Journal articles: 'PINNs'

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D’Ambrosio, Andrea, Enrico Schiassi, Fabio Curti, and Roberto Furfaro. "Pontryagin Neural Networks with Functional Interpolation for Optimal Intercept Problems." Mathematics 9, no. 9 (April 28, 2021): 996. http://dx.doi.org/10.3390/math9090996.

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In this work, we introduce Pontryagin Neural Networks (PoNNs) and employ them to learn the optimal control actions for unconstrained and constrained optimal intercept problems. PoNNs represent a particular family of Physics-Informed Neural Networks (PINNs) specifically designed for tackling optimal control problems via the Pontryagin Minimum Principle (PMP) application (e.g., indirect method). The PMP provides first-order necessary optimality conditions, which result in a Two-Point Boundary Value Problem (TPBVP). More precisely, PoNNs learn the optimal control actions from the unknown solutions of the arising TPBVP, modeling them with Neural Networks (NNs). The characteristic feature of PoNNs is the use of PINNs combined with a functional interpolation technique, named the Theory of Functional Connections (TFC), which forms the so-called PINN-TFC based frameworks. According to these frameworks, the unknown solutions are modeled via the TFC’s constrained expressions using NNs as free functions. The results show that PoNNs can be successfully applied to learn optimal controls for the class of optimal intercept problems considered in this paper.

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Duñabeitia, Miren K., Susana Hormilla, Isabel Salcedo, and Jose I. Peña. "Ectomycorrhizae synthesized between Pinus radiata and eight fungi associated with Pinns spp." Mycologia 88, no. 6 (November 1996): 897–908. http://dx.doi.org/10.1080/00275514.1996.12026730.

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Schiassi, Enrico, Mario De Florio, Andrea D’Ambrosio, Daniele Mortari, and Roberto Furfaro. "Physics-Informed Neural Networks and Functional Interpolation for Data-Driven Parameters Discovery of Epidemiological Compartmental Models." Mathematics 9, no. 17 (August 27, 2021): 2069. http://dx.doi.org/10.3390/math9172069.

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In this work, we apply a novel and accurate Physics-Informed Neural Network Theory of Functional Connections (PINN-TFC) based framework, called Extreme Theory of Functional Connections (X-TFC), for data-physics-driven parameters’ discovery of problems modeled via Ordinary Differential Equations (ODEs). The proposed method merges the standard PINNs with a functional interpolation technique named Theory of Functional Connections (TFC). In particular, this work focuses on the capability of X-TFC in solving inverse problems to estimate the parameters governing the epidemiological compartmental models via a deterministic approach. The epidemiological compartmental models treated in this work are Susceptible-Infectious-Recovered (SIR), Susceptible-Exposed-Infectious-Recovered (SEIR), and Susceptible-Exposed-Infectious-Recovered-Susceptible (SEIRS). The results show the low computational times, the high accuracy, and effectiveness of the X-TFC method in performing data-driven parameters’ discovery systems modeled via parametric ODEs using unperturbed and perturbed data.

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Wang, Tianyi, and Xuebin Chi. "The PINNs method discovery to the solution of coupled Wave- Klein-Gordon equations." Journal of Physics: Conference Series 1754, no. 1 (February 1, 2021): 012228. http://dx.doi.org/10.1088/1742-6596/1754/1/012228.

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Song, Chao, Tariq Alkhalifah, and Umair Bin Waheed. "Solving the frequency-domain acoustic VTI wave equation using physics-informed neural networks." Geophysical Journal International 225, no. 2 (January 11, 2021): 846–59. http://dx.doi.org/10.1093/gji/ggab010.

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SUMMARY Frequency-domain wavefield solutions corresponding to the anisotropic acoustic wave equation can be used to describe the anisotropic nature of the Earth. To solve a frequency-domain wave equation, we often need to invert the impedance matrix. This results in a dramatic increase in computational cost as the model size increases. It is even a bigger challenge for anisotropic media, where the impedance matrix is far more complex. In addition, the conventional finite-difference method produces numerical dispersion artefacts in solving acoustic wave equations for anisotropic media. To address these issues, we use the emerging paradigm of physics-informed neural networks (PINNs) to obtain wavefield solutions for an acoustic wave equation for transversely isotropic (TI) media with a vertical axis of symmetry (VTI). PINNs utilize the concept of automatic differentiation to calculate their partial derivatives, which are free of numerical dispersion artefacts. Thus, we use the wave equation as a loss function to train a neural network to provide functional solutions to the acoustic VTI form of the wave equation. Instead of predicting the pressure wavefields directly, we solve for the scattered pressure wavefields to avoid dealing with the point-source singularity. We use the spatial coordinates as input data to the network, which outputs the real and imaginary parts of the scattered wavefields and auxiliary function. After training a deep neural network, we can evaluate the wavefield at any point in space almost instantly using this trained neural network without calculating the impedance matrix inverse. We demonstrate these features on a simple 2-D anomaly model and a 2-D layered model. Additional tests on a modified 3-D Overthrust model and a 2-D model with irregular topography further validate the effectiveness of the proposed method.

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Yang, Liu, Xuhui Meng, and George Em Karniadakis. "B-PINNs: Bayesian physics-informed neural networks for forward and inverse PDE problems with noisy data." Journal of Computational Physics 425 (January 2021): 109913. http://dx.doi.org/10.1016/j.jcp.2020.109913.

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Różycki, H., and E. Strzelczyk. "Free amino acids production by actinomycetes, isolated from soil, rhizosphere, and mycorrhizosphere of pine (Pinns sylvestris L.)." Zentralblatt für Mikrobiologie 141, no. 6 (1986): 423–29. http://dx.doi.org/10.1016/s0232-4393(86)80032-4.

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Różycki, H., and E. Strzelczyk. "Synthesis of free amino acids by bacteria isolated from soil, rhizosphere, and mycorrhizosphere of pine (Pinns sylvestris L.)." Zentralblatt für Mikrobiologie 140, no. 1 (1985): 41–53. http://dx.doi.org/10.1016/s0232-4393(85)80025-1.

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Ots, Katri, and Jtiri Rauk. "Influence of Climatic Factors on Annual Rings of Conifers." Zeitschrift für Naturforschung C 54, no. 7-8 (August 1, 1999): 526–33. http://dx.doi.org/10.1515/znc-1999-7-811.

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Abstract Relationships of the width of annual rings of 75-85-year old Pinns sylvestris L. and Picea abies (L.) Karst, with average monthly temperature, amount of precipitation and a complex climatic indicator developed on their basis was studied against the background of pollution load in the zone influenced by a cement plant and in a control area. Multiple regression analysis (equations with two and three independent variables) showed a significant correlation between precipitation and temperatures with increment, especially for pine: however, the prediction capability of the models is modest, describing usually 35-40% of the variation in radial increment. The calculations suggest that precipitation amounts are more important and temperature parameters less important and can be replaced by one another in the models. A direct correlation with the pollution load can be observed: at probability (P) near zero the coefficients for precipitation were the highest (0.45-0.51) in the area strongly affected by the cement plant and the lowest (0.31 -0.35) in the weakly affected and control areas. In case of spruce shortage of air humidity during summer months was important for increment, especially so in the heavily polluted area.

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Joyner, Karen L., Xiao-Ru Wang, J. Spencer Johnston, H. James Price, and Claire G. Williams. "DNA content for Asian pines parallels New World relatives." Canadian Journal of Botany 79, no. 2 (February 1, 2001): 192–96. http://dx.doi.org/10.1139/b00-151.

