Genetic load and heterozygosity in the Pinaceae

1986 ◽  
Vol 28 (6) ◽  
pp. 942-946 ◽  
Author(s):  
Thomas Mitchell-Olds ◽  
Raymond P. Guries
Keyword(s):  
Pinus Ponderosa ◽  
Picea Glauca ◽  
Pinus Contorta ◽  
Genetic Load ◽  
Large Numbers ◽  
Marker Loci ◽  
Isozyme Loci ◽  
Lethal Equivalents ◽  
Using Data ◽  
Deleterious Genes

Lethal genetic load might be caused by a few lethal genes or by large numbers of mildly deleterious polygenes. The extent of this lethal load can be quantified as the number of "lethal equivalents" in each individual. If there are large numbers of deleterious genes scattered throughout the genome then we might expect a correlation between the number of lethal equivalents and the level of heterozygosity at isozyme marker loci. Using data from 52 isozyme loci, we estimated this correlation on 68 individuals in four conifer species (Pinus ponderosa Laws., Pinus contorta Dougl., Picea glauca (Moench) Voss., and Pseudotsuga menziesii (Mirb.) Franco). No significant correlation was detected. We interpret this consistent result in four species as indicating that lethal equivalents do not represent large numbers of mildly deleterious polygenes in these forest trees.Key words: genetic load, lethal equivalent, Pinaceae, heterozygosity.

Tamarack (Pinaceae): previously unrecorded developmental host for pine engraver and southern pine engraver (Coleoptera: Scolytidae)

2002 ◽  
Vol 134 (3) ◽  
pp. 299-302 ◽  
Author(s):  
Kamal J.K. Gandhi ◽  
Steven J. Seybold
Keyword(s):  
North America ◽  
Pinus Ponderosa ◽  
Picea Glauca ◽  
Pinus Banksiana ◽  
Pinus Contorta ◽  
Ips Pini ◽  
Usda Forest Service ◽  
Pine Engraver ◽  
Adult Insect ◽  
Pinus Coulteri

The pine engraver, Ips pini (Say), is broadly distributed across North America (Lanier 1972; Wood 1982; Seybold et al. 1995) with a host range that includes most species of Pinus L., and in rare cases, species of Picea A. Dietrich (both Pinaceae), within its range (Swaine 1918; Bright 1976; Wood 1982; Furniss and Carolin 1992). Ips pini has been recorded from Pinus banksiana Lamb., Pinus resinosa Ait., and Pinus strobus L. (eastern North America), and from three of four subspecies of Pinus contorta Dougl. ex Loudon [P. c. contorta, P. c. latifolia (Engelm.) Critch., and P. c. murrayana (Balf.) Critch.], Pinus coulteri D. Don, Pinus jeffreyi Balf., Pinus ponderosa Dougl. ex P. and C. Laws., and Pinus flexilis James (western North America) (Furniss and Carolin 1992; Seybold et al. 1995). Hopping (1964) reported I. pini on Picea rubens Sarg., Picea glauca (Moench) Voss, and Picea engelmannii Parry ex Engelm. The adult insect is intermediate in length relative to most Ips spp., ranging from 3.3 to 4.5 mm (Hopping 1964; Bright 1976; Wood 1982; USDA Forest Service 1985).

scholarly journals Genetic Dissection of an Elite Rice Hybrid Revealed That Heterozygotes Are Not Always Advantageous for Performance

Genetics ◽  
2002 ◽  
Vol 162 (4) ◽  
pp. 1885-1895
Author(s):  
J P Hua ◽  
Y Z Xing ◽  
C G Xu ◽  
X L Sun ◽  
S B Yu ◽  
...  
Keyword(s):  
Field Trials ◽  
Genetic Dissection ◽  
F2 Population ◽  
Genetic Components ◽  
Large Numbers ◽  
Marker Loci ◽  
Component Traits ◽  
Single Locus Analysis ◽  
Immortalized F2 ◽  
Heterotic Hybrid

