Management of Gerbera Leaf Spot Caused by Alternaria alternata, Under Protected Cultivation

Leaf spot causd by Alternaria alternata (Fries) Keissler. is one of the most destructive diseases of the gerbera (Gerbera jamesonii Hook) flowering crop grown under protected conditions, causing qualitative as well as quantitative losses. The pathogen/disease is very difficult to control to manage alone with fungicides. Therefore, present studies were attempted to manage leaf spot disease with the integration of effective fungicides, botanicals and bioagents. Results revealed that all the treatments significantly reduced the leaf spot incidence and intensity, over untreated control. Amongst all the treatments significantly least average disease incidence was recorded withthe treatmentMancozeb 75WP + T. viride + A. sativum (15.65%), followed by Hexaconazole 5 EC + Mancozeb 75 WP (17.50%) and Mancozeb 75 WP + T. viride (18.36%). Rest of the treatments recorded average disease incidence in the range of 20.21% (Mancozeb 75 WP + A. sativum) to 37.16% (C. longa) as against 50.72% in untreated control. Similarly, significantly least average disease intensity was recorded with the treatment Mancozeb 75 WP + T. viride + A. sativum (14.50%), followed by Hexaconazole 5 EC + Mancozeb 75 WP (16.34%) and Mancozeb 75WP (19.34%). Rest of the treatments recorded average disease intensity in the range of 21.24% (T. viride) to 26.00% (C. longa) as against 38.58 per cent in untreated control. All the treatments significantly reduced both incidence and intensity of the disease over untreated control.