994 resultados para Scots Pine
Resumo:
Changes in the polyamine content were analyzed in different embryo developmental stages and tissues during seed development in the conifer Araucaria angustifolia (Bert.) O. Ktze. Free polyamine contents varied according to the tissue and stage of embryo development, the highest levels occurring in the embryonic axis at the early stages, when putrescine and spermidine were most abundant. The levels of spermidine were higher from the stage where cotyledons arise, whereas putrescine decreases. The putrescine/spermine+spermidine ratio was higher during the initial phases of seed development, corresponding to cell multiplication and elongation, with a decrease in the final stages, corresponding to stabilization of the dry matter content.
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This investigation aims to gain a better understanding of the glacial history of the Pine Point Mining district, Northwest Territories, by examining the sedimentological properties of the glacial sediments including, geochemical analysis, heavy mineral concentrate analysis, clast macro-‐fabrics, pebble lithologies, and micromorphological investigation. Four till units were identified, and three were associated with identified erosional bedrock features and streamlined landforms in the area, indicating a minimum of three ice flow directions. Sedimentological properties suggest that these units were all Type-B tectomict/mélange till, emplaced as part of a soft subglacial deformable bed. The lack of ice-‐marginal advance and retreat sequences within the studied till, suggests the Middle Wisconsinan Laurentide Ice margin was likely north and west of the Pine Point area, as opposed to along the margin of the Canadian Shield and Western Sedimentary Basin where it has been suggested to have existed.
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Voucher from the Engineer Department of Port Dalhousie and Thorold Railway Extension to John Gilleland for supplies. This is accompanied by a note about pine lumber and fencing, Apr. and May, 1857.
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Salvage logging is a common practice carried out in burned forests worldwide, and intended to mitigate the economic losses caused by wildfires. Logging implies an additional disturbance occurring shortly after fire, although its ecological effects can be somewhat mitigated by leaving wood debris on site. The composition of the bird community and its capacity to provide ecosystem services such as seed dispersal of fleshy-fruited plants have been shown to be affected by postfire logging. We assessed the effects of the habitat structure resulting from different postfire management practices on the bird community, in three burned pine forests in Catalonia (western Mediterranean). For this purpose, we focused on the group of species that is responsible for seed dispersal, a process which takes place primarily during the winter in the Mediterranean basin. In addition, we assessed microhabitat selection by seed disperser birds in such environments in relation to management practices. Our results showed a significant, positive relationship between the density of wood debris piles and the abundance of seed disperser birds. Furthermore, such piles were the preferred microhabitat of these species. This reveals an important effect of forest management on seed disperser birds, which is likely to affect the dynamics of bird-dependent seed dispersal. Thus, building wood debris piles can be a useful practice for the conservation of both the species and their ecosystem services, while also being compatible with timber harvesting
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There is a strong desire to exploit transcriptomics data from model species for the genetic improvement of non-model crops. Here, we use gene expression profiles from the commercial model Pinus taeda to identify candidate genes implicated in juvenile-mature wood transition in the non-model relative, P. sylvestris. Re-analysis of 'public domain' SAGE data from xylem tissues of P. taeda revealed 283 mature-abundant and 396 juvenile-abundant tags (P < 0.01), of which 70 and 137, respectively matched to genes with known function. Based on sequence similarity, we then isolated 16 putative homologues of genes that in P. taeda exhibited widest divergence in expression between juvenile and mature samples. Candidate expression levels in P. sylvestris were almost invariably differential between juvenile and mature woody tissue samples among two cohorts of five trees collected from the same seed source and selected for genetic uniformity by genetic distance analysis. However, the direction of differential expression was not always consistent with that described in the original P. taeda SAGE data. Correlation was observed between gene expression and juvenile-mature wood anatomical characteristics by OPLS analysis. Four candidates (alpha-tubulin, porin MIP1, lipid transfer protein and aquaporin like protein) apparently had greatest influence on the wood traits measured. Speculative function of these genes in relation to juvenile-mature wood transition is briefly explored. Thus, we demonstrate the feasibility of exploiting SAGE data from a model species to identify consistently differentially expressed candidates in a related non-model species.
