RHIZOBACTERIA-MEDIATED GROWTH PROMOTION OF BANANA LEADS TO PROTECTION AGAINST BANANA BUNCHY TOP VIRUS UNDER FIELD CONDITIONS
Bunchy top, caused by Banana bunchy top virus (BBTV), is one of the most destructive diseases of banana. BBTV retards plant growth, usually prevents bunch development and causes substantial economic losses. In the hills of the lower Pulney, Western Ghats, Tamil Nadu, India, the economically valuable hill banana Virupakshi (AAB genome, Pome subgroup) is extremely susceptible to BBTV. The area under cultivation has shrunk from 18,000 ha to 2000 ha despite farmers visually selecting healthy suckers to raise the next crop and spraying plants with systemic pesticides to control Pentalonia nigronervosa, the aphid vector of BBTV. An alternative method is needed to manage the disease. Plant-growth-promoting rhizobacteria (PGPR) have recently been shown to induce systemic resistance against fungi, bacteria and viruses as well as to enhance plant growth. Two strains of the PGPR Pseudomonas fluorescens (Pf1 and CHA0), formulated with the carrier chitin, were investigated for their efficacy in controlling BBTV. Banana plants treated at planting and at 3, 5 and 7 months after planting had significantly reduced bunchy top incidence under field conditions compared with the control treatment. The reduction in disease incidence was more pronounced with the chitin-amended CHA0 strain. Indirect ELISA indicated that the reduction in BBTV antigen concentration in banana plants corresponded to reduced disease ratings. The chitin-amended CHA0 strain also increased the leaf nutrient status and enhanced growth, bunch yield and the quality of the fruits compared with untreated plants.
Kavino, M., Harish, S., Kumar, N. and Samiyappan, R. (2009). RHIZOBACTERIA-MEDIATED GROWTH PROMOTION OF BANANA LEADS TO PROTECTION AGAINST BANANA BUNCHY TOP VIRUS UNDER FIELD CONDITIONS. Acta Hortic. 828, 69-76
BBTV, biocontrol, economic yield, induced systemic resistance, Musa, Pseudomonas fluorescens