Abstract We introduced an experimental design that produced an “immortalized F2” population allowing for complete dissection of genetic components underlying quantitative traits. Data for yield and three component traits of the immortalized F2 were collected from replicated field trials over 2 years. Using 231 marker loci, we resolved the genetic effects into individual components and assessed relative performance of all the genotypes at both single- and two-locus levels. Single-locus analysis detected 40 QTL for the four traits. Dominance effects for about one-half of the QTL were negative, resulting in little “net” positive dominance effect. Correlation between genotype heterozygosity and trait performance was low. Large numbers of digenic interactions, including AA, AD, and DD, were detected for all the traits, with AA as the most prevalent interaction. Complementary two-locus homozygotes frequently performed the best among the nine genotypes of many two-locus combinations. While cumulative small advantages over two-locus combinations may partly explain the genetic basis of heterosis of the hybrid as double heterozygotes frequently demonstrated marginal advantages, double heterozygotes were never the best genotypes in any of the two-locus combinations. It was concluded that heterozygotes were not necessarily advantageous for trait performance even among genotypes derived from such a highly heterotic hybrid.

Analysis of Turee Microscopic Cuaracters for Separating the Wood of Pinus Contorta and P. Ponderosa

IAWA Journal ◽  
2003 ◽  
Vol 24 (3) ◽  
pp. 257-267
Author(s):  
Alex C. Wiedenhoeft ◽  
Regis B. Miller ◽  
Terra J. Theim
Keyword(s):  
Pinus Ponderosa ◽  
Pinus Contorta ◽  
Resin Canal ◽  
Diagnostic Character ◽  
Resin Canals

Three microscopic characters were evaluated for the identification of Pinus contorta and Pinus ponderosa. The tangential diameter of the resin canals, including the epithelium, was compared to the tangential diameter of the entire resin canal complex. The latter measurement was shown to give diagnostic results for these species. Data from the examination of ray composition do not support previously published methods for separating P. contorta and P. ponderosa. The presence or absence of small elongate crystals in the subsidiary parenchyma of the resin canal complexes was shown to be the most powerful diagnostic character for separating the wood of these species.

scholarly journals Planted stock performance 10 years after partial cutting in west-central British Columbia

2010 ◽  
Vol 86 (1) ◽  
pp. 118-129 ◽  
Author(s):  
M J Waterhouse ◽  
E. C. Wallich ◽  
N. M. Daintith ◽  
H. M. Armleder
Keyword(s):  
Picea Glauca ◽  
Group Selection ◽  
Pinus Contorta ◽  
Rangifer Tarandus ◽  
Lodgepole Pine ◽  
Light Level ◽  
Frost Damage ◽  
Partial Cutting ◽  
Partial Harvest ◽  
Interior Spruce

Mature lodgepole pine (Pinus contorta) forests were harvested using group selection (GS) (0.02-ha openings) and irregular group shelterwood (IGS) (0.05-ha openings) systems to maintain arboreal and terrestrial lichens in the winter range of northern woodland caribou (Rangifer tarandus caribou). Ten years after planting, lodgepole pine showed excellent survival, but were smaller in the partial cut openings compared to the clearcuts. Pine grew less in the Sub-Boreal Pine–Spruce biogeoclimatic subzone (SBPSxc) than in the Montane Spruce subzone (MSxv), and trees were smaller in the GS versus IGS treatment within the MSxv subzone. Interior spruce (Picea glauca × engelmannii) grew best in the MSxv and partial cut treatments, but was significantly affected by summer frost in the clearcuts. In an operational-scale Adaptive Management trial, openings were enlarged to 0.15 ha, and both pine and spruce showed excellent survival, minimal frost damage, and 10-year size similar to clearcut conditions. This study suggests that lodgepole pine and interior spruce can be successfully regenerated in partial cut openings with acceptable growth in gaps of 0.15 ha. Key words: caribou, group selection, interior spruce, irregular group shelterwood, light level, lodgepole pine, Montane Spruce zone, partial harvest, soil moisture, soil temperature, Sub-Boreal Pine Spruce zone, summer frost

Stomiopeltis pinastri. [Descriptions of Fungi and Bacteria].

