Biological Control of Radopholus similis (Cobb) Thorne Using Endophytic Bacteria and Fungi in Musa paradisiaca L.

Abstract

Plantain (Musa spp.) is a crop of major economic importance in Nicaragua, both for domestic consumption and for export. The present study evaluated the effect of combining endophytic strains of Bacillus subtilis (B1 and B2), Bacillus cereus, Pseudomonas sp., and Saccharomyces sp., isolated from plantain roots, as a biological alternative for the management of Radopholus similis. A completely randomized design was employed, using single and combined inoculations of bacteria and fungi in vitroplants of the cultivar CEMSA ¾. The percentage of nematode penetration and the percentage of control were quantified. An arcsine transformation was applied to homogenize variances, followed by analysis of variance and mean separation using Tukey’s test (0.05). Single inoculations of Saccharomyces sp. and the control treatment showed the highest nematode penetration rates. Regarding to the control percentage, the highest values were obtained with the combined inoculations composed by Bacillus cereus + Pseudomonas sp. + Saccharomyces sp. + Bacillus subtilis (B1), Bacillus subtilis (B2) + Pseudomonas sp. + Saccharomyces sp., as well as Bacillus subtilis (B2) + Pseudomonas sp. + Saccharomyces sp. Similarly, Bacillus subtilis (B2) alone and the combination of Saccharomyces sp. + Bacillus subtilis (B1), reduced nematode populations by up to 83%. The inoculations of Bacillus cereus + Pseudomonas sp. + Saccharomyces sp. + Bacillus subtilis (B2) and Bacillus cereus + Pseudomonas sp. + Saccharomyces sp. + Bacillus subtilis (B1) resulted in the greatest plant height. Combined inoculations improved the efficiency of Radopholus similis control, representing a sustainable and environmentally friendly alternative