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This hypothesis is based on an observed correlation between DNA content and thermal regime for fish, zooplankton, salamanders, and some flowering plants. The Asian pine results provided no support for the latitudinal hypothesis; Asian tropical pine species did not have smaller genomes than their temperate or boreal relatives. DNA content of haploid megagametophyte tissue varied from 21.85 pg/C for hard pine Pinus densiflora Sieb. & Zucc. to 29.59 pg/C for soft pine Pinus bungeana Zucc. Pinus merkusii Jung. & De Vriese (29.63 pg/C) was the exceptional hard pine, with a genome size larger than many soft pines. The mean DNA content of Asian soft pines exceeded Asian hard pines (Δ 3.22 pg/C), a parallel to the previously reported trends for New World pines. No continental effect was detected. Based on 46 pines species sampled in centers of species diversity in Asian and the New World, soft pines had mean DNA content which exceeded hard pines by 4.97 pg/C.Key words: gymnosperms, conifers, laser flow cytometry, megagametophytes, C values, phylogeny.

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Akumu, Clement, Raphael Smith, and Solomon Haile. "Mapping and Monitoring the Canopy Cover and Greenness of Southern Yellow Pines (Loblolly, Shortleaf, and Virginia Pines) in Central-Eastern Tennessee Using Multi-Temporal Landsat Satellite Data." Forests 12, no. 4 (April 16, 2021): 499. http://dx.doi.org/10.3390/f12040499.

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Southern yellow pines such as loblolly, Virginia and shortleaf pines constitute forest products and contribute significantly to the economy of the United States (U.S.). However, little is understood about the temporal change in canopy cover and greenness of southern yellow pines, especially in Tennessee where they are used for timber and pulpwood. This study aims to map and monitor the canopy cover and greenness of southern yellow pines i.e., loblolly (Pinus taeda), shortleaf (Pinus echinata), and Virginia (Pinus Virginiana) pines in the years 1988, 1999 and 2016 in central-eastern Tennessee. Landsat time-series satellite data acquired in December 1988, November 1999 and February 2016 were used to map and monitor the canopy cover and greenness of loblolly, shortleaf and Virginia pines. The classification and mapping of the canopy cover of southern yellow pines were performed using a machine-learning random forest classification algorithm. Normalized Difference Vegetation Index (NDVI) was used to monitor the temporal variation in canopy greenness. In total, the canopy cover of southern yellow pines decreased by about 35% between December 1988 and February 2016. This information could be used by foresters and forest managers to support forest inventory and management.

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Echt, C. S., G. G. Vendramin, C. D. Nelson, and P. Marquardt. "Microsatellite DNA as shared genetic markers among conifer species." Canadian Journal of Forest Research 29, no. 3 (March 1, 1999): 365–71. http://dx.doi.org/10.1139/x99-009.

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Polymerase chain reaction (PCR) primer pairs for 21 simple sequence repeat (SSR) loci in Pinus strobus L. and 6 in Pinus radiata D. Don. were evaluated to determine whether SSR marker amplification could be achieved in 10 other conifer species. Eighty percent of SSR primer pairs for (AC)n loci that were polymorphic in P. strobus also amplified SSR loci in two other soft pines of the subgenus Strobus but not in seven hard pines of the subgenus Pinus, nor in Picea glauca (Moench) Voss or Pseudotsuga menziesii (Mirb.) Franco. The six P. strobus SSR primer pairs that did amplify loci from conifers other than soft pines were those that were specific to loci monomorphic within P. strobus. These six loci were also monomorphic within seven other species tested, but four of the loci were polymorphic among species. A comparison of allelic variation among the three soft pine species found only 25 shared alleles among a total of 122 alleles at eight loci. Primer pairs for dinucleotide SSR loci that were polymorphic in Pinus radiata also specifically amplified loci from various other hard pines but not from the soft pines or from the other conifers tested.

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Molina-Freaner, Francisco, Patricia Delgado, Daniel Piñero, Nidia Perez-Nasser, and Elena Alvarez-Buylla. "Do rare pines need different conservation strategies? Evidence from three Mexican species." Canadian Journal of Botany 79, no. 2 (February 1, 2001): 131–38. http://dx.doi.org/10.1139/b00-155.

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Mexico is a major center of diversity for the genus Pinus as it has the greatest number of species in the world. Many species are now restricted to Mexico, and some are represented by very small populations and are in danger of extinction. In this study we examined allozyme variation in three rare species of Mexican pines: Pinus pinceana Gord., Pinus lagunae M.F. Passini, and Pinus muricata D. Don, with the objective of providing conservation guidelines. The three species had relatively high levels of genetic variation with mean expected heterozygosities of 0.373, 0.386, and 0.346 for P. pinceana, P. lagunae, and P. muricata, respectively. We found marked differentiation among populations and significant inbreeding within populations of the three species. These values are larger than the range reported for most conifers and suggest that conservation strategies of these rare pines require focusing on the viability of several populations. Given that our knowledge about the demographic status of the three species is scarce, we propose a mixed strategy of conservation. For P. lagunae, we propose an in situ strategy, whereas for P. pinceana and P. muricata we propose an ex situ strategy of conservation until permanent protection can be provided for several of their populations.Key words: genetic structure, conservation, rare pines, Pinus pinceana, Pinus lagunae, Pinus muricata.

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Hunt, D. W. A., G. Lintereur, S. M. Salom, and K. F. Raffa. "PERFORMANCE AND PREFERENCE OF HYLOBIUS RADIUS BUCHANAN, AND H. PALES (HERBST) (COLEOPTERA: CURCULIONIDAE) ON VARIOUS PINUS SPECIES." Canadian Entomologist 125, no. 6 (December 1993): 1003–10. http://dx.doi.org/10.4039/ent1251003-6.

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AbstractThe weevils Hylobius radicis Buchanan and Hylobius pales (Herbst) survived to adulthood more frequently, developed more rapidly, and weighed more as adults when reared on diet containing ground phloem from Scots pine, Pinus sylvestris L., or red pine, Pinus resinosa Aiton, than from jack pine, Pinus banksiana Lamb., or eastern white pine, Pinus strobus L. In feeding tests, both weevils preferred Scots pine, although jack pine was preferred over red and white pine. When reared on diets containing phloem from red pines which had received various amounts of nitrogenous fertilizer, H. radicis and H. pales performed significantly better at elevated concentrations of nitrogen. Hylobius radicis adults exhibited a feeding preference for twigs from red pines containing elevated nitrogen concentrations.

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Hunt, Ellis V., and J. David Lenhart. "Fusiform Rust Trends in East Texas." Southern Journal of Applied Forestry 10, no. 4 (November 1, 1986): 215–16. http://dx.doi.org/10.1093/sjaf/10.4.215.

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Abstract Four surveys of pine plantations in East Texas between 1969 and 1984 indicate that fusiform rust (Cronartium quercuum (Berk.) Miyabe ex Shirai f. sp. fusiforme) infection rates are increasing on slash pine (Pinus elliottii Engelm. var. elliottii) and either decreasing or about constant on loblolly pine (Pinus taeda L.). Currently, stem infections occur on about 1 in 2 slash pines and 1 in 14 loblolly pines. South. J. Appl. For. 10:215-216, Nov. 1986.

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Leege, Lissa M., and Peter G. Murphy. "Ecological effects of the non-native Pinus nigra on sand dune communities." Canadian Journal of Botany 79, no. 4 (April 1, 2001): 429–37. http://dx.doi.org/10.1139/b01-015.

