Stimulate Plant Growth Research Articles

Exploring the Relationship Between Biochar Pore Structure and Microbial Community Composition in Promoting Tobacco Growth

The potential benefits of biochar, a carbon-rich substance derived from biomass, for enhancing agricultural yield and soil health have drawn increasing interest. Nevertheless, owing to the lack of specialized studies, the role of its poly-spatial structure in the success of fostering plant growth remains unclear. This study aimed to assess the effects of various biochar pore shapes on tobacco growth and the underlying microbiological processes. Three pyrolysis temperatures (250 °C, 400 °C, and 550 °C) were used to produce biochar from tobacco stems, resulting in different pore structures (T3 > T2 > T1). We then used BET-specific surface area (BET), t.Plot micropore specific surface area (t.Plot), mesopore specific surface area (MSSA), specific pore volume (SPV), average pore size (AP), and mesopore pore volume (MPV) measurements to evaluate the effects of these biochars on tobacco growth and biomass accumulation, and microbial analyses were performed to investigate the underlying mechanisms. When applied to plants, biochar increased their growth compared to untreated controls. The most notable improvement in tobacco growth was observed in the biochar produced at 400 °C (T3), which possessed the largest and most advantageous pore structure among all treatments. Further studies demonstrated that biochars with greater specific surface areas (BET, t.Plot, and MSSA) positively altered the abundance of key microbial taxa (e.g., Stenotrophobacter, Ensifer, Claroideoglomus) and community composition, thereby encouraging plant development and biomass accumulation. Conversely, greater pore volumes (SPV, AP, and MPV) inhibited microbial activity and significantly affected growth and biomass accumulation. Structural equation modeling further demonstrated that the pore structure of biochar greatly affected plant growth by changing the relative abundance and community composition of soil microbes. Maximizing the benefits of biochar in stimulating plant growth and improving soil microbial communities depends on optimizing the material’s pore structure, particularly by increasing the specific surface area. These findings will help expand the use of biochar in sustainable agriculture.

Unveiling the hidden world: How arbuscular mycorrhizal fungi and its regulated core fungi modify the composition and metabolism of soybean rhizosphere microbiome

BackgroundThe symbiosis between arbuscular mycorrhizal fungi (AMF) and plants often stimulates plant growth, increases agricultural yield, reduces costs, thereby providing significant economic benefits. AMF can also benefit plants through affecting the rhizosphere microbial community, but the underlying mechanisms remain unclear. Using Rhizophagus intraradices as a model AMF species, we assessed how AMF influences the bacterial composition and functional diversity through 16 S rRNA gene sequencing and non-targeted metabolomics analysis in the rhizosphere of aluminum-sensitive soybean that were inoculated with pathogenic fungus Nigrospora oryzae and phosphorus-solubilizing fungus Talaromyces verruculosus in an acidic soil.ResultsThe inoculation of R. intraradices, N. oryzae and T. verruculosus didn’t have a significant influence on the levels of soil C, N, and P, or various plant characteristics such as seed weight, crude fat and protein content. However, their inoculation affected the structure, function and nutrient dynamics of the resident bacterial community. The co-inoculation of T. verruculosus and R. intraradices increased the relative abundance of Pseudomonas psychrotolerans, which was capable of N-fixing and was related to cry-for-help theory (plants signal for beneficial microbes when under stress), within the rhizosphere. R. intraradices increased the expression of metabolic pathways associated with the synthesis of unsaturated fatty acids, which was known to enhance plant resistance under adverse environmental conditions. The inoculation of N. oryzae stimulated the stress response inside the soil environment by enriching the polyene macrolide antifungal antibiotic-producing bacterial genus Streptomyces in the root endosphere and upregulating two antibacterial activity metabolic pathways associated with steroid biosynthesis pathways in the rhizosphere. Although inoculation of pathogenic fungus N. oryzae enriched Bradyrhizobium and increased soil urease activity, it had no significant effects on biomass and N content of soybean. Lastly, the host niches exhibited differences in the composition of the bacterial community, with most N-fixing bacteria accumulating in the endosphere and Rhizobium vallis only detected in the endosphere.ConclusionsOur findings demonstrate that intricate interactions between AMF, associated core fungi, and the soybean root-associated ecological niches co-mediate the regulation of soybean growth, the dynamics of rhizosphere soil nutrients, and the composition, function, and metabolisms of the root-associated microbiome in an acidic soil.

