Plant growth-promoting endophytes (PGPE) are microorganisms which reside in plant tissues and are beneficial to the host in plant growth promotion and pathogen resistance. They are the eco-friendly and sustainable alternative to chemical fertilizers and pesticides. This study aimed to analyze the plant growth-promoting properties of the five endophytic fungal strains from the medicinal plant Aegle marmelos Corr. and evaluate their effects on Oryza sativa plants. Firstly, endophytes were isolated from the different parts of A. marmelos and identified by ITS sequencing. Phosphate solubilization ability was checked in Pikovskaya's agar medium, IAA secretion was measured by the Salkowski colourimetric method, and ACC deaminase activity was checked by Penrose's method. Four endophytic fungal strains with promising PGP activities were inoculated into rice seeds to check their growth promotion in rice. The strain Purpureocillium lilacinum (AMR2) enhanced the seed vigour of rice seeds and demonstrated excellent root colonization ability. Periconia byssoides (AML2) and Medicopsis romeroi (AMS3) were the most effective plant growth-promoting agents, leading to both crop yield improvement and enhanced plant morphological growth due to their great ability to solubilize inorganic phosphate, ACC deaminase activity and production of IAA and Gibberellin A3 (GA3). These endophytic strains could serve as microbial inoculants to enhance crop production, offering an eco-friendly alternative.

• Klíčová slova
• Periconia sp., ACC deaminase, Enzyme production, Gibberellin A3, IAA, Plant growth-promoting endophytes,
• Publikační typ
• časopisecké články MeSH

Nitrogen, phosphorus, and potassium are the three most essential micronutrients which play major roles in plant survivability by being a structural or non-structural component of the cell. Plants acquire these nutrients from soil in the fixed (NO3¯, NH4+) and solubilized forms (K+, H2PO4- and HPO42-). In soil, the fixed and solubilized forms of nutrients are unavailable or available in bare minimum amounts; therefore, agrochemicals were introduced. Agrochemicals, mined from the deposits or chemically prepared, have been widely used in the agricultural farms over the decades for the sake of higher production of the crops. The excessive use of agrochemicals has been found to be deleterious for humans, as well as the environment. In the environment, agrochemical usage resulted in soil acidification, disturbance of microbial ecology, and eutrophication of aquatic and terrestrial ecosystems. A solution to such devastating agro-input was found to be substituted by macronutrients-availing microbiomes. Macronutrients-availing microbiomes solubilize and fix the insoluble form of nutrients and convert them into soluble forms without causing any significant harm to the environment. Microbes convert the insoluble form to the soluble form of macronutrients (nitrogen, phosphorus, and potassium) through different mechanisms such as fixation, solubilization, and chelation. The microbiomes having capability of fixing and solubilizing nutrients contain some specific genes which have been reported in diverse microbial species surviving in different niches. In the present review, the biodiversity, mechanism of action, and genomics of different macronutrients-availing microbiomes are presented.

• Klíčová slova
• Availability, Biodiversity, Macronutrients, Nitrogen, Phosphorus, Potassium, Sustainability,
• Publikační typ
• časopisecké články MeSH
• přehledy MeSH

Endophytic microbes are plant-associated microorganisms that reside in the interior tissue of plants without causing damage to the host plant. Endophytic microbes can boost the availability of nutrient for plant by using a variety of mechanisms such as fixing nitrogen, solubilizing phosphorus, potassium, and zinc, and producing siderophores, ammonia, hydrogen cyanide, and phytohormones that help plant for growth and protection against various abiotic and biotic stresses. The microbial endophytes have attained the mechanism of producing various hydrolytic enzymes such as cellulase, pectinase, xylanase, amylase, gelatinase, and bioactive compounds for plant growth promotion and protection. The efficient plant growth promoting endophytic microbes could be used as an alternative of chemical fertilizers for agro-environmental sustainability. Endophytic microbes belong to different phyla including Euryarchaeota, Ascomycota, Basidiomycota, Mucoromycota, Firmicutes, Proteobacteria, and Actinobacteria. The most pre-dominant group of bacteria belongs to Proteobacteria including α-, β-, γ-, and δ-Proteobacteria. The least diversity of the endophytic microbes have been revealed from Bacteroidetes, Deinococcus-Thermus, and Acidobacteria. Among reported genera, Achromobacter, Burkholderia, Bacillus, Enterobacter, Herbaspirillum, Pseudomonas, Pantoea, Rhizobium, and Streptomyces were dominant in most host plants. The present review deals with plant endophytic diversity, mechanisms of plant growth promotion, protection, and their role for agro-environmental sustainability. In the future, application of endophytic microbes have potential role in enhancement of crop productivity and maintaining the soil health in sustainable manner.

