: The pine sawyer Monochamus galloprovincialis is the European vector of the recently introduced pine wood nematode. This nematode is the causal organism of pine wilt disease, a serious tree killer ...in East Asia. Efficacious baits and traps to monitor and control this beetle are now required. The effect of bark beetle (Ips spp.) pheromone components, released individually (ipsenol) or in blends (ipsenol, ipsdienol, cis‐verbenol and methyl‐butenol), together with host volatiles (turpentine or α‐pinene and ethanol) on M. galloprovincialis trap catches has been studied in Spain. A kairomonal response by male and female of M. galloprovincialis to Ips semiochemicals was found. Beetles were more attracted to host blends supplemented with bark beetle pheromones than to host volatiles alone. Ipsenol alone was attractive to pine sawyers, and was synergistic with α‐pinene and ethanol. The full blend of the four Ips semiochemicals and the host compounds was highly attractive. Multiple‐funnel traps were as effective as black cross‐vane traps in capturing this insect when the escape of trapped beetles was prevented. Trapping of non‐target bark beetle predators was also evaluated. The trogossitid Temnochila coerulea and clerid Thanasimus formicarius were kairomonally attracted to and killed in traps baited with bark beetle pheromones. These results suggest that effective monitoring of M. galloprovincialis would be possible by baiting any of these traps with host volatiles and Ips semiochemicals, but reduction of the lure components and trap modification to minimize impact on predators should be considered.
Monochamus galloprovincialis Olivier (Coleoptera: Cerambycidae) is the European vector of the pine wilt nematode, Bursaphelenchus xylophilus (Steiner and Buhrer) Nickle, which causes the pine wilt ...disease. A series of experiments were carried out to determine the existence of a contact pheromone on the female's cuticle. All males tested tried to copulate with freshly killed females, but none tried to copulate with the same females after they had been washed with hexane. When the hexane extract was reapplied to the extracted females, 50% of the males tried to copulate with them. This shows that females have a contact pheromone on their cuticle that stimulates male copulatory behavior. Cuticular compounds (mainly hydrocarbons) were sampled with solid phase microextraction and solvent extraction. No marked differences between sampling methods were observed. Individual peak analysis revealed that 23 compounds were significantly more abundant in females and eight were more abundant in males. Correspondence analysis found significant differences between the global hydrocarbon profile of male and female M. galloprovincialis. Individually, these compounds represented a small percentage of the total blend. This suggest that males of M. galloprovincialis may distinguish females by a blend of several, not very abundant, compounds that are present in both sexes but in different proportions.
Developmental thresholds and thermal requirements for development of post-dormancy larvae of
Monochamus galloprovincialis
(Olivier) (Cerambycidae; Monochamini) were studied at ten constant ...temperatures ranging from 7 to 35°C. The relationship between temperature and development duration in days was linear between 15 and 30°C (
r
2
= 0.98). The lower threshold for development was determined to be 12.2 ± 0.8°C and an average of 822 degree-days (DD) above that value was required for 50% adult emergence under laboratory conditions. The rate of larval development decreased above 30°C and the lethal upper threshold was between 32 and 35°C. Degree-day rate summation was initiated in the first of March and model predictions were validated with records of field emergence for the years 2001 to 2004. The modified sine wave predicted median emergence with an average error of 3.8 days from emergences in the field and a zero-day difference for two of the years. Model predictions were always within 10% of actual observed emergences. Predictions for early emergences (cumulative percentiles 1 and 10) were less accurate than predictions for median and late emergencies. The results suggest that a simple linear method driven by air temperatures can predict the emergence of
M
.
galloprovincialis
with sufficient accuracy to improve the pest management programmes currently implemented on the pine wilt disease affected zone in Portugal.
