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Bacterial endophytes are well known inhabitants of living plant system and perform important assignments in maintaining plant growth and health. Currently, limited reports are available on the endophytes of pearl millet (Pennisetum glaucum) reflecting antagonistic and plant growth promoting (PGP) attributes. Therefore, the major objectives of current investigation were to identify antagonistic strains of endophytic Bacillus from pearl millet and further illustrate their PGP capabilities. In this study, 19 endophytic Bacillus strains (EPP5,

Spent mushroom substrate (SMS), a major byproduct of the mushroom industry, is a lignocellulosic biomass, which contains approximately 57-74.3% of holocellulose fraction. This study was aimed at utilizing SMS of Pleurotus florida for recovery of lignocellulolytic enzymes and sugars and also as a substrate for production of cellulolytic enzymes using different isolates of Trichoderma and Aspergillus under solid-state fermentation (SSF). SMS of P.florida extracts contained significant amounts of laccase (3,015.8 ± 29.5 U/g SMS) and xylanase (1,187.9 ± 12 U/g SMS) activity. Crystallinity pattern and chemical changes in SMS revealed that SMS had a lower crystallinity index (34.2%) as compared with the raw biomass (37.8%), which, in turn, helps in enhancing the accessibility of cellulolytic enzymes to holocellulose. Among the isolates, Trichoderma longibrachiatum A-01 showed maximum activity of endoglucanase (220.4 ± 5.9 U/mg), exoglucanase (78.5 ± 3.2 U/mg) and xylanase (1,550.4 ± 11.6 U/mg) while Aspergillus aculeatus C-08 showed maximum activity of cellobiase (113.9 ± 3.9 U/mg). Extraction with sodium citrate buffer (pH 4.8) showed maximum cellulolytic enzyme activity as compared with other solvents tested. Partial purification of endoglucanase, exoglucanase, xylanase, and cellobiase resulted in 56.3% (1,112.5 U/mg), 48.4% (212.5 U/mg), 44%(4,492.3 U/mg), and 62% (705.0 U/mg) yield with an increase by 5.2-, 4.5-, 4.1-, and 5.0-fold as compared with crude extract. The results reveal that SMS from P. florida could be a potential and cost-effective substrate for production of cellulolytic enzymes from T. longibrachiatum A-01 and A. aculeatus C-08. K E Y W O R D Slignocellulolytic enzymes, Pleurotus florida, solid-state fermentation, spent mushroom substrate

The aim of present study was to decipher the effect of salinity stress on growth and antagonistic potential of Trichoderma and Hypocrea isolates against tomato root rot pathogen (Rhizoctonia solani AG-4) under saline soil conditions. In vitro salinity assays, dual plate confrontation, and volatile metabolite assays were employed to establish the antagonistic potential of Trichoderma and Hypocrea isolates against R. solani AG-4 under varied salt gradients. Potential Trichoderma and Hypocrea isolates were evaluated against tomato root rot disease in greenhouse conditions under salt stress condition. Polymerase chain reaction (PCR) assay was performed to confirm the presence of endochitinase gene in salt-tolerant antagonists. Enzyme and biochemical assays were conducted to define the role of compatible solutes and defense-related enzymes in controlling tomato root rot under saline soil conditions. Trichoderma and Hypocrea isolates were capable to grow and sporulate up to 250 mM NaCl and also showed strong antagonism against R. solani. Enzymatic estimation of hydrolytic enzymes and amplification of endochitinase gene suggested that the test isolates are potent antagonistic agents. Under greenhouse evaluation, Trichoderma and Hypocrea fortified tomato plants showed significant reduction in tomato root rot disease in saline soils over untreated control. Significant increase in total phenol, polyphenol oxidase, peroxidase, β-1,3-glucanase, phenylalanine lyase, chitinase, proline, reducing sugar, and total soluble sugar displayed direct association with salt stress tolerance. Application of salt-tolerant Trichoderma and Hypocrea isolates emerged as a simple, safe, and cheap method for the biological management of tomato root rot under saline condition.