RESPONSES OF CONOPHTHORUS SPP. (COLEOPTERA: SCOLYTIDAE) TO BEHAVIORAL CHEMICALS IN FIELD TRIALS: A TRANSCONTINENTAL PERSPECTIVE

Abstract

The Canadian Entomologist 132: 925 -937 (2000) We tested six behavioral chemicals, pityol, conophthorin, 4-allylanisole, verbenone, 2-hexenol, and a-pinene, in a series of field trials directed at six combinations of Conophthorus Hopkins -Pinus L. spp. (Pinaceae) Ait. trans-Verbenol was tested only on C . resinosae on P. resinosa. Traps baited with pityol caught more beetles than unbaited traps in nearly all of the assays, and conophthorin consistently inhibited male beetle response to pityol for all species tested. Behavioral responses of species of Conophthorus to a-pinene appeared to parallel host phylogeny, inasmuch as beetles using Haploxylon pines as hosts utilized a-pinene as a synergist for the beetle-produced pityol, whereas beetles using Diploxylon pines as hosts did not. a-Pinene was a synergist for pityol in C . ponderosae on P. monticola and C. coniperda on P. strobus, but not for species of Conophthorus on any other pines tested. Conophthorus ponderosae on P. ponderosa was the only beetle-host combination tested where verbenone was a synergist for pityol, but this effect was not consistent in all years of testing. It was also the only beetle-host combination in which 4-allylanisole was a repellent. For all otherAuthor to whom all correspondence should be addressed (E-mail: nrappaport@fs.fed.us). THE CANADIAN ENTOMOLOGISTNovemberPecember 2000 beetle-host combinations, verbenone was neutral to slightly repellent and 4-allylanisole was either synergistic or neutral in pityol-baited traps. Promising synergists and intermptants/repellents were identified for implementation in pestmanagement regimes, including conophthorin as an interruptant for all species of Conophthorus tested, 4-allylanisole as an interruptant for C. ponderosae on P . ponderosa, a-pinene as a synergist for pityol in all species tested on Haploxylon pines, and 4-allylanisole as a synergist for pityol in C. conicolens and C. coniperda. ResumeNous avons test6 six substances chimiques affectant le comportement, le pityol, la conophthorine, le 4-allylanisole, la verbhone, le 2-hexenol, et l'a-pinkne, au cours d'une sCrie de tests en nature sur six combinaisons de Conophthorus Hopkins -Pinus spp. (Pinaceae) en plusieurs endroits rkpartis dans toute 1'AmCrique du Nord. Les combinaisons colCoptkre -arbre-h8te ont Ct C les suivantes: Conophthorus ponderosae Hopkins sur Pinus ponderosa Laws., C. ponderosae sur Pinus monticola Dougl., Conophthorus conicolens Wood sur Pinus pseudostrobus Lindl., Conophthorus teocotum Wood sur Pinus teocote Schl. et Cham., Conophthorus coniperda (Schwarz) sur Pinus strobus L. et Conophthorus resinosae Hopkins sur Pinus resinosa Alt. Le trans-verbCnol a Ct C test6 seulement sur C. resinosae sur P. resinosa. Les pikges garnis de pityol ont capturC plus d'insectes que les pikges non garnis dans presque tous les tests et la conophthorine inhibait systkmatiquement la rCponse des miiles au pityol chez toutes les espkces testkes. La rCponse de toutes les espkces de Conophthorus a l'a-pinkne semble fonction d...

Bark Beetles Control in Forests of Northern Spain

“…The name conophthorin comes from the genus Conophthorus, that includes species known to produce it with an inhibitor effect to aggregation pheromones or host kairomones, that is, Conophthorus coniperda (Birgersson et al 1995;de Groot et al, 1998, Rappaport et al, 2000 and C. resinosae Rappaport et al, 2000). In addition, there are several studies about the repellent effect of (E)-(-)-conophthorin and racemic conophthorin to pheromone baited traps in bark beetles species that are not known to produce it, as seen in Xylosandrus germanus (Kohnle et al 1992), Dendroctonus ponderosae (Huber et al, 1999), D. pseudotsugae (Huber et al, 1999(Huber et al, , 2000(Huber et al, , 2001, Dryocoetes confusus (Huber et al, 2000) Pityophthorus setosus (Dallara et al, 2000), C. cornicolens and C. teocotum (Rappaport et al 2000), I. pini (Huber et al, 2000(Huber et al, , 2001, I. duplicatus , I. sexdentatus (in France) (Jactel et al, 2001) and I. typographus (Zhang & Schlyter, 2003). In spite of this fact, there are reports referring to conophthorin as attractant as well, according to results observed in I. mexicanus, Lasconotus pertenuis (Coleoptera: Colydiidae) and P. carmeli (Dallara et al 2000) and in Epuraea thoracica (Coleoptera: Nitidulidae) (Kohnle et al, 1992).…”

Effects of Verbenone Dose and Enantiomer on the Interruption of Response of the Red Turpentine Beetle, <I>Dendroctonus valens</I> LeConte (Coleoptera: Scolytidae), to Its Kariomones

“…At higher concentrations, it served to balance the sex ratio of attacking beetles (Renwick andVité 1969, Payne et al 1978), whereas very high amounts inhibited attacks by both sexes. Verbenone synergized the attractiveness of pityol to Conophthorus ponderosae Hopkins at some release rates (Rappaport et al 2000). Verbenone also interrupted the attraction of the bark beetles D. ponderosae, D. brevicomis, Ips latidens, and Ips pini to their aggregation pheromones in a dose-dependent fashion (Paine andHanlon 1991, Miller et al 1995).…”

Disruption of trans‐pityol‐mediated attraction by racemic trans‐conophthorin in twig beetle Pityophthorus pubescens

“…1995; Dallara et al. 2000; de Groot and DeBarr 2000; Rappaport et al. 2000) and other xylophagous insects (Morewood et al.…”

“…Moreover, trans-conophthorin has also been isolated in aerations, and from the hindguts of males, of the closely related species Conophthorus coniperda (Schwarz 1895) and it was named after this genus (Birgersson et al 1995). Its biological activity in bark beetles (Kohnle et al 1992;Birgersson et al 1995;Pierce et al 1995;Dallara et al 2000;de Groot and DeBarr 2000;Rappaport et al 2000) and other xylophagous insects (Morewood et al 2003) has been widely reported. In almost all cases, ())-trans-conophthorin acts as a repellent or disruptant, with the exception of the twig beetle Pityophthorus carmeli Swaine 1918.…”