Attraction of male summerform pear psylla to volatiles from female pear psylla: effects of female age, mating status, and presence of host plant

Abstract

AbstractPear psylla, Cacopsylla pyricola (Förster) (Hemiptera: Psyllidae), is a pest of pears, Pyrus L. (Rosaceae), throughout North America and western Europe. Previous studies in our laboratory showed that males of the overwintering form (winter morphotype) were attracted to volatile chemicals from pear shoots infested with post-diapause females. The current study shows that males of the summer morphotype also are attracted to volatiles from female-infested host material. Older females (8–10 d old) were significantly more attractive to males than younger (2–5 d old) females. Both virgin and mated females attracted male psylla. Volatiles from female summerforms attracted males even in the absence of host-plant material, and both living and freshly killed females were attractive. Our results indicate that female C. pyricola emit a volatile sex attractant, and the results of the studies further define the life-history conditions in female pear psylla that lead to male attraction.