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Endophytes are one of the symbiotic associations which can be successfully utilized to mitigate negative effects of abiotic stress in agricultural crops. Habitat adapted symbiotic fungal endophytes are known to impart heavy metal stress tolerance in host plants. Besides, endophytic fungi secrete secondary metabolites and enhance the plant's ability to tolerate stressful conditions. Therefore, this study was aimed at evaluating fungal endophytes of arsenic stress adapted plants for their arsenic tolerance potential. Present study yielded 83 arsenic tolerant fungal endophytes from the plants grown in arsenic-contaminated areas of Karnataka. These isolates were screened for arsenic tolerance at different arsenic (Sodium arsenite) concentrations (100 ppm to 2000 ppm). Among the isolates, eight endophytes (S1P1R1, S3P1S1, S3P1S3, S4P2L2, S5P1S1, S6P1S3, S8P1L4 and S10P1L1) were found efficiently enduring metal stress up to 2000 ppm with tolerance index >0.5. These isolates were further re-evaluated for arsenic tolerance in biomass assay. Significantly higher biomass was achieved in all eight endophytes at 100 PPM arsenic concentration compared to non arsenic control. However, fungal biomass relatively reduced with subsequent increase in arsenic concentration from 250 ppm to 2000 ppm. Further, these endophytes were evaluated for their ability to alleviate arsenic stress and growth promotion of rice seedlings under in vitro arsenic stress condition. Rice seedlings inoculated with fungal endophytes showed significant increase in shoot length under arsenic stress compared to control. Among eight endophytes, the isolate S3P1S1 significantly enhanced shoot and root length of rice. Therefore, data obtained in the present study revealed that the fungal endophyte, isolated from arsenic adapted plant has ability to mitigate arsenic stress and improve the rice growth under arsenic condition. [ABSTRACT FROM AUTHOR]

Endophytes are one of the symbiotic associations which can be successfully utilized to mitigate negative effects of abiotic stress in agricultural crops. Habitat adapted symbiotic fungal endophytes are known to impart drought tolerance in host plants. This study aimed at evaluating fungal endophytes of drought adapted plants against drought stress in maize. Fungal endophytes were isolated from arid and semi-arid regions of Karnataka and screened for their ability to grow in matric modified media using Polyethylene glycol (PEG 8000). Out of 65 isolates, six isolates (P1R1, P4L5, P6R3, P6R4, P10R1 and P12R2) showed increased mycelial growth up to -10.31 MPa (30 % PEG). The six fungal endophytes were evaluated for their ability to alleviate drought stress and improve growth of maize seedlings at PEG induced drought stress under in vitro condition. Maize seedlings inoculated with fungal endophytes showed significant increase in shoot length under drought stress after 10 days compared to control. Among six endophytes, the isolate P10R1 significantly enhanced shoot and root length of maize. The fungus was identified as Alternaria burnsi by using ITS region sequences. This study revealed that the fungal endophyte, Alternaria burnsi isolated from drought adapted plant has ability to mitigate drought stress and improve the maize growth under drought condition. [ABSTRACT FROM AUTHOR]

Four plants with medicinal properties Carica papaya, Phyllanthus amarus, Tinospora cordifolia and Azadiracta indica were selected as a host plant for the isolation of endophytic fungi collected from Biligirirangana Hill, ranges from 11° 40' to 12° 09' North and 77° 05' to 77° 01' East, the southern part of Eastern Ghats Chamarajanagar District, Karnataka. The leaves of these plants revealed two, four, six and three isolates of endophytic fungi which belonged to the family Hypomycetes, Ascomycetes, Dothideomycetes, Coleomycetes respectively. One of the unidentified strain from each of the above four medicinal plant isolate was subjected to molecular analysis followed by 18SrRNA sequence, internal transcribed spacer regions and phylogenetic analysis. Based on the gene sequencing and phylogenetic tree the clusters species of the fungal isolate was found to be Stemphylium lycopersici, Epicoccum nigrum, Leptosphaerulina arachidicola and Phomopsis azadirachtae reported in this paper. [ABSTRACT FROM AUTHOR]

