Oviposition preference and larval survival of Diprion pini on Scots pine clones in relation to foliage characteristics

1 When laying eggs, adult female Diprion pini discriminated between clones of Scots pine, Pinus sylvestris. 2 Larval survival was affected by Scots pine clone but was not correlated with oviposition preference. 3 Diprion pini laid most eggs on tougher needles of Scots pine. 4 There was no evidence to suggest that D. pini is responding to the monoterpene composition of the foliage.     

Bark beetle and woodborer responses to stand thinning and prescribed fire in northeastern US coastal and inland pitch pine barrens

1. Southern pine beetle, Dendroctonus frontalis, has expanded its range further into the northeastern United States. This expansion threatens rare and ecologically valuable interior and coastal pitch pine barrens.
2. Pitch pine barrens restoration and southern pine beetle infestation suppression often involve leaving downed dead wood that saproxylic insects can exploit.
3. Semiochemical-baited traps were used to investigate the response of bark beetles and woodborers to restoration treatments at Rocky Point State Forest and the Albany Pine Bush Preserve, examples of coastal and interior pitch pine forests, respectively.
4. A total of 29,598 saproxylic insects from 116 species of bark beetles and woodborers were captured at Rocky Point State Forest, while 23,117 individuals from 67 species were captured at Albany Pine Bush Preserve.
5. Ips spp. were abundant at both sites with 28%–47% and 42%–74% of total collections at Rocky Point State Forest and Albany Pine Bush Preserve, respectively.
6. Ips grandicollis did not respond to treatments at either site. However, Ips pini was found in higher numbers in thinned blocks in Rocky Point State Forest.

     

Growth and reproduction of aphids and levels of free amino acids in Scots pine and Norway spruce in an open-air fumigation with ozone

To estimate the susceptibility of conifer seedlings to aphids under future tropospheric ozone levels, Scots pine (Pinus sylvestris L.) and Norway spruce (Picea abies (L.) Karst.) seedlings were exposed to ambient and elevated ozone levels in an open-air exposure system. Growth and reproduction of the aphids Schizolachnus pineti and Cinara pinea on Scots pine and Cinara pilicornis on Norway spruce were monitored. Levels of free amino acids in foliage and young shoots were used as indicators of host plant quality. In elevated treatment plots the ozone doses were between 1.2 and 1.7 times the dose in ambient plots in 1990–93. Half of the seedling material in 1992–93 was subjected to nitrogen fertilization treatment to evaluate the effects of increased N deposition. In 1990, population density of S. pineti on pine did not differ between ambient and elevated ozone treatments during growing season, but remained higher in the elevated ozone plot than in the ambient plot at the end of the growing season. This was associated with elevated levels of glutamic acid in foliage. In August 1992, the numbers of S. pineti were consistent between the two ambient ozone plots, but deviated highly between the two ozone-fumigated plots. Glycine concentration in pine foliage was elevated by ozone, but free amino acid concentrations were not related to aphid performance. In 1993, ozone and nitrogen did not significantly affect the relative growth rate (RGR) of S. pineti or C. pinea nymphs on Scots pine, but glutamic acid concentration in foliage was increased by nitrogen fertilization. On Norway spruce, fecundity of C. pilicornis females was higher in elevated ozone treatment, but RGR of nymphs was not affected in 1992. In 1993, RGR of C. pilicornis nymphs was increased by nitrogen fertilization in June, but not affected by ozone. Nitrogen fertilization increased the levels of total free amino acids, aspartic acid, glutamic acid and proline in elongating shoots of Norway spruce, and ozone reduced the concentrations of valine and γ-butyric acid. Our results suggest that availability of nitrogen from soil has a stronger impact on the concentrations of free amino acids in conifer seedlings than ozone. Some episodes of high ozone concentration may increase free amino acids in foliage. Aphid response to ozone was extremely variable, in agreement with previous laboratory experiments. The expected 20–70% increase in ambient concentrations of tropospheric ozone may in some occasions enhance aphid performance on Scots pine and Norway spruce seedlings, but in most cases the ozone effect on the susceptibility of conifer seedlings to sucking insect pests is not important.     

