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Aims@#Endophytic fungi are a diverse group of microorganisms that stay asymptomatically in the healthy tissues of the host. Many fungal endophytes are associated with the tea plant (Camellia sinensis) and the pathogens of the tea plant have the potential to grow as endophytes or act as latent pathogens during the initial growth of the plant. The present study aimed at screening tea endophytic fungi with the potential for control of a few critical phytopathogens, Fusarium sp., Lasiodiplodia theobromae, Pestalotiopsis sp. and Sclerotinia sclerotiorum while evaluating the efficiency of growth inhibition of these phytopathogens by the endophytic fungal isolates using in vitro assays.@*Methodology and results@#Five endophytic fungal strains; Colletotrichum gloeosporioides, C. siamense, Daldinia eschscholtzii, Pseudopestalotiopsis chinensis and Phyllosticta capitalensis isolated from leaves of C. sinensis in Sri Lanka were evaluated for growth inhibition against plant pathogens; Fusarium sp., L. theobromae, Pestalotiopsis sp. and S. sclerotiorum using the dual culture assay and volatile compound-mediated inhibition assay. All the fungal endophytes used in this study exhibited antifungal activity against Fusarium sp., Pestalotiopsis sp. and S. sclerotiorum in the dual culture assay on PDA. Daldinia eschscholtzii (67.30%) and C. gloeosporioides (61.54%) showed strong antagonistic activity against S. sclerotiorum, while P. capitalensis (42.30%) demonstrated moderate activity. All the endophytic fungal strains showed moderate antifungal activities against Fusarium sp. The percentage growth inhibitions of Pestalotiopsis sp. by all the endophytic isolates tested were below 25.00%. In the volatile compound-mediated inhibition assay, none of the endophytic isolates showed visible inhibition against the phytopathogens used.@*Conclusion, significance and impact of study@#In this study, the fungal endophytes which showed potential antagonistic activity against the tested phytopathogens can be used to develop commercialized products of fungal biocontrol agents (BCAs) for controlling plant fungal diseases.
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Aims@#Meloidogyne incognita adversely affects numerous crop plants worldwide. Therefore, the modern world has been moving towards biocontrol methods to prevent nematode attacks. This study was aimed to (i) investigate the potential use of Trichoderma harzianum NFCF160 and T. virens Isf-77 in managing M. incognita in soil and (ii) identify trapping mechanisms employed by both Trichoderma strains to suppress M. incognita.@*Methodology and results@#Three weeks old, Basella alba L. plants were subjected to five different treatments. The above and below ground growth parameters and the galling indices of these plants were measured every four weeks for three sampling times. Trapping mechanisms employed by Trichoderma strains were examined following plate assays. Plants treated with T. harzianum NFCF160 and T. virens Isf-77 had significantly higher values for the total number of leaves (34 ± 2.84) and (27 ± 2.61), fresh weight of the shoot (81 ± 9.51 g) and (91 ± 9.70 g), dry weight of the shoot (71 ± 5.24 g) and (62 ± 5.81 g), respectively eight weeks after inoculation of M. incognita. Significantly low galling indices (2 and 2) were recorded in B. alba treated with Trichoderma strains. Both Trichoderma strains exhibited various nematode-trapping mechanisms, such as non-constricting rings and adhesive spores.@*Conclusion, significance and impact of study@#This investigation highlighted the potential of both Trichoderma strains as biocontrol agents to control M. incognita effect in sustainable agriculture.