Management ofAlternaria Leaf Spot using Available Fungicides (Combi Products) in Sunflower

Alternariaster leaf spot/blight caused by Alternariaster helianthi is an important disease of sunflower, caused yield losses upto 80%. It is seed and air borne. Management of this disease is very important to avoid yield losses, hence, this experiment was planned with available fungicides (combi products) in the market.

A field experiment was carried out on management of Alternariaster leaf spot disease for three years i.e., kharif 2018, 2019 and 2020 at RARS, Nandyal under AICRP on Sunflower scheme. Seven treatments were imposed in three replications with different fungicides by using the hybrid KBSH-44 in RBD design.

Pooled analysis results indicated that among different treatments, the treatment T₃: (Seed treatment with carbendazim 12% + mancozeb 63% wp @ 2 g/kg seed followed by two foliar sprays with Trifloxystrobin 25%+ tebuconazole 50% (Nativo 75WG)@ 0.25 g/l) has recorded low severity (PDI) of 37% with higher yield of 1382 kg/ha, which was followed by the treatment T₁ (Seed treatment with carbendazim 12% + mancozeb 63% WP (SAAF 75 WP) @ 2 g/kg seed followed by two foliar sprays with difenconazole 25% + propiconazole 25% (TASPA 500EC) @ 0.3 ml/l) which has recorded disease severity (PDI) of 40.95% and yield of 1363 kg/ha, where as control recorded high PDI of 53.38% and lower yield of 1200 kg/ha. Regarding B:C ratio, the treatment T₁ recorded high B:C ratio i.e., 1.65, followed by T₄ and T₃ which recorded 1.59 and 1.57, respectively. Hence, it was concluded that the above three treatments were recommended for disease management as they are at par with each other and recorded more B:C ratio than others.