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Larvae of the pine beauty moth Panolis flammae (Denis & Schiffermuller) were reared in sleeve cages on five different seed origins (provenances) of pole stage Pinus contorta in the field in each of four years from 1985 to 1988. Survival varied significantly between the years. In those years when survival was high, significant differences between tree provenance were not found. However, between provenance significant differences were found in larval weight and stage of development. In the years when survival was low, the results seen in good years were reversed. Significant differences attributable to provenance were found but these were not reflected in significant differences between larval weight or development. In addition, there was a significant correlation between the proportion surviving and larval weight, which was not the case in those years where larval survival was high. The results are discussed in light of the pest status of P, flammea in Britain and in view of current silvicultural policies. The use of trees resistant to insect attack as part of an integrated pest management programme is highlighted and the need to coordinate laboratory and field studies so as to control for environmental variation discussed.
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Pine beauty moth (Panolis flammea D&S, Lepidoptera: Noctuidae) were reared individually from egg hatch to pupation on one of three host plants, Pinus sylvestris (native host plant), Pinus contorta (Central Interior seed origin - good quality introduced host) and P. contorta (Alaskan seed origin - poor quality introduced host). After emerging from the pupae the adult moths were confined to a Skeena River seed origin of P. contorta. Female pupal weight and adult life span were significantly higher on P. sylvestris than on the two lodgepole pine seed origins. Development time was, however, not significantly different between treatments, but larval mean relative growth rate was found to be negatively correlated with birth weight and positively correlated with pupal weight. The time to emerge from the pupa was also not significantly different between treatments. However, there were marked differences between the genders. Male moths lost a significantly greater proportion of their weight over the pupal stage but lived significantly longer as adults than the females. Female moths emerged from the pupal stage significantly sooner than male moths. There was no apparent advantage of lai-ge birth size when looked at in terms of subsequent performance. These results are discussed in light of current life history theory.
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Entomopathogenic nematodes (EPN) frequently kill their host within 1–2 days, and interest in EPN focuses mainly on their lethality. However, insects may take longer to die, or may fail to die despite being infected, but little is known about the effects of EPN infection on insects, other than death. Here we investigate both lethal and sub-lethal effects of infection by two EPN species, Steinernema carpocapsae and Heterorhabditis downesi, on adults of the large pine weevil, Hylobius abietis. Following 12 h nematode–weevil contact in peat, S. carpocapsae killed a significantly higher proportion of weevils (87–93%) than H. downesi (43–57%) at all concentrations tested. Less than 10% of weevils were dead within 2 days, and weevils continued to die for up to 10 days after exposure (LT50 of 3 days or more). In a separate experiment, live weevils dissected 6 days after a 24 h exposure to nematodes on filter paper harbored encapsulated and dead nematodes, showing that weevils could defend themselves against infection. Some live weevils also harbored live nematodes 6 days after they had been removed from the nematode infested medium. Feeding by weevils was not affected by infection with, or exposure to, either species of EPN. We discuss these results in relation to the use of EPN in biological control against H. abietis.