2007 ◽  
Author(s):  
D. W. Minter
Keyword(s):  
New York ◽  
Pinus Ponderosa ◽  
Pinus Contorta ◽  
Pinus Halepensis ◽  
Conservation Status ◽  
Pinus Nigra ◽  
Pinus Monticola ◽  
Pinus Caribaea ◽  
Pinus Roxburghii ◽  
Diagnostic Features

Abstract A description is provided for Stomiopeltis pinastri, which are found on dead pine needles. Details are given of its hosts (Cupressus abramsiana, Juniperus communis, Picea sp., Pinus brutia, Pinus caribaea, Pinus cembra, Pinus contorta, Pinus halepensis, Pinus montezumae, Pinus monticola, Pinus mugo, Pinus muricata, Pinus nigra, Pinus nigra var. austriaca, Pinus nigra var. maritime, Pinus pinaster, Pinus ponderosa, Pinus radiata, Pinus roxburghii, Pinus strobus, Pinus sylvestris, Pinus taeda, Pinus thunbergiana [Pinus thunbergii], Pinus wallichiana and Protium sp.), associated species, geographical distribution (Canada (British Columbia), USA (California, Georgia, New York, North Carolina, Tennessee and Washington), Brazil (Pernambuco), India (Himachal Pradesh and Jammu-Kashmir), Pakistan, Portugal (Azores), Austria, Belgium, Czech Republic, Irish Republic, Finland, France, Germany, UK, Greece, Italy, Netherlands, Poland, San Marino, Spain, Sweden and Switzerland), transmission, diagnostic features and conservation status.

scholarly journals Simultaneous Real-Time Measurement of Isoprene and 2-Methyl-3-Buten-2-ol Emissions From Trees Using SIFT-MS

2020 ◽  
Vol 11 ◽  
Author(s):  
Ann-Sophie Lehnert ◽  
Erica Perreca ◽  
Jonathan Gershenzon ◽  
Georg Pohnert ◽  
Susan E. Trumbore
Keyword(s):  
Mass Spectrometry ◽  
Picea Abies ◽  
Pinus Ponderosa ◽  
Picea Glauca ◽  
Bark Beetles ◽  
Proton Transfer Reaction ◽  
Terrestrial Vegetation ◽  
Plant Groups ◽  
On Line ◽  
Measuring Tool

The C5 hemiterpenes isoprene and 2-methyl-3-buten-2-ol (MBO) are important biogenic volatiles emitted from terrestrial vegetation. Isoprene is emitted from many plant groups, especially trees such as Populus, while emission of MBO is restricted to certain North American conifers, including species of Pinus. MBO is also a pheromone emitted by several conifer bark beetles. Both isoprene and MBO have typically been measured by proton-transfer reaction mass spectrometry (PTR-MS), but this method cannot accurately distinguish between them because of their signal overlap. Our study developed a method for using selective ion flow tube mass spectrometry (SIFT-MS) that allows simultaneous on-line measurement of isoprene and MBO by employing different reagent ions. The use of m/z(NO+) = 68 u for isoprene and m/z(O2+) = 71 u for MBO gave minimal interference between the compounds. We tested the suitability of the method by measuring the emission of young trees of Populus, Picea, and Pinus. Our results largely confirm previous findings that Populus nigra, Picea glauca, and Picea abies emit isoprene and Pinus ponderosa emits MBO, but we also found MBO to be emitted by Picea abies. Thus SIFT-MS provides a reliable, easy to use, on-line measuring tool to distinguish between isoprene and MBO. The method should be of use to atmospheric chemists, tree physiologists and forest entomologists, among others.

Influence of Site Factors on Incidence of Vole and Lemming Feeding Damage to Forest Plantations

1991 ◽  
Vol 6 (3) ◽  
pp. 64-67 ◽  
Author(s):  
Thomas P. Sullivan ◽  
Wayne L. Martin
Keyword(s):  
Picea Glauca ◽  
Pinus Contorta ◽  
Forest Type ◽  
Lodgepole Pine ◽  
Seedling Survival ◽  
Meadow Vole ◽  
Abies Lasiocarpa ◽  
Feeding Damage ◽  
Site Factors ◽  
Average Survival