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Owing to their successional nature, sand dunes provide an opportunity to examine the effects of non-native species introduced into multiple habitats. We investigated the biotic and abiotic effects of non-native Pinus nigra in four habitats on the dunes of the eastern shore of Lake Michigan. The 26 000 pines were planted in foredunes, forest edges, wetpannes, and inland blowouts as a stabilization measure in 19561972, and in 1995 the surviving trees ranged in stand density from 2741176 trees per hectare. Pinus nigra stands were associated with reduced cover of dune vegetation except in forest edges, and with depressed species richness only in wetpanne sites. Higher densities of woody stems occurred in P. nigra stands at the edge of native forest than in sites lacking P. nigra, suggesting that pines accelerate succession to a woody community. Pinus nigra stands were associated with lower light levels than native stands of comparable or greater stand densities (Pinus banksiana in wetpannes and Populus deltoides in foredunes). In addition, P. nigra sites were drier than P. banksiana sites in wetpannes. The non-native pines may have modified the four dune habitats and appear to be functionally different from stands of native trees.Key words: functional equivalency, non-native species, Pinus nigra, plant invasion, sand dunes.

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Espinoza Pelcastre, Cristhian, Sergio Hernández-León, David S. Gernandt, Oscar Arce-Cervantes, Rodrigo Rodríguez-Laguna, and José González-Ávalos. "Clave de identificación taxonómica con caracteres anatómicos foliares para especies de Pinus L. en Hidalgo." Revista Mexicana de Ciencias Forestales 9, no. 47 (May 11, 2018): 028–49. http://dx.doi.org/10.29298/rmcf.v9i47.167.

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En el estado de Hidalgo se distribuyen, naturalmente, 12 especies de pinos, de las cuales, Pinus pinceana y P. greggii están clasificados en categorías de riesgo. En este contexto es necesario generar información para la identificación taxonómica de Pinus, únicamente con base en caracteres anatómicos de acículas en individuos jóvenes que carecen de estróbilos femeninos. El objetivo del presente estudio fue establecer una clave dicotómica para la identificación de pinos de Hidalgo, a partir de su anatomía foliar. Se recolectaron ejemplares en diversas localidades, se obtuvieron cortes transversales de las acículas, con ellos se codificó una matriz de caracteres, la cual fue sometida a un análisis de similitud UPGMA; y se elaboró una clave taxonómica. Se logran diferenciar 10 de los 12 taxones, que incluyen a Pinus greggii, especie bajo categoría de riesgo. Pinus cembroides se diferencia de P. pinceana, solo cuando la forma de la acícula, en corte transversal, es semicircular. Los canales resiníferos externos se observaron solamente en individuos del subgénero Strobus; y los septales en P. oocarpa. El número de canales resiníferos es utilizado de manera complementaria para identificar, debido a su alta variación. El análisis UPGMA resultó en dos agrupaciones principales, en la primera se recuperaron dos subgrupos correspondientes a las especies del subgénero Strobus y del subgénero Pinus; en la segunda pertenecen al subgénero Pinus. Se concluye que la clave es robusta para la identificación de especies de pinos a escala local, exclusivamente mediante caracteres anatómicos foliares.

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Rappaport, Nancy Gillette, John D. Stein, Adolfo Arturo del Rio Mora, Gary DeBarr, Peter de Groot, and Sylvia Mori. "RESPONSES OF CONOPHTHORUS SPP. (COLEOPTERA: SCOLYTIDAE) TO BEHAVIORAL CHEMICALS IN FIELD TRIALS: A TRANSCONTINENTAL PERSPECTIVE." Canadian Entomologist 132, no. 6 (December 2000): 925–37. http://dx.doi.org/10.4039/ent132925-6.

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AbstractWe tested six behavioral chemicals, pityol, conophthorin, 4-allylanisole, verbenone, 2-hexenol, and α-pinene, in a series of field trials directed at six combinations of Conophthorus Hopkins – Pinus L. spp. (Pinaceae) in sites distributed across North America. Beetle – host tree combinations included Conophthorus ponderosae Hopkins on Pinus ponderosa Laws., C. ponderosae on Pinus monticola Dougl., Conophthorus conicolens Wood on Pinus pseudostrobus Lindl., Conophthorus teocotum Wood on Pinus teocote Schl. & Cham., Conophthorus coniperda (Schwarz) on Pinus strobus L., and Conophthorus resinosae Hopkins on Pinus resinosa 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 α-pinene appeared to parallel host phylogeny, inasmuch as beetles using Haploxylon pines as hosts utilized α-pinene as a synergist for the beetle-produced pityol, whereas beetles using Diploxylon pines as hosts did not. α-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 other beetle–host combinations, verbenone was neutral to slightly repellent and 4-allylanisole was either synergistic or neutral in pityol-baited traps. Promising synergists and interruptants/repellents were identified for implementation in pest-management regimes, including conophthorin as an interruptant for all species of Conophthorus tested, 4-allylanisole as an interruptant for C. ponderosae on P. ponderosa, α-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.

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Ning, Chen, Gregory Mueller, Louise Egerton-Warburton, Wenhua Xiang, and Wende Yan. "Host Phylogenetic Relatedness and Soil Nutrients Shape Ectomycorrhizal Community Composition in Native and Exotic Pine Plantations." Forests 10, no. 3 (March 15, 2019): 263. http://dx.doi.org/10.3390/f10030263.

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Exotic non-native Pinus species have been widely planted or become naturalized in many parts of the world. Pines rely on ectomycorrhizal (ECM) fungi mutualisms to overcome barriers to establishment, yet the degree to which host specificity and edaphic preferences influence ECM community composition remains poorly understood. In this study, we used high-throughput sequencing coupled with soil analyses to investigate the effect of host plant identity, spatial distance and edaphic factors on ECM community composition in young (30-year-old) native (Pinus massoniana Lamb.) and exotic (Pinus elliottii Engelm.) pine plantations in China. The ECM fungal communities comprised 43 species with the majority belonging to the Thelephoraceae and Russulaceae. Most species were found associated with both host trees while certain native ECM taxa (Suillus) showed host specificity to the native P. massoniana. ECM fungi that are known to occur exclusively with Pinus (e.g., Rhizopogon) were uncommon. We found no significant effect of host identity on ECM communities, i.e., phylogenetically related pines shared similar ECM fungal communities. Instead, ECM fungal community composition was strongly influenced by site-specific abiotic factors and dispersal. These findings reinforce the idea that taxonomic relatedness might be a factor promoting ECM colonization in exotic pines but that shifts in ECM communities may also be context-dependent.

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Bruederle, Leo P., Diana F. Tomback, Kathleen K. Kelly, and Renea C. Hardwick. "Population genetic structure in a bird-dispersed pine, Pinus albicaulis (Pinaceae)." Canadian Journal of Botany 76, no. 1 (January 1, 1998): 83–90. http://dx.doi.org/10.1139/b97-162.

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Whitebark pine (Pinus albicaulis) is the sole North American representative of Pinus subgenus Strobus section Strobi subsection Cembrae, a group of five species characterized by bird-dispersed seeds. Whereas population genetic structure has been described for several Eurasian Cembrae pines, the purpose of the present research was to quantify genetic diversity in whitebark pine and assess the distribution of genetic variation within and among populations interpreted within the context of this species' unique life history. Allozyme analyses were conducted on nine populations from the Greater Yellowstone Area. Genetic diversity, as measured by population means for percentage of loci polymorphic, number of alleles per locus, and expected heterozygosity was relatively low (i.e., 38.57, 1.66, 0.152) when compared with means reported for pines with wind-dispersed seeds. Genetic differentiation was also low (i.e., 0.025) relative to means reported for other gymnosperms including wind-dispersed pines. These populations are poorly differentiated, with the majority of all observed variation due to differences among individuals within populations. The data reported herein for whitebark pine populations are similar to those reported for other Cembrae pines and may reflect their recent evolutionary history, as well as life history, including documented bird dispersal of seeds.Key words: population genetic structure, plant evolutionary biology, bird dispersal, Pinus albicaulis, Pinaceae.

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Sánchez-González, Arturo. "Una visión actual de la diversidad y distribución de los pinos de México." Madera y Bosques 14, no. 1 (August 30, 2016): 107–20. http://dx.doi.org/10.21829/myb.2008.1411222.

