Special Abilities of Microbes and Their Application in Agro-Biology

A special issue of Microorganisms (ISSN 2076-2607). This special issue belongs to the section "Environmental Microbiology".

Deadline for manuscript submissions: closed (15 September 2023) | Viewed by 26192

Special Issue Editors


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Guest Editor
Academy of Biology and Biotechnology, Southern Federal University, Rostov-on-Don, Russia
Interests: NRPS; PKS; probiotics; PGPR; antimicrobials
Special Issues, Collections and Topics in MDPI journals

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Guest Editor
Amity Institute of Environmental Toxicology, Safety and Management, Amity University, Noida, U.P, India
Interests: antibiotics compounds; nutraceuticals; industrial applications

Special Issue Information

Dear Colleagues,

Microbes are omnipresent on the earth, and they have adapted very well to any extreme conditions be it, the coldest and driest polar environment, erupting volcanos, hot springs and even deserted and polluted lands. Such adaptation provides resilience through unique physiology and biochemistry by producing a variety of enzymes and metabolites. Several organisms have shown that not only can they tolerate these conditions, but also that they often require these extreme conditions for living. Such adaptation comes from the genomic, structural and metabolic adaptations to cope with their specific environmental conditions.

Adaptation to the deep ocean, highly saline soil, mining areas loaded with metal pollution, cold stressed environment, and heavily polluted soil with synthetic organic pollutants provide them with exceptional capabilities suitable to support sustainable agriculture. Researchers have been exploring the potential of special ability microbes for significant agricultural applications. In this regard, a few areas such as: Harnessing the potential of special ability microbes for improving plant and crop health; Management of plant diseases and biocontrol, Combating environmental stress such as cold, drought and salinity, Soil improvement by improving soil fertility, bioremediation of metal and persistent organic pollutants, and Value-added agricultural products and by-products are crucial in the development of the strategy for agricultural application of special ability microbes.

In this Special Issue of the journal Microorganisms, we invite you to send your articles (research and reviews) in any of the below-mentioned scopes of microbial research:

  • Plant microbes’ interactions and microbes with nutrient solubilizing capabilities
  • Microbial bioactive compounds for crop health and biocontrol
  • Metallotolerant microbes for heavy metal remediation in Agricultural soil
  • Microbial secondary metabolites, PKS, NRPs for potential biotechnological application
  • Bioethanol and methanol production for strengthening microeconomy and steps towards green fuel
  • Transformation /degradation of toxic organic chemicals from the soil/water
  • Microbes-Nanoparticle interaction for soil and plant health improvement

Dr. Anuj Ranjan
Dr. Vishnu D. Rajput
Dr. Abhishek Chauhan
Guest Editors

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Published Papers (11 papers)

