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Mushroom fungi secrete antifungal, antibacterial and antiviral bioactive compounds of therapeutic and pharmacological value. Very limited work has been done on the exploration of antimicrobial principles from macrobasidiomycetes against plant pathogens. In this view, a study was proposed to screen eight mushroom fungi viz., Auricularia polytricha, Coprinus comatus, Ganoderma lucidum, Volvariella volvaceae, Lentinus edodes, Pycnoporus sanguineus, Schizophyllum commune, Trametes versicolor against spore germination and mycelial growth of Colletotrichum capsici , the fruit rot pathogen of Chilli and to extract antimicrobial molecules from the selected mushroom fungi using different solvents viz., Chloroform, Diethyl ether and Ethyl acetate. Results from dual culture technique revealed that Ganoderma lucidum, Auricularia polytricha and Lentinus edodes showed maximum antifungal activity by inhibiting the mycelial growth of C. capsici (54.81%, 53.70 % and 45.55% respectively) with maximum inhibition zone of (4.86 mm, 2.86 mm and 4.86 mm respectively). Though the Chloroform, Diethyl ether and Ethyl acetate fractions of G. lucidum cell free extracts inhibited spore germination of C. capsici both at 12 and 24 hours, maximum inhibition of spore germination was observed at 24 hours. Among the mushroom fungi, the chloroform extracted fractions followed by Diethyl ether and Ethyl acetate fractions of G. lucidum cell free culture filtrates exhibited maximum inhibition of spore germination of C. capsici (inhibition of 88 %, 79% and 78 % respectively) at 24 hours. Similarly, maximum inhibition of mycelial growth of C. capsici with 40 %, 34.07% and 29.25 % inhibition respectively was recorded in the chloroform extracted fractions followed by Diethyl ether and Ethyl acetate fractions of G. lucidum cell free culture filtrates when compared to solvent extracted fractions of L. edodes and A. polytricha by agar well diffusion technique. The chloroform extracted metabolite of G. lucidum followed by Ethyl acetate and Diethyl ether fractions at 2000 ppm concentration inhibited maximum mycelial growth of C. capsici (60.55 %, 58.88 % and 55.47 % respectively). It is well proven that chloroform extracted fractions of G. lucidum possess antimicrobial activities against the growth of C. capsici. Hence, further studies towards the identification of these compounds will pave for development of fungicides against C .capsici.

Chemical pesticides have an immense role in curbing the infection of plant viruses and soil-borne pathogens of high valued crops. However, the usage of chemical pesticides also contributes to the development of resistance among pathogens. Hence, attempts were made in this study to identify a suitable bacterial antagonist for managing viral and fungal pathogens infecting crop plants. Based on our earlier investigations, we identified Bacillus amyloliquefaciens VB7 as a potential antagonist for managing Sclerotinia sclerotiorum infecting carnation, tobacco streak virus infecting cotton and groundnut bud necrosis infecting tomato. Considering the multifaceted action of B. amyloliquefaciens VB7, attempts were made for whole-genome sequencing to assess the antiviral activity against tomato spotted wilt virus infecting chrysanthemum and antifungal action against Fusarium oxysporum f. sp. cubense (Foc). Genome annotation of the isolate B. amyloliquefaciens VB7 was confirmed as B. velezensis VB7 with accession number CP047587. Genome analysis revealed the presence of 9,231,928 reads with an average read length of 149 bp. Assembled genome had 1 contig, with a total length of 3,021,183 bp and an average G+C content of 46.79%. The protein-coding sequences (CDS) in the genome was 3090, transfer RNA (tRNA) genes were 85 with 29 ribosomal RNA (rRNA) genes and 21 repeat regions. The genome of B. velezensis VB7 had 506 hypothetical proteins and 2584 proteins with functional assignments. VB7 genome had the presence of flagellin protein FlaA with 987 nucleotides and translation elongation factor TU (Ef-Tu) with 1191 nucleotides. The identified ORFs were 3911 with 47.22% GC content. Non ribosomal pepide synthetase cluster (NRPS) gene clusters in the genome of VB7, coded for the anti-microbial peptides surfactin, butirosin A/butirosin B, fengycin, difficidin, bacillibactin, bacilysin, and mersacidin the Ripp lanthipeptide. Antiviral action of VB7 was confirmed by suppression of local lesion formation of TSWV in the local lesion host cowpea (Co-7). Moreover, combined application of B. velezensis VB7 with phyto-antiviral principles M. Jalapa and H. cupanioides increased shoot length, shoot diameter, number of flower buds per plant, flower diameter, and fresh weight of chrysanthemum. Further, screening for antifungal action of VB7 expressed antifungal action against Foc in vitro by producing VOC/NVOC compounds, including hexadecanoic acid, linoelaidic acid, octadecanoic acid, clindamycin, formic acid, succinamide, furanone, 4H-pyran, nonanol and oleic acid, contributing to the total suppression of Foc apart from the presence of NRPS gene clusters. Thus, our study confirmed the scope for exploring B. velezensis VB7 on a commercial scale to manage tomato spotted wilt virus, groundnut bud necrosis virus, tobacco streak virus, S. sclerotiorum, and Foc causing panama wilt of banana.

Biological control would be a prospective alternative to the existing chemical nematicides to keep the root knot nematode, Meloidogyne incognita regimented. Macrofungi are fungal species that produce fruiting bodies visible to the naked eye. Many of the macro basidiomycetous fungi produce several compounds which recorded with nematicidal and insecticidal properties. In this study, eleven macro basidiomycetes were screened in vitro against M. incognita. The crude culture filtrates were extracted and evaluated for their antagonistic effect on egg hatching and juvenile mortality of M. incognita. Crude culture filtrates of Ganoderma lucidum and Lentinus edodes were found to be toxic to egg masses and exhibit the highest mortality rate. The results revealed that the crude culture filtrates of G. lucidum reduced the M. incognita egg hatching 89.8% and increased the juvenile mortality by 93.5% which was followed by L. edodes which inhibited the egg hatching by 85% and caused juvenile mortality by 90.83%.