The influence of light quality and carbon dioxide enrichment on the growth and physiology of seedlings of three conifer species. II. Physiological responses

1996 ◽  
Vol 74 (3) ◽  
pp. 391-402 ◽  
Author(s):  
John Hoddinott ◽  
Rickey Scott
Keyword(s):  
Chlorophyll Fluorescence ◽  
Picea Mariana ◽  
Picea Glauca ◽  
Pinus Banksiana ◽  
Light Quality ◽  
Growth Period ◽  
Treatment Phase ◽  
Long Day ◽  
Nonstructural Carbohydrate ◽  
Short Days

Pinus banksiana, Picea mariana, and Picea glauca were grown at 350, 700, or 1050 μL∙L−1 CO2 and either high or low red/far-red quantum flux ratios. After a 16-week, long day growth period, seedlings were subjected sequentially to short daylengths, then short days with low temperatures. Various physiological parameters were determined at the end of each treatment phase to monitor how those treatments influenced the onset of seedling dormancy. After the long day treatments, high ratios increased the total chlorophyll content and reduced the original level of chlorophyll fluorescence and the shoot total nonstructural carbohydrate content in very shade-intolerant Pinus banksiana. In shade-tolerant Picea mariana, high CO2 levels caused the main effects on these parameters while neither light quality or CO2 had significant effects on them in shade-tolerant Picea glauca. Short days and low temperature induced a proportional increase in the partitioning of total nonstructural carbohydrate to the roots in all species and produced other species and treatment-specific responses. Keywords: light quality, CO2 enrichment, chlorophyll fluorescence.

The influence of light quality and carbon dioxide enrichment on the growth and physiology of seedlings of three conifer species. I. Growth responses

1996 ◽  
Vol 74 (3) ◽  
pp. 383-390 ◽  
Author(s):  
John Hoddinott ◽  
Rickey Scott
Keyword(s):  
Growth Rates ◽  
Picea Mariana ◽  
Picea Glauca ◽  
Pinus Banksiana ◽  
Light Quality ◽  
Flux Ratio ◽  
Growth Period ◽  
Growth Responses ◽  
Relative Growth ◽  
Relative Growth Rates

Plant growth responds to light quality, as evaluated by the red/far-red (R/FR) quantum flux ratio, and to the level of CO2. Pinus banksiana, Picea mariana and Picea glauca seedlings were raised at 350, 700, or 1050 μL∙L−1 CO2 and high or low R/FR ratios and growth was measured over a 16-week growth period. Far-red rich light enhanced the whole plant and height relative growth rates of Pinus banksiana. The three species showed species specific responses in plant organ relative growth rates and partitioning ratios. On the basis of their biomass partitioning the species would be ranked Pinus banksiana < Picea mariana < Picea glauca for shade tolerance. In commercial operations, seedlings grown for outplanting are selected, in part, on the basis of plant form as described by the stem height/diameter ratio. More desirable ratios were obtained at ambient CO2 concentrations for Pinus banksiana and Picea mariana in red rich light and for Picea glauca in far-red rich light. Keywords: seedling growth, light quality, CO2 enrichment.

Short-term effects of cut-to-length versus full-tree harvesting on conifer regeneration in jack pine, mixedwood, and black spruce forests in Manitoba

2004 ◽  
Vol 34 (9) ◽  
pp. 1938-1945 ◽  
Author(s):  
Isobel Waters ◽  
Steven W Kembel ◽  
Jean-François Gingras ◽  
Jennifer M Shay
Keyword(s):  
Picea Mariana ◽  
Picea Glauca ◽  
Pinus Banksiana ◽  
Black Spruce ◽  
Abies Balsamea ◽  
Jack Pine ◽  
Tree Regeneration ◽  
Understorey Vegetation ◽  
Advance Regeneration ◽  
The Impact

