HOST RACES OF RHAGOLETIS-CERASI L (DIPT, TEPHRITIDAE) - EFFECT OF PRIOR ADULT EXPERIENCE ON OVIPOSITION SITE PREFERENCE

Results of first laboratory experiments carried out in 1974 and 1976 i ndicated that exposure of Prunus and Lonicera host races of the Europe an cherry fruit fly, Rhagoletis cerasi L., to a given natural or artif icial oviposition substrate for 5 successive days influenced the ovipo sitional preference of each host race for the two fruit types (cherrie s and Lonicera berries) offered in a 2-choice test. The greater behavi oural plasticity of the Prunus host race and the more stereotyped beha viour of the Lonicera host race was confirmed in a second (1987) and t hird experimental series (1993) using different bioassay methods. The evolutionary aspects of this induced preference by prior experience ar e discussed.