Origin and dispersal of Potamophylax cingulatus (Trichoptera: Limnephilidae) in Iceland

相似文献   

Performance of the tree‐killing bark beetles Ips typographus and Pityogenes chalcographus in non‐indigenous lodgepole pine and their historical host Norway spruce

相似文献   

Variation in needle terpenoids among Pinus sylvestris L. (Pinaceae) provenances from Turkey

Variation of terpenes and resin acids in needles of young Scots pine (Pinus sylvestris L.) seedlings from nine different provenances in Turkey was investigated. The provenances represent 1200-km West to East and 400-km South to North transects. Seven monoterpenes and two sesquiterpenes were reported in the needles of pines studied. Generally, the kinds of terpenes were similar but the relative amount of some compounds differed among the origins. The major components of the monoterpene fraction in Turkish sources were α-pinene (84.8%), β-pinene (4.1%) and limonene (3.0%), corresponding to 91.9% of the crude needle extract. In a PCA-analysis, 3-carene, myrcene and terpinolene in seedlings from Turkish provenances were quite low and thus, they were clearly different from a Northern European Scots pine provenance from Finland. In the resin acid fraction, abietic acid (62.4%) and dehydroabietic acid (16.1%) were the most abundant constituents in the needles of the Scots pine from Turkish provenances.     

Location,but not defensive genotype,determines ectomycorrhizal community composition in Scots pine (Pinus sylvestris L.) seedlings

1. For successful colonization of host roots, ectomycorrhizal (EM) fungi must overcome host defense systems, and defensive phenotypes have previously been shown to affect the community composition of EM fungi associated with hosts. Secondary metabolites, such as terpenes, form a core part of these defense systems, but it is not yet understood whether variation in these constitutive defenses can result in variation in the colonization of hosts by specific fungal species.
2. We planted seedlings from twelve maternal families of Scots pine (Pinus sylvestris) of known terpene genotype reciprocally in the field in each of six sites. After 3 months, we characterized the mycorrhizal fungal community of each seedling using a combination of morphological categorization and molecular barcoding, and assessed the terpene chemodiversity for a subset of the seedlings. We examined whether parental genotype or terpene chemodiversity affected the diversity or composition of a seedling''s mycorrhizal community.
3. While we found that terpene chemodiversity was highly heritable, we found no evidence that parental defensive genotype or a seedling''s terpene chemodiversity affected associations with EM fungi. Instead, we found that the location of seedlings, both within and among sites, was the only determinant of the diversity and makeup of EM communities.
4. These results show that while EM community composition varies within Scotland at both large and small scales, variation in constitutive defensive compounds does not determine the EM communities of closely cohabiting pine seedlings. Patchy distributions of EM fungi at small scales may render any genetic variation in associations with different species unrealizable in field conditions. The case for selection on traits mediating associations with specific fungal species may thus be overstated, at least in seedlings.

     

Characterization of the ascomycetes Therrya fuckelii and T. pini fruiting on Scots pine branches in Nordic countries

The relative frequency of Therrya fuckelii and T. pini fruiting on dead branches of Scots pine was investigated in southern Norway by examining lightning-damaged and wind-fallen trees, randomly collected branches and Nordic herbarium collections of these ascomycetes representing the order Rhytismatales. Ascus, ascospore, and subhymenium characteristics were used as criteria for species identification, while a sequence analysis of ITS rDNA gene cluster was performed to compare the relatedness of the species to each other and to corresponding fungal sequences available at the NCBI GenBank Sequence Database. In a few cases, the two Therrya species co-occurred on the same branch, but in general, whether field or herbarium material, T. fuckelii was clearly more common than T. pini. Within the Nordic countries, both species occurred throughout the natural distribution area of Scots pine. The ITS rDNA sequence of T. pini strains was 91% similar to T. fuckelii strains, the differences locating both within the internal transcribed spacers ITS1 and ITS2 and the 5.8 S rDNA gene. More variation in the ITS1-5.8S-ITS2 sequence was observed among T. pini than T. fuckelii samples; genetic implications of this finding are discussed. Upon sequence analysis, we discovered that a T. pini sequence has been deposited in the NCBI GenBank under a false identity. We emphasize the importance of co-examining strains that originate from mature fruit bodies with fully developed morphologic features as reference samples.     