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México es considerado un centro secundario de diversidad del género Pinus. Un análisis de la literatura más reciente indica que los pinos migraron hacia el actual territorio mexicano desde el hemisferio norte a través de corredores naturales e impulsados por los cambios climáticos del pasado. Los procesos de diversificación del género ocurrieron en las principales cadenas montañosas de México, que funcionaron como corredores biológicos o como islas biogeográficas que definieron el patrón de distribución general actual de los pinos en cinco grandes regiones. Recientemente se reconocen para México 46 especies, 3 subespecies y 22 variedades de pinos. El 55% de estos taxa son endémicos. Lo que nos convierte en la nación con mayor diversidad al contar con alrededor de 42 % de las especies del mundo. Los pinos mexicanos son uno de los recursos naturales más valiosos por su uso tradicional y comercial, por su importancia cultural y por los servicios ambientales que ofrecen. A pesar de ello la continua disminución de la cobertura de los bosques de pino y pino-encino, por causa de las actividades humanas y por los incendios forestales, es alarmante. Al menos 20 taxa de pinos mexicanos están en alguna categoría de riesgo y dos de ellos: Pinus maximartinezii y P. muri cata se encuentran en peligro de extinción. Los programas nacionales e internacionales para el uso sostenible y la conservación del género Pinus en México aún no son eficientes y suficientes.

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Sokołowska, Joanna, Hanna Fuchs, and Konrad Celiński. "New Insight into Taxonomy of European Mountain Pines, Pinus mugo Complex, Based on Complete Chloroplast Genomes Sequencing." Plants 10, no. 7 (June 29, 2021): 1331. http://dx.doi.org/10.3390/plants10071331.

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The Pinus mugo complex is a large group of closely related mountain pines, which are an important component of the ecosystems of the most important mountain ranges, such as the Alps, Carpathians and Pyrenees. The phylogenetic relationships between taxa in this complex have been under discussion for many years. Despite the use of many different approaches, they still need to be clarified and supplemented with new data, especially those obtained with high-throughput methods. Therefore, in this study, the complete sequences of the chloroplast genomes of the three most recognized members of the Pinus mugo complex, i.e., Pinus mugo, Pinus rotundata and Pinus uncinata, were sequenced and analyzed to gain new insight into their phylogenetic relationships. Comparative analysis of their complete chloroplast genome sequences revealed several mutational hotspots potentially useful for the genetic identification of taxa from the Pinus mugo complex. Phylogenetic inference based on sixteen complete chloroplast genomes of different coniferous representatives showed that pines from the Pinus mugo complex form one distinct monophyletic group. The results obtained in this study provide new and valuable omics data for further research within the European mountain pine complex. They also indicate which regions may be useful in the search for diagnostic DNA markers for the members of Pinus mugo complex and set the baseline in the conservation of genetic resources of its endangered taxa.

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Hooker, Jamie M., Brian P. Oswald, Jeremy P. Stovall, Yuhui Weng, Hans M. Williams, and Jason Grogan. "Third Year Survival, Growth, and Water Relations of West Gulf Coastal Plain Pines in East Texas." Forest Science 67, no. 3 (May 10, 2021): 347–55. http://dx.doi.org/10.1093/forsci/fxab005.

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Abstract West Gulf Coastal Plain provenance loblolly (Pinus taeda L.), longleaf (Pinus palustris Mill.), shortleaf (Pinus echinata Mill.), and slash pines (Pinus elliottii Engelm.) were planted in December 2015 on three east Texas sites to compare initial growth and survival. Three years after planting, survival ranged from 26.4% to 76.4%. Damage by Texas leafcutter ants (Atta texana) caused significant mortality on one site, and feral hog (Sus scrofa) herbivory and uprooting greatly affected survival at two other sites. Tree heights were greater in loblolly and slash pine than in shortleaf and longleaf pine, whereas diameters were greater in loblolly than in slash, shortleaf, and longleaf. Height and survival rates were greater in Shelby County and were lowest in Cherokee County. Midday leaf-level water potentials were most negative for shortleaf and loblolly pines and varied across the three sites. Tree heights were significantly but weakly (R = −0.23) correlated to leaf-level water potentials.

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Hata, Kunihiko, and Kazuyoshi Futai. "Variation in fungal endophyte populations in needles of the genus Pinus." Canadian Journal of Botany 74, no. 1 (January 1, 1996): 103–14. http://dx.doi.org/10.1139/b96-015.

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Endophytic fungi were isolated from the needles of 45 species and varieties of the genus Pinus planted in an arboretum, and the species composition of the endophytes were compared among the pines examined. In general, Leptostroma spp. and Cenangium ferruginosum Fr. ex Fr. were dominant in the middle segment of the needle, while on the basal segment, Phialocephala sp. was more frequently isolated than the other two taxa. Leptostroma spp. seemed to be excluded from the basal segment by Phialocephala sp. The endophytic mycobiota of pines belonging to the same taxonomic group was similar. The taxonomic affinities of the host pines strongly affected the colonization patterns of the endophytes, while the effects of factors such as sampling date, tree age, and location in the stand were much weaker. Keywords: endophytic fungi, Pinus, host preference.

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Dutra da Silva, Marcelo, and Marcos Paulo Rodrigues Lima. "EFEITO ESPACIAL DO PINUS NA PAISAGEM DO PARQUE NACIONAL DA LAGOA DO PEIXE, RS / SPATIAL EFFECT OF THE PINE ON THE LANDSCAPE OF THE PARQUE NACIONAL DA LAGOA DO PEIXE, RS." Geographia Meridionalis 2, no. 2 (December 29, 2016): 194. http://dx.doi.org/10.15210/gm.v2i2.9631.

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Na região costeira do Rio Grande do Sul os impactos causados pelo cultivo e dispersão do Pinus estão cada vez mais evidentes. Na região do Parque Nacional da Lagoa do Peixe extensas áreas de cultivo de Pinus alteraram a estrutura e a dinâmica da paisagem local. O entorno da Unidade está cercado e dentro as áreas de cultivo representam uma forte ameaça. O vento distribui as sementes, que vêm de toda parte, dificultando o manejo e a proteção do sistema. O efeito espacial do Pinus é intenso e as alterações mais severas podem ser observadas na margem da Lagoa do Peixe, junto ao campo de dunas, na faixa longitudinal de Pinus, paralela ao oceano. Nessa faixa o deslocamento natural das dunas parece ter sido modificado, acumulando areia, que aos poucos está superando o obstáculo e talvez seja uma questão de tempo até que alcancem um volume perigoso, capaz de invadir a lagoa. A exclusão do Pinus, aos poucos, vem sendo realizada, porém sem um plano estratégico de erradicação e sem considerar, também, a necessidade de restaurar a paisagem e reabilitar os processos naturais, perdidos na decomposição do desenho espacial original.Abstract:The impacts caused by the cultivation and dispersion of pines are increasingly evident in the coastal region of Rio Grande do Sul. Currently, the region of Lagoa do Peixe National Park has been affected by extensive pine cultivation areas that changed local landscape structure and dynamics. Not only pines surround the area but also remaining cultives inside the unit represent a threat. The wind distributes the seeds, which makes management and system protection a complicated matter. The pines spatial effect is intense and the most severe changes may be observed at the margin of the pond, next to the dunes, in the pines longitudinal range, parallel to the ocean. In this area, the dune natural movement appears to have been modified, settling the once drifting sand, which is slowly overcoming the obstacles. Maybe it is a matter of time until it reaches a dangerous volume, able to overrun the lagoon. The exclusion of pines gradually have been performed. However, it is urgent to develop a strategic plan of eradication and to consider the need to restore the landscape therefore rehabilitating natural processes lost in the decomposition of the original spatial design.Keywords: Cultivationof Pinus; CoastalLandscapes; Coast of Rio Grande do Sul.

