Shoot feeding, oviposition, and development of Monochamus galloprovincialis on Pinus pinea relative to other pine species

Abstract

Transmission of the causing agent of the pine wilt disease, Bursaphelenchus xylophilus (Steiner & Buhrer) (Nematoda: Aphelenchoididae), among Pinus pinaster Aiton (Pinaceae) trees in Portugal is known to occur during pine sawyer, Monochamus galloprovincialis (Olivier) (Coleoptera: Cerambycidae), adult feeding on twigs of healthy trees or during female oviposition on dying or dead trees. Still, the disease does not affect the other potentially susceptible local pine species, Pinus pinea L. Several experiments evaluated the suitability of P. pinea as a host for M. galloprovincialis feeding, oviposition, and progeny development. Feeding responses were studied in two-choice experiments pairing P. pinea twigs with P. pinaster, Pinus halepensis Miller, Pinus sylvestris L., Pinus uncinata Miller, and Pinus nigra Arnold. Another test assessed the effect of increased dosages of limonene applied to P. pinaster twigs on M. galloprovincialis feeding. Oviposition preferences for P. pinaster, with either intact or manipulated bark thickness, P. pinea, and P. sylvestris were also studied in two-choice tests. Finally, suitability of P. pinea as a substrate for the development of M. galloprovincialis offspring was tested. Results showed that P. pinea could be an acceptable host for the pine sawyer feeding under laboratory conditions. Only P. sylvestris and P. pinaster twigs were significantly more consumed than those from P. pinea. Control and limonene-treated twigs were eaten similarly, but feeding decreased as dose increased, suggesting an inhibitory effect of limonene. Oviposition wounds, both eggcontaining and eggless, occurred more on P. pinea than on P. sylvestris or P. pinaster, though the percentages of wounds indicating successful egg laying were significantly higher on P. pinaster and P. sylvestris. Monochamus galloprovincialis progeny completed its development on P. pinea, but emergence was lower than on P. sylvestris, likely due to higher mortality during egg and early larval stages. Thus, results on vector host preferences do not explain the observed absence of nematodekilled P. pinea trees in the field.

Combining pheromone and kairomones for effective trapping of the pine sawyer beetle Monochamus galloprovincialis

“…Interestingly, some of them resulted in lower catches than the standard lure alone; (+)-limonene in particular reduced catches by 46% and 25% in experiments in Spain and France, respectively. This result may align with hypotheses about the deterrent effect of (+)-limonene explaining the absence of infection of PWN on P. pinea in Portugal (Naves et al 2008;S anchez-Husillos et al 2013). The potentially repellent effect of this terpene therefore merits further research.…”

“…Previous experiments using the mark-release-recapture technique to study pine sawyer dispersal found that immature M. galloprovincialis adults were not caught in traps baited with the Galloprotect 2D standard lure (S anchez-Husillos et al 2015). Only mature insects (10-14 days of shoot feeding after emergence) were lured into the traps.…”

Pinus halepensis, Pinus pinaster, Pinus pinea and Pinus sylvestris Essential Oils Chemotypes and Monoterpene Hydrocarbon Enantiomers, before and after Inoculation with the Pinewood Nematode Bursaphelenchus xylophilus

“…This monoterpene hydrocarbon has been indicated as oviposition deterrent and feeding inhibitor for various conifer feeding insect species, including M . galloprovincialis …”

“…[36] This monoterpene hydrocarbon has been indicated as oviposition deterrent and feeding inhibitor for various conifer feeding insect species, including M. galloprovincialis. [37] Pinus sylvestris. Pinus sylvestris showed the highest qualitative and quantitative variation in EO composition, with a-pinene (23 -73%), b-pinene (4 -42%) and b-myrcene (2 -12%) being the healthy plants EOs main components ( Table 1).…”

Physiological development and dispersal ability of newly emerged Monochamus galloprovincialis

“…Monochamus galloprovincialis individuals used in all experiments were obtained from Pinus sylvestris Aiton (Pinaceae) logs that had been field‐colonized during the early summers of 2011, 2012, and 2013 in Tabuyo del Monte (42°15′N, 6°25′W; Castile and Leon, Spain) by wild parents attracted to the logs by commercial M. galloprovincialis lures (Galloprotect 2D, SEDQ, Barcelona, Spain). Though natural Pinus pinaster Aiton stands dominate this site, P. sylvestris was used as a host based on better breeding performance results (Sanchez‐Husillos et al., ). Colonized logs were transferred to an outdoor cage at the end of the summer, and stacked in racks until the following season.…”