Ectomycorrhization of Tricholoma matsutake and two major conifers in Finland—an assessment of in vitro mycorrhiza formation

This study aimed to test the ability of Tricholoma matsutake isolates to form mycorrhizas with aseptic seedlings of Pinus sylvestris L. and Picea abies (L.) Karst. Germinated seedlings of Scots pine and Norway spruce were separately inoculated with either isolates originating from Finland or Japan. Eight months after inoculation, the Finnish isolate had formed a sheath and Hartig net on both host species. Ectomycorrhizal Scots pine seedlings inoculated with the Finnish isolate showed the same shoot height and dry mass as the controls. Ectomycorrhizal Norway spruce seedlings inoculated with the Finnish isolate had similar shoot height but slightly less dry mass than the control seedlings. For both tree species, inoculation with the Finnish isolate resulted in reduced total nitrogen content per seedling, but carbon content was unaffected. Inoculation with the Japanese isolate resulted in an initial Hartig net-like structure in pine but not in spruce. No typical Hartig net was observed on either tree species. Furthermore, seedlings of both species inoculated with the Japanese isolate showed significantly reduced growth, dry mass, nitrogen, and carbon content per seedling and shoot height (in spruce) compared to the controls. This study documents and describes the in vitro ectomycorrhization between T. matsutake and Scots pine or Norway spruce and the variable mycorrhizal structures that matsutake isolates can form.     

Effectiveness of different lures for attracting Ips acuminatus (Coleoptera: Curculionidae: Scolytinae)

1. Ips acuminatus (the sharp-toothed bark beetle, STBB) is currently considered to be one of the most serious pests of Scots pine in many European countries. STBB management is among the most challenging tasks in pine forests; the development of methods for monitoring, predicting and managing outbreaks of this bark beetle is therefore crucial.
2. Pheromone-baited traps have been widely recommended as a valuable tool for the monitoring and mass trapping of bark beetles. Although different suppliers offer a variety of STBB lures, their effectiveness has rarely, if ever, been evaluated under natural conditions.
3. We evaluated the attractiveness of three commercially available and five experimental synthetic lures by comparing the numbers of STBBs captured in white, six-funnel traps. The studies were conducted in 2017–2019 in Poland, in Scots pine-dominated forests affected by STBB outbreaks.
4. Our study demonstrated significant differences in the effectiveness of the lures. The experimental lure produced by the Witasek company (Austria) and the recently marketed lure Acumodor Micro from Chemipan (Poland) were the most attractive to STBB. Among the least effective were two commercial lures (Acuwit and Acumodor), hitherto used in Central Europe.
5. The results will be useful in developing methods for the monitoring and management of STBB populations.

     

A comparison of Northeast Atlantic killer whale (Orcinus orca) stereotyped call repertoires

Killer whale call repertoires can provide information on social connections among groups and populations. Killer whales in Iceland and Norway exhibit similar ecology and behavior, are genetically related, and are presumed to have been in contact before the collapse of the Atlanto-Scandian herring stock in the 1960s. However, photo-identification suggests no recent movements between Iceland and Norway but regular movement between Iceland and Shetland. Acoustic recordings collected between 2005 and 2016 in Iceland, Norway, and Shetland were used to undertake a comprehensive comparison of call repertoires of Northeast Atlantic killer whales. Measurements of time and frequency parameters of calls from Iceland (n = 4,037) and Norway (n = 1,715) largely overlapped in distribution, and a discriminant function analysis had low correct classification rate. No call type matches were confirmed between Iceland and Norway or Shetland and Norway. Three call types matched between Iceland and Shetland. Therefore, this study suggests overall similarities in time and frequency parameters but some divergence in call type repertoires. This argues against presumed past contact between Icelandic and Norwegian killer whales and suggests that they may not have been one completely mixed population.     

