| Cyrtomon luridus (Boheman) has adapted to the medicinal plant Duboisia sp., introduced from Australia. Its larvae feed on roots, causing up to 100% mortality damages. The population dynamics and biological cycle were studied to determine future control methods in Duboisia sp., in Arapongas, Paraná State, Brazil, from 1993 to 1996. C. luridus presented annual life cycle in Duboisia sp. under natural conditions. The larval development period was 120 to 150 days, from January to May, reaching an average size of 19.0 ± 2.0 mm in soil depth ranging on 24.9 ± 8.6 cm to 45.0 ± 10.0 cm. The beginning of the pupal phase happened in April. The larval-adult viability ranged on 7.5% to 19.6%. The typical symptoms of attack appeared in an infestation level of 60 larvae... |