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Research

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13 pages, 1741 KiB  
Article
Antifungal Activity of Phyllospheric Bacteria Isolated from Coffea arabica against Hemileia vastatrix
by Katty Ogata-Gutiérrez, Carolina Chumpitaz-Segovia, Jesus Lirio-Paredes and Doris Zúñiga-Dávila
Microorganisms 2024, 12(3), 582; https://doi.org/10.3390/microorganisms12030582 - 14 Mar 2024
Viewed by 606
Abstract
Peru is one of the leading countries that produce and export specialty coffees, favorably positioned in the international markets for its physical and organoleptic cup qualities. In recent years, yellow coffee rust caused by the phytopathogenic fungus Hemileia vastatrix stands out as one [...] Read more.
Peru is one of the leading countries that produce and export specialty coffees, favorably positioned in the international markets for its physical and organoleptic cup qualities. In recent years, yellow coffee rust caused by the phytopathogenic fungus Hemileia vastatrix stands out as one of the main phytosanitary diseases that affect coffee culture yields. Many studies have demonstrated bacteria antagonistic activity against a number of phytopathogen fungi. In this context, the aim of this work was to select and characterize phyllospheric bacteria isolated from Coffea arabica with antagonistic features against coffee rust to obtain biocontrollers. For that purpose, a total of 82 phyllospheric bacteria were isolated from two coffee leaf rust-susceptible varieties, typica and caturra roja, and one tolerant variety, catimor. Of all the isolates, 15% were endophytic and 85% were epiphytes. Among all the isolates, 14 were capable of inhibiting the mycelial radial growth of Mycena citricolor, and Colletotrichum sp. 16S rRNA gene sequence-based analysis showed that 9 isolates were related to Achromobacter insuavis, 2 were related to Luteibacter anthropi and 1 was related to Rodococcus ceridiohylli, Achromobacter marplatensis and Pseudomonas parafulva. A total of 7 representative bacteria of each group were selected based on their antagonistic activity and tested in germination inhibition assays of coffee rust uredinospores. The CRRFLT7 and TRFLT8 isolates showed a high inhibition percentage of urediniospores germination (81% and 82%, respectively), similar to that obtained with the chemical control (91%). An experimental field assay showed a good performance of both strains against rust damage too, making them a promising alternative for coffee leaf rust biocontrol. Full article
(This article belongs to the Special Issue Special Abilities of Microbes and Their Application in Agro-Biology)
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29 pages, 13915 KiB  
Article
Characterization of Growth-Promoting Activities of Consortia of Chlorpyrifos Mineralizing Endophytic Bacteria Naturally Harboring in Rice Plants—A Potential Bio-Stimulant to Develop a Safe and Sustainable Agriculture
by Md. Yeasin Prodhan, Md. Bokhtiar Rahman, Aminur Rahman, Md. Ahedul Akbor, Sibdas Ghosh, Mst. Nur-E-Nazmun Nahar, Simo, Md. Shamsuzzoha, Kye Man Cho and Md. Azizul Haque
Microorganisms 2023, 11(7), 1821; https://doi.org/10.3390/microorganisms11071821 - 16 Jul 2023
Cited by 3 | Viewed by 2445
Abstract
Eighteen pesticide-degrading endophytic bacteria were isolated from the roots, stems, and leaves of healthy rice plants and identified through 16S rRNA gene sequencing. Furthermore, biochemical properties, including enzyme production, dye degradation, anti-bacterial activities, plant-growth-promoting traits, including N-fixation, P-solubilization, auxin production, and ACC-deaminase activities [...] Read more.
Eighteen pesticide-degrading endophytic bacteria were isolated from the roots, stems, and leaves of healthy rice plants and identified through 16S rRNA gene sequencing. Furthermore, biochemical properties, including enzyme production, dye degradation, anti-bacterial activities, plant-growth-promoting traits, including N-fixation, P-solubilization, auxin production, and ACC-deaminase activities of these naturally occurring endophytic bacteria along with their four consortia, were characterized. Enterobacter cloacae HSTU-ABk39 and Enterobacter sp. HSTU-ABk36 displayed inhibition zones of 41.5 ± 1.5 mm, and 29 ± 09 mm against multidrug-resistant human pathogenic bacteria Staphylococcus aureus and Staphylococcus epidermidis, respectively. FT-IR analysis revealed that all eighteen isolates were able to degrade chlorpyrifos pesticide. Our study confirms that pesticide-degrading endophytic bacteria from rice plants play a key role in enhancing plant growth. Notably, rice plants grown in pots containing reduced urea (30%) mixed with either endophytic bacterial consortium-1, consortium-2, consortium-3, or consortia-4 demonstrated an increase of 17.3%, 38.6%, 18.2%, and 39.1% yields, respectively, compared to the control plants grown in pots containing 100% fertilizer. GC–MS/MS analysis confirmed that consortia treatment caused the degradation of chlorpyrifos into different non-toxic metabolites, including 2-Hydroxy-3,5,6 trichloropyridine, Diethyl methane phosphonate, Phorate sulfoxide, and Carbonochloridic. Thus, these isolates could be deployed as bio-stimulants to improve crop production by creating a sustainable biological system. Full article
