Relative Efficacy of Number of Sprays of Fungicides on the Control of late Leaf Spot in Groundnut

The spray schedules in T₂ and T₃ consisting of two sprays and three sprays of mancozeb (0.25% + carbendazim (0.1%) respectively were significantly superior over control in reducing the late leaf spot (LLS) severity and increasing pod and haulms yields.

The spray schedule in T₃ (prophylactic spray after detecting the spores on spore trap followed by two sprays at 15 days interval) was found to be the best with the lowest disease severity (3.36 on 1 -9 disease scale) and highest pod (27.2Q/ha) and haulms (27.9 Q/ha) yields. The maximum incremental benefit cost ratio (IBCR) of 5.36 was obtained in the spray schedule of ‘T₃’ followed by T₂ (prophylactic spray followed by one spray after 15 days) with 5.30 IBCR. Late leaf spot of groundnut can economically be controlled by three sprays of mancozeb (0.25%) + carbendazim (0.1%) at 15 days interval and thus found suitable for its recommendation to the farmers.