Isolation and characterization of salt-stress-tolerant rhizosphere soil bacteria and their effects on plant growth-promoting properties

PGPR has a higher potential impact on agricultural crops. It enhances plant growth and development in a variety of adverse environmental conditions, including biotic and abiotic stresses. The PGPR is commercially vital since it is more efficient, safe for the environment, and beneficial to the economy. Nowadays, salt stress has an impact on the agricultural ecosystem. Salt-tolerant PGPR can directly stimulate plant growth and development by producing a variety of metabolites and phytohormones. The current study looked at the isolation of salt-tolerant bacterial species and their ability to stimulate plant development. Four bacterial species were chosen for their better salt stress tolerance (0–5%). They were identified by 16S rRNA sequencing: Solibacillus silvestris BR1, Peribacillus frigoritolerans BR2, Paenibacillus taichungensis CR1, and Solibacillus isronensis CR2. These strains were positive production of indole acetic acid with varying incubation periods (19.66 ± 1.528 to 646.111 ± 8.058 µg/mL), salt stress (ranging from 29.556 ± 1.171 to 147.8111 ± 2.086 µg/mL), phosphate solubilization (0.145 ± 0.011 to 0.921 ± 0.007 µg/mL), ammonium production (0.299 ± 0.047 to 1.202 ± 0.142 µg/mL), HCN production (0.308 ± 0.051 to 4.269 ± 0.069 µg/mL), and siderophore production (0.190 ± 0.064 to 1.543 ± 0.108 µg/mL) for control strains were used without salt stress. The production level was expressed using a standard curve containing various standards.

Harnessing the power of rhizosphere bacteria for pollution remediation: strategies, mechanisms, and environmental impact: A review

This review explores into the sizeable potential of rhizosphere bacteria as effective mediators in the pollution remediation. These rhizosphere bacteria are primarily found in the soil surrounding plant roots, and they have an extremely strong ability to remove a wide range of toxins from the environment. This is attuned with the idea of phytoremediation, which is the use of plants to clean adulterated soil or water. In addition to vigorous participation in bioremediation processes, their diverse activities include stimulating plant growth and serving as biocontrol agents against plant diseases. Their ability to gather, change, and restrain pollutants is one of their main advantages, especially when used in combination with phytoremediation techniques. To fully utilize these microorganisms, it is essential to understand the various bacterial strains and their complex biological pathways that influence their behavior. The diversity and richness of rhizosphere bacterial populations, significantly affected by different plant species and environmental factors, is a crucial area that requires further study. Grasping this heterogeneity is essential for adapting phytoremediation strategies to particular contamination situations and exploiting their effectiveness. Rhizosphere microorganisms present a feasible path towards a more supportable and clean future. This might potentially make a big contribution to environmental restoration efforts in a world that is always changing.

Synthesis and characterization of novel dithiocarbamic thioanhydrides and their application for plant growth stimulant and phytotoxic activity