(This article belongs to the Special Issue Special Abilities of Microbes and Their Application in Agro-Biology)
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17 pages, 2218 KiB  
Article
Role of Rahnella aquatilis AZO16M2 in Phosphate Solubilization and Ex Vitro Acclimatization of Musa acuminata var. Valery
by Daniela Landa-Acuña, Marcia Toro, Ricardo Santos-Mendoza and Doris Zúñiga-Dávila
Microorganisms 2023, 11(6), 1596; https://doi.org/10.3390/microorganisms11061596 - 16 Jun 2023
Cited by 2 | Viewed by 1160
Abstract
Rahnella aquatilis AZO16M2, was characterized for its phosphate solubilization capacity to improve the establishment and survival of Musa acuminata var. Valery seedlings under ex-acclimation. Three phosphorus sources (Rock Phosphate (RF), Ca3(PO4)2 and K2HPO4) and [...] Read more.
Rahnella aquatilis AZO16M2, was characterized for its phosphate solubilization capacity to improve the establishment and survival of Musa acuminata var. Valery seedlings under ex-acclimation. Three phosphorus sources (Rock Phosphate (RF), Ca3(PO4)2 and K2HPO4) and two types of substrate (sand:vermiculite (1:1) and Premix N°8) were selected. The factorial analysis of variance (p < 0.05) showed that R. aquatilis AZO16M2 (OQ256130) solubilizes Ca3(PO4)2 in solid medium, with a Solubilization Index (SI) of 3.77 at 28 °C (pH 6.8). In liquid medium, it was observed that R. aquatilis produced 29.6 mg/L soluble P (pH 4.4), and synthesized organic acids (oxalic, D-gluconic, 2-ketogluconic and malic), Indole Acetic Acid (IAA) (33.90 ppm) and siderophores (+). Additionally, acid and alkaline phosphatases (2.59 and 2.56 µg pNP/mL/min) were detected. The presence of the pyrroloquinoline-quinone (PQQ) cofactor gene was confirmed. After inoculating AZO16M2 to M. acuminata in sand:vermiculite with RF, the chlorophyll content was 42.38 SPAD (Soil Plant Analysis Development). Aerial fresh weight (AFW), aerial dry weight (ADW) and root dry weight (RDW) were superior to the control by 64.15%, 60.53% and 43.48%, respectively. In Premix N°8 with RF and R. aquatilis, 8.91% longer roots were obtained, with 35.58% and 18.76% more AFW and RFW compared with the control as well as 94.45 SPAD. With Ca3(PO4)2, values exceeded the control by 14.15% RFW, with 45.45 SPAD. Rahnella aquatilis AZO16M2 favored the ex-climatization of M. acuminata through improving seedling establishment and survival. Full article
(This article belongs to the Special Issue Special Abilities of Microbes and Their Application in Agro-Biology)
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14 pages, 8234 KiB  
Article
Assessing the Sensitivity of Plasmopara halstedii Isolates to Mefenoxam through Host Responses
by Nisha Nisha, Sergey Vinogradov, Katalin Körösi, Arbnora Berisha and Rita Bán
Microorganisms 2023, 11(4), 821; https://doi.org/10.3390/microorganisms11040821 - 23 Mar 2023
Viewed by 955
Abstract
Downy mildew caused by Plasmopara halstedii is responsible for significant economic losses in cultivated sunflowers. Field isolates of sunflower downy mildew resistant to mefenoxam, a previously effective active ingredient against the pathogen, have been found across Europe. The main goal of this study [...] Read more.
Downy mildew caused by Plasmopara halstedii is responsible for significant economic losses in cultivated sunflowers. Field isolates of sunflower downy mildew resistant to mefenoxam, a previously effective active ingredient against the pathogen, have been found across Europe. The main goal of this study was to assess the sensitivity of P. halstedii isolates to mefenoxam through host responses to infection, such as symptoms measured by disease severity and growth reduction, and host tissue reactions, such as hypersensitive reaction and necrosis of invaded cells. Sunflower seeds were treated with Apron XL 350 FS at the European registered rate (3 mg/kg seeds). Seedlings were inoculated using the soil drench method with eight Hungarian P. halstedii isolates. Disease rates and plant heights were measured twice. Histological examinations of cross-sections of sunflower hypocotyls were performed using a fluorescence microscope. In our study, cluster analyses of sunflowers based on macroscopic and microscopic variables showed differentiation of groups of mefenoxam-treated sunflowers inoculated with different P. halstedii isolates. We first revealed a clear difference in host responses of mefenoxam-treated susceptible sunflowers. In addition, examining tissue reactions (e.g., hypersensitive reaction, necrosis) seems more accurate to estimate the sensitivity of P. halstedii isolates to mefenoxam than macroscopic symptoms. Full article
(This article belongs to the Special Issue Special Abilities of Microbes and Their Application in Agro-Biology)
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21 pages, 5689 KiB  
