In-vitro and in-silico studies on plant growth promotion of endophytic fungi of Ischaemum ciliare Retz.

The current work sought to characterize the secondary metabolites produced by endophytic fungi from the perennial grass Ischaemum ciliare Retz. and examine in-vitro and in-silico investigations on plant growth promotion. Cochliobolus fallax, Cochliobolus sp., Pestalotiopsis sp., Fusarium oxysporum, and Penicillium islandium were isolated from the aerial part of I. ciliare, and two endophytic fungi, Curvularia protuberata and Pestalotiopsis guepinii, were identified based on ITS rDNA sequence analysis. Furthermore, C. protuberata, F. oxysporum, and P. guepinii demonstrated high antagonistic activity against pathogenic fungal and bacterial strains. They showed significant plant growth promotion in the ethyl acetate extracts of C. protuberata and P. guepinii and the methanolic extract of I. ciliare on Capsicum annuum and Zea mays seedlings in vitro. OHR-LC MS analysis of P. guepinii ethyl acetate extract and I. ciliare methanolic extract identified ten and seventeen potential secondary metabolites, respectively. Furthermore, the docking analysis established the ligand-receptor interaction. It revealed that eight out of ten P. guepinii compounds and nine out of seventeen I. ciliare compounds have a strong binding affinity towards 3OGM, 4LDY, and 6KU3 target proteins. The endophytic fungal and host metabolite research in-vitro and in-silico aids in predicting compounds with bioactive principles, bio-control agents, and plant growth promoters.