In this study, nineteen thioanhydrides were synthesized from the S-acylation reaction of sodium dithiocarbamates with various acyl chlorides in chloroform at room temperature. The synthesized thioanhydrides were evaluated for their growth-stimulating and phytotoxic activities. Benzoic (1a), 4-methoxy- (1b), 4-chloro- (1c), 2-bromo- (1e), 4-fluoro- (1f.) and 4-nitrobenzoic 1H-1,2,4-triazole-1-carbothioic thioanhydrides (1 g) showed moderate to excellent growth-stimulating activity, along with this (1c) exhibited excellent phytotoxic activity, 2,4-dichlorobenzoic 1H-1,2,4-triazole-1-carbothioic thioanhydride (1d) and 2,4-dichlorobenzoic pyrrolidine-1-carbothioic thioanhydride (2b) demonstrated inhibiting and moderate phytotoxic activities. Thioanhydrides (1a-c, 1f., 1 g) exhibited excellent germination energy and germination capacity of wheat seeds: 1a 82 and 90%, 1c 80 and 84%, 1 g 82 and 90% (0.01 mg/ml); 1b, 1 g 78 and 94%, 1c 78 and 90%, 1f. 80 and 94% (0.1 mg/ml). Thioanhydride (1e) showed moderate activity, germination energy and germination capacity were 72 and 76% (0.1 mg/ml), 78 and 84% (0.01 mg/ml). Thioanhydride (1d) demonstrated activity as a growth inhibitor with germination energy, and germination capacity 54 and 58% (0.1 mg/ml), 44 and 42% (0.01 mg/ml). Thioanhydride (1c) exhibited excellent phytotoxic activity analogically to herbicide 2,4-D only on lettuce seeds. Compounds (1d and 2b) were moderately active, inhibiting the growth of lettuce and bent grass seedlings.

Associations of Arbuscular Mycorrhizal Fungi (AMF) for Enhancements in Soil Fertility and Promotion of Plant Growth: A Review

Arbuscular Mycorrhizal Fungi are used for soil fertility enhancements and stimulating plant growth in which they association with other organisms like terrestrial plants. Mycorrhizas create an association between fungi and the roots of plants. Therefore, the review was made to point out important fungal species involved in fungal plant interaction and their major roles in agriculture as well as ecosystem. 80% of plants form associations with mycorrhizal fungi. The fungal are used to use their different organs like chain, arbuscular, vesicle, supportive cells and spore to interact with the other plant/ plat’s organ. The mycorrhizal fungi can be categorized into two principal classifications based on their anatomical interactions with the roots of host plants. Arbuscular Mycorrhizal and Ectomycorrhizal fungi utilize two distinct strategies for nutrient acquisition. The main categories of vesicular arbuscular mycorrhizal associations are linear or coiling and of ectomycorrhizal associations are epidermal or cortical. The rhizospheric and endophytic microbes promote plant growth as inoculated with crop. AM fungi as an obligate symbiont share a distinct feature called arbuscules as a site of nutrient exchanges between host and fungi. Arbuscules developed between cell wall and plasma membrane of root cortical cells and differentiated from plant plasma membrane by periarbuscular membrane. Arbuscular mycorrhizal fungi (AMF) play an indispensable role in augmenting plant nutrient acquisition, enhancing plant resilience and tolerance to various environmental stresses, improving soil fertility and structure, and providing numerous beneficial effects. AMF engage in interactions with other soil microorganisms, such as plant growth-promoting rhizobacteria, resulting in a synergistic effect that promotes plant growth and offers protection against pathogens associated with Rhizobia. Both AMF and Rhizobia utilize the same signaling pathways, which facilitate their association with host plants and enable nitrogen fixation within the soil ecosystem. A positive relationship has been established between AMF colonization and the diversity of soil microbial communities. Nitrogen-fixing rhizobia, mycorrhizal fungi, and root nodule symbioses typically exhibit synergistic interactions concerning infection rates and their effects on mineral nutrition and plant growth, thereby significantly enhancing the status of soil fertility, particularly with respect to soil quality characteristics.