Article
Nanofungicides with Selenium and Silicon Can Boost the Growth and Yield of Common Bean (Phaseolus vulgaris L.) and Control Alternaria Leaf Spot Disease
by Naglaa A. Taha, Salem Hamden, Yousry A. Bayoumi, Tamer Elsakhawy, Hassan El-Ramady and Svein Ø. Solberg
Microorganisms 2023, 11(3), 728; https://doi.org/10.3390/microorganisms11030728 - 11 Mar 2023
Cited by 8 | Viewed by 2310
Abstract
There is an urgent need to reduce the intensive use of chemical fungicides due to their potential damage to human health and the environment. The current study investigated whether nano-selenium (nano-Se) and nano-silica (nano-SiO2) could be used against the leaf spot [...] Read more.
There is an urgent need to reduce the intensive use of chemical fungicides due to their potential damage to human health and the environment. The current study investigated whether nano-selenium (nano-Se) and nano-silica (nano-SiO2) could be used against the leaf spot disease caused by Alternaria alternata in a common bean (Phaseolus vulgaris L.). The engineered Se and SiO2 nanoparticles were compared to a traditional fungicide and a negative control with no treatment, and experiments were repeated during two successive seasons in fields and in vitro. The in vitro study showed that 100 ppm nano-Se had an efficacy rate of 85.1% on A. alternata mycelial growth, followed by the combined applications (Se + SiO2 at half doses) with an efficacy rate of 77.8%. The field study showed that nano-Se and the combined application of nano-Se and nano-SiO2 significantly decreased the disease severity of A. alternata. There were no significant differences among nano-Se, the combined application, and the fungicide treatment (positive control). As compared to the negative control (no treatment), leaf weight increased by 38.3%, the number of leaves per plant by 25.7%, chlorophyll A by 24%, chlorophyll B by 17.5%, and total dry seed yield by 30%. In addition, nano-Se significantly increased the enzymatic capacity (i.e., CAT, POX, PPO) and antioxidant activity in the leaves. Our current study is the first to report that the selected nano-minerals are real alternatives to chemical fungicides for controlling A. alternata in common beans. This work suggests the potential of nanoparticles as alternatives to fungicides. Further studies are needed to better understand the mechanisms and how different nano-materials could be used against phytopathogens. Full article
(This article belongs to the Special Issue Special Abilities of Microbes and Their Application in Agro-Biology)
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19 pages, 7214 KiB  
Article
Influence of Probiotic Feed Supplement on Nosema spp. Infection Level and the Gut Microbiota of Adult Honeybees (Apis mellifera L.)
by Ivana Tlak Gajger, Srebrenka Nejedli and Luka Cvetnić
Microorganisms 2023, 11(3), 610; https://doi.org/10.3390/microorganisms11030610 - 28 Feb 2023
Cited by 2 | Viewed by 2338
Abstract
Honeybees’ gut microbiota can provide new valuable access into the pathogenesis-related factors included in infections. Hence, we researched the presence and comparison of gut microbiota groups in control and Nosema spp.-infected honeybee colonies through high-throughput sequencing of the 16S rRNA. As the newest [...] Read more.
Honeybees’ gut microbiota can provide new valuable access into the pathogenesis-related factors included in infections. Hence, we researched the presence and comparison of gut microbiota groups in control and Nosema spp.-infected honeybee colonies through high-throughput sequencing of the 16S rRNA. As the newest approach in apiary management, we hypothesize that the EM® probiotic for bees could have an important role in therapeutic and immunomodulatory effects on honeybee colonies. The aim of this study was to estimate its impact on the gut microbiota composition of adult honeybees. The major genera were detected, where Lactobacillus was the most abundant genus, followed by Gilliamela, Snodgrassella, and Bifidobacterium. Inoculation with Nosema spp. spores made the relative proportions of Bifidobacterium lower, which was ameliorated by EM® for bees’ application. In addition, EM® for bee applied treatments suppressed the increase in the number of Nosema spp. spores. This result points out that continuous EM® for bees treatment shall change bees’ gut microbiome composition and mitigate the influence of Nosema spp. infection. Snodgrassella alvi was a major member of the honeybee gut microbiota and may be significantly increased by long-term treatment with EM® for bees. Toward these results, it is possible that EM® for bees treatment will protect honeybees from herbicide glyphosate negative effects in agricultural fields by improving microbiome and immune functions. Full article
(This article belongs to the Special Issue Special Abilities of Microbes and Their Application in Agro-Biology)
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16 pages, 2805 KiB  
Article
Improvement of the Nutraceutical Profile of Brewer’s Spent Grain after Treatment with Trametes versicolor