Monochamus galloprovincialis (Coleoptera, Cerambycidae) is the vector of the Pine Wood Nematode (Bursaphelenchus xylophilus) in Europe. This nematode is the agent of the Pine Wilt Disease (PWD), a ...syndrome causing important damages in Eurasian pine forests. We report here the development of 12 polymorphic microsatellites loci specific to this species. We observed a moderate allelic richness over all loci. The number of allele per locus ranked from 2 to 8, with an average of 3.75. These markers will help to characterize the effect of the spread of an invader on the genetic structure of a native vector species.
•The study aimed at clarifying basic life traits (fecundity, mortality and development) of
Monochamus galloprovincialis
, the vector of
Bursaphelenchus xylophilus
, the causative agent of the Pine ...Wilt Disease, in Portugal.
• Mating and oviposition experiments were conducted on
P. sylvestris
logs under laboratory conditions during two years. Larval development was followed outdoors.
• Fecundity was high, with 138.2 eggs per female.
• For the first time, the number of larval instars (4) in
M. galloprovincialis
was recognized and instars were described.
• Informations are provided on the shape and size of the larval galleries. Boring of galleries in sapwood and heartwood started at the third instar. All instars could overwinter but adults emerged simultaneously resulting in a univoltine life cycle for the majority of the individuals.
• An obligatory diapause in the forth instar was assumed. However, 8.1% of the insects had a two year development.
• Important differences in mortality were noted between the two experimental years, which could be explained by differences on the size of the breeding logs.
• There is a high biological proximity between
M. galloprovincialis
populations in France and those in Portugal and Northern Europe. However, a higher fecundity and longevity was observed in France, as well as a higher percentage of insects with a two year development, compared with portuguese populations.
Abstract
Bursaphelenchus xylophilus is an invasive pest of pines. When introduced
accidentally into a new geographic area, it will share the same ecological
niche as the closely related indigenous ...species, B. mucronatus. Competition
between native and introduced species may affect the spread of invasive
species, so we investigated the possible competitive interaction between
these two nematode species transmitted by the same insect-vector, Monochamus
galloprovincialis. In order to understand how the two species interacted, we
compared, under laboratory conditions, their growth on fungi and pines,
their ability to board M. galloprovincialis, and their competitive
interaction in situations of double boarding. Bursaphelenchus xylophilus
showed greater rates of growth than B. mucronatus in single and mixed
treatments. The invasive species was competitively superior to the
indigenous species in mixed treatments (fungi and pines). This competitive
advantage in pines, prior to the beetles' infestation, could explain the
greater abundance of the invasive (68%) species over the indigenous in the
insect vector M. galloprovincialis. The indigenous species had no effect on
beetle boarding of the invasive species. The occurrence of B. mucronatus in
France and its wide distribution on numerous pine species could have an
effect on B. xylophilus invasion in the initial steps of an invasion
process. Nevertheless, due to the superior competitiveness of B. xylophilus,
we cannot state that B. mucronatus will be efficient as a factor to decrease
propagation of this invasive species.
Following a request from European Commission, the PLH Panel examined the comments of the Portuguese plant health authorities on a previous EFSA opinion with regard to pine wood nematode (PWN) and ...Pinus pinea and a report on PWN surveys in Portugal. Regarding the comment, based on behavioural responses of PWN to CO2 and to ß‐myrcene, that Monochamus galloprovincialis can feed on P. pinea without implying PWN infestation, the Panel noted the uncertainties on how chemical attraction influences the exit of PWN from the vector. The Panel agreed that P. pinea is not a preferred breeding host of M. galloprovincialis, but it noted the evidence from Italy of breeding of M. galloprovincialis in fallen woods of P. pinea, suggesting P. pinea to be an occasional host. The Panel agreed that, although pathogenicity of PWN has been recorded on P. pinea in inoculation experiments on small plants, this does not necessarily relate to pathogenicity on larger trees in the field. The additional information on Portuguese PWN surveys is not sufficient to conclude that P. pinea is resistant to PWN. The Panel also noted that asymptomatic infestations by PWN are well known in other areas, and pine species considered tolerant to PWN could still maintain it at low levels in restricted parts of a tree. The Panel concluded that there is high uncertainty concerning the classification of the risk of spread of PWN with plants and wood of P. pinea, owing to the scarcity of information on the interaction of M. galloprovincialis, PWN and P. pinea, as well as on the field resistance of P. pinea to PWN. Owing to high uncertainty related to the host potential of P. pinea, more studies on the transmission of PWN at feeding wounds and on its survival in trees and wood of P. pinea are needed.