Application of Pyroligneous Acid as a Plant Growth Stimulant Can Improve the Nutritional Value of Soybean Seed

Farmers today are using biochemical treatments to improve their crop yields. Commercialized organic biostimulants exist in the form of pyroligneous acid generated by burning agricultural waste products. During the 2023 growing season, we demonstrated that soil treatment with a commercial pyroligneous acid product, Coriphol™, manufactured by Corigin Solutions, Inc., stimulated plant growth and significantly improved yield with an optimal treatment dose of 2 gal. acre−1. In the present work, we examined the effect of this treatment on soybean nutritional content using seed harvested from the 2023 season. Total mean seed protein content for untreated control plants was 32.26 ± 0.49% of dry mass and increased 10.8% to 35.64 ± 0.64% with treatment. This increase resulted in a net reduction in total free amino acid content, although levels of the essential dietary amino acid, lysine, were boosted 6-fold. Total lipid content was unaffected by treatment with mean levels of 21.61 ± 0.70% of dry mass noted. Treatment, however, reduced saturated fatty acid content by roughly 40%, and reduced the polyunsaturated content of linoleic acid in favor of the monounsaturated fatty acid, oleic acid. Finally, Coriphol™ treatment did not impact seed content of eight essential micronutrients including Na, Mg, K, Ca, Fe, Ni, Cu, and Mo, but did significantly boost Zn and Mn levels. Altogether, these results demonstrate that soil treatment with the growth stimulant Coriphol™ has the potential to improve the dietary nutritional value of soybean.

The Effect of Plant Growth-Promoting Bacteria Bacillus subtilis IB-22 on the Hydraulic Conductivity and Abundance of PIP2 Aquaporins in the Roots of an Abscisic Acid-Deficient Barley Mutant.

Little information is available on how rhizosphere bacteria affect abscisic acid (ABA) levels in plants and whether these bacterial effects are associated with improved plant water status. In this study, we tested the hypothesis that the stimulation of plant growth may be associated with the ability of ABA to increase the hydraulic conductivity of roots through the up-regulation of aquaporin. To do this, we studied the effect of bacteria capable of producing ABA on a barley mutant deficient in this hormone. Measurements of hydraulic conductivity of the ABA-deficient barley mutant Az34 showed that its tissues exhibited a reduced ability to conduct water, which correlated with lower ABA content in plants. The inoculation of Bacillus subtilis IB-22 stimulated the growth of both the mutant and its parent variety. Also, under the influence of bacteria, the ABA content in plants increased, and the increase was more significant in the mutant. This effect was accompanied by an increase in hydraulic conductivity in the roots of the ABA-deficient mutant, and immunolocalization using antibodies against PIP2;1 and PIP2;2 aquaporins revealed an increase in their abundance. Thus, the results obtained support the hypothesis about the importance of a sufficiently high ABA content in plants to maintain the abundance of aquaporins, hydraulic conductivity and the growth of barley plants.

Evaluation of functional plant growth-promoting activities of culturable rhizobacteria associated to tunicate maize (Zea mays var. tunicata A. St. Hil), a Mexican exotic landrace grown in traditional agroecosystems.