by Anđela Zeko-Pivač, Anja Bošnjaković, Mirela Planinić, Jelena Parlov Vuković, Predrag Novak, Tomislav Jednačak and Marina Tišma
Microorganisms 2022, 10(11), 2295; https://doi.org/10.3390/microorganisms10112295 - 19 Nov 2022
Cited by 6 | Viewed by 2289
Abstract
Brewer’s spent grain (BSG) is an important secondary raw material that provides a readily available natural source of nutraceuticals. It finds its largest application as animal feed and part of the human diet, while the future perspective predicts an application in the production [...] Read more.
Brewer’s spent grain (BSG) is an important secondary raw material that provides a readily available natural source of nutraceuticals. It finds its largest application as animal feed and part of the human diet, while the future perspective predicts an application in the production of value-added products. In order to investigate a sustainable BSG treatment method, two BSG samples (BSG1 and BSG2) were evaluated as substrates for the production of hydrolytic (xylanase, β-glucosidase and cellulase) and lignolytic enzymes (laccase, manganese peroxidase and lignin peroxidase) by solid-state fermentation (SSF) with Trametes versicolor while improving BSG nutritional value. The biological treatment was successful for the production of all hydrolytic enzymes and laccase and manganese peroxidase, while it was unsuccessful for the production of lignin peroxidase. Because the two BSGs were chemically different, the Trametes versicolor enzymes were synthesized at different fermentation times and had different activities. Consequently, the chemical composition of the two BSG samples at the end of fermentation was also different. The biological treatment had a positive effect on the increase in protein content, ash content, polyphenolic compounds, and sugars in BSG1. In BSG2, there was a decrease in the content of reducing sugars. Cellulose, hemicellulose, and lignin were degraded in BSG1, whereas only cellulose was degraded in BSG2, and the content of hemicellulose and lignin increased. The fat content decreased in both samples. The safety-related correctness analysis showed that the biologically treated sample did not contain any harmful components and was therefore safe for use in nutritionally enriched animal feed. Full article
(This article belongs to the Special Issue Special Abilities of Microbes and Their Application in Agro-Biology)
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19 pages, 3720 KiB  
Article
Effects of Below-Ground Microbial Biostimulant Trichoderma harzianum on Diseases, Insect Community, and Plant Performance in Cucurbita pepo L. under Open Field Conditions
by Pierluigi Forlano, Stefania Mirela Mang, Vittoria Caccavo, Paolo Fanti, Ippolito Camele, Donatella Battaglia and Vincenzo Trotta
Microorganisms 2022, 10(11), 2242; https://doi.org/10.3390/microorganisms10112242 - 12 Nov 2022
Cited by 1 | Viewed by 1650
Abstract
Agrochemicals are generally used in agriculture to maximize yields and product quality, but their overuse can cause environmental pollution and human health problems. To reduce the off-farm input of chemicals, numerous biostimulant products based on beneficial symbiont plant fungi are receiving a great [...] Read more.
Agrochemicals are generally used in agriculture to maximize yields and product quality, but their overuse can cause environmental pollution and human health problems. To reduce the off-farm input of chemicals, numerous biostimulant products based on beneficial symbiont plant fungi are receiving a great deal of attention. The evolution of plant diseases and the performance of insects are influenced by plant chemical defences, both of which are, in turn, influenced by below-ground symbionts. Direct and indirect plant defences mediated by belowground symbionts against plant diseases and insect herbivores were demonstrated in greenhouses experiments. However, little attention has been paid to the use of Trichoderma under open field conditions, and no data are available for zucchini (Cucurbita pepo L.) plants in the field. To determine the effects of a commercial Trichoderma harzianum strain T22 on plant viruses, powdery mildew, the arthropod community, and on the agronomic performance associated with zucchini plants, an experiment was conducted in 2022 under open field conditions in South Italy. Our results indicate that T. harzianum T22 makes zucchini plants more attractive to aphids and to Hymenoptera parasitoid but failed to control zucchini pathogens. The complex plant–disease–arthropod–microorganism interactions that occurred in the field during the entire plant cycle are discussed to enrich our current information on the possibilities of using these microorganisms as a green alternative in agriculture. Full article
(This article belongs to the Special Issue Special Abilities of Microbes and Their Application in Agro-Biology)
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13 pages, 1058 KiB  
Article
Plant Growth-Promoting Activities of Bacteria Isolated from an Anthropogenic Soil Located in Agrigento Province
