Genetic variation and productivity of Populus trichocarpa and its hybrids. X. Trait correlations in young black cottonwood from four river valleys in Washington

Epidermal and stomatal cell traits were examined on late leaves of 40 black cottonwood (Populus trichocarpa Torr. & Gray) clones originating from the mesic Nisqually, and xeric Yakima river valleys of Washington. Four leaves per clone were collected from 1-year-old trees in two replicated common gardens located in Puyallup (western Washington) and Wenatchee (eastern Washington). In Puyallup-grown material, Yakima clones had abaxially 14% smaller epidermal cell diameters (CDIAM) and 27% greater cell densities (CDEN; No. per mm2), and 25% smaller leaves than Nisqually clones (p [Formula: see text] 0.03). Abaxial stomatal densities (STDEN; No. per mm2) were highest (206) in the lower elevation, xeric-origin Yakima clones, as compared with an average of 120 in Nisqually clones. A higher proportion of Yakima leaves had shorter stomates than those from the Nisqually at both sites (p [Formula: see text] 0.002). Besides shorter stomates (p [Formula: see text] 0.030), the lower elevation Yakima clones generally had higher STDEN and ratios of STDEN to CDEN than those clones from the upper group (p [Formula: see text] 0.098). Acclimation of Wenatchee-grown clones to the hotter, drier summer climate was also evident, as they generally had smaller CDIAM, and higher CDEN and STDEN than those grown at Puyallup. Genetic variances (among rivers, groups within river, and clones within group within river) ranged from 42 to 84% with clone being dominant for epidermal traits while the other two components were dominant for stomatal traits. In the Yakima leaves, much of the genetic variance (group and clone within group) resided in the group component. Broad-sense heritabilities averaged 72%, indicating moderately strong genetic control in most traits. This study provides further evidence of genetic variation in P. trichocarpa at the regional and local scales across the Washington Cascades.Key words: Populus trichocarpa, black cottonwood, stomata, adaptation, acclimation, genetic variation.

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Intraspecific variation in photosynthetic traits of Populus trichocarpa

Canadian Journal of Botany ◽

10.1139/b93-156 ◽

1993 ◽

Vol 71 (10) ◽

pp. 1304-1311 ◽

Cited By ~ 16

Author(s):

J. M. Dunlap ◽

J. H. Braatne ◽

T. M. Hinckley ◽

R. F. Stettler

Keyword(s):

Water Use Efficiency ◽

Water Use ◽

Populus Trichocarpa ◽

High Light ◽

Black Cottonwood ◽

Photosynthetic Rates ◽

Light Levels ◽

Lower Elevation ◽

Use Efficiency ◽

River Valleys

Three experiments were conducted to evaluate net photosynthesis in black cottonwood (Populus trichocarpa Torrey & Gray) from mesic and xeric regions of Washington. In 1986, six clones each from the lower Nisqually (mesic) and Yakima (xeric) river valleys and growing in a common garden were measured for their photosynthetic rates. On 2 clear days in summer, Yakima clones had significantly (p ≤ 0.10) higher rates (means: 32 and 25μmol CO2 m−2 s−1) than Nisqually clones (means: 25 and 22μmol CO2 m−2 s−1). The next year, cuttings from these clones were