Abstract

White mold of marigold, induced by Sclerotinia sclerotiorum, is a destructive fungal infection that results in significant crop losses annually. This experiment assessed the effectiveness of several chemical fungicides and biocontrol agents in mitigating white mold disease. Laboratory, net house, and field experiments were conducted to assess the fungicides and biological agents. Under in vitro conditions, all fungicides demonstrated a significantly greater efficacy than the control in suppressing pathogen development. Score 250EC, Faja 70WP, Secure 600WG, Folicur 250EC, and Tilt 250EC were the most efficacious, as they entirely suppressed (100%) the pathogen's growth. Under field conditions, Score 250EC and Faja 70WP exhibited superior performance in the number of uninfected flowers/plants (In high-yielding varieties (HYV), 15.00 and 14.53; in local variety, 26.93 and 26.50, respectively) and the minimal count of infected flowers/plants throughout both varieties. The lowest disease incidence (10.55% in HYV and 24.40% in local variety), severity (22.83% in HYV, while local variety exhibited 14.02%), and reduction over control were seen with Score 250EC and Faja 70WP fungicides in both varieties. In the pot and field trial, neem oil cake was identified as an efficient biocontrol agent, increasing the number of uninfected flowers/plants and decreasing the number of infected flowers/plants in both varieties. In a pot experiment, neem oil cake resulted in 14.53 uninfected flowers/plants in HYV, whereas in a local variety, it was 19.87. Furthermore, in the field trial, the number of uninfected flowers/plants in the HYV was 15.39, whereas in the local variety it was 19.87. The incidence, severity, and decrease of disease in neem oil cake-treated plants were quite low compared to the control condition. Neem oil cake was identified as the second most effective substance in suppressing pathogen growth.

Key words: Sclerotinia sclerotiorum, Fungicides, Bio-agents, Management, Marigold.