Relationship of aluminium and calcium to net CO2 exchange among diverse Scots pine provenances under pollution stress in Poland

Light-saturated net photosynthesis (A_sat), dark respiration (RD), and foliar nutrient content of eight European Scots pine (Pinus sylvestris L.) provenances were measured at experimental sites in western Poland. Two-year-old seedlings were planted in 1984 at two sites with similar soils in areas of contrasting air pollution. One site was near a point source of SO₂ and other pollutants, and another 12 km to the southeast in an area free of acute air pollution was treated as a control. The eight provenances were from a large north-tosouth latitudinal range (60 to 43° N). At the heavily polluted site Scots pine trees exhibited lower growth rates and crown dieback and deformation. Soil pH, Ca and Mg were at least 10 times lower, and Al 10 times higher at the polluted than the control site. In 1991, concentrations of Al, P, Ca, S, Mn, Fe, and Zn in oneyear old Scots pine foliage were higher and Mg lower at the polluted than control site. At both sites foliar Mg levels were within the range considered deficient (0.6 mg g^-1), and at the polluted site, Al concentrations were very high (670 to 880 g g^-1). In all provenances, RD of one-year-old needles was higher (by 22% on average) and A_sat was lower (by 37% on average) at the polluted than the control site. The ratio of A_sat: RD was half as great in all provenances at the polluted (4 to 6) than control site (8 to 11). Provenances of southern origin had greater increases in RD and water-use efficiency at the polluted site than other provenances. Within the polluted site alone, or across both sites, A_sat in Scots pine was negatively correlated to the Al: Ca ratio (p<0.001, r=–0.93). Across sites RD increased with needle N and Al (multiple regression, p<0.001). The data suggest that at the polluted site there is excessive soil Al and deficient Mg availability, low needle Mg and high Al concentrations and high Al: Ca ratios, and that these have resulted in reduced photosynthetic capacity and increased respiration.     

Hide and seek in forests: colonization by the pine processionary moth is impeded by the presence of nonhost trees

• 1 The disruption of host‐finding cues has been proposed as a key mechanism underlying the lower damage caused by phytophagous insects in mixed forests. We tested this hypothesis by investigating the distribution of pine processionary moth Thaumetopoea pityocampa (Denis & Schiffer‐Müller) (Lepidoptera) infestation at the edges of pure stands of Pinus pinaster (AÏton) at some distance from nonhost trees (Experiment 1) or bordered in part by a broadleaved hedgerow (Experiment 2).
• 2 An ‘edge effect' was demonstrated, with trees at the edge of the stand being more heavily infested than those at the interior of the stand.
• 3 The presence of a nonhost broadleaved hedgerow in front of the edge of the pine stand resulted in lower T. pityocampa infestation. There were significantly fewer T. pityocampa nests behind the hedgerow than on the exposed part of the edge. The presence of the hedgerow did not dilute or repel T. pityocampa infestation further into the pine stand, although it decreased the infestation of T. pityocampa throughout the pine stand. The decrease in T. pityocampa infestation behind the hedgerow was greater when the broadleaved hedgerow was taller than the pine trees.
• 4 These results highlight the benefits of using nonhost tree species on the edge of monospecific forest stands to reduce insect damage. This approach could be promoted as an innovative forest pest management method.