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Hernández-Tecles, Enrique, Jorge De las Heras, Zaida Lorenzo, Miguel Navascués, and Ricardo Alia. "Identification of gene pools used in restoration and conservation by chloroplast microsatellite markers in Iberian pine species." Forest Systems 26, no. 2 (September 22, 2017): e05S. http://dx.doi.org/10.5424/fs/2017262-9030.

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Aim of study: To contribute to the characterization of the origin of material used in afforestation, restoration or conservation activities by using Cp-SSR markers.Area of study: We used information from the natural range of Iberian pines, from Spain.Materials and methods: We used Iberian pines as an example to undertook gene pool characterization based on a wide Iberian sample of 97 populations from five Pinus species (Pinus halepensis, Pinus pinaster, Pinus nigra, Pinus sylvestris and Pinus uncinata). Haplotypes from each analyzed tree (derived from nine chloroplast microsatellites markers in P. halepensis and six in the rest of the species) were obtained. Based on this information we subdivided each species in regions (considering both genetic structure and its application in afforestation, restoration and conservation programs) and tested the assignation of populations to the different groups based on the genetic distance among samples.Main results: The rate of successful identification of populations among the different species was very high (> 94 %) for P. nigra, P. sylvestris and P. uncinata, high (81 %) for P. pinaster, and low (< 65 %) for P. halepensis. Research highlights: Chloroplast DNA markers from extensive population datasets can be used to assign the origin of the forest reproductive material in some pine species.

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Jr., Elbert L. Little, and Aljos Farjon. "Pines: Drawings and Descriptions of the Genus Pinus." Systematic Botany 11, no. 4 (October 1986): 609. http://dx.doi.org/10.2307/2419039.

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Hunt, D. R., and A. Farjon. "Pines. Drawings and Descriptions of the Genus Pinus." Kew Bulletin 41, no. 2 (1986): 472. http://dx.doi.org/10.2307/4102964.

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Schmid, Rudolf, and A. Farjon. "Pines: Drawings and Descriptions of the Genus Pinus." Taxon 35, no. 3 (August 1986): 620. http://dx.doi.org/10.2307/1221946.

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ROMERO, A., M. LUNA, E. GARCÍA, and M. F. PASSINI. "Phenetic analysis of the Mexican midland pinyon pines, Pinus cembroides and Pinus johannis." Botanical Journal of the Linnean Society 133, no. 2 (June 2000): 181–94. http://dx.doi.org/10.1111/j.1095-8339.2000.tb01541.x.

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Da Ponte, Emmanuel, Sergi Costafreda-Aumedes, and Cristina Vega-Garcia. "Lessons Learned from Arson Wildfire Incidence in Reforestations and Natural Stands in Spain." Forests 10, no. 3 (March 5, 2019): 229. http://dx.doi.org/10.3390/f10030229.

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Wildfires are currently considered the major threat to forests in Mediterranean countries. It has been implied that a large percentage of arson-caused fires in Spain are connected with the extensive reforestation programs implemented between 1940 and 1970. However, no consistent studies have been conducted to study the relationships between arson-caused fires and stand origin. Therefore, the goal of this study was to analyze occurrences and model the influence of forest stand origin (artificial or not) on the development of wildfires in peninsular Spain. Twenty-one neural network models were trained to estimate fire incidence through fire type (surface or crown fire), burned area and total treed burned area, based on stand age (years), canopy cover (%), natural age class (from seedling to mature stages) and fuel type classification. Models were built for reforested stands and natural stands of Pinus pinaster Ait., the Mediterranean pines Pinus sylvestris L., Pinus nigra Arn., Pinus halepensis Mill. and Eucalyptus sp. L’Hér., or groups of these species, and the resulting models were compared. Reforested stands presented higher fire incidence than natural stands mainly for productive species like Pinus pinaster Ait. According to the fire type models, thickets had a large influence in the development of crown fires in reforested stands in a general model for all species, the model with the Mediterranean group of pines, and the Pinus pinaster Ait. model. Vertical continuity influenced crown fire propagation in natural Mediterranean pines and in Eucalyptus stands. Presence of shrubs, grasslands and wood slash was related to surface fires in models for both reforested and natural stands. The results suggested that stand origin was influential on fire incidence, at least with regard to fire type and commercial species in the northwestern region of Spain.

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Ross, Darrell W., Göran Birgersson, Karl E. Espelie, and C. Wayne Berisford. "Monoterpene emissions and cuticular lipids of loblolly and slash pines: potential bases for oviposition preference of the Nantucket pine tip moth." Canadian Journal of Botany 73, no. 1 (January 1, 1995): 21–25. http://dx.doi.org/10.1139/b95-003.

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Monoterpene emissions from intact 5- to 29-month-old loblolly and slash pine seedlings contained α-pinene, camphene, β-pinene, myrcene, sabinene, β-phellandrene, and limonene. α-Pinene made up > 50% of the volatiles from both species. β-Pinene was significantly more abundant in slash (35.6%) than in loblolly pine (15.3%), while myrcene was significantly more abundant in loblolly (10.9%) than in slash pine (3.4%). Cuticular lipids represented 0.11 and 0.06% of the dry weight biomass of shoots from loblolly and slash pines, respectively. Species differences in cuticular lipid composition were primarily in relative proportions of a group of unidentified compounds that appear to be saturated and unsaturated diols and (or) hydroxy alcohols with chain lengths of about 18 carbons. 10-Nonacosanol made up 16.2 and 14.1% of the total lipids recovered from loblolly and slash pines, respectively. The Nantucket pine tip moth, Rhyacionia frustrana (Comstock), may use these chemical differences to distinguish the susceptible loblolly pines from the resistant slash pines. Key words: Pinus taeda, Pinus elliottii, monoterpene emissions, cuticular lipids, Rhyacionia frustrana.

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Laflamme, G., and R. Blais. "Resistance of Pinus banksiana to the European race of Gremmeniella abietina." Phytoprotection 81, no. 2 (April 12, 2005): 49–55. http://dx.doi.org/10.7202/706199ar.

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In the early 1980s, more than 90% of mortality caused by Gremmeniella abietina, European race, was recorded in red pine (Pinus resinosa) plantations 200 km northwest of Montreal, Quebec, Canada. Surrounding jack pines (Pinus banksiana) did not appear to be affected. Consequently, foresters began to plant the affected areas with jack pine seedlings. In 1988, plots of 100 jack pines were established in three of the four selected plantations. As reference, red pine seedlings were planted in 1989 under similar conditions in the fourth plantation. Observations were carried out annually from 1989 to 1992. Mortality of red pine seedlings reached 70% in 1992 while all jack pines on the three experimental sites were free of the disease except for a tip blight, a distinctive feature allowing race identification in the field. The North American race symptoms were present at a very low incidence, but began to increase on site I in 1992. More than 10 years after planting, the jack pine trees still show resistance to the European race of G. abietina while all the red pines died.

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Catling, Paul M. "Identification and Status of the Introduced Black Pine, Pinus nigra, and Mugo Pine, Pinus mugo, in Ontario." Canadian Field-Naturalist 119, no. 2 (April 1, 2005): 224. http://dx.doi.org/10.22621/cfn.v119i2.110.

