BIOPRIMING BANANA WITH PLANT GROWTH-PROMOTING ENDOPHYTIC BACTERIA INDUCES SYSTEMIC RESISTANCE AGAINST BANANA BUNCHY TOP VIRUS
Bunchy top, caused by Banana bunchy top virus (BBTV), is a serious disease of banana. Plant growth-promoting rhizobacterial and endophytic bacterial strains were used to induce systemic resistance against BBTV in tissue-cultured banana plantlets. The experiment involved the application of single strains and mixtures of Pseudomonas fluorescens strain Pf1 and strain CHA0 (rhizobacteria) and Bacillus subtilis strain EPB22 (endophyte), which were formulated and applied to plants as a 1% soil drench. The tissue-cultured plantlets were challenged with viruliferous aphids to ensure transmission of BBTV to all the plants. Plants treated with mixtures of endophytic and rhizobacterial formulations showed minimum infection of 20% (an 80% reduction over control plants). A low titre of BBTV was recorded in treated plants in ELISA tests. Some treated plants tested negative for BBTV in PCR. The expression of defence-related chemicals and enzymes, such as phenol, phenylalanine ammonia lyase, peroxidase and polyphenol oxidase, and pathogenesis-related proteins, such as chitinase and ß-1,3 glucanase, were more pronounced in the endophytic bacteria-treated banana plants than in control plants. Thus biopriming of tissue-cultured plants is effective in the management of an economically important plant disease.
Harish, S., Kavino, M., Kumar, N. and Samiyappan, R. (2009). BIOPRIMING BANANA WITH PLANT GROWTH-PROMOTING ENDOPHYTIC BACTERIA INDUCES SYSTEMIC RESISTANCE AGAINST BANANA BUNCHY TOP VIRUS. Acta Hortic. 828, 295-302
defence-related enzymes, disease incidence, rhizosphere and endophytic bacteria, tissue-cultured plantlets