Efficacy of Fungicides against Powdery Mildew in Luffa cylindrica under Field and in-vitro Conditions

A field and laboratory study were conducted in Kharif 2024 to evaluate the efficacy of various fungicides against powdery mildew (Erysiphe cichoracearum) in sponge gourd (Luffa cylindrica). The experiment involved eight treatments, including both chemical fungicides and a control, applied as foliar sprays in a randomized block design with three replications. Disease severity was assessed using the 0 to 9 disease rating scale, and the effectiveness of treatments were determined by measuring mean per cent disease severity, per cent disease control, and area under the disease progress curve values. Among the tested fungicides, Azoxystrobin 11% w/w + Tebuconazole 18.3% at 0.15% (T₃) and Kresoxim methyl 18% + Mancozeb 54% WP at 0.2% (T₆) provided the greatest reduction in disease severity (12.28% and 15.18%), highest disease control (66.23% and 59.51%), and the lowest AUDPC values (311.10 and 531.15). In vitro evaluations supported these results, with T₃ and T₆ exhibiting the lowest disease severity ratings and maximum resistance in leaf disc assays. In contrast, the control plot (water spray) showed maximum disease progression and severity. The study concludes that Azoxystrobin 11% w/w + Tebuconazole 18.3% and Kresoxim methyl 18% + Mancozeb 54% WP are highly effective for managing powdery mildew in sponge gourd under both field and laboratory conditions, offering promising options for integrated disease management strategies.