Response ofMatsucoccus thunbergianae males to synthetic sex pheromone and its utilization for monitoring the spread of infestation
Attraction of (2E,4E,6R,10R)-4,6,10,12-tetramethyl-2,4-tridecadien-7-one [1; (6R,10R)-matsuone] and its antipode [2; (6S,10S)-matsuone] toMatsucoccus thunbergianae males was studied in the laboratory and in the field. They showed stronger response to1. In laboratory bioassays, the threshold concentrations for male attraction with1 and2 were 16 fg and 150 pg, respectively. In the field, during the first two days after traps were set, traps baited with 50 µg of1 on rubber septa or filter paper rolls caught more males than control traps. Between the sixth day and the tenth day after traps were set, in a daily trap catch experiment, the traps with 50 µg of1 on filter paper rolls caught more males than control traps on one day only, whereas those on rubber septa were always effective. The shape of the traps did not affect male catches. Males were caught on pheromone traps in locations where no scales were found by the customary detecting procedures.
Attraction of male summerform pear psylla to volatiles from female pear psylla: effects of female age, mating status, and presence of host plant
Abstract Pear 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. Résumé Le psylle du poirier, Cacopsylla pyricola (Förster) (Hemiptera: Psyllidae), est un ravageur du poirier dans toute l’Amérique du Nord et l’Europe de l’Ouest. Des études antérieures dans notre laboratoire ont montré que les mâles de la forme hivernante (morphotype d’hiver) sont attirés par les substances volatiles émises par les pousses de poiriers infestées par des femelles au stade post-diapause. La présente étude montre que les mâles du morphotype d’été sont aussi attirés par les substances volatiles émises par les plantes hôtes infestées par les femelles. Les femelles plus âgées (8–10 j d’âge) sont significativement plus attirantes pour les mâles que les femelles plus jeunes (2–5 j d’âge). Tant les femelles vierges que les accouplées attirent les psylles mâles. Les substances volatiles émises par les femelles de la forme d’été attirent les mâles, même en l’absence de tissus de la plante hôte; de même, les femelles vivantes et celles qui sont fraîchement tuées sont attirantes. Nos travaux indiquent que les femelles de C. pyricola émettent une substance attractive sexuelle volatile et ils déterminent les conditions du cycle biologique des femelles du psylle du poirier qui provoquent l’attraction des mâles. [Traduit par la Rédaction]
Assignment of (6R*,10R*)-relative stereochemistry to the major component of the sex pheromone of the maritime pine scale, matsucoccus feytaudi
Abstract (2 E ,4 E ,6 R ,10 S )-4,6,10-Trimethyl-2,4-dodecadien-7-one 1 and its (6 S , 10 S )-isomer were synthesized. The 1 H NMR spectrum of (6 S , 10 S )- 1 coincided with that reported for the major component of the sex pheromone of Matsucoccus feytaudi , which must therefore be either (6 S , 10 S )- or (6 R , 10 R )- 1 .