Attraction of Cacopsylla pyricola (Hemiptera: Psyllidae) to female psylla in pear orchards.

The pear psylla, Cacopsylla pyricola (Förster), is a major economic pest of pears in North America and Europe. Laboratory studies have shown that males of both the summerform and winterform morphotypes in this species are attracted to volatiles given off by females. This study tested whether attraction by males to females can be shown in the field. We showed that males had a clear preference for sticky traps that had been baited with live females compared with traps baited with live males or traps that were left unbaited. Female C. pyricola did not exhibit a preference among the three types of trap treatments. These results were obtained for both morphotypes. Trap catch was also monitored at 2-h intervals to assess whether capture of males on female-baited traps varied with time of day. Summerform male C. pyricola were caught in highest numbers between 1,445 and 1,645 hours, whereas winterform males were most often captured between 1,300 and 1,700 hours on traps baited with females. In both trials, there was again a significant preference by males for the female-baited traps compared with unbaited traps. Long-term practical benefits of the methods developed here provide a platform for the development of more effective monitoring tools, use in mating disruption, or development of lure and kill technologies.