Figure - available via license: Creative Commons Attribution 4.0 International
Content may be subject to copyright.
Miscellaneous traits and activities related to PGPR of the selected P. taeotroles ULE-PH5 and Pseudomonas sp. ULE-PH6 strains. Miscellaneous Traits Related to PGPR P. taetrolens ULE-PH5 Pseudomonas sp. ULE-PH6
Source publication
Most of the phosphorus incorporated into agricultural soils through the use of fertilizers precipitates in the form of insoluble salts that are incapable of being used by plants. This insoluble phosphorus present in large quantities in soil forms the well-known “phosphorus legacy”. The solubilization of this “phosphorus legacy” has become a goal of...
Contexts in source publication
Context 1
... study was conducted to test various traits of interest associated with PGPR to stimulate plant growth (Table 3). Both strains exhibited clear siderophore production in solid media. ...Context 2
... both strains were able to produce 3-indoleacetic acid (IAA), although strain ULE-PH5 exhibited a synthesis capacity of 59.29 µg/mL, practically double that detected in the ULE-PH6 strain (30.69 µg/mL). The ability to solubilize Zn was not detected in either of the two strains, whereas both strains were able to solubilize K (Table 3). Although both strains were selected for their ability to solubilize inorganic phosphate in liquid medium, we also tested their ability to solubilize P associated with organic matter. ...Context 3
... strains exhibited a strong solubilization capability of phytate in solid media (Table 1). Accordingly, high activities of phytate degradation in liquid medium of 40.25 ± 1.71 mU/mL for ULE-PH5 and 43.38 ± 2.75 for ULE-PH6 were detected (Table 3). ...Context 4
... activities were detected in the ULE-PH5 and ULE-PH6 strains. The levels of extracellular acidic phosphatases were considerably higher than the detected levels of extracellular alkaline phosphatases (Table 3). Acidic and alkaline phosphatases were also detected intracellularly, although their levels were, in all cases, lower than those detected outside the cell. ...Similar publications
Phosphorus (P) is crucial for plant growth and development, it is a macroelement that is required for plants to function physiologically. Even though there are a lot of P-containing organic and inorganic molecules in soil, most of them are inert, making them unavailable to plants. Phosphorus (P) deficiency is widely acknowledged as a critical const...
Citations
... In these products, the most abundant bacteria were Pseudomonas taetrolens and Serratia marcescens, 33% each. P. taetrolens was selected as a plant growth-promoting rhizobacterium that is able to significantly increase phosphate uptake and phosphorus accumulation in aboveground parts (stems, petioles, and leaves) [46]. S. marcescens is a bacterium typically found on pepper fruits; the bacterium causes soft rot disease on peppers and has a devastating effect on the crop, and it is a disease of increasing importance worldwide causing major economic losses [47]. ...
This study aimed to evaluate the effect of sous vide heat treatment and different packaging methods on the microbiological quality of red peppers (Capsicum annuum L.) during their refrigerated storage. Peppers of the Roberta variety were used in the study. The heat treatment of the peppers was carried out under vacuum conditions for all the packaging methods. ATM (unaltered gas atmosphere) and MAP (modified atmosphere packaging) products were repackaged under aseptic conditions into a suitable gaseous atmosphere after heat treatment and cooling into an unaltered atmosphere (ATM), and into a modified atmosphere (MAP: 30% CO2, 70% N2). The sous vide thermal treatment was performed in three variations: 30 min/60 °C, 15 min/70 °C, and 8 min/80 °C. The peppers were stored at 3 ± 1 °C until the bacterial count first exceeded 4 log CFU/g, but no longer than 24 days. The pH, TVC, Enterobacteriaceae count, and microscopic filamentous fungi count were determined in the products. A qualitative analysis of microbial isolates was also carried out using MALDI-TOF mass spectrometry. Sous vide heat treatment reduced the number of TVC (total viable count) (<2 to 2.35 log CFU/g), Enterobacteriaceae (<2 log CFU/g), and the number of microscopic filamentous fungi (<2 log CFU/g) compared with control (TVC 3.54–3.86 log CFU/g). The use of heat treatment combined with the packaging of culinary products effectively extends the shelf life of sous vide peppers, from 3 to 6 days for raw peppers to 15–24 days for sous vide peppers depending on the heat treatment and packaging method. All the packaging methods allowed the product to remain microbiologically safe (TVC below 4 log CFU/g) for 24 days for 30 min/60 °C and 15 min/70 °C treatments, and VAC packaging for 8 min/80 °C treatments. Bacterial identification by MALDI-TOF MS revealed that the predominant families were Pseudomonadaceae, Yersiniaceae, and Staphylococcaceae. Depending on the method of sous vide thermal treatment, it showed differences in the percentage of bacterial families in the culinary products. The proportions in the proportion of Gram+ and Gram- bacteria also changed. The use of sous vide processing in combination with appropriate packaging methods can significantly extend the shelf life of products obtained from peppers.
... As an important plant to resist desertification, it can grow in severely desertified soil, thanks to its rapid growth and well-developed root system. Through previous rhizosphere metagenomic studies [4,5], we speculated that in hotspots of microbial activity, rhizosphere microorganisms play an indispensable role in the colonization process of pioneer plants. Plant growth-promoting rhizobacteria (PGPR) can promote plant growth through a variety of mechanisms, including increasing the absorption of nutrient uptake [5], the production of plant hormones [6], resistance to biotic and abiotic stress, and the promotion of improvement of the rhizosphere environment [7]. ...