The attractiveness of different combinations of volatile compounds to several scolytid and cerambycid species, potential vectors of phytoparasitic nematodes of the genus
Bursaphelenchus
Fuchs, was ...investigated in pine woods of central Italy. The blend composed of α-pinene, ethanol, ipsenol, ipsdienol and 2-methyl-3-buten-2-ol was very efficient in trapping the cerambycids
Monochamus galloprovincialis, Acanthocinus griseus
and
Arhopalus syriacus
and the scolytids
Ips sexdentatus, Orthotomicus erosus
and
Hylurgus ligniperda
. This blend is proposed for operational surveys of
Bursaphelenchus
spp
.
associated with these beetles. Comparison of the capture levels with cross-vane and funnel traps baited with α-pinene, ethanol, ipsenol, ipsdienol, 2-methyl-3-buten-2-ol and
cis
-verbenol revealed the higher efficacy of the cross-vane traps for the above-mentioned cerambycids and the scolytid
I. sexdentatus
but greater effectiveness of the funnel traps in capturing
H. ligniperda
and
O. erosus.
Cross-vane traps were more efficient in capturing large numbers of these insects. Data on non-target xylophagous beetles and predator species are also reported.
The pine sawyer Monochamus galloprovincialis (Olivier) is the vector of the introduced pine wood nematode Bursaphelenchus xylophilus (Steiner & Bührer) Nickle in Portugal, and until recently was ...considered a secondary forest insect. Under laboratory conditions, a study of biological and reproductive traits of 37 insect pairs was conducted. The longevity of both sexes was similar, being 61.2±6.5 days for males and 64.0±6.3 days for females (mean±SE). Sixteen small-sized insects (22% of the population) died within 20 days and before starting to reproduce. The sexual maturation period (without egg laying) was 20.4±0.7 days (mean±SE), while the oviposition period lasted 54.0±4.2 days (mean±SE). The oviposition rate increased very quickly during the first weeks of life, peaking to almost two eggs per day during days 30–44, and gradually dropping in the following weeks. The females laid an average of 67.0±5.96 (mean±SE) eggs through their lives. The hatch rate was 92.6±1.0%; (mean±SE). There were large individual variations in longevity and fecundity parameters, and principal component analysis based on 16 morphological and biological parameters separated the breeding insects into four distinct groups. Almost half of the reproducing beetles were large-sized insects, with high longevity and fecundity traits. Overall, the reproductive potential of the Portuguese population of M. galloprovincialis seems to be smaller than that described for other Monochamus vectors of the pine wood nematode both in North America and Japan.
The study of the life history dynamics of the pine sawyer beetle Monochamus galloprovincialis (Olivier) is important because the beetles vector the pinewood nematode. The objectives of this study ...were to investigate differences in beetle life history parameters between the two common host tree species in Turkey, Pinus sylvestris and Pinus nigra. Relationships between the number of oviposition sites, holding time (time between log cut and oviposition), log moisture content, log volume and area, and adult survivorship were evaluated. No significant differences were found between the two tree species except adult density per m². The holding time did not influence the number of oviposition sites, larval entry holes or adults for P. sylvestris. There was a negative correlation between the holding time and the number of oviposition sites for P. nigra. The number of adults emerged per log was correlated with the number of larval entry holes only for P. sylvestris. Only 12 and 15% of the initial cohort completed development and emerged as adults for P. sylvestris and P. nigra, respectively. Both tree species are equally suitable hosts for M. galloprovincialis development. We conclude that the high within-log mortality of beetles is a combination of resource quality and quantity factors and intraspecific competition and cannibalism during larval development.
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