Development of Matsumuraeses phaseoli (Lepidoptera: Tortricidae) Reared on an Artificial Diet under Outdoor Conditions and Its Over-wintering Stage

Abstract

Matsumuraeses phaseoli is one of the main pests that attack the flowers and pods of red bean (Vigna angularis) and mungbean (Vigna radiata) in Korea. To elucidate the developmental characteristics and over-wintering stage of M. phaseoli, several stages of the insect were observed through artificial rearing under outdoor conditions in Suwon (37°16′N 126°59′E 35ASL), Korea. In colonies in which neonate larvae were reared at about 2-week intervals for more than a year, the developmental period from larva to adult emergence became longer from spring to summer, but shorter from summer to autumn; aestivation was not observed during the summer season. The colony in which rearing started on Oct 8, 2008 over-wintered as pupae and emerged in late April next year with a survival rate of 6%. However, the colony in which the rearing started on Oct 23, 2008 over-wintered as mature larvae, pupated in late April, and emerged in early and mid-May with a survival rate of 2%. When the fifth instar larvae were transferred outside from the laboratory (25℃, 15L:9D) between November and February, no larvae could survive during the winter season. Some newly laid eggs and newly emerged adults could not hatch and could not survive, respectively, in outdoor conditions in November and December. These results suggest that neonate larvae of M. phaseoli that hatch in October can over-winter as late larvae or pupae in Suwon, Korea.