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Recent reference texts and other sources are contradictory regarding the spread of Pinus nigra and Pinus mugo from cultivation in Ontario. Both species have reproduced from plantings along roadsides but neither has been observed to occupy habitats in Ontario to the substantial reduction or exclusion of native species, or to substantially invade natural habitats. The more widely planted Black Pine has been recorded spreading at 24 localities throughout the eastern part of southern Ontario. Mugo Pine is reported spreading at 18 locations. Although evidently much less aggressive than Scots Pine (Pinus sylvestris), both Black and Mugo pines have a potential for negative impact on biodiversity in dry, rocky or sandy habitats, especially in connection with extensive plantings. A key for the identification of two-needle pines is included. Both P. nigra and P. mugo are highly variable and reported to hybridize extensively with other species.

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Widmer, Timothy L., and Stephen C. Dodge. "Infection of Select Pinaceae and Cupressaceae Seedlings to Phytophthora pinifolia." Plant Health Progress 20, no. 2 (January 1, 2019): 106–11. http://dx.doi.org/10.1094/php-02-19-0011-rs.

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Phytophthora pinifolia caused a devastating disease on Monterey pine (Pinus radiata) in Chile. This pathogen has not been reported in the United States, but there is concern should it arrive. There is little information regarding other hosts besides Monterey pine that may be susceptible to this pathogen. In the present study, other potential hosts within the Pinaceae and Cupressaceae were inoculated with zoospores of P. pinifolia and observed for symptoms and infection after 4 weeks. Similar to Monterey pine, knobcone (Pinus attenuata), bishop (P. muricata), and ponderosa (P. ponderosa) pines were highly infectious, whereas several important species such as loblolly pine (P. taeda) and Douglas fir (Pseudotsuga menziesii) showed no infection. P. pinifolia was also not recovered from slash (Pinus elliottii) and eastern white (P. strobus) pines. This study is important because it demonstrates other economically important tree hosts are at risk by P. pinifolia, should it enter the United States.

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Hummer, Kim E. "Horticultural Perspective: History of White Pine Blister Rust." HortScience 33, no. 3 (June 1998): 468d—468. http://dx.doi.org/10.21273/hortsci.33.3.468d.

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White pine blister rust, Cronartium ribicola J. C. Fischer, requires a pine (Pinus L.) and a Ribes L. as obligate alternate hosts. The center of diversity for this rust is east of the Ural Mountains, where the organism evolved with P. cembra L and R. nigrum var. sibericum L over several million years. Susceptible Pinus strobus L from North America was imported into England in 1710 and was transplanted throughout eastern Europe. In 1865, rust was first reported on these introduced pines in Eastonia. In the late 1800s, the white pine nursery industry continued to develop in Europe, but was declining in the United States. American foresters began importing white pines from Europe. Rust was found on cultivated currants in New York in 1906 and U.S. inspectors began examining for the disease. In 1910, infected white pines were imported from France into Vancouver, British Columbia; in 1911, infected pines were found in New Hampshire, Vermont, Massachusetts, Connecticut, Pennsylvania, Indiana, Ohio, Ontario, and Quebec. Additional rust-infected imported pines were found in nurseries in Wisconsin in 1913, and Minnesota in 1914. Rust spread to native pines in New York by 1915 and to Idaho by 1927. A summary of the blister rust control program, the recent spread of the disease, and the present state regulations will be presented.

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Golovchenko, L. A., N. G. Dishuk, S. V. Panteleev, and O. Yu Baranov. "New invasive specie of Mycosphaerella dearnessii in the composition of mycobiota of pine needles in the territory of Belarus." Proceedings of the National Academy of Sciences of Belarus, Biological Series 65, no. 1 (February 11, 2020): 98–105. http://dx.doi.org/10.29235/1029-8940-2020-65-1-98-105.

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Different pines species are heavily infected with fungal pathogens all over the world, some of them are alien species for European region. The potential invasion of alien species into forests, forest nurseries, urban greeneries causes great concern among Belarusian phytopathologists. In this regard, in recent years local scientists have been monitoring the phytosanitary state of natural and managed plantations to identify alien species. The aim of this investigation was to monitor the phytosanitary state of conifers in botanical and dendrological gardens, urban plantations and tree nurseries in the Republic of Belarus, and assessment of the incidence of alien pathogens of pines. There were used light microscopy and molecular genetic techniques. As a result of our research the brown spot needle blight fungus, Mycosphaerella dearnessii was for the first time noted in the region of the Republic of Belarus in a consignment of imported plants of pines Pinus mugo, Pinus nigra, Pinus ponderosa. The disease was revealed both on young and adult plants in botanical gardens and nurseries. In the forests, urban greeneries Mycosphaerella dearnessii is currently not identified. The fungus affects not only the old, but also young needles, strongly inhibiting the growth of trees. Based on the investigation results we suppose that this disease can be dangerous for pinetums in our country.

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Wu, J., K. V. Krutovskii, and S. H. Strauss. "Nuclear DNA diversity, population differentiation, and phylogenetic relationships in the California closed-cone pines based on RAPD and allozyme markers." Genome 42, no. 5 (October 1, 1999): 893–908. http://dx.doi.org/10.1139/g98-171.

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We studied nuclear gene diversity and population differentiation using 91-98 randomly amplified polymorphic DNA (RAPD) loci in the California closed-cone pines knobcone (Pinus attenuata Lemm.), bishop (P. muricata D. Don), and Monterey (P. radiata D. Don) pines. A total of 384 trees from 13 populations were analyzed for RAPDs and another sample of 242 trees from 12 of these 13 populations were analyzed at 32-36 allozyme loci, using a published data set. Twenty-eight of 30 (93%) comigrating RAPD fragments tested were found to be homologous by Southern hybridization in all three species. Using an enriched mitochondrial DNA (mtDNA) preparation and a chloroplast DNA (cpDNA) library as probes, two fragments of cpDNA origin, and one of mtDNA origin present among RAPD profiles were excluded from analysis of nuclear gene diversity. RAPD markers revealed moderately higher intrapopulation gene diversity and substantially higher total genetic diversity and population differentiation than did allozyme markers for each species. We performed a simulation study using allozyme data, which showed that the dominant and biallelic nature of RAPD markers could explain the differences observed in differentiation parameters, but not in gene diversity; RAPD phenotypes appear to represent more underlying gene diversity than do allozyme phenotypes. Results of joint phylogenetic analyses of both the RAPD and allozyme markers strongly supported a common ancestor for P. radiata and P. attenuata pines, and south-to-north migration histories for all three species.Key words: allozymes, dominance, gene diversity, Pinus attenuata, Pinus muricata, Pinus radiata, phylogeny, RAPDs.

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Mathiasen, R., C. Parks, J. Beatty, and S. Sesnie. "First Report of Psittacanthus angustifolius on Pines in Mexico and Guatemala." Plant Disease 84, no. 7 (July 2000): 808. http://dx.doi.org/10.1094/pdis.2000.84.7.808d.

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The mistletoe Psittacanthus angustifolius Kuijt (Loranthaceae) is a common parasite of pines in Honduras (2). In March we observed this mistletoe parasitizing a pine that Farjon and Styles (1) have classified as Pinus tecunumanii Eguiluz & J. P. Perry 4 km south of Jitotol, Chiapas, Mexico. The taxonomy of this host in Chiapas is controversial as Perry (3) classifies the Chiapas populations of this pine as Pinus oocarpa var. ochoterenai Martinez. We also observed P. angustifolius on P. oocarpa Schiede 4 km north of Jitotol. In addition, we found this mistletoe parasitizing Pinus maximinoi H. E. Moore approximately 15 km west of Ocosingo, Chiapas. In Guatemala, we observed P. angustifolius on P. oocarpa at several locations north and south of La Cumbre, Department Baja Verapaz. This mistletoe appears to be less common in Chiapas and Guatemala than it is in Honduras. We did not observe this mistletoe damaging its pine hosts in Mexico or Guatemala. This is the first report of P. angustifolius in both Mexico and Guatemala and the first report of this mistletoe on Pinus tecunumanii (or Pinus oocarpa var. ochoterenai). Specimens of P. angustifolius from the above pine hosts have been deposited at the Deaver Herbarium, Northern Arizona University, Flagstaff. References: (1) A. Farjon and B. Styles. Pinus (Pinaceae), Flora Neotropica, Monogr. 75, New York Botanical Garden, 1997. (2) Mathiasen et al. Plant Dis. 84:203, 2000. (3) J. Perry. The Pines of Mexico and Central America, Timber Press, Portland, Oregon, 1991

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Guerin-Laguette, Alexis, Claude Plassard, and Daniel Mousain. "Effects of experimental conditions on mycorrhizal relationships between Pinus sylvestris and Lactarius deliciosus and unprecedented fruit-body formation of the Saffron milk cap under controlled soilless conditions." Canadian Journal of Microbiology 46, no. 9 (September 1, 2000): 790–99. http://dx.doi.org/10.1139/w00-059.