Abstract The incidence of meadow vole (Microtus pennsylvanicus) and brown lemming (Lemmus sibiricus) feeding damage to young plantations of lodgepole pine (Pinus contorta var. latifolia) and interior spruce (Picea glauca × Picea engelmannii) was studied in west-central British Columbia. Fifty-eight plantations were surveyed for seedling survival and stocking, and an additional 21 older plantations of lodgepole pine were surveyed for tree damage. Average survival of pine (47.7%) was significantly lower than that of spruce (56.0%). Because of mortality from vole feeding, 24 of the 58 plantations were not satisfactorily restocked. Planted trees were attacked significantly more than natural regeneration. Severely attacked plantations occurred in the spruce-subalpine fir (Abies lasiocarpa) forest type at elevations > 800 m on N to NE aspects. Susceptible plantations generally had mechanical or no site preparation with complex post-harvest debris and limited vegetation cover. West. J. Appl. For. 6(3):64-67.

scholarly journals The host spectrum of Dothistroma needle blight Mycosphaerella pini E. Rostrup – new hosts of Dothistroma needle blight observed in theCzech Republic

2012 ◽  
Vol 52 (No. 1) ◽  
pp. 30-36 ◽  
Author(s):  
M. Bednářová ◽  
D. Palovčíková ◽  
L. Jankovský
Keyword(s):  
Czech Republic ◽  
Pinus Ponderosa ◽  
Pinus Banksiana ◽  
Pinus Contorta ◽  
Pinus Nigra ◽  
The Czech Republic ◽  
Christmas Trees ◽  
Dothistroma Needle Blight ◽  
Pinus Aristata ◽  
Needle Blight

Dothistroma needle blight Mycosphaerella pini E. Rostrup and its anamorphic stage Dothistroma septospora (Dorog.) Morelet was detected for the first time in the territory of the Czech Republic in a consignment of imported plants of Austrian pine Pinus nigra Arnold in 1999. In 2000, it was also found on Pinus nigra in an open planting in a plantation of Christmas trees by the village of Jedovnice near Brno in South Moravia. In the Czech Republic, Dothi-stroma needle blight was identified on 13 species of pine. Pinus nigra Arnold and Pinus mugo Turra are the most frequent hosts. In addition to these species, Dothistroma needle blight was observed on Pinus ponderosa Douglas ex Lawson, Pinus jeffreyi Grev. et Balf, Pinus banksiana Lamb., Pinus contorta Douglas, Pinus rotundata Link, Pinus leucodermis Ant. and Pinus sylvestris L. Finds on Pinus aristata Engelm., Pinus rigida Mill., Pinus heldreichii H. Christ. and Pinus cembra L. var. sibirica (Du Tour) G. Don. are a certain rarity. These species are not mentioned anywhere as potential hosts of Dothistroma needle blight. As for the species of other genera Picea pungens Engelm., Picea abies L. Karst. and last but not least Picea schrenkiana Fisch. & C. A. Mey were also observed as hosts. The host range of Dothistroma needle blight recorded in papers is noted as well.

scholarly journals Theoretical and experimental intravascular gas embolism absorption dynamics

1999 ◽  
Vol 87 (4) ◽  
pp. 1287-1295 ◽  
Author(s):  
Annette B. Branger ◽  
David M. Eckmann
Keyword(s):  
Spherical Shape ◽  
Neurological Dysfunction ◽  
Gas Embolism ◽  
Absorption Time ◽  
Large Numbers ◽  
Male Wistar Rats ◽  
End Caps ◽  
Using Data ◽  
Initial Geometry

Multifocal cerebrovascular gas embolism occurs frequently during cardiopulmonary bypass and is thought to cause postoperative neurological dysfunction in large numbers of patients. We developed a mathematical model to predict the absorption time of intravascular gas embolism, accounting for the bubble geometry observed in vivo. We modeled bubbles as cylinders with hemispherical end caps and solved the resulting governing gas transport equations numerically. We validated the model using data obtained from video-microscopy measurements of bubbles in the intact cremaster microcirculation of anesthetized male Wistar rats. The theoretical model with the use of in vivo geometry closely predicted actual absorption times for experimental intravascular gas embolisms and was more accurate than a model based on spherical shape. We computed absorption times for cerebrovascular gas embolism assuming a range of bubble geometries, initial volumes, and parameters relevant to brain blood flow. Results of the simulations demonstrated absorption time maxima and minima based on initial geometry, with several configurations taking as much as 50% longer to be absorbed than would a comparable spherical bubble.

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