This study compares the effects of full-tree versus cut-to-length forest harvesting methods on tree regeneration in jack pine (Pinus banksiana Lamb.), mixedwood (Picea glauca (Moench) Voss – Populus tremuloides Michx. – Abies balsamea (L.) Mill.), and black spruce (Picea mariana (Mill.) BSP) sites in southeastern Manitoba, Canada. We surveyed tree regeneration densities, disturbance characteristics, and understorey vegetation in replicated control and harvested plots in each site type preharvest (1993) and 1 and 3 years postharvest (1994, 1996). In jack pine sites, the full-tree harvest method promoted regeneration of Pinus banksiana through increased disturbance of soil and the moss layer, and decreased slash deposition relative to the cut-to-length method. Conversely, in mixedwood sites the cut-to-length method resulted in less damage to advance regeneration and proved better at promoting postharvest regeneration of Abies balsamea and Picea glauca relative to the full-tree method. In black spruce sites, there were few differences in the impact of the two harvesting methods on regeneration of Picea mariana, which increased in frequency and density after both types of harvesting.

The effect of salinity on the emergence and seedling growth of Picea mariana, Picea glauca, and Pinus banksiana

2001 ◽  
Vol 115 (1) ◽  
pp. 9-16 ◽  
Author(s):  
C Croser ◽  
S Renault ◽  
J Franklin ◽  
J Zwiazek
Keyword(s):  
Seedling Growth ◽  
Picea Mariana ◽  
Picea Glauca ◽  
Pinus Banksiana

Effects of Root Freezing on the Physiology and Growth of Picea glauca, Picea mariana and Pinus banksiana Seedlings Under Different Soil Moisture Regimes

2002 ◽  
Vol 17 (3) ◽  
pp. 206-217 ◽  
Author(s):  
Carole Coursolle ◽  
Francine J. Bigras ◽  
Hank A. Margolis
Keyword(s):  
Soil Moisture ◽  
Picea Mariana ◽  
Picea Glauca ◽  
Pinus Banksiana ◽  
Moisture Regimes

Red and far-red light influence carbon partitioning, growth and flowering of bahia grass (Paspalum notatum)

1995 ◽  
Vol 125 (3) ◽  
pp. 355-359 ◽  
Author(s):  
F. J. Marousky ◽  
F. Blondon
Keyword(s):  
Light Quality ◽  
Dark Period ◽  
Leaf Growth ◽  
Red Light ◽  
Dry Weight ◽  
Paspalum Notatum ◽  
Starch Accumulation ◽  
Long Day ◽  
Bahia Grass ◽  
Short Days

SUMMARYBahia grass (Paspalum notatum Flugge) plants were grown in growth chambers at Gif, France, and at Gainesville in Florida, demonstrating that the species is a long-day plant and greatly influenced by light quality during the photosynthetic period. Flowering occurred in all instances when the middle of the dark period was interrupted with red or red + far-red light. With nightly interruptions of farred light, flowering occurred only when a sufficient quantity of far-red was present during the photosynthetic period. Plants grown under short days with nightly interruptions of red, far-red or red + far-red light had less starch accumulation and greater leaf growth and dry weight than plants grown without nightly light interruptions, whatever the light quality during the photosynthetic period. The treatments did not affect the partitioning of assimilates and flowering in the same way.

Fungi that cause sapstain in Canadian softwoods

1999 ◽  
Vol 45 (11) ◽  
pp. 914-922 ◽  
Author(s):  
A Uzunovic ◽  
D -Q Yang ◽  
P Gagné ◽  
C Breuil ◽  
L Bernier ◽  
...  
Keyword(s):  
Picea Mariana ◽  
Picea Glauca ◽  
Pinus Banksiana ◽  
Pinus Contorta ◽  
Abies Balsamea ◽  
Forest Products ◽  
Fungal Species ◽  
Forest Products Industry ◽  
Diverse Range ◽  
Commercially Important

