Bacteria (PGPB) Associated with the Halophyte Plant (Sesuvium Verrucosum) Grown in KSA

International Journal of Applied Sciences and Biotechnology ◽

10.3126/ijasbt.v3i3.13440 ◽

2015 ◽

Vol 3 (3) ◽

pp. 552-560 ◽

Cited By ~ 8

Author(s):

Mohamed A.M. El-Awady ◽

Mohamed M. Hassan ◽

Yassin M. Al-Sodany

Keyword(s):

Nitrogen Fixation ◽

Acetic Acid ◽

Plant Growth ◽

Growth Promotion ◽

Exponential Growth Phase ◽

Plant Growth Promoting Bacteria ◽

Salt Tolerant ◽

Isolation And Characterization ◽

Growth Promoting

This study was designed to isolate and characterize endophytic and rhizospheric bacteria associated with the halophyte plant Sesuvium verrucosum, grown under extreme salinity soil in Jeddah, Saudi Arabia. The plant growth promotion activities of isolated bacterial were evaluated in vitro. A total of 19 salt tolerant endophytic and rhizospheric bacterial isolates were obtained and grouped into six according to genetic similarity based on RAPD data. These six isolates were identified by amplification and partial sequences of 16S rDNA as Enterobacter cancerogenus,Vibrio cholerae, Bacillus subtilis, Escherichia coli and two Enterobacter sp. Isolates were then grown until exponential growth phase to evaluate the atmospheric nitrogen fixation, phosphate solubilization, and production of phytohormones such as indole-3-acetic acid, as well as 1-aminocyclopropane-1-carboxylate (ACC) deaminase activity. While, All of the six strains were negative for ACC deaminaseactivity, two isolates showed Nitrogen fixation activity, three isolates produce the plant hormone (Indole acetic acid) and two isolates have the activity of solubiliztion of organic phosphate. Among the six isolates, the isolate (R3) from the soil around the roots is able to perform the three previous growth promoting possibilities together and it is ideal for use in promoting the growth of plants under the high salinity conditions. This isolate is candidate to prepare a friendly biofertelizer that can be used for the improvement of the crops performance under salinity conditions.Int J Appl Sci Biotechnol, Vol 3(3): 552-560

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The Root Microbiome of Salicornia ramosissima as a Seedbank for Plant-Growth Promoting Halotolerant Bacteria

Applied Sciences ◽

10.3390/app11052233 ◽

2021 ◽

Vol 11 (5) ◽

pp. 2233

Author(s):

Maria J. Ferreira ◽

Angela Cunha ◽

Sandro Figueiredo ◽

Pedro Faustino ◽

Carla Patinha ◽

...

Keyword(s):

Plant Growth ◽

Plant Growth Promotion ◽

Growth Promotion ◽

Cultivated Plants ◽

Plant Growth Promoting Bacteria ◽

Crop Cultivation ◽

Halotolerant Bacteria ◽

Salicornia Ramosissima ◽

Plant Growth Promoting ◽

Growth Promoting

Root−associated microbial communities play important roles in the process of adaptation of plant hosts to environment stressors, and in this perspective, the microbiome of halophytes represents a valuable model for understanding the contribution of microorganisms to plant tolerance to salt. Although considered as the most promising halophyte candidate to crop cultivation, Salicornia ramosissima is one of the least-studied species in terms of microbiome composition and the effect of sediment properties on the diversity of plant-growth promoting bacteria associated with the roots. In this work, we aimed at isolating and characterizing halotolerant bacteria associated with the rhizosphere and root tissues of S. ramosissima, envisaging their application in saline agriculture. Endophytic and rhizosphere bacteria were isolated from wild and crop cultivated plants, growing in different estuarine conditions. Isolates were identified based on 16S rRNA sequences and screened for plant-growth promotion traits. The subsets of isolates from different sampling sites were very different in terms of composition but consistent in terms of the plant-growth promoting traits represented. Bacillus was the most represented genus and expressed the wider range of extracellular enzymatic activities. Halotolerant strains of Salinicola, Pseudomonas, Oceanobacillus, Halomonas, Providencia, Bacillus, Psychrobacter and Brevibacterium also exhibited several plant-growth promotion traits (e.g., 3-indole acetic acid (IAA), 1-aminocyclopropane-1-carboxylic acid (ACC) deaminase, siderophores, phosphate solubilization). Considering the taxonomic diversity and the plant-growth promotion potential of the isolates, the collection represents a valuable resource that can be used to optimize the crop cultivation of Salicornia under different environmental conditions and for the attenuation of salt stress in non-halophytes, considering the global threat of arable soil salinization.

