OVIPOSITION PREFERENCES OF THE POLYPHAGOUS MOTH CHORISTONEURA-PARALLELA (LEPIDOPTERA, TORTRICIDAE) - EFFECTS OF PLANT-SPECIES, LEAF SIZE, AND EXPERIMENTAL-DESIGN

The fireworm Choristoneura parallela (Robinson) is a major pest of cra nberry in Neu Jersey. Eggs typically are laid on the leaves of various weed species, and larvae disperse unto cranberry by ballooning. We us ed laboratory-reared moths and greenhouse experiments to investigate o viposition preferences among 3 need species: greenbrier, Smilax rotund ifolia L.; leatherleaf, Chamaedaphne calyculata (L.); and sheep laurel . Kalmia angustifolia L. In no-choice tests conducted in screen cages using cuttings, leatherleaf received the most egg masses whereas the o ther species did not differ. In this test there were no differences am ong species in the latency to the Ist egg mass; and the latency betwee n the Ist and 2nd egg masses did not differ for greenbrier compared wi th the other species but it as shorter for leatherleaf than for sheep laurel. The results were similar in 3-way choice tests conducted in sc reen cages using cuttings with leatherleaf receiving the highest perce ntage of egg masses and the other species not differing. However, a di fferent preference hierarchy was found in 3-way choice tests conducted in plastic boxes using a single leaf of each species: greenbrier rece ived the highest percentage of egg masses, leatherleaf received more t han sheep laurel and sheep laurel received no egg masses. Two-way choi ce tests using paired leaves in plastic boxes showed that lar ger gree nbrier and leatherleaf leaves were preferred other smaller ones of the same species, but that leatherleaf was preferred over sheep laurel ev en when sheep laurel species were larger. These results demonstrate th at this moth exhibits oviposition preferences among plant species but that the preference hierarchy depends on the experimental situation, a nd that both the species and the size of individual leaves can be fact ors.