     

Differential impacts of long-term (CO<Subscript>2</Subscript>) and O<Subscript>3</Subscript> exposure on growth of northern conifer and deciduous tree species

The long-term effects of elevated CO₂ and CO₂+O₃ concentrations on the growth allocation in northern provenances of Norway spruce [Picea abies (L.) Karst.], Scots pine [Pinus sylvestris (L.)] and pubescent birch clones (Betula pubescens Ehrh.) were examined in open-top chambers after a 4-year-long experiment. The total biomass responses of the tree seedlings to increased CO₂ and CO₂+O₃ concentrations were not statistically significant and varied between the provenances and species. The seedlings of northern origin were the least sensitive in their response to treatments. The total biomass of the Norway spruce seedlings slightly decreased in response to CO₂ in three provenances. Scots pine from the local provenance had a slight biomass increase after elevated CO₂+O₃ treatment. The slower-growing birch clone seemed to benefit from elevated CO₂, whereas in the faster-growing clone, reductions in biomass accumulation were seen. The combined CO₂+O₃ treatment reduced the positive effects of elevated CO₂, especially in the slower-growing birches. Observations of significant effects were limited to a few parameters. Carbon dioxide treatment decreased needle dry weight of Norway spruce in one northern provenance. The needle and wood dry weight increased (CO₂ + O₃) in local Scots pine. Significant birch response was limited to increased fine root density (O₃ + CO₂) in the inland clone. The diverse effects of elevated CO₂ and CO₂ +O₃ on seedling growth and biomass provide evidence that exposure of northern trees to the enhanced variable CO₂ and O₃ concentrations of the future will have varied effects on the growth of these species. The direction and magnitude of those effects will differ depending on species and origins.     

Potential damage by Acromyrmex ant species in pine plantations in southern Brazil

1. Acromyrmex species primarily attack Pinus taeda plantations during the first months after planting, with more intense damage in the first 30 days.
2. We evaluated potential damage by Acromyrmex crassispinus and Acromyrmex subterraneus in 30-day-old P. taeda plantations in southern Brazil by assessing the number of attacked plants and the distance reached by each colony, along with the losses in plant development resulting from different levels of defoliation.
3. Both species were significant pests in newly established pine plantations. A single colony can attack a substantial number of seedlings (up to 453 seedlings). Colonies with larger nests attacked more plants and ranged farther; A. crassispinus reached 59 m and A. subterraneus 87 m.
4. After 10 years, no significant losses in plant development were seen in seedlings defoliated less than 50% at 30 days after planting. But when defoliation of the young plants attained 75%, 100%, and 100%, including the cut of the apical meristem, volume losses reached 32%, 37%, and 43%, respectively.
5. Leaf-cutting ant controls should be carried out in plantations of P. taeda within 30 days of planting to avoid attacks. When seedlings are defoliated more than 75%, they should be replanted to avoid future losses in final wood volume.

     

A review of ozone responses in Scots pine (Pinus sylvestris)

The data on Scots pine responses to elevated ozone (O₃) mainly come from experimental studies with young seedlings and trees. Based on the 38 experiments reviewed here, Scots pine may be considered as an O₃-sensitive conifer species, with mature pines more sensitive than younger trees. This is due to their relatively small proportion of current (c) year needles with the highest photosynthetic capacity. Moreover, young seedlings and trees seem to acclimate to slightly elevated realistic O₃ exposures, and hence do not often exhibit growth and biomass reductions in spite of the visible and microscopic needle injuries and changes in needle chemistry. The O₃ sensitivity in Scots pine is thought to relate to impaired water status due to the malfunction of stomata and subsequent increase in transpiration. This may lead to reduced wood biomass in the long term, if Scots pines try to maximise the biomass of c needles and root biomass to maintain efficient water and nitrogen (N) supply to support the photosynthesis of c needles. Tree water status also contributes to the spring-time recovery of photosynthesis. We call especially for studies on atmosphere–needle surface interaction that would yield novel information on the impact of O₃ on epicuticular waxes and stomatal functioning, which both regulate O₃ flux and tree water status and hence also modify photosynthesis. The need for flux-based field studies is especially important in the light of future climatic change, since the risk presented by O₃ to Scots pine forests in Northern and Central Europe seems to be equal.     

