Effect of endophytic bacteria Bacillus subtilis EPC 5 on basal stem rot disease spread and nut yield in coconut plantations

Abstract

The wood degrading fungi Ganoderma lucidum (Leys) Karst causing Basal Stem Rot (BSR) in coconut plantation is the most destructive disease in Southern India. The control of this soil borne pathogen is particularly complex due to their occurrence in dynamic environment at the interface of the root with the soil. Hence, combinations of biocontrol agents differing in their mode of action especially with endophyte have been explored. The endophytic bacteria Bacillus subtilis EPC 5 from healthy coconut palm root showed high inhibition activity among fifty five isolated strains. Further, talc-based formulation incorporating Pseudomonas fluorescens Pf1 and Trichoderma viride Tv1 were developed and used individually, in combination to manage highly virulent, laccase producing soil borne pathogen. The result indicated that soil application of above mentioned antagonist in combination @ 100 g each enriched with organic substrate for four times per year, significantly reduced the disease severity with high nut yield at two different locations of disease endemic areas.