Tunicate maize (Zea mays var. tunicata A. St. Hil) is a landrace that constitutes a fundamental aspect of the socio-cultural identity of Ixtenco, Tlaxcala (Mexico) and represents an exotic phenotype whose kernels are enclosed in leaflike glumes. Despite multiple studies conducted worldwide on plant growth-promoting-rhizobacteria (PGPR) in commercial maize varieties grown under monoculture systems, very little is known about bacteria inhabiting native maize landraces in agroecosystems, but for tunicate maize such knowledge is non-existent. This research described and profiled functional groups of culturable rhizobacteria from tunicate maize at two phenological stages (tasseling and maturity/senescence) in a polyculture system, highlighting potential PGPR for biotechnological purposes. Ninety-five rhizobacteria were isolated and molecularly identified, and their physiological activities such as plant growth promotion, production of exogenous lytic enzymes, and antagonism against fungal pathogens were determined. The culturable rhizobacterial community associated to tunicate maize comprised 42 genera, dominated by Bacillaceae, Comamonadaceae, Microbacteriaceae, Micrococcaceae, Oxalobacteraceae, Pseudomonadaceae, and Rhizobaceae families. At tasseling stage, the identified bacteria corresponded to Arthrobacter, Priestia, Herbaspirillum, Pseudomonas, and Rhizobium, and exhibited redundant capabilities for stimulating plant growth and nutrition, and inhibiting fungal phytopathogens. At maturity/senescence stage, the main genera Arthrobacter and Microbacterium displayed lytic capabilities to support mineralization process. We recorded potential novel rhizosphere functional bacteria such as Rhizobium, Sphingobium, and Arthrobacter which are not previously described associated to maize landraces, as well as their bioprospection as PGPR detected at plant phenological stages poorly explored (like maturity/senescence). This taxonomic and functional diversity was attributed to the application of agricultural practices as well as the rhizosphere effect during specific phenological stages. Results described the diversity and functionality of culturable rhizosphere bacteria from tunicate maize in polyculture systems that allowed us the detection of potential rhizobacteria for further developing of biofertilizers and biocontrollers directed as biotechnology for sustainable agriculture, and for generating strategies for conservation of native plants and their microbial genetic resources.

Improving plant nutrition and growth through the use of minerals extracted from the sea on Aubergine and cucumber plants

Research objective: The aim of this research was to evaluate the stimulating potential of a product (FertilTomix) obtained by an innovative extraction process from seawater with the addition of silver, copper and zinc on aubergine and cucumber plants. In addition, it was assessed whether the product improves the nutritional quality of the fruit. Materials and Methods: The experiments, which started in May 2024, were conducted in the CREA-OF greenhouses in Pescia (Pt), on aubergine (Solanum melongena L.) and cucumber (Cucumis sativus). Plants were placed in pots of ø 14 cm, 30 plants per thesis, divided into three replications of 10 plants each. The experimental groups were: i) control group; ii) conmmercial biofertilizer; iii) FertilTomix; iv) FertilTomix with added silver, copper and zinc. On 10 September 2024, plant height (aubergine), length of the central branch (cucumber), number of leaves, leaf area, vegetative weight, root volume, number and weight of fruits were determined. The nutritional properties of the fruits were also assessed, for aubergine (iron, calcium, sodium, potassium, phosphorus, zinc, riboflavin thiamnine, vitamin C, niacin, vitamin B6, folate) and for cucumber (potassium, phosphorus, calcium, magnesium, sodium, iron, pantothenic acid, pyridoxine, zinc, manganese, vitamin C, niacin, riboflavin, vitamin E, thiamine, vitamin K, folate). Results and Discussion: The experiment showed that the use of FertilTomix, can significantly increase the height, number of leaves, vegetative and root growth, and leaf area of aubergine and cucumber plants. The product FertilTomix with added silver, copper and zinc worked better than as such, stimulating plant growth more. The trial also showed an increase in the number and weight of fruits in both aubergine and cucumber, in the theses treated with FertilTomix compared to the control and the commercial control with algae. The leaves also appeared larger and more intensely green in the theses treated with minerals extracted from the sea. The analysis of the mineral and vitamin content of the fruits showed a significant increase in minerals and vitamins in the fruits treated with FertilTomix for most of the analysed parameters, to a greater extent with FertilTomix with added silver, copper and zinc Conclusions: Various extracts obtained from seawater using an innovative mineral process were found to significantly increase plant growth. The test also showed an increase in the mineral and vitamin content of the fruit, probably influenced by the increased presence of bacteria in the soil, in the theses treated with marine extracts, as demonstrated in other tests with the same product. As well as for those wishing to reduce the use of industrial fertilisers, the results obtained are particularly interesting for those growing in arid environments or those without drinking water

Profiling the biocontrol agents, nitrogen-fixing bacteria, and indole acetic acid-producing bacteria in anthill soil