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Background Pine bark is a rich source of phytochemical compounds including tannins, phenolic acids, anthocyanins, and fatty acids. These phytochemicals have potential to significantly impact on animal health and animal production. The goal of this work is to measure the effects of tannins in ground pine bark as a partial feed replacement on feed intake, dietary apparent digestibility, nitrogen balance, and mineral retention in meat goats. Results Eighteen Kiko cross goats (initial BW = 31.8 ± 1.49 kg) were randomly assigned to three treatment groups (n = 6). Dietary treatments were tested: control (0 % pine bark powder (PB) and 30 % wheat straw (WS)); 15 % PB and 15 % WS, and 30 % PB and 0 % WS. Although dry matter (DM) intake and digestibility were not affected (P > 0.10) by feeding PB, neutral detergent fiber (linear; P = 0.01), acid detergent fiber (linear; P = 0.001) and lignin digestibility (linear; P = 0.01) decreased, and crude protein (CP) digestibility tended to decrease (P = 0.09) as PB increased in the diet, apparent retention of Ca (P = 0.09), P (P = 0.03), Mg (P = 0.01), Mn (P = 0.01), Zn (P = 0.01) and Fe (P = 0.09) also increased linearly. Nitrogen intake and fecal N excretion were not affected (P > 0.05) by addition of PB in the diet, but N balance in the body was quadratically increased (P < 0.01) in the 15 % PB diet compared to other diets. This may be due to more rumen escape protein and less excreted N in the urine with the 15 % PB diet. The study showed that a moderate level of tannin-containing pine bark supplementation could improve gastrointestinal nitrogen balance with the aim of improving animal performance. Conclusion These results suggest that tannin-containing PB has negative impact on fiber, lignin, and protein digestibility, but positively impacted on N-balance.
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Sustainable methods are required to protect newly planted tree seedlings from insect herbivore attack. To this end, here Norway spruce (Picea abies (L.) Karst.) seeds were treated with 2.5 mM nicotinamide (NIC), 2.5 mM nicotinic acid (NIA), 3 mM jasmonic acid (JA) or 0.2 mM 5-azacytidine (5-Aza), and 6-month-old seedlings grown from these seeds were planted at a reforestation area in central Sweden. Attack by pine weevils (Hylobius abietis) was reduced by 50 per cent by NIC treatment, 62.5 per cent by JA treatment and 25 per cent by 5-Aza treatment, when compared with seedlings grown from untreated seeds. Watering 18-month-old spruce seedlings with 2 mM NIC or 2 mM NIA did reduce attack during the first season in the field by 40 and 53 per cent, respectively, compared with untreated plants. Girdling was also reduced by the different treatments. Analysis of conifer seedlings treated with 5-Aza points at a possible involvement of epigenetic mechanisms in this defensive capacity. This is supported by a reduced level of DNA methylation in the needles of young spruce seedlings grown in a greenhouse from NIC-treated seeds. Seed treatment for seedling defense potentiation is simple, inexpensive and also a new approach for forestry with many potential applications.
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More than 95% of the reforested area in Brazil is covered by exotic Eucalyptus and Pinus plantations. Native Scolytidae, mostly ambrosia beetles, appear to be rapidly adapting to these exotic trees, and reports of economic damage are becoming frequent. The objectives of our research were to survey, characterize and compare the Scolytidae fauna present in a P. taeda and an E. grandis stand in Telemaco Borba, Parana state, Brazil. Beetles were caught in ethanol baited ESALQ-84 vane traps in weekly collections from July 1995 until July 1997. In all, 87 species were trapped, 62 in the pine and 75 in the eucalypt stand. The most abundant beetle species in the pines were Hypothenemus eruditus, Xyleborinus gracilis, Cryptocarenus sp. and Xylosandrus retusus, while the most frequent were H. eruditus, Cryptocarenus sp., H. obscurus, Ambrosiodmus obliquus, and X. gracilis. In the eucalypt stand, H. eruditus, X. retusus, H. obscurus, X. ferrugineus and Microcorthylus minimus were the most abundant species, and H. eruditus, H. obscurus and M. minimus were the most frequently trapped. The majority of the species, regardless of the forest community, were most active between August (end of winter) and October (mid-spring). Significantly more H. eruditus, X. gracilis, Cryptocarenus sp., Corthylus obliquus, Hypothenemus bolivianus, A. obliquus, Sampsonius dampfi and Xyleborus affinis were trapped in the pine stand, while X. retusus, H. obscurus, X. ferrugineus, Xyleborinus linearicollis, Corthylus sp, and Corthylus convexicauda were caught in higher numbers in the eucalypt stand. Approximately 50% of the species trapped were found in both communities. Morisita's similarity index indicates the composition of the two communities is very similar, suggesting that most of the beetles are polyphagous. (C) 2001 Elsevier B.V. B.V. All rights reserved.