by Pietro Barbaccia, Raimondo Gaglio, Carmelo Dazzi, Claudia Miceli, Patrizia Bella, Giuseppe Lo Papa and Luca Settanni
Microorganisms 2022, 10(11), 2167; https://doi.org/10.3390/microorganisms10112167 - 31 Oct 2022
Cited by 5 | Viewed by 2315
Abstract
Bacteria producers of plant growth-promoting (PGP) substances are responsible for the enhancement of plant development through several mechanisms. The purpose of the present work was to evaluate the PGP traits of 63 bacterial strains that were isolated from an anthropogenic soil, and obtained [...] Read more.
Bacteria producers of plant growth-promoting (PGP) substances are responsible for the enhancement of plant development through several mechanisms. The purpose of the present work was to evaluate the PGP traits of 63 bacterial strains that were isolated from an anthropogenic soil, and obtained by modification of vertisols in the Sicily region (Italy) seven years after creation. The microorganisms were tested for the following PGP characteristics: indole acetic acid (IAA), NH3, HCN and siderophore production, 1-aminocyclopropane-1-carboxylate deaminase activity (ACC) and phosphate solubilization. The results of principal component analysis (PCA) showed that Bacillus tequilensis SI 319, Brevibacterium frigoritolerans SI 433, Pseudomonas lini SI 287 and Pseudomonas frederiksbergensis SI 307 expressed high levels of IAA and production of ACC deaminase enzyme, while for the rest of traits analyzed the best performances were registered with Pseudomonas genus, in particular for the strains Pseudomonas atacamensis SI 443, Pseudomonas reinekei SI 441 and Pseudomonas granadensis SI 422 and SI 450. The in vitro screening provided enough evidence for future in vivo growth promotion tests of these eight strains. Full article
(This article belongs to the Special Issue Special Abilities of Microbes and Their Application in Agro-Biology)
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13 pages, 2498 KiB  
Article
Biofertilizer Based on Biochar and Metal-Tolerant Plant Growth Promoting Rhizobacteria Alleviates Copper Impact on Morphophysiological Traits in Brassica napus L.
by Adarsh Kumar, Galina Borisova, Maria Maleva, Tripti, Grigory Shiryaev, Anastasia Tugbaeva, Artem Sobenin and Irina Kiseleva
Microorganisms 2022, 10(11), 2164; https://doi.org/10.3390/microorganisms10112164 - 31 Oct 2022
Cited by 5 | Viewed by 1836
Abstract
Metal tolerant plant growth-promoting (PGP) rhizobacteria are promising for enhancing plant productivity under copper (Cu) stress. Present pot scale experiment was conducted on Brassica napus L. to check the efficiency of rhizobacteria isolated from the rhizosphere of Tussilago farfara L. growing on Cu-contaminated [...] Read more.
Metal tolerant plant growth-promoting (PGP) rhizobacteria are promising for enhancing plant productivity under copper (Cu) stress. Present pot scale experiment was conducted on Brassica napus L. to check the efficiency of rhizobacteria isolated from the rhizosphere of Tussilago farfara L. growing on Cu-contaminated soils. Out of fifty Cu tolerant strains, three isolates which showed multiple PGP traits such as indole-3-acetic acid (IAA) synthesis, phosphate (PS) solubilization, siderophore and ammonia production were identified preliminarily by morphological and physiological characteristics followed by 16S rRNA gene sequencing. The best Bacillus altitudinis strain TF16a which showed IAA: 15.5 mg L−1, PS: 215 mg L−1, siderophore halo zone ratio of 3.0 with high ammonia production was selected to prepare a biochar-based biofertilizer (BF). Seedling test showed maximum growth of B. napus shoot and root in presence of 5% of BF and this concentration was selected for further experiment. The pot experiment included four treatments: control (soil), 100Cu (100 mg Cu kg−1 soil), 5%BF (v/v), and 5%BF+100Cu, which were carried out for 30 days, after which the morphological, physiological, and biochemical parameters of B. napus were studied. The Cu treatment caused its accumulation in shoot and root up to 16.9 and 30.4 mg kg−1 DW, respectively, and increased malondialdehyde (MDA) content by 20%. Application of BF with copper led to the decrease in the Cu accumulation by 20% for shoot and 28% for root while MDA content was the same as in the control. Both treatments of BF with and without Cu increased chlorophyll a and b content by 1.3 times on average as well as non-enzymatic antioxidants such as soluble phenolic compounds (1.3 times) and free proline (1.6 times). Moreover, BF + Cu led to the increase in the biomass of shoot and root by 30 and 60%, respectively, while there was no significant effect on the growth characteristics of plants after the addition of BF without Cu. The study elucidates that BF based on B.altitudinis strain TF16a and biochar can be a promising bioformulation which could increase rapeseed growth under the moderate Cu concentration in soil. Full article
(This article belongs to the Special Issue Special Abilities of Microbes and Their Application in Agro-Biology)
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Review

