Management Economics of Foot and Stem Rot of Mesta Incited by Phytophthora parasitica

Trials were conducted at the Agricultural Research Station, Amadalavalasa for three consecutive years of Kharif 2007–08, 2008–09 and 2009–10 to investigate on the economical control of foot and Stem rot of Hibiscus sabdariffa L. Among the nine treatments studied including an untreated check in a Randomized Complete Block Design with three replications, the treatments T5(Seed treatment with Metalaxyl 8% + Mancozeb 64% (Master) 3g/kg + soil application with Trichoderma viride 10g/kg of farm yard manure (FYM) and T6 (seed treatment with Cymoxanil 8% + Mancozeb 64% (Curzate M8) 3g/kg seed + soil application with Pseudomonas fluorescens 10g/kg of FYM, recorded lowest foot and stem rot incidence (9.6% and 9.0% respectively) and highest fibre yield (20.7and 20.9 q/ha respectively). However, the benefit was observed to be highest for T3 (seed treatment with Trichoderma viride @ 5g/kg seed) (1:1.75) followed by T4 (Seed treatment with Pseudomonas fluorescens @ 5g/kg seed (1:1.64). The benefit was observed to be lowest for combination treatments of T5 (1:0.09) and T6 (1:0.05). However, there was gradual reduction in disease incidence from year to year in combination treatments compared to single best treatments T3 and T₄. Disease reduction in combination treatments compared to single best treatments can be attributed to rapid multiplication and colonization of bio-agents in the farm yard manure.