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The Effects of Plant Growth-Promoting Bacteria with Biostimulant Features on the Growth of a Local Onion Cultivar and a Commercial Zucchini Variety

Agronomy ◽

10.3390/agronomy11050888 ◽

2021 ◽

Vol 11 (5) ◽

pp. 888

Author(s):

Giorgia Novello ◽

Patrizia Cesaro ◽

Elisa Bona ◽

Nadia Massa ◽

Fabio Gosetti ◽

...

Keyword(s):

Plant Growth ◽

Growth Promotion ◽

Global Market ◽

Plant Growth Promoting Bacteria ◽

Bacterial Strains ◽

Mineral Concentration ◽

Positive Effects ◽

Plant Growth Promoting ◽

Onion Cultivar ◽

Growth Promoting

The reduction of chemical inputs due to fertilizer and pesticide applications is a target shared both by farmers and consumers in order to minimize the side effects for human and environmental health. Among the possible strategies, the use of biostimulants has become increasingly important as demonstrated by the fast growth of their global market and by the increased rate of registration of new products. In this work, we assessed the effects of five bacterial strains (Pseudomonas fluorescens Pf4, P. putida S1Pf1, P. protegens Pf7, P. migulae 8R6, and Pseudomonas sp. 5Vm1K), which were chosen according to their previously reported plant growth promotion traits and their positive effects on fruit/seed nutrient contents, on a local onion cultivar and on zucchini. The possible variations induced by the inoculation with the bacterial strains on the onion nutritional components were also evaluated. Inoculation resulted in significant growth stimulation and improvement of the mineral concentration of the onion bulb, induced particularly by 5Vm1K and S1Pf1, and in different effects on the flowering of the zucchini plants according to the bacterial strain. The present study provides new information regarding the activity of the five plant growth-promoting bacteria (PGPB) strains on onion and zucchini, two plant species rarely considered by the scientific literature despite their economic relevance.

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Isolation, identification and characterization of native plant growth promoting bacteria and their plant growth promotion in Zea mays

Research Journal of Biotechnology ◽

10.25303/168rjbt7521 ◽

2021 ◽

Vol 16 (8) ◽

pp. 75-80

Author(s):

Pitchaiah Pelapudi ◽

Sasikala Ch ◽

Swarnabala Ganti

Keyword(s):

Plant Growth ◽

Plant Growth Promotion ◽

Root Length ◽

Growth Promotion ◽

Shoot Length ◽

Root Weight ◽

Plant Growth Promoting Bacteria ◽

Plant Growth Promoting ◽

Growth Promoting ◽

Shoot Weight

In the present rapid growing world, need for a sustainable agricultural practice which helps in meeting the adequate food demand is much needed. In this context, plant growth promoting bacteria were brought into the spot light by the researchers. Though the plant growth promoting bacteria have several beneficial applications, due to some of the disadvantages in the field conditions, they lagged behind. In the current research work, native PGPR were isolated from the rhizosphere soil samples of maize with an aim to isolate the nitrogen fixing, phosphate solubilising and potash solubilising bacteria. Out of the several isolates, potent PGPR isolates viz., Paenibacillus durus PCPB067, Bacillus megaterium PCBMG041 and Paenibacillus glucanolyticus PCPG051 were isolated and identified by using the 16 S rRNA gene sequencing studies. Genomic DNA sequences obtained were deposited in the NCBI Genbank and accession numbers were assigned as MW793452, MW793456 and MW843633. In order to check the efficacy of the PGPR isolates, pot trials were conducted by taking maize as the host plant. Several parameters viz. shoot length, shoot weight, root length, root weight and weight of the seeds were tested in which PGP treatment showed good results (shoot length - 187±3.5 cm, shoot weight - 31±4 g, root length - 32±3.6 cm, root weight - 17±2 g, yield- 103.3±6.1 g) when compared to the chemical fertilizer treatment (shoot length - 177±3.5 cm, shoot weight - 25±3.6 g, root length - 24±3.5 cm, root weight - 14.6±1.52 g, yield- 85.6±7.6 g). Based on the results, it can be stated that these native PGPR isolates can be effectively used in the plant growth promotion of maize.