Due to the adverse ecological impacts of prolonged and excessive use of agrochemicals, many researchers have called for the adoption of eco-friendly materials in farming. Consequently, the aim of this study is to profile the biocontrol agents, nitrogen-fixing, and indole-acetic-acid-producing bacteria present in anthill soil. Anthill soils and adjacent soils were collected, and their physicochemical properties were analysed using standard analytical methods. Viable bacteria were isolated and screened for plant growth-promoting (PGP) activity using standard biochemical, morphological, and bacteriological methods. The PGP capacity of the isolates was evaluated using standard protocol for nitrogen fixation and indole-acetic-acid production, while antagonistic effect against plant pathogens was evaluated using the disk diffusion assay. Results revealed that Pseudomonas aeruginosa, Klebsiella pneumoniae, and Bacillus sp. isolated from the anthill soil demonstrated PGP characteristics including IAA production and nitrogen fixation. Bacillus sp. exhibited zones of clearance with values of 20.00 ± 1.50 mm, 20.00 ± 1.75 mm, 17.00 ± 1.33 mm, and 17.00 ± 1.33 mm against Aspergillus niger, Trichoderma sp., Penicillium sp., and Fusarium sp., respectively. This study demonstrated that anthill soils contain beneficial microbes with the potential to stimulate plant growth and suppress soil-borne plant pathogens.

Isolation and molecular identification for the first time in Iraq of sulfur-oxidizing bacteria and testing their possession of the plant growth stimulating criteria

Isolation and molecular identification for the first time in Iraq of sulfur-oxidizing bacteria and testing their possession of the plant growth stimulating criteria

Encapsulation of Bacillus subtilis in Electrospun Poly(3-hydroxybutyrate) Fibers Coated with Cellulose Derivatives for Sustainable Agricultural Applications.

One of the latest trends in sustainable agriculture is the use of beneficial microorganisms to stimulate plant growth and biologically control phytopathogens. Bacillus subtilis, a Gram-positive soil bacterium, is recognized for its valuable properties in various biotechnological and agricultural applications. This study presents, for the first time, the successful encapsulation of B. subtilis within electrospun poly(3-hydroxybutyrate) (PHB) fibers, which are dip-coated with cellulose derivatives. In that way, the obtained fibrous biohybrid materials actively ensure the viability of the encapsulated biocontrol agent during storage and promote its normal growth when exposed to moisture. Aqueous solutions of the cellulose derivatives-sodium carboxymethyl cellulose and 2-hydroxyethyl cellulose, were used to dip-coat the electrospun PHB fibers. The study examined the effects of the type and molecular weight of these cellulose derivatives on film formation, mechanical properties, bacterial encapsulation, and growth. Scanning electron microscopy (SEM) was utilized to observe the morphology of the biohybrid materials and the encapsulated B. subtilis. Additionally, ATR-FTIR spectroscopy confirmed the surface chemical composition of the biohybrid materials and verified the successful coating of PHB fibers. Mechanical testing revealed that the coating enhanced the mechanical properties of the fibrous materials and depends on the molecular weight of the used cellulose derivatives. Viability tests demonstrated that the encapsulated B. subtilis exhibited normal growth from the prepared materials. These findings suggest that the developed fibrous biohybrid materials hold significant promise as biocontrol formulations for plant protection and growth promotion in sustainable agriculture.

The use of mineral dynamised high dilutions for natural plant biostimulation; effects on plant growth, crop production, fruit quality, pest and disease incidence in agroecological strawberry cultivation

