The medicinal plant, Withania somnifera is attributed by valuable medicinal properties and is widely cultivated. It is a need to take care of this plant from synthetic agrochemicals that may be hazardous for health and environment. The aim of the present study was to isolate and screen the endophytic fungi of W. somnifera that have potential of plant growth promotion and antagonism against plant pathogens. In this study, 22 potential fungal endophytes comprising of species of Alternaria, Aspergillus, Fusarium, Nigrospora, Colletotrichum and Talaromyces identified at National Fungal Culture Collection of India (NFCCI), Pune were isolated. The potential isolate, Talaromyces trachyspermus was confirmed by BLAST and phylogenetic analysis of sequences of rDNA ITS, LSU (D1 D2) and β-tubulin genes. Among all the isolates, T. trachyspermus exhibited comparatively higher activity for hydrolytic enzymes, protease, chitinase, amylase, cellulase and pectinase that are required for antagonistic property. It was observed to be a promising biocontrol agent against plant pathogen, Sclerotinia sclerotiorum. This strain is also characterized with high level of indole acetic acid (IAA), siderophore synthesis, and phosphate solubilization activities that are important for plant growth promotion. This is the first report on endophyte, T. trachyspermus from W. somnifera having potential plant growth promoting traits and biocontrol, which can be further exploited to enhance the medicinal value of the plant.

Of the total 40 endophytic fungi isolated from foliar tissues of medicinal plant Stevia rebaudiana Bertoni, a fungal isolate, Aspergillus flavipes, was subjected to bioassay guided fractionation. The fractionation was found active against medicinal plant pathogen Sclerotinia sclerotiorum with an inhibition zone of 29 mm in size. Further the metabolite was extracted which shows 20% growth inhibition in 24 h and 46% after 48 h, respectively. Bioassay guided chemical compound was identified as 1,2-benzenedicarboxylic acid, mono(2-ethylhexyl) ester. On the basis of morphological characters and rDNA sequencing of ITS region the endophyte was identified as Aspergillus flavipes which showed promising plant growth promotory properties.

Fusarium oxysporum is one of the most damaging plant pathogens causing Fusarium wilt in many plants leading to serious economic loss. The fungus colonizes the xylem, which leads to resistance in water flow in the plant thereby affecting the rate of photosynthesis. The present study focuses on the selection of bacterial endophytes isolated from tomato plants and evaluating their potential to antagonize Fusarium oxysporum in tomato in vivo. The results obtained indicated that two endophytic isolates, namely Pseudomonas fluorescens BUMD5 and Bacillus velezensis BUMD9, could act as efficient biocontrol agents (BCAs) as they inhibited the growth of pathogen by 67.2 and 69.1%, respectively, in vitro. Both the isolates were found to produce hydrolytic enzymes chitinase and protease. They also produced siderophore and hydrogen cyanide (HCN). The consortia of both the isolates significantly reduced the infection percentage by about 67% and a 3-fold decrease in disease severity was observed as compared to pathogen control. The treatment of infected plants with these potent isolates was also beneficial in improving the overall photosynthetic performance index (PI). Thus, plants treated with consortia of these isolates exhibited better overall plant growth despite being infected by the pathogen.