Rhinoceros beetle is mainly a pest of coconut and oil palms. Adults damage palms by boring into the centre of the crown, where they injure the young, growing tissues and feed on the exuded sap.
Life cycle
Eggs are laid in manure pits or other organic matter and hatch in 8-12 days. Larvae takes another 82-207 days before entering an 8-13 day non feeding prepupal stage. Pupal stage lasts for 17-28 days.
Adults remain in the pupal cell for 17-22 days before emerging and flying to palm crowns to feed.
The beetles are active at night and hide in feeding or breeding sites during the day. Mostly mating takes place at the breeding sites.
Adults may live for 4-9 months and each female lays 50-100 eggs during her lifetime.
Management
Chop and burn decaying logs or break them up and destroy any adult beetles developing inside.
Cut stumps as close to the soil surface as possible. A hooked wire can be used to extract and destroy rhinoceros beetle adults feeding in coconut trees.
Fungus, Metarhizium anisopliae can be applied in manure pits @ 4 kg/tonnes to control the grubs that feed on the decaying matter
Apply mixture of neem seed kernel powder + sand (1:2) @150 g per palm in the base of the 3 inner most leaves in the crown
Place phorate 10 G 5 gms mixed with sand in two inner most leaf axils for 2 times at 6 months intervals.
Place three napthalene balls at leaf axil at the top of the crown. Treat the longitudinally split tender coconut stem and green petiole of fronds with fresh toddy and keep them in the garden to attract and trap the beetles. Use pheromone traps with rhinolure at 12/ha for trapping the adults and destroy them
Remedial measures
Apply 50 kg of FYM or compost or green manure, 1.3 kg urea (560 g N), 2.0 kg super phosphate (320 g ) and 2.0 kg muriate of potash (1,200) g ms in two equal splits. During 2nd, 3rd and 4th year.
For nut bearing coconut, root feed with TNAU coconut tonic at 200ml/palm, once in six months. Apply 200 g of borax/palm/year in two splits.
A.Suganthi
& A.P.Sivamurugan
KVK, VirinjipuramTamil Nadu Agricultural University, Vellore