The Canadian forest products industry suffers considerable losses due to discoloration caused by sapstain fungi. Although studied for a number of years, the identity, biology, and ecology of these fungi are still only partly understood. To determine which fungi caused stain problems, a detailed survey was conducted at seven selected sawmills across Canada. In summer 1997, fresh logs and lumber were set aside in the mills 1 month prior to sampling for fungi. We excluded bark-beetle-attacked wood and our logs remained free from their attack during storage. Five commercially important softwood species, Abies balsamea (L.) Mill., Picea mariana (Mill.) B.S.P., Picea glauca (Moench) Voss, Pinus contorta Dougl., and Pinus banksiana Lamb., were included in the studies. A total of 1863 isolates were isolated from stained and adjacent areas on test wood, and were identified based on their morphological and physiological characteristics and mating compatibility to 13 different species representing five genera. The most commonly encountered genus, Ophiostoma (97%), was represented by nine species. A more diverse range of fungi was found in logs than in lumber; some species were more frequently isolated from one type of substrate and rarely (or not at all) from the other. No fungal species occurred exclusively in a particular region or wood substrate.Key words: bluestain, lumber, logs, Ophiostoma, Ceratocystis.

Effects of fire severity on early survival and growth of planted jack pine, black spruce and white spruce

2010 ◽  
Vol 86 (2) ◽  
pp. 193-199 ◽  
Author(s):  
G. Geoff Wang ◽  
Kevin J Kemball
Keyword(s):  
Seedling Growth ◽  
Picea Mariana ◽  
Picea Glauca ◽  
Pinus Banksiana ◽  
Black Spruce ◽  
Fire Severity ◽  
White Spruce ◽  
Jack Pine ◽  
Survival And Growth ◽  
Early Survival

Two boreal mixedwood stands burned by the 1999 Black River wildfire in southeastern Manitoba, Canada were selected to study the effect of fire severity on early survival and growth of planted jack pine (Pinus banksiana), black spruce (Picea mariana) and white spruce (Picea glauca) seedlings. In each stand, three fire severity classes (scorched, lightly burned, and severely burned) were identified based on the degree of forest floor consumption. Fire severity was not a significant factor on mortality. No mortality difference was found among species, except for year 5 when jack pine had significantly higher mortality than both black spruce and white spruce. Jack pine and black spruce had their highest mortality in year 4, while white spruce had its highest mortality in year 1. Under natural competition, seedling growth increased with increasing fire severity. When competition was removed, fire severity did not affect seedling growth. Regardless of fire severity and competition, jack pine had better diameter and height growth than black spruce, which, in turn, grew slightly taller than white spruce. Planted seedlings faced less intense vegetation competition on severely burned plots compared to scorched or lightly burned plots. Regardless of fire severity and species, competition increased with time since planting. Our study results indicate that planting immediately after a wildfire is a viable option to establish conifer components on burned boreal mixedwood stands. Key words: fire severity, plantation, regeneration, Pinus banksiana, Picea mariana, Picea glauca

scholarly journals Vegetation of the Continental Northwest Territories at 6 ka BP

2007 ◽  
Vol 49 (1) ◽  
pp. 37-43 ◽  
Author(s):  
Glen M. MacDonald
Keyword(s):  
Northwest Territories ◽  
Populus Tremuloides ◽  
Picea Mariana ◽  
Picea Glauca ◽  
Pinus Banksiana ◽  
Arctic Tundra ◽  
Range Limits ◽  
Mackenzie Delta ◽  
Delta Region ◽  
Low Arctic

ABSTRACTPollen records are used to reconstruct vegetation in the continental Northwest Territories at 6 ka (6000 14C yr BP). Picea glauca, P mariana, Larix laricina, Populus tremuloides, P. balsamifera, Alnus crispa and A. incana were present throughout their modern ranges in the Boreal and Subarctic Forest Zones by 6000 BP. Pinus banksiana, however, had not yet reached its present northern limits. Population densities of the dominant trees, Picea glauca and Picea mariana, were close to, or as high as, present. In the Mackenzie Delta region the range limit of Picea glauca was approximately 25 km north of its modern location just prior to 6000 BP. In contrast, the northern limits of the forest in central Canada were similar to present. The tundra vegetation close to the edge of the forest was similar to modern Low Arctic Tundra. Development of extensive Sphagnum peatlands had begun in the forested areas and the adjacent Low Arctic Tundra. Palaeoecological information regarding vegetation at 6000 BP remains lacking for the northeastern half of the study area. Therefore, the nature of the vegetation in much of the area now occupied by Low Arctic and Middle Arctic Tundra remains unknown. Important vegetation changes that occurred following 6 ka include : (1) the advance of Pinus banksiana to its present northern range limits, (2) the retreat of the northern range limits of Picea glauca in the Mackenzie Delta region between 6000 and 3500 BP and (3) the rapid and marked increase in the population density of Picea mariana in the treeline zone of the central Northwest Territories at 5000 BP followed by a decline at 4000 BP.

