BehaviorThe larvae feeds for 10 to 15 days on leaves and on maturity enter the soil and pupate below up to 15 cm depth. The adult beetles emerge after eight to 12 days and complete their life cycle in 27 to 32 days. Both the adults and larvae are capable of feeding on the ''Parthenium'' leaves thus checking the plant growth and flower production. Immature flowers are cut by the beetles in an effort to chew the soft tissues beneath the flowers. Plants may be completely defoliated at times.
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