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The mycorrhizal relationships between pines and two edible species of Lactarius sect. Dapetes were investigated by optimizing the experimental conditions of mycelial growth and of mycorrhizal colonization of pine seedlings. In vitro mycelial growth of Lactarius deliciosus and L. sanguifluus was improved on a buffered medium containing glucose, amino acids, and vitamins. Two methods of mycorrhization of pines with Lactarius deliciosus were tested. The mycorrhizal colonization was rapid and intense under non-aseptic conditions with a low nutrient supply and without exogenous glucose. A positive influence of mycorrhizal colonization on Pinus sylvestris growth was subsequently observed. Under axenic conditions and with a high nutrient supply, mycorrhization was stimulated at 10 g/L of exogenous glucose, irrespective of the phosphorus concentration. At high phosphorus level (1 mM) and 0.1, 1.0, or 10.0 g/L glucose, growth of Pinus sylvestris was reduced by inoculation. Stability and development of Pinus spp./Lactarius deliciosus symbioses were assayed in a climatic chamber using containers filled with a synthetic substrate. Over a 2-year culture period, the root systems of the pine seedlings were heavily colonized by Lactarius deliciosus. One year following inoculation, Lactarius deliciosus fruit-body primordia appeared associated with Pinus sylvestris seedlings. Six months later, two mature basidiomata were obtained. This is the first report of soilless fruit-body formation of this edible mushroom.Key words: ectomycorrhiza, inoculation, Lactarius deliciosus, Lactarius sanguifluus, Pinus, wild edible mushrooms.

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Trianoski, Rosilani, Jorge Luis Monteiro Matos, Setsuo Iwakiri, and José Guilherme Prata. "VARIAÇÃO LONGITUDINAL DA DENSIDADE BÁSICA DA MADEIRA DE ESPÉCIES DE PINUS TROPICAIS." FLORESTA 43, no. 3 (September 13, 2013): 503. http://dx.doi.org/10.5380/rf.v43i3.28252.

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O conhecimento das propriedades da madeira é de fundamental importância, pois está associado às diversas formas de transformação e utilização. Nesse contexto, este trabalho busca avaliar a variação longitudinal da densidade básica da madeira de espécies de pinus tropicais. Foram avaliadas sete espécies de pinus tropicais: Pinus caribaea var. bahamensis, Pinus caribaea var. caribaea, Pinus caribaea var. hondurensis, Pinus chiapensis, Pinus maximinoi, Pinus oocarpa e Pinus tecunumanii, além do Pinus taeda (referência), coletadas em plantios experimentais com 17 e 18 anos, localizados nas regiões de Itararé (SP) e Ventania (PR). Foram selecionadas cinco árvores por espécie, as quais foram seccionadas nas posições de 0%, 25%, 50%, 75% e 100% da altura comercial, para obtenção das amostras. A densidade básica foi determinada segundo a norma 461 da Comisión Panamericana de Normas Técnicas, ao passo que o percentual de lenho tardio foi quantificado pelo software Windendro, com base na análise de imagens digitalizadas dos discos das diferentes posições. Os resultados mostraram que todas as espécies apresentam densidade básica baixa (0,389 a 0,489 g/cm3), com coeficientes de variação entre 5,09% e 9,77%, podendo ser consideradas promissoras para plantios em escala comercial, aumentando a oferta de madeira para os diversos segmentos da indústria madeireira.AbstractLongitudinal variation of basic density of wood of tropical pine species. The wood properties knowledge has fundamental importance since it is associated to many processing and using ways. In this context, this paper aims to evaluate longitudinal variation of basic density of wood of tropical pines species. It evaluated seven species of tropical pines: Pinus caribaea var. bahamensis, Pinus caribaea var. caribaea, Pinus caribaea var. hondurensis, Pinus chiapensis, Pinus maximinoi, Pinus oocarpa, Pinus tecunumanii, beyond Pinus taeda (reference), collected in experimental plantations at 17 and 18 years of age, located in the regions of Itararé (SP) and Ventania (PR). Five trees were selected by species, which were sectioned at positions 0%, 25%, 50%, 75% and 100% of the commercial height for samples. Basic density was determined according to the standard 461 of Comisión Panamericana de Normas Técnicas, besides the percentage of latewood, quantified by Windendro software, based on analysis of scanned images of disks of different positions. The results revealed that all species presented low basic density (0.389 to 0.489 g/cm3) with coefficients of variation between 5.09% to 9.77%, and can be considered promising for commercial scale cultivation, in this way increasing the wood supply for different segments of timber industry.Keywords: Pinus spp.; wood properties; laterwood.

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MacFall, J. S., J. Iyer, S. Slack, and J. Berbee. "Mycorrhizal-phosphorus interaction on red pines (Pinus resinosa Ait.)." Agriculture, Ecosystems & Environment 28, no. 1-4 (February 1990): 321–24. http://dx.doi.org/10.1016/0167-8809(90)90058-l.

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Esch, Evan D., John R. Spence, and David W. Langor. "Saproxylic beetle (Coleoptera) diversity in subalpine whitebark pine and lodgepole pine (Pinaceae) trees killed by mountain pine beetles (Coleoptera: Curculionidae)." Canadian Entomologist 148, no. 5 (March 11, 2016): 556–68. http://dx.doi.org/10.4039/tce.2016.3.

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AbstractWhitebark pine,Pinus albicaulisEngelmann (Pinaceae), a foundational species of North American subalpine ecosystems, is endangered across its range and continued decline is inevitable. Little is known about the invertebrate fauna associated with this species which, if specific to whitebark pine, may also be threatened or endangered. We compared the composition of saproxylic beetle assemblages associated with whitebark pine and co-occurring lodgepole pine,Pinus contorta latifolia(Engelmann) Critchfield (Pinaceae), recently killed by mountain pine beetle (MPB),Dendroctonus ponderosaeHopkins (Coleoptera: Curculionidae), in subalpine forests in Alberta, Canada. Redundancy and rarefaction analyses revealed that beetle assemblage composition was influenced by snag class (i.e., time since death) but differed little among the two pine species within snag classes. However, a subset of the assemblage known to be associated with the MPB differed significantly in composition between the two pines. No common species were exclusively associated with whitebark pines; however, seven species were rarely collected only on whitebark pine. With the possible exception of these rare species, felling and burning infested whitebark pines to control the MPB will not likely endanger saproxylic beetles associated with this tree.

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Esch, Evan D., David W. Langor, and John R. Spence. "Gallery success, brood production, and condition of mountain pine beetles (Coleoptera: Curculionidae) reared in whitebark and lodgepole pine from Alberta, Canada." Canadian Journal of Forest Research 46, no. 4 (April 2016): 557–63. http://dx.doi.org/10.1139/cjfr-2015-0351.

