Rhizobacterial Inoculants Increase Root and Shoot Growth in ‘Tifway’ Hybrid Bermudagrass

Plant growth-promoting rhizobacteria (PGPR) are non-pathogenic, beneficial bacteria that colonize seeds and roots of plants and enhance plant growth. Although there has been extensive PGPR research with agronomic crops, there has been little emphasis on development of PGPR for grasses in pastures or as turf. Accordingly, experiments were conducted to evaluate novel bacterial inoculants for growth promotion in ‘Tifway’ hybrid bermudagrass. Replicated laboratory and greenhouse experiments evaluated effects of various PGPR mixtures, each with 3 to 5 PGPR strains and applied as weekly root inoculations, in comparison to nontreated plants. Growth promotion was assessed by measuring foliar growth from 3 to 8 wk and root growth at 8 wk after the first treatment. In all experiments, at least one bacterial treatment of bermudagrass resulted in significantly increased top growth and greater root growth (length, surface area, volume, or dry weight). PGPR blends 20 and MC3 caused the greatest growth promotion of roots and shoots. These results suggest that the bacterial strains could be used in strategies to reduce nitrogen or water inputs to turf.

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A gnotobiotic bioassay for studying interactions between potatoes and plant growth-promoting rhizobacteria

Canadian Journal of Microbiology ◽

10.1139/m97-117 ◽

1997 ◽

Vol 43 (9) ◽

pp. 801-808 ◽

Cited By ~ 49

Author(s):

Kenneth L. Conn ◽

George Lazarovits ◽

Jerzy Nowak

Keyword(s):

Plant Growth ◽

Growth Promotion ◽

Potato Cultivar ◽

Fold Increase ◽

Dry Weight ◽

Plant Growth Promoting Rhizobacteria ◽

Single Node ◽

Plant Growth Promoting ◽

Growth Promoting ◽

Potato Plantlets

A gnotobiotic bioassay, using potato plantlets derived from single-node explants and grown in test tubes containing potato nodal cutting medium (PNCM), was found to be highly useful for investigations of direct growth promotion by a nonfluorescent Pseudomonas sp. strain PsJN. Strain PsJN was used to optimize and evaluate this bioassay for purposes of screening other rhizosphere bacteria and identification of Tn5 mutants of strain PsJN deficient in growth-promoting properties. The selection of potato cultivar used in this bioassay was critical, as growth promotion of potatoes by strain PsJN was cultivar specific. Inoculated plantlets of cultivars Norchip, Kennebec, Shepody, and Chaleur showed, in root dry weight, a five- to eight-fold increase, two- to three-fold increase, no response, and a decrease of 50%, respectively. Haulm dry weight followed similar trends but was not as consistent an indicator of growth promotion. Bioassay results were not altered to any extent by minor changes in PNCM composition or by slight changes in temperature and light conditions. A rapid method for preparation of bacterial suspensions and inoculation of explants was developed. Inoculation of three explants taken from 6-week-old stock plantlets of cv. Kennebec for each Tn5 transconjugate of strain PsJN (total of 1500 transconjugates) enabled the elimination of 93% of those isolates that retained growth-promoting activity. The remaining 7% of isolates were retested and seven were confirmed to have lost growth-promoting ability. Bacteria from different genera were also screened with this bioassay. None of these bacteria increased the growth of potato plantlets, but several inhibited root and haulm growth.Key words: plant growth-promoting rhizobacteria, gnotobiotic, tissue culture, nonfluorescent pseudomonad, bacterium, potato.

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First year field performance of spruce seedlings inoculated with plant growth promoting rhizobacteria

Canadian Journal of Microbiology ◽

10.1139/m93-164 ◽

1993 ◽

Vol 39 (11) ◽

pp. 1084-1088 ◽

Cited By ~ 34

Author(s):

C. P. Chanway ◽

F. B. Holl

Keyword(s):

Plant Growth ◽

Growth Promotion ◽

Field Performance ◽

Plant Growth Promoting Rhizobacteria ◽

Growth Promoter ◽

Bacterial Strains ◽

Branch Number ◽

Seedling Biomass ◽

Plant Growth Promoting ◽

Growth Promoting

The influence of plant growth promoting rhizobacteria on field performance of hybrid spruce (Picea glauca × engelmannii) was investigated by inoculating seedlings with rhizobacteria capable of stimulating seedling growth in a controlled environment. Two spruce ecotypes (from Mackenzie and Salmon Arm, British Columbia) and two bacterial strains previously isolated from naturally regenerating seedlings of each spruce ecotype were evaluated. Planting trials were conducted in the ecosystem from which each spruce ecotype and associated bacterial strain were originally collected, and at two alternative sites. Hydrogenophaga pseudoflava, which was isolated from Mackenzie spruce seedlings, caused increases in seedling biomass or branch number of up to 49%, but was most effective as a root growth promoter of the Salmon Arm spruce ecotype. Pseudomonas putida, which originated from Salmon Arm spruce seedlings, increased seedling biomass or branch number in two trials, but had inhibitory effects in three others. There was no indication that growth promotion was related to a common ecotypic origin of seedlings and rhizobacteria, or that bacteria were more effective in the ecosystem from which they were originally isolated. However, Salmon Arm spruce growth promotion by H. pseudoflava was greatest at the poorest quality planting site.Key words: field trials, inoculation, PGPR, spruce.