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Biofertlizer Lumbrical improves the growth and ex vitro acclimatization of micropropagated pear plants

Silva Balcanica ◽

10.3897/silvabalcanica.22.e57661 ◽

2021 ◽

Vol 22 (1) ◽

pp. 17-30

Author(s):

Nataliya Dimitrova ◽

Lilyana Nacheva ◽

Małgorzata Berova ◽

Danuta Kulpa

Keyword(s):

Woody Species ◽

Photosynthetic Photon Flux Density ◽

Stem Length ◽

Photon Flux ◽

Photon Flux Density ◽

Ex Vitro ◽

Fluorescent Lamps ◽

Planting Material ◽

Number Of Leaves

In vitro micropropagation of plants is highly useful for obtaining large quantities of planting material with valuable economic qualities. However, plantlets grow in vitro in a specific environment and the adaptation after the transfer to ex vitro conditions is difficult. Therefore, the acclimatization is a key step, which mostly determines the success of micropropagation. The aim of this investigation was to study the effect of the biofertlizer Lumbrical on ex vitro acclimatization of micropropagated pear rootstock OHF 333 (Pyrus communis L.). Micropropagated and rooted plantlets were potted in peat and perlite (2:1) mixture with or without Lumbrical. They were grown in a growth chamber at a temperature of 22±2 °C and photoperiod of 16/8 hours supplied by cool-white fluorescent lamps (150 µmol m-2 s-1 Photosynthetic Photon Flux Density, PPFD). The plants were covered with transparent foil to maintain the high humidity, and ten days later, the humidity was gradually decreased. Biometric parameters, anatomic-morphological analyses, net photosynthetic rate and chlorophyll a fluorescence (JIP test) were measured 21 days after transplanting the plants to ex vitro conditions. The obtained results showed that the plants, acclimatized ex vitro in the substrate with Lumbrical, presented better growth (stem length, number of leaves, leaf area and fresh mass) and photosynthetic characteristics as compared to the control plants. This biostimulator could also be used to improve acclimatization in other woody species

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COLONIZATION of Rubus glaucus BENTH BY AZORHIZOBIUM CAULINODANS ORS571 USIG A FLAVONOIDE NARINGENINA

BISTUA REVISTA DE LA FACULTAD DE CIENCIAS BASICAS ◽

10.24054/01204211.v2.n2.2016.2117 ◽

2016 ◽

Vol 14 (2) ◽

pp. 15

Author(s):

Giovani Orlando Cancino Escalante ◽

S E Cancino ◽

Enrique Quevedo Garcia

Keyword(s):

Bacterial Colonization ◽

Lateral Roots ◽

Plant Growth Promoting Bacteria ◽

Azorhizobium Caulinodans ◽

Intensity Parameters ◽

Plant Growth Promoting ◽

Measuring Frequency ◽

Northwest Region ◽

Azorhizobium Caulinodans Ors571

Root systems of two Andean blackberry materials (thorn and thornless) of Rubus glaucus Benth cultured in vitro in the presence of five treatments (four flavonoids and one control) were inoculated with Azorhizobium caulinodans ORS571 (pXLGD4) (a strain carrying the lacZ reporter gene which facilitated the detection of bacterial colonization). Evaluation of colonization effectiveness for each treatment was done by means of application of experimental design measuring frequency and intensity parameters. Statistical analysis showed differences at comparing flavonoids vs. control and the overall higher effectiveness of the flavonoid naringenin. Observation of colonization was made by light and electron microscope confirming internal colonization of Andean blackberry roots by A. caulinodans. This is the first work demonstrating root colonization of R.glaucus by azorhizobia and therefore settling the basis for future investigations and scientific applications related to interaction with plant growth-promoting bacteria under the effect of flavonoids, along with possible implications of common benefit for non-legume crops in the northwest region of Colombia. Key Words: Azorhizobium caulinodans ORS571, Andean blackberry, flavonoids, LacZ, lateral roots, naringenin.

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