Cree antidiabetic plant extracts display mechanism-based inactivation of CYP3A4

2011 ◽  
Vol 89 (1) ◽  
pp. 13-23 ◽  
Author(s):  
Teresa W. Tam ◽  
Rui Liu ◽  
John T. Arnason ◽  
Anthony Krantis ◽  
William A. Staines ◽  
...  
Keyword(s):  
Medicinal Plants ◽  
Picea Mariana ◽  
Picea Glauca ◽  
Pinus Banksiana ◽  
Abies Balsamea ◽  
Cytochrome P450 3A4 ◽  
Cyp3a4 Inhibition ◽  
Kalmia Angustifolia ◽  
Lycopodium Clavatum ◽  
Rhododendron Tomentosum

Seventeen Cree antidiabetic medicinal plants were studied to determine their potential to inhibit cytochrome P450 3A4 (CYP3A4) through mechanism-based inactivation (MBI). The ethanolic extracts of the medicinal plants were studied for their inhibition of CYP3A4 using the substrates testosterone and dibenzylfluorescein (DBF) in high pressure liquid chromatography (HPLC) and microtiter fluorometric assays, respectively. Using testosterone as a substrate, extracts of Alnus incana , Sarracenia purpurea , and Lycopodium clavatum were identified as potent CYP3A4 MBIs, while those from Abies balsamea , Picea mariana , Pinus banksiana , Rhododendron tomentosum , Kalmia angustifolia , and Picea glauca were identified as less potent inactivators. Not unexpectedly, the other substrate, DBF, showed a different profile of inhibition. Only A. balsamea was identified as a CYP3A4 MBI using DBF. Abies balsamea displayed both NADPH- and time-dependence of CYP3A4 inhibition using both substrates. Overall, several of the medicinal plants may markedly deplete CYP3A4 through MBI and, consequently, decrease the metabolism of CYP3A4 substrates including numerous medications used by diabetics.

THE VEGETATION OF NORTHERN MANITOBA: I. STUDIES IN THE SOUTHERN SPRUCE FOREST ZONE

1956 ◽  
Vol 34 (4) ◽  
pp. 523-561 ◽  
Author(s):  
J. C. Ritchie
Keyword(s):  
North America ◽  
Picea Mariana ◽  
Picea Glauca ◽  
Pinus Banksiana ◽  
Local Community ◽  
Ground Vegetation ◽  
Spruce Forest ◽  
Betula Papyrifera ◽  
Eastern Canada ◽  
Forest Zone

It is pointed out that there are available no ecological accounts of the vegetation of Northern Manitoba and the surrounding regions. After brief accounts of the topography, geology, and climate, the communities which were met with in two areas of study are described. It is shown that the predominant and stable forest of mesic sites is dominated by Picea mariana, with a ground vegetation composed chiefly of weft-form mosses. In areas which have been burned various subseral variants of this forest are present. Pinus banksiana, as well as being a seral dominant of mesic sites, dominates various forests of outcrop ridges, sand plains, and eskers. Picea glauca is rare in the area, occurring only on those sites which show exceptionally favourable conditions of habitat. The vegetation of this region conforms with descriptions of the Southern Spruce Forest Zone of Eastern Canada, which classification might well be extended westwards at least as far as northwest Manitoba. There is some evidence that the dry climate which prevails west of the region, and for which there is slight evidence here, has influenced the flora and vegetation of the region. A description is given of a highly local community of Betula papyrifera var. neoalaskana on organic ridges which appears never to have been recorded previously for North America.

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