... Through previous rhizosphere metagenomic studies [4,5], we speculated that in hotspots of microbial activity, rhizosphere microorganisms play an indispensable role in the colonization process of pioneer plants. Plant growth-promoting rhizobacteria (PGPR) can promote plant growth through a variety of mechanisms, including increasing the absorption of nutrient uptake [5], the production of plant hormones [6], resistance to biotic and abiotic stress, and the promotion of improvement of the rhizosphere environment [7]. However, for plants in plateau and poor-soil areas, limited nutrients, extreme climate, and high altitude will limit the effects of these mechanisms. ...
Plant growth-promoting rhizobacteria (PGPR) are beneficial bacteria residing in the rhizosphere and are capable of enhancing plant growth through various mechanisms. Streptomyces sp. GD-4 is a plant growth-promoting bacterium isolated from the rhizosphere soil of Leymus secalinus. To further elucidate the molecular mechanisms underlying the beneficial effects of the strain on plant growth, we evaluated the growth-promoting effects of Streptomyces sp. GD-4 on forage grasses and conducted comprehensive genome mining and comparative genomic analysis of the strain. Strain GD-4 effectively colonized the rhizosphere of three forages and significantly promoted the growth of both plant roots and leaves. Genome sequence functional annotation of GD-4 revealed lots of genes associated with nitrogen, phosphorus, and sulfur metabolism. Additionally, genes potentially involved in plant growth promotion such as indole-3-acetic acid (IAA) biosynthesis, trehalose production, siderophore production, and phosphate solubilization were annotated. Whole-genome analysis revealed that GD-4 may possess molecular mechanisms involved in soil nutrient cycling in rhizosphere soil and plant growth promotion. The bacteria also possess genes associated with adaptability to abiotic stress conditions, further supporting the ability of Streptomyces sp. GD-4 to colonize nutrient-poor soils. These findings provide a foundation for further research into soil remediation technologies in plateau regions.
... Phosphorus and potassium are essential nutrients for plants [59], and the deficiency of phosphorus and potassium will reduce plant growth. However, most of the phosphorus and potassium in the soil is in the form of insoluble phosphorus and potassium, which cannot be directly absorbed by plants [60,61]. Thus, most crops require applications of phosphorus and potassium fertilizers to promote crop growth and improve crop quality and yield. ...
Root-knot nematodes are the major diseases in protected cultivation around the world. Bio-organic fertilizer has become a research hotspot, with a variety of microorganisms that control various vegetable soil-borne diseases. This study screened nematocidal microorganisms from fresh vermicompost, explored the inhibitory substances produced by biocontrol agents, and evaluated their potential biocontrol ability in the pot and field under greenhouse conditions. The highly effective antagonistic microbes of Meloidogyne incognita (M. incognita) were screened. Strains YL1 and YL31 were identified as Peribacillus frigoritolerans, and strain YL6 was identified as Lysinibacillus fusiformis. The three strains all produced chitinase and protease, which prevented the normal development of eggs and the second-stage juveniles (J2) by destroying their appearance. The three strains all improved potassium-dissolving ability, and the strains YL1 and YL6 also enhanced phosphorus-dissolving ability. Pot experiments showed that tomato root knots were reduced, and plant growth improved. Field tests showed that the root-knot index and nematode population were reduced significantly, and cucumber growth and yield were enhanced. Strain YL1 had the best control effect with 70.6%, and the yield increased by 14.9% compared with the control. Overall, this study showed the ability of antagonistic bacteria YL1, YL6, and YL31 to control root-knot nematodes, and these antagonistic bacteria could be developed as biocontrol agents for sustainable agriculture.
: Phytic acid is a prevalent anti-nutrient in human and animal diets, neutralized effectively by the enzyme phytase. This enzyme, extensively used in the food industry and livestock production, was the focus of our study to identify phytase-producing fungal species among contaminants in ultra-refined white cheeses. We evaluated the enzymatic activity of each isolate in phytase screening medium (PSM) and Luria bertani Broth (LB) media, determining optimal production conditions such as temperature and pH for the isolate with the highest activity. Initial screening from 110 mold isolates, representing 10 different species, identified 28 isolates across 6 species capable of producing phytase. These included Aspergillus niger, Aspergillus oryzae, Penicillium commune, Penicillium chrysogenum, Paecilomyces variotii, and Cladosporium cladosporioides, discernible by halo zones around their colonies. The highest activity levels were recorded for P. commune (133.76 U/mL) and P. variotii (216.7 U/mL) in PSM and LB media, respectively. Remarkably, this study is the first to document phytase production by P. variotii, showcasing the highest activity among the isolates and presenting a new opportunity for industrial phytase production. The enzyme isolated from P. variotii demonstrated stability and optimum activity at temperatures from 20°C to 70°C and pH 4.0 to 7.0, peaking at 50°C and pH 6.0. Its unique properties suggest significant potential for industrial applications, positioning it as a novel candidate for further exploration in industrial phytase production.