ABSTRACT Strawberries (Fragaria x ananassa) are one of the most important fruit crops worldwide. Most of the strawberries that are produced today rely on the use of pesticides and fungicides, leading the crop to be listed as one of the most contaminated by contentious inputs. Plant biostimulants are used as a plant health strategy focused on stimulating plant growth and development with a low residual impact. The objective of this study was to assess the plant biostimulation effects of strawberry plants treated with mineral dynamised high dilutions (DHDs): Sulphur 12CH, Phosphorus 12CH, Kali carbonicun 12CH, Calcarea carbonica 12CH, Silicea terra 12CH, Natrum muriaticum 12CH and Mercurius solubilis 12 CH, distilled water 12CH and distilled water (control). The experiment was undertaken under greenhouse conditions at the University of Santa Catarina State (UDESC), in Lages, Santa Catarina (SC), Brazil in 2019 and was repeated in 2021 at the Federal University of Santa Catarina (UFSC), in Curitibanos, SC. The experiment used a randomised block design, following double-blind treatment application. Data were analysed by ANOVA and when significant (p ≤ 0.05) by Dunnett’s test. The results showed that plants treated with DHDs of Sulphur 12CH, Phosphorus 12CH and Kali carbonicum 12CH increased plant growth and crop yield and were less affected by leaf spot disease (Mycosphaerella fragariae). Plants treated with Silicea terra 12CH, or with Calcarea carbonica 12CH showed increased development of the root system. The results obtained suggested that mineral DHDs could be used as plant biostimulants to support agroecological strawberry production.

Assessment of rice rhizosphere-isolated bacteria for their ability to stimulate plant growth and their antagonistic effects against Xanthomonas arboricola pv. juglandis.

The online version contains supplementary material available at 10.1007/s13205-024-04077-5.

Phase Transfer Catalysis: New Technology to Boost Organic Farming

Introduction of Phase Transfer Catalysis (PTC) technology, which was developed in the 1970s has revolutionised the dyes and pharmaceutical industries in many ways. PTC is a process that facilitates the organic compounds to move from one phase to another phase, without any change in the chemical qualities. Application of this technology was explored in the 1980s for agriculture, by using different plant extracts as PT catalysts. The objective was to facilitate increased absorption of nutrients by plants, by stimulating plant growth and easy availability of nutrients in the soil. Introduction of nano-carbon materials with nutrients and herbal growth stimulants could further support the crop growth by facilitating increased uptake of nutrients, apart from enabling the plants to develop resilience to harsh environmental conditions, resulting in higher crop yields. Some organic bio-stimulants developed recently by Snehasrusthi Group in India have been very successful in improving the growth, yield and quality of several seasonal and perennial crops in India. These bio-stimulants have excellent potential to boost organic agricultural production and income of farmers in the future.

Comparative Study of Bacillus-Based Plant Biofertilizers: A Proposed Index.

The market for bacteria as agricultural biofertilizers is growing rapidly, offering plant-growth stimulants; biofungicides; and, more recently, protectors against extreme environmental factors, such as drought. This abundance makes it challenging for the end user to decide on the product to use. In this work, we describe the isolation of a strain of Bacillus velezensis (belonging to the operational group Bacillus amyloliquefaciens) for use as a plant-growth-promoting rhizobacterium, a biofungicide, and a protector against drought. To compare its effectiveness with other commercial strains of the same operational group, Bacillus amyloliquefaciens, we analyzed its ability to promote the growth of pepper plants and protect them against drought, as well as its fungicidal activity through antibiosis and antagonism tests, its ability to solubilize potassium and phosphates, and its ability to produce siderophores. Finally, we used a probit function, a type of regression analysis used to model the outcomes of analyses, to quantify the biostimulatory effectiveness of the different plant-growth-promoting rhizobacteria, developing what we have called the Agricultural Protection Against Stress Index, which allowed us to numerically compare the four commercial strains of the operational group Bacillus amyloliquefaciens, based on a Delphi method-a type of regression analysis that can be used to model a cumulative normal distribution-and integrate the results from our panel of tests into a single value.