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Breeding pairs of mountain pine beetle (Dendroctonus ponderosae Hopkins) were introduced into freshly cut bolts of whitebark pine (Pinus albicaulis Engelm.) and lodgepole pine (Pinus contorta var. latifolia Engelm. ex S. Watson) in the laboratory. Brood adults emerging from the bolts were collected and galleries were dissected to compare reproductive success, brood production, and adult condition between the two pines. Beetles were more likely to establish egg galleries that produced brood in lodgepole pine than in whitebark pine. Larval gallery density per centimetre of egg gallery was significantly higher in whitebark pine than in lodgepole pine; however, egg galleries also tended to be shorter in whitebark pine bolts, and consequently, brood adults emerging production per gallery did not differ between the two host species. Female body size, mass, and fat content of brood adults and survival from larva to adult did not differ between beetles reared in the two hosts. Though this no-choice assay did not simulate the sequence of events occurring during host selection, these results are consistent with other data suggesting that beetles could be less likely to attack whitebark pines in southwestern Alberta. Whitebark pines that are attacked will produce brood in similar numbers and condition as those from lodgepole pines.

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Rice, Adrianne V., Markus N. Thormann, and David W. Langor. "Mountain pine beetle associated blue-stain fungi cause lesions on jack pine, lodgepole pine, and lodgepole × jack pine hybrids in Alberta." Canadian Journal of Botany 85, no. 3 (March 2007): 307–15. http://dx.doi.org/10.1139/b07-014.

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Mountain pine beetles ( Dendroctonus ponderosae Hopkins; (MPB)) have spread into lodgepole × jack pine hybrid ( Pinus contorta Douglas × Pinus banksiana Lambert) forests in Alberta and are predicted to spread into jack pine forests. Their success in these forests is uncertain but will be influenced by multiple factors, including the ability of their associated blue-stain fungi to colonize the trees and the health of the encountered trees. Healthy and dwarf mistletoe infected pines at three sites across Alberta (one site per pine species) were inoculated with three isolates each of Grosmannia clavigera (Robinson-Jeffrey and Davidson) Zipfel, de Beer and Wingfield and Ophiostoma montium (Rumbold) von Arx. Both fungi grew and caused lesions on all hosts, suggesting that MPB will not be limited by a lack of fungal growth. Both fungi caused longer lesions in jack and hybrid pines than in lodgepole pines, indicating that susceptibility varies among hosts and is greater in the novel systems than in the co-evolved one. G. clavigera caused longer lesions than O. montium in hybrids and lodgepole pines, while the two species caused similar-sized lesions on jack pine. Intraspecific variation was high in G. clavigera, with one isolate producing much shorter lesions than the other two. Dwarf mistletoe infestation had little effect on infection lesion length.

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46

Hanberry, Brice B. "Transition from Fire-Dependent Open Forests: Alternative Ecosystem States in the Southeastern United States." Diversity 13, no. 9 (August 29, 2021): 411. http://dx.doi.org/10.3390/d13090411.

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Land use and fire exclusion have influenced ecosystems worldwide, resulting in alternative ecosystem states. Here, I provide two examples from the southeastern United States of fire-dependent open pine and pine-oak forest loss and examine dynamics of the replacement forests, given continued long-term declines in foundation longleaf (Pinus palustris) and shortleaf (Pinus echinata) pines and recent increases in commercial loblolly (Pinus taeda) and slash (Pinus elliottii var. elliottii) pines. Shortleaf pine-oak forest historically may have been dominant on about 32 to 38 million ha, a provisional estimate based on historical composition of 75% of all trees, and has decreased to about 2.5 million ha currently; shortleaf pine now is 3% of all trees in the northern province. Longleaf pine forest decreased from about 30 million ha, totaling 75% of all trees, to 1.3 million ha and 3% of all trees in contemporary forests of the southern province. The initial transition from open pine ecosystems to closed forests, primarily comprised of broadleaf species, was countered by conversion to loblolly and slash pine plantations. Loblolly pine now accounts for 37% of all trees. Loss of fire-dependent ecosystems and their foundation tree species affect associated biodiversity, or the species that succeed under fire disturbance.

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47

Zhao, Tao, and Bo Långström. "Performance ofTomicus yunnanensisandTomicus minor(Col., Scolytinae) onPinus yunnanensisandPinus armandiiin Yunnan, Southwestern China." Psyche: A Journal of Entomology 2012 (2012): 1–6. http://dx.doi.org/10.1155/2012/363767.

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Pine shoot beetles,Tomicus yunnanensisKirkendall and Faccoli andTomicus minorHartig (Col., Scolytinae), have been causing substantial mortality to Yunnan pine (Pinus yunnanensisFranch) in Yunnan, southwestern China, whereas only a few Armand pine (Pinus armandiiFranch) were attacked by the beetles. In order to evaluate the suitability ofP. armandiias host material for the twoTomicus, adults of bothTomicuswere caged on living branches and felled logs of the two pines during shoot feeding and trunk attack phase, respectively. More beetles survived on the living branches ofP. yunnanensisthan onP. armandii.Tomicus yunnanensisandT. minorproduced similar progeny in the logs of the two pines. The sex ratio and developmental period were not affected by host species, but the brood beetles emerging from Armand pine weighed less than those from Yunnan pine, suggesting thatP. armandiiare less suitable to be host ofT. yunnanensisandT. minor.

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48

Groeschl, DA, JE Johnson, and DW Smith. "Wildfire Effects on Forest Floor and Surface Soil in a Table Mountain Pine-Pitch Pine Forest." International Journal of Wildland Fire 3, no. 3 (1993): 149. http://dx.doi.org/10.1071/wf9930149.

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Wildfire plays a dominant role in creating die environmental and biological conditions necessary for the natural regeneration of mixed Pinus pungens Lamb. (Table Mountain pine)-Pinus rigida Mill. (pitch pine) forests. This study of forest floor and surface soil properties following a mid-July wildfire in these forests in the Shenandoah National Park revealed significant reductions in nutrient contents. Prolific regeneration of the pines occurred following the fire, with over 9,000 seedling/ha tallied in high severity areas, compared with less than 800 seedlings/ha in unburned areas. It is hypothesized that fire degrades site quality and sets back the site succession process so that the pines are better able to compete with invasive, xeric-site deciduous species like oaks and maples. Adjacent, unburned xeric-site oak forests dominate on more moist and fertile sites.

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Perdiguero, Pedro, María del Carmen Barbero, María Teresa Cervera, Carmen Collada, and Álvaro Soto. "Molecular response to water stress in two contrasting Mediterranean pines (Pinus pinaster and Pinus pinea)." Plant Physiology and Biochemistry 67 (June 2013): 199–208. http://dx.doi.org/10.1016/j.plaphy.2013.03.008.

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50

Cain, Michael D., and James P. Barnett. "Effects of Early Release on Natural Versus Container Loblolly Pines 12 Years After Field Establishment." Southern Journal of Applied Forestry 26, no. 4 (November 1, 2002): 173–80. http://dx.doi.org/10.1093/sjaf/26.4.173.

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Abstract Genetically improved, container loblolly pine (Pinus taeda L.) seedlings were compared to naturally established loblolly seedlings on a cutover pine site. Crop pines on 6 of 12 plots were released from woody and herbaceous competition within a 2 ft radius of each stem. On release plots, woody competition was controlled by hand-cutting for 5 consecutive yr and herbaceous competition was controlled with herbicides for 4 consecutive yr after pine establishment. Competition control increased 12 yr survival by 68 percentage points for natural pines and by 47 percentage points for planted pines. Twelve years after field establishment, mean-tree volume of planted pines was no different than that of naturally established pines. Nevertheless, volume gains of 150% to 200% were achieved within regeneration techniques as a result of release. South. J. Appl. For. 26(4):173–180.

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Journal articles on the topic 'PINNs'

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