The effect of open-air fumigation with SO2 and O3 on carbohydrate metabolism in Scots pine (Pinus sylvestris) and Norway spruce (Picea abies)

The carbohydrate metabolism of the needles of Scots pine (Pinus sylvestris) and Norway spruce (Picea abies) has been examined in trees that were exposed to SO₂, and O₃, in an open-air fumigation experiment located in the Liphook forest in southern England. Two-year-old seedlings were planted in 1985 in seven experimental plots. Five plots received fumigation treatments of SO₂, O₃ or a combination of these gases to give a 2 × 3 factorial design with one additional ambient plot Fumigation with SO₂, occurred from May 1987 to December 1990 and O₃, fumigation occurred from March to December 1988, May to December 1989 and February to December 1990. Five samples of needles for investigation of carbohydrate metabolism were taken between February and July 1989. The concentrations of soluble carbohydrates (including sucrose and hexoses) were greatly reduced in the needles taken from Scots pine growing in the treated plots, and were also reduced, but to a lesser extent, in the needles taken from Norway spruce. Little variation in the concentration of starch in the needles of either species was detected. The activities of the two final enzymes of sucrose synthesis, sucrose phosphate synthase and sucrose 6-phos-phate phosphatase, were greatly reduced in the needles of Scots pine and were also reduced, but to a lesser extent, in the needles of Norway spruce in the fumigated plots. These reductions could be correlated with decreases in rates of photosynthetic CO₂ assimilation determined by independent groups of researchers working on the Liphook site.     

Host selection behaviour of the banded pine weevil,Pissodes castaneus (Coleoptera: Curculionidae)

1. Pissodes castaneus represents an emerging pest species for Pinus spp. production in Latin America. This species attacks all the cultivated pine species in Patagonia Argentina causing wood damage and tree death. The objectives of this work were to describe the host preference behaviour of P. castaneus and the influence of wood damage by conspecifics on its host selection.
2. In two-choice bioassays, P. castaneus showed a feeding preference for Pinus contorta over P. ponderosa. However, percent weight gain when feeding on either species was similar.
3. In other bioassays, P. castaneus spent more time in areas with twigs on which other conspecifics had recently fed, although they were able to successfully feed on twigs without previous damage.
4. These results show that while P. castaneus can successfully colonize different pine species, P. contorta may be more susceptible to attack than P. ponderosa. Silvicultural management should be prioritized considering the weevil's preference for attacking damaged hosts.

     

Ants protect conifer seedlings from feeding damage by the pine weevil Hylobius abietis

• 1 Ants that protect food resources on plants may prey on (or deter) herbivores and thereby reduce damage. Red wood ants (of the Formica rufa group) are dominant ants in boreal forests of Eurasia and affect the local abundance of several herbivorous species.
• 2 The pine weevil Hylobius abietis (L.) is a herbivore that causes severe damage by feeding on the bark of coniferous seedlings within areas of forest regeneration.
• 3 We investigated whether ants can protect conifer seedlings from pine weevil feeding. In a manipulative experiment, ants were attracted to sugar baits attached to spruce seedlings and the damage caused by pine weevils was compared with control seedlings without ant‐baits.
• 4 The feeding‐scar area was approximately one‐third lower on the seedlings with ant‐baits compared with the controls. Besides red wood ants, Myrmica ants were also attracted in high numbers to the ant baits and the relative effects of these species are discussed.
• 5 The results obtained in the present study support the trophic cascade hypothesis (i.e. damage to herbivores is suppressed in the presence of predators). The decreased pine weevil feeding on the baited seedlings was probably a result of nonconsumptive interactions [i.e. the presence of (or harassment by) ants distracting pine weevils from feeding].
• 6 Understanding the role of ants may have important implications for future strategies aiming to control pine weevil damage. For example, maintaining suitable conditions for ants after harvesting stands may be an environmentally friendly but currently unexploited method of for decreasing weevil damage.

     

Pine pest aphids of the genus Eulachnus (Hemiptera: Aphididae: Lachninae): how far can their range extend?

相似文献