Microbial Utilization to Nurture Robust Agroecosystems for Food Security

In the context of anthropogenic evolution, various sectors have been exploited to satisfy human needs and demands, often pushing them to the brink of deterioration and destruction. One such sector is agrochemicals, which have been increasingly employed to achieve higher yields and bridge the gap between food supply and demand. However, extensive and prolonged use of chemical fertilizers most often degrades soil structure over time, resulting in reduced yields and consequently further exacerbating the disparity between supply and demand. To address these challenges and ensure sustainable agricultural production, utilization of microorganisms offers promising solutions. Hence, microorganisms, particularly effective microorganisms (EMs) and plant growth-promoting microbes (PGPMs), are pivotal in agricultural biomes. They enhance crop yields through active contribution to crucial biological processes like nitrogen fixation and phytohormone synthesis, making vital nutrients soluble and acting as natural enemies against pests and pathogens. Microbes directly enhance soil vigor and stimulate plant growth via the exudation of bioactive compounds. The utilization of EMs and PGPMs reduces the need for chemical inputs, leading to lower costs and reduced environmental pollutants. Furthermore, beneficial soil microflora produces growth-related metabolites and phytohormones that augment plant growth and support stress resilience. Microbes also help plants tolerate various abiotic stresses, including metal stress, salt stress, and drought stress, through various mechanisms. Understanding the interactions and activities of microorganisms provides valuable insights into their potential use to manage stress in plants. Thus, by leveraging the full potential of microorganisms, we can develop healthier agroecosystems that contribute sustainably to meet the growing global food demands.

The Potential of Deleterious rhizobacteria to Control Primary Weed <i>Echinochloa </i>sp. on Rice

Deleterious rhizobacteria (DRB) is one of the rhizobacteria that can be used as a bioherbicide and can stimulate plant growth. The objectives that can be obtained from this study are to determine the potential of DRB on the growth of weeds Echinochloa crusgalli and Echinochloa colona on rice. Variables observed in this study were identification of secondary metabolites, measurement of weed sprouts, percentage effectiveness of bacterial isolates against weed seeds, normal sprouts, abnormal sprouts, fresh seeds that did not grow and dead seeds. The aim of this study is to explore biological agents that can be used to control the main weeds of rice crops. This candidate could be a recommendation for environmentally friendly controls. Exploration of the DRB group was obtained by collecting soil samples around the roots of rice crops. Then isolate it, identify as morphologically and physiologically, and test it in vitro studies. The results showed that DRB had the potential to control weed growth and could stimulate the growth of rice. The application of PFA and PFB isolates had a significant effect on inhibiting the length of weed roots and buds, the average percentage of control effectiveness > 80-90%. Novelty in this study could be found as candidate groups of DRB bacteria with specific locations to control the weed Echinochloa sp. on rice crops. For society, this research could be an alternative to reduce dependence on synthetic herbicides . DRB has the potential to be formulated into a bioherbicide to control weeds.

Influence of Plant Spacing and Bio-fertilizers on Yield and Yield Attributing Characters of Rain-fed Soybean at Damazin in Blue Nile State, Sudan

This study had the objective of evaluating the effect of biofertilizers on the performance of soybean plants under different planting spacing. It was conducted during the summer seasons of 2018 and 2019at one site at Demonstration Farm of Damazin Agricultural Research Station, Sudan. The different plant spacing designated as D1, D2, and D3 (5, 10, and 15 cm between plants) under three types of bio-fertilizers as Rhizobacteria (B1), Azotobacter (B2), Bacillus (B3) and control (B0). The experiment was laid out in Randomized Complete Block design (RCBD) with three replications as split-plots trail. The result revealed that the improvement due to the application of fertilizers with wider, spacing D3 stimulated plant growth and caused an increase in dry matter accumulation and high leaf area and gave the higher number of pods and seeds/pod, particularly at inoculation with B1 and B2 bacteria. While sowing seeds inoculated with B1or B2 under closer spacing resulted in higher seed yield per unit area. To achieve optimum results in soybean variety Sudan 1, the crop may be sown in plant spacing of 10cm with inoculation seeds with B1or B2 to achieve a high plant population per unit area to obtain higher seed yield.