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22 pages, 1054 KiB  
Review
Solid-State Fermentation: Applications and Future Perspectives for Biostimulant and Biopesticides Production
by Alessandro Mattedi, Enrico Sabbi, Beatrice Farda, Rihab Djebaili, Debasis Mitra, Claudia Ercole, Paola Cacchio, Maddalena Del Gallo and Marika Pellegrini
Microorganisms 2023, 11(6), 1408; https://doi.org/10.3390/microorganisms11061408 - 26 May 2023
Cited by 8 | Viewed by 5738
Abstract
With the expansion of the green products market and the worldwide policies and strategies directed toward a green revolution and ecological transition, the demand for innovative approaches is always on the rise. Among the sustainable agricultural approaches, microbial-based products are emerging over time [...] Read more.
With the expansion of the green products market and the worldwide policies and strategies directed toward a green revolution and ecological transition, the demand for innovative approaches is always on the rise. Among the sustainable agricultural approaches, microbial-based products are emerging over time as effective and feasible alternatives to agrochemicals. However, the production, formulation, and commercialization of some products can be challenging. Among the main challenges are the industrial production processes that ensure the quality of the product and its cost on the market. In the context of a circular economy, solid-state fermentation (SSF) might represent a smart approach to obtaining valuable products from waste and by-products. SSF enables the growth of various microorganisms on solid surfaces in the absence or near absence of free-flowing water. It is a valuable and practical method and is used in the food, pharmaceutical, energy, and chemical industries. Nevertheless, the application of this technology in the production of formulations useful in agriculture is still limited. This review summarizes the literature dealing with SSF agricultural applications and the future perspective of its use in sustainable agriculture. The survey showed good potential for SSF to produce biostimulants and biopesticides useful in agriculture. Full article
(This article belongs to the Special Issue Special Abilities of Microbes and Their Application in Agro-Biology)
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