Bioformulation development via valorizing silica-rich spent mushroom substrate with Trichoderma asperellum for plant nutrient and disease management

Abstract

The present investigation was performed to valorize paddy straw (PS) based silica (Si) rich Spent Mushroom Substrate (SMS) of Pleurotus ostreatus for Plant Nutrient and Disease Management in wilt (caused by F. oxysporum f. sp. lycopersici) susceptible tomato plant F1 Hybrid King 180. Raw PS and SMS generated by P. ostreatus cultivated on PS only, and PS amended with 5% soybean cake (SC) were bio-fortified with Trichoderma asperellum (TA). SMS (PS+ 5% SC) was found supporting the growth of T. asperellum to an extent of 12.37 × 10¹³ conidia/g substrate. GC-MS analysis of SMS detected several bioactive metabolites like Palmitic acid, Oleic acid, Methyl linoleate, Stigmasterol, etc., known for plant health management. Bioformulations were developed employing Press Mud (PM) and Talcum Powder (TP) as carrier materials. Among the different bioformulations tested in pots study; SMS (PS+ 5% SC) SiTAPM, collectively named as TF-I, provided improved levels of morpho-biochemical and nutritional parameters, i.e., Plant Biomass (2.27 folds), Root Volume (1.75 folds), Chlorophyll (2.66 folds), Carotenoids (2.42 folds), Number of Fruits (1.76 folds), Fruit Biomass (2.02 folds), Total Soluble Sugars (2.32 folds), Total Soluble Proteins (1.70 folds), and nutraceutical parameters as Lycopene (1.42 folds), β-carotene (2.65 folds) and Ascorbic Acid (1.54 folds), along with significant (p < 0.05) reduction in the Disease Severity Index (84.34%-21.23%), over the pathogen affected plant taken as control. The fruits and leaves garnered under TF-I displayed Total Polyphenol Content (TPC) of 74.5 and 126.9 mg g^-1 gallic acid, respectively, with 83.73% DPPH and 72.25% FRAP activity, indicating the elicitation of antioxidant properties in tomato fruits. EDS analyses showed 21.53% Si in SMS, and plant mapping investigation indicated a substantial accumulation of Si, which is well conceded to promote growth, disease resistance, and antioxidant parameters. The study also endorsed the use of PM over TP, as TF-I recorded an acceptable conidial count (2.22 × 10⁸ cfu/g) towards the end of six months storage period over other bioformulations. Overall, the study envisages the development and application of innovative methodology (TF-I), offering an eco-friendly alternative for producing quality crops and a sustainable solution to waste management, thus delivering a holistic contribution towards the circular economy.

Keywords: Antioxidant activity; Solanum lycopersicum; Spent mushroom substrate; Trichoderma asperellum; Waste management; Wilt control.