The diversity of fungal endophytes in Sorghum bicolor was investigated in samples collected from 10 different geographical regions of Karnataka state, India. A total of 360 endophytes were isolated from leaf, stem, and root tissues and were assigned to 26 fungal species based on morphology and molecular characterization using ITS sequences. All the endophytes belonged to the phylum Ascomycota. The diversity (Shannon H, 2.57; Simpson_1‐D, 0.92) and species richness (Margalef's, 4.68; Menhinick, 3.61) were found to be higher for the endophytes isolated from leaf tissues. The species evenness of the endophytic assemblage was strongly influenced by tissue type, followed by geographical location. The biocontrol potential of isolated endophytes was evaluated against economically destructive sorghum grain mould pathogens such as Fusarium thapsinum, Epicoccum sorghinum, Alternaria alternata, and Curvularia lunata using the dual culture method. Biocontrol potential was exhibited by 26 endophytic isolates, of which Trichoderma asperellum recorded broad‐spectrum activity against target pathogens, followed by E. nigrum and A. longipes. Most (82%) endophytes showed plant growth‐promoting traits. Biosynthesis of indole‐3‐acetic acid (IAA) was observed in 84% of isolates, and phosphate solubilization, siderophore production, and cellulase activity was observed in 69%, 23%, and 27% of isolates, respectively. Seeds treated with T. asperellum exhibited a significantly higher seed vigour index (2096), germination percentage (94%), and yield under greenhouse and field conditions. The results were substantiated by the confocal microscopy analysis, which clearly demonstrated the colonization of treated endophyte in root tissues. The present study reveals an ecofriendly approach to explore T. asperellum in sorghum disease management. [ABSTRACT FROM AUTHOR]

The objective of the present study was the bioprospection of bioactive compounds from endophytic Thielaviopsis basicola with therapeutic applications, isolated from Ximenia americana, Western Ghats of Karnataka, India. The fresh and healthy leaves and roots of Ximenia americana were collected from the forests of Western Ghats of Karnataka, India. The collected explants were submerged for the enumeration and purification of fungal endophytes by using selective, and different media. Isolated fungal endophytes were processed for the production, extraction, phytochemical analysis, purification and evaluation of bioactive compounds by referring standard protocols. At a glance, endophyte derived bioactive compounds were used in in-vitro antagonistic, antioxidant antiurolithisis, and anticancer activity. A total of 32 pure isolates were obtained, 8 morphologically distinct fungal endophytes were identified from 200 explants of X. americana. Endophytic Thielaviopsis basicola was a core candidate identified and cultivated in solid-state fermentation on corn bran under the dark condition at 25° ± 2° for 15 days. Obtained 5.30g of aqueous crude extract per 100g of cornmeal were processed for qualitative phytochemical analysis, in alkaloids, terpenoids, flavonoids, phenols, tannins, and glycosides were found. The aqueous crude extract showed 0.761g of phenol and 0.276g of flavonoids content. From these crude extract TbCC1 and TbCC2, two fractions were purified by column chromatography and spotted potent bioactive compounds on thin layer chromatography. The FTIR data of TbCC1 and TbCC2 showed different functional groups such as alcohol, phenols, alkanes, alkenes, aromatic, alkyl halides, amines, ether, and nitrile. The TbCC1 exhibited prominent antagonistic activity and MIC against Staphylococcus aureus (24mm with 100µg/mL) and Candida albicans (22mm with 75µg/mL) while TbCC2 exhibited against Salmonella typhi (22mm with 75µg/mL) and Aspergillus fumigatus (18mm with 75µg/mL). The TbCC1 showed potent antioxidant activity (86.24±0.35) with 5.26µg/mL of IC50 value as compared with TbCC2. The maximum antiurolithiasis activity showed with 100% concentration at the rate of 67.5±1.49 of aqueous crude extract. The Sulphorodamine B assay showed MCF7 human breast cancer cell line viability 98.39±0.0250 at 100µg concentration and 40.81±0.0470 at 500µg with an IC50 value of 459.60µg. This is the first innovative report of endophytic Thielaviopsis basicola for their phytochemicals detection and prominent in-vitro activities from the selected plants. [ABSTRACT FROM AUTHOR]