PREFERENCES OF CHRYSOMELA-(=MELASOMA)-POPULI L AND CHRYSOMELA-TREMULAE F (COL, CHRYSOMELIDAE) FOR LEUCE SECTION POPLAR CLONES

Differential feeding and egg laying responses by two chrysomelids Chry somela populi L. and C. tremulae F. to 15 clones of Leuce poplars were investigated. Observations were made at experimental plots from 1988 through 1991. Poplar clones were ranked in term of their positive effe ct on both insect feeding and oviposition: P. tremula L. x P. tremuloi des Michx. > P. tremula x P. alba L. > P. alba. For feeding ana ovipos ition, the two chrysomelid species clearly preferred P. tremula x P. t remuloides. P. alba appeared to be least preferred, especially for C. tremulae. Overall, the correlations between feeding and egg laying wer e significant for both species. This study also demonstrated temporal variations of the preferences of these two chrysomelids. The implicati ons of high population levels were discussed in relation to insect pre ference.