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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 and their biological properties for soil enrichment and growth promotion

Journal of Plant Nutrition ◽

10.1080/01904167.2021.1952221 ◽

2021 ◽

pp. 1-27

Author(s):

Anjali Chauhan ◽

Raj Saini ◽

Jagjeet Chand Sharma

Keyword(s):

Plant Growth ◽

Growth Promotion ◽

Plant Growth Promoting Rhizobacteria ◽

Biological Properties ◽

Soil Enrichment ◽

Plant Growth Promoting ◽

Growth Promoting

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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 and characterization of plant growth-promoting rhizobacteria from wheat rhizosphere and their effect on plant growth promotion

Frontiers in Microbiology ◽

10.3389/fmicb.2015.00198 ◽

2015 ◽

Vol 6 ◽

Cited By ~ 127

Author(s):

Afshan Majeed ◽

M. Kaleem Abbasi ◽

Sohail Hameed ◽

Asma Imran ◽

Nasir Rahim

Keyword(s):

Plant Growth ◽

Plant Growth Promotion ◽

Growth Promotion ◽

Plant Growth Promoting Rhizobacteria ◽

Wheat Rhizosphere ◽

Isolation And Characterization ◽

Plant Growth Promoting ◽

Growth Promoting

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Perlakuan Rizobakteri Pemacu Pertumbuhan Tanaman (RPPT) dengan Beberapa Tingkat Kerapatan Inokulum Rizobakteri Terhadap Viabilitas dan Vigor Benih Cabai Merah Kadaluarsa (Capsicum annuum L.)

Jurnal Ilmiah Mahasiswa Pertanian ◽

10.17969/jimfp.v4i1.6423 ◽

2020 ◽

Vol 4 (1) ◽

pp. 229-238

Author(s):

Dayang Rahmanita Simanjuntak ◽

Halimursyadah Halimursyadah ◽

Syamsuddin Syamsuddin

Keyword(s):

Plant Growth ◽

Capsicum Annuum ◽

Seed Treatment ◽

Dry Weight ◽

Plant Growth Promoting Rhizobacteria ◽

Seed Vigor ◽

Inoculum Density ◽

Plant Growth Promoting ◽

Actinobacillus Suis ◽

Growth Promoting

Abstrak. Biological seed treatment merupakan salah satu perlakuan benih menggunakan mikroorganisme seperti rizobakteri pemacu pertumbuhan tanaman (RPPT). Penelitian ini bertujuan untuk mengetahui jenis rizobakteri dan kerapatan inokulum yang dapat meningkatkan viabilitas dan vigor benih cabai kadaluarsa. Penelitian ini menggunakan Rancangan Acak Lengkap (RAL) pola faktorial dengan 2 faktor dan 3 ulangan. Faktor pertama adalah jenis rizobakteri (R) terdiri atas lima taraf yaitu R1: Necercia sp; R2:Bacillus polymixa; R3: Actinobacillus suis; R4: Azotobacter sp; R5: Pseudomonas capacia. Faktor kedua adalah kerapatan inokulum rizobakteri terdiri dari tiga taraf yaitu K1: 107 cfu/ml; K2: 108 cfu/ml; K3: 109 cfu/ml. Hasil penelitian ini menunjukkan bahwa perlakuan benih menggunakan rizobakteri jenis Necercia sp dengan kerapatan inokulum 108 cfu/ml nyata meningkatkan vigor benih pada tolok ukur indeks vigor yaitu 40% dan Pseudomonas capacia dengan kerapatan inokulum 109 cfu/ml juga merupakan kombinasi perlakuan terbaik dalam meningkatkan berat kering kecambah normal yaitu 69,33 mg.Treatment Of Plant Growth Promoting Rhizobacteria (PGPR)With Multiple Levels of Rhizobacteria Inoculum Density On Viability and Vigor Of Expired Red Chilli Seeds (Capsicum annuum L.Abstract. Biological seed treatment is one of the seed treatment using microorganisms such as plant growth-promoting rhizobacteria (PGPR). This study aims to determine the type of rhizobacteria and inoculum density that can increase the viability and vigor of expired chili seeds. This research uses Completely Randomized Design (CRD) factorial pattern with 2 factors and 3 replications. The first factor is the type of rhizobacteria (R) consists of five levels, namely R1: Necercia sp; R2: Bacillus polymixa; R3: Actinobacillus suis; R4: Azotobacter sp; R5: Pseudomonas capacia. The second factor is the density of rhizobacteria inoculum consisting of three levels namely K1: 107 cfu/ml; K2: 108 cfu/ml; K3: 109 cfu/ml. The results of this study showed that the seed treatment using the Necercia sp-type rizobacteria with 108 cfu/ml inoculum density significantly increased the seed vigor on the vigor index benchmark of 40% and Pseudomonas capacia with 109cfu/ml inoculum density was also the best treatment combination in increasing dry weight normal sprout is 69,33 mg.

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