Fusarium wilt of banana is the most devastating disease caused by Fusarium oxysporum f.sp. cubense (Foc). In order to combat the early onset of Fusarium wilt disease, an experiment was carried out on biohardening of tissue cultured plantlets. Six bacterial endophytes were observed to inhibit the growth of Foc in vitro. Among the six bacterial endophytes, Bacillus amyloliquefaciens (VB7) inhibited mycelial growth of Foc to an extent of 70.58% over control. Further, these bacterial endophytes were used for biohardening of the tissue cultured banana plantlets cv. Ney Poovan (AB) during primary and secondary hardening stages. Among the bacterial endophytes, B. amyloliquefaciens was found to significantly enhance plant height, leaf production, root numbers and root length compared to untreated control. Activity of defense enzymes were  also enhanced and such increase in activity was observed to be to an  extent of 93.67% in peroxidase, 92.39% polyphenol oxidase, 97.60% phenylalanine ammonia lyase  and 26.23% in β-1, 3-glucanase defence enzymes in plants biohardened with B. amyloliquefaciens (VB7) over untreated control after inoculation of Foc. Tissue cultured plants of Ney Poovan biohardened with B. amyloliquefaciens   (VB7),   B.   paraconglomeratum   (YEB   PT2) and S. maltophilia (YEB RH2) were completely free from wilt incidence symptoms upto planting stage when challenged with Foc inoculum under pot culture conditions. As among these three endophytes, B. amyloliquefaciens (VB7) also influenced favourable growth promotion, it can serve as a potential biocontrol agent for management of Fusarium wilt of banana.

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