Development of integrated biocontrol strategy for the management of stem rot disease (Fusarium oxysporum f.sp. Vanillae) of Vanilla

Stem rot disease of vanilla caused by Fusarium oxysporum f.sp. vanillae is a major constraint in its cultivation in Kanyakumari District. The in vitro studies on the mycelial growth of the pathogen expressed the superior efficacy of the native isolate of Pseudomonas fluorescens (Pf_NI) that recorded an inhibition zone of 25.00mm and was followed by T. harzianum. Under field conditions soil application of Pf_(NI) followed by carbendazim spray (0.2%) after 30 days of Pseudomonas application recorded the lowest disease incidence of 3.77, 4.03 and 3.67 per cent in three years and exerted 79.95, 80.50, 80.48 per cent reduction in disease over the control plot respectively. Among the bioagents, the soil application of Pf_(NI) followed T. harzianum after 30 days and another dose of Pf_(NI) after 30 days recorded a significant disease reduction of 69.84, 68.24 and 70.21 per cent in three consecutive years.