• Klíčová slova
• Abiotic stress, Agricultural sustainability, Endophytes, Plant growth promotion,
• MeSH
• Ascomycota * MeSH
• Bacillus * MeSH
• Bacteria genetika   MeSH
• Basidiomycota * MeSH
• endofyty MeSH
• Publikační typ
• časopisecké články MeSH
• přehledy MeSH

Modern technologies can satisfy human needs only with the use of large quantities of fertilizers and pesticides that are harmful to the environment. For this reason, it is possible to develop new technologies for sustainable agriculture. The process could be carried out by using endophytic microorganisms with a (possible) positive effect on plant vitality. Bacterial endophytes have been reported as plant growth promoters in several kinds of plants under normal and stressful conditions. In this study, isolates of bacterial endophytes from the roots and leaves of Miscanthus giganteus plants were tested for the presence of plant growth-promoting properties and their ability to inhibit pathogens of fungal origin. Selected bacterial isolates were able to solubilize inorganic phosphorus, fix nitrogen, and produce phytohormones, 1-aminocyclopropane-1-carboxylic acid (ACC) deaminase, and siderophore. Leaf bacterial isolate Pantoea ananat is 50 OL 2 had high production of siderophores (zone ≥ 5 mm), and limited phytohormone production, and was the only one to show ACC deaminase activity. The root bacterial isolate of Pseudomonas libanensis 5 OK 7A showed the best results in phytohormone production (N6-(Δ2-isopentenyl)adenine and indole-3-acetic acid, 11.7 and 12.6 ng·mL-1, respectively). Four fungal cultures-Fusarium sporotrichioides DBM 4330, Sclerotinia sclerotiorum SS-1, Botrytis cinerea DS 90 and Sphaerodes fimicola DS 93-were used to test the antifungal activity of selected bacterial isolates. These fungal cultures represent pathogenic families, especially for crops. All selected root endophyte isolates inhibited the pathogenic growth of all tested fungi with inhibition percentages ranging from 30 to 60%. Antifungal activity was also tested in two forms of immobilization of selected bacterial isolates: one in agar and the other on dextrin-coated cellulose carriers. These results demonstrated that the endophytic Pseudomonas sp. could be used as biofertilizers for crops.

• Klíčová slova
• ACC deaminase, phosphorus solubilization, phytohormone, siderophore,
• Publikační typ
• časopisecké články MeSH

