The present investigation is focused on exploring the possibilities of identifying biomolecules from the fruiting body of the medicinal mushroom Ganoderma lucidum against the mango anthracnose pathogen Colletotrichum gloeosporioides. The fruiting body (cap and stipe portion) of G. lucidum extracted with ethyl acetate solvent at a maximum inhibitory concentration of 1 percent exhibited the maximum mycelial growth inhibition of C. gloeosporioides with 70.10 percent and 40.77 percent, respectively. Furthermore, subjecting the ethyl acetate extracts from the cap portion of G. lucidum through thin layer chromatography (TLC) revealed the presence of two bands with Rf values of 0.38 and 0.35. The compounds eluted from band 1 recorded with the maximum mycelial growth inhibition of C. gloeosporioides by 53.77 percent followed by band 2 (46.33 percent) using an agar well diffusion test. Similarly, the analysis of ethyl acetate extracts from the cap portion of G. lucidum through Gas Chromatography-Mass spectroscopy (GC-MS) revealed the presence of the organoheterocyclic compound benzothiazole, as expressed in the highest peak area at 22.03 RT with the highest probability percentage (97%). Confirmation of the antifungal nature of benzothiazole was obtained by testing the standard sample of benzothiazole which showed a cent percent of inhibition on mycelial growth of C. gloeosporioides at 50 ppm minimum fungicidal concentration. Furthermore, benzothiazole caused abnormality in the mycelial structures, viz., distortion, shrinkage, clumping of mycelium, conidial malformation, and complete arrestment of conidial germination of C. gloeosporioides as observed through Scanning Electron Microscopy. The research on biomolecular extract of G. lucidum could be a novel and interesting concept for the possibility in suppression of plant pathogenic microbes in the natural field.

In this study, the volatilomes of naturally growing plant leaves were immobilized in a suitable substrate to enhance vapors’ diffusion in the soil to eradicate the Fusarium wilt pathogens in Tomato. Volatilomes produced by Mentha spicata leaves immobilized in vermiculite ball was found to be effective and exhibit 92.35 percent inhibition on the mycelial growth of Fusarium oxysporum f. sp. lycopersici (FOL). Moreover, the volatilomes of M. spicata immobilized vermiculite balls were tested based on the distance traveled by the diffused volatilomes from the ball and revealed that the volatilomes of M. spicata traveled up to 20 cm distance from the center of PVC (Polyvinly chloride) chamber showed maximum reduction in colony growth of FOL at 12th day after inoculation. Tomato plants inoculated with FOL revealed increased expressions of defense gene, pathogenesis related protein (PR1) with 2.63-fold after 72 h and the gene, transcription factor (WRKY) increased with 2.5-fold after 48 h on exposure to the volatilomes of M. spicata vermiculite balls. To the best of our knowledge, this is the first report on development of volatilomes based vermiculite ball formulations. This result indicated that the volatilomes of M. spicata are promising phyto-fumigants for management of Tomato Fusarial wilt.

Several macrobasidiomycete fungi have potential biological properties naturally to combat fungal diseases. F.oxysporum f.sp. lycopersici is a soilborne ascomycetous fungus, which causes disease in several vegetable crops. The present study aimed to explore the antifungal activity of VOCs produced by several macrobasidiomycete fungi against F. oxysporum f.sp. lycopersici. The VOCs emitted by macrobasidiomycete fungi were demonstrated by the inverted sealed plate assay against the target pathogen. Among the mushroom isolate tested in vitro, the VOCs exhibited from Coprinus cinereus inhibited 70 % mycelial growth of F. oxysporum f.sp. lycopersici, followed by Ganoderma lucidum (60.28 %) and Lentinus edodes (35.28 %). In addition to inhibition of the pathogen, the headspace volatiles emitted by the effective isolate were trapped by Tenax column and subjected to GC-MS analysis. A total of 15 and 25 VOCs were identified from C. cinereus and G. lucidum, respectively. Among them, Alfa copaene showed a peak area percentage of 7.82 (14.99 RT) in Coprinus cinereus. followed by 2 undecanone. Similarly, trichloromethane and 1- pentanol produced from G. lucidum, showed high relative abundance of 71.5 per cent at 9.84 RT and 70.3 per cent at 2.69 RT, respectively. The VOCs produced by macrobasidiomycete fungi could possess antimicrobial activities against the fungal pathogen. These volatile compounds may be explored as a novel biocontrol agent against soil borne pathogens of vegetable crop.

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