The primary evidence of infestation is the emergence of larvae from the holes and the presence of cocoons outside the pods. There is usually no visible damage to the seeds when the infested pods are split open.
Damage is caused by the larvae of the adult brown beetle (C. Serratus). Eggs (small and translucent) are laid by the mature adult beetle on the outside of the pod. After hatching, the young larvae dig directly through the pod wall from the egg. It feeds on the cotyledons of the kernel until maturity. The adult beetle then makes a large hole in the pod. The adult beetle is oval-shaped and brown in colour and is usually about 7mm in length. Under optimum conditions, it takes about 40-42 days to complete its life cycle. The beetle's development thrives under temperatures of 30-33°C.
Treat groundnut pods with neem seed powder or black pepper powder. You can also treat pods with Neem oil, Pongamia oil or Eucalyptus oil. Store Pods in air-tight polythene bags or in galvanized metallic/PVC seed bins.
Always consider an integrated approach with preventive measures together with biological treatments, if available. Fumigate with Methyl bromide with 32g/m³ for 4 hours. Follow this with Chlorpyriphos seed treatment @ 3g/kg, Spray Malathion 50EC @ 5ml/l, 2 to 3 times on the walls of warehouses, as well as on bags. Spray Deltamethrin @ 0.5ml/L on bags.