Endophytic fungal communities have attracted a great attention to chemists, ecologists, and microbiologists as a treasure trove of biological resource. Endophytic fungi play incredible roles in the ecosystem including abiotic and biotic stress tolerance, eco-adaptation, enhancing growth and development, and maintaining the health of their host. In recent times, endophytic fungi have drawn a special focus owing to their indispensable diversity, unique distribution, and unparalleled metabolic pathways. The endophytic fungal communities belong to three phyla, namely Mucoromycota, Basidiomycota, and Ascomycota with seven predominant classes Agaricomycetes, Dothideomycetes, Eurotiomycetes, Mortierellomycotina, Mucoromycotina, Saccharomycetes, and Sordariomycetes. In a review of a huge number of research finding, it was found that endophytic fungal communities of genera Aspergillus, Chaetomium, Fusarium, Gaeumannomyces, Metarhizium, Microsphaeropsis, Paecilomyces, Penicillium, Piriformospora, Talaromyces, Trichoderma, Verticillium, and Xylaria have been sorted out and well characterized for diverse biotechnological applications for future development. Furthermore, these communities are remarkable source of novel bioactive compounds with amazing biological activity for use in agriculture, food, and pharmaceutical industry. Endophytes are endowed with a broad range of structurally unique bioactive natural products, including alkaloids, benzopyranones, chinones, flavonoids, phenolic acids, and quinines. Subsequently, there is still an excellent opportunity to explore novel compounds from endophytic fungi among numerous plants inhabiting different niches. Furthermore, high-throughput sequencing could be a tool to study interaction between plants and endophytic fungi which may provide further opportunities to reveal unknown functions of endophytic fungal communities. The present review deals with the biodiversity of endophytic fungal communities and their biotechnological implications for agro-environmental sustainability.

• MeSH
• Ascomycota * metabolismus   MeSH
• biodiverzita MeSH
• ekosystém MeSH
• endofyty MeSH
• houby metabolismus   MeSH
• mykobiom * MeSH
• Publikační typ
• časopisecké články MeSH
• přehledy MeSH

The endophytic actinobacteria associated with Artemisia herba-alba (synonym: Seriphidium herba-alba) are highly diverse. This study aimed to illustrate the extent of their differences from the free-living actinobacteria in the surrounding environment. A selection of eighteen actinobacteria inhabiting A. herba-alba were compared with twenty and ten actinobatceria isolates from the surrounding desert and groundwater, respectively, representing six genera. Antagonistic and enzymatic activities, plant growth-promoting traits, and the occurrence of biosynthetic genes were compared among the isolates. Data were analyzed statistically using principal component analysis (PCA) and were visualized using heat map. Endophytic strains showed higher antimicrobial activity and production of plant growth promoters compared to desert and groundwater strains. Polyketide synthase and non-ribosomal peptide synthetase gene clusters were detected at higher frequencies in the endophytic strains (8 and 11 strains, respectively) than the desert strains (1 and 2 strains, respectively). In contrast, both gene clusters were not detected in the groundwater strains. The PCA revealed unique metabolic characteristics of the endophytes. The heatmap clustered the endophytic strains apart from the free-living strains, indicating distinctive qualitative and quantitative bioactivities. Analysis of 16S rRNA genes confirmed the chemotaxonomic identity of all but two strains, with > 94.5% similarity. Six endophytes displayed < 99.5% similarity with their closest type strains, which might indicate species novelty. This study provides an evidence of functional differences and possible species novelty of the endophytic actinobacteria inhabiting A. herba-alba, compared with the free-living species.

• MeSH
• Actinobacteria * genetika   MeSH
• endofyty genetika   MeSH
• fylogeneze MeSH
• pelyněk * MeSH
• RNA ribozomální 16S genetika   MeSH
• Publikační typ
• časopisecké články MeSH
• Názvy látek
• RNA ribozomální 16S MeSH

Climate change impacts environmental conditions that affect photosynthesis. This review examines the effect of combinations of elevated atmospheric CO2, long photoperiods, and/or unfavorable nitrogen supply. Under moderate stress, perturbed plant source-sink ratio and redox state can be rebalanced but may result in reduced foliar protein content in C3 plants and a higher carbon-to-nitrogen ratio of plant biomass. More severe environmental conditions can trigger pronounced photosynthetic downregulation and impair growth. We comprehensively evaluate available evidence that microbial partners may be able to support plant productivity under challenging environmental conditions by providing (1) nutrients, (2) an additional carbohydrate sink, and (3) regulators of plant metabolism, especially plant redox state. In evaluating the latter mechanism, we note parallels to metabolic control in photosymbioses and microbial regulation of human redox biology.

• Klíčová slova
• carbohydrate, electron transport, homeostasis, nitrogen, reactive oxygen species, redox signaling,
• Publikační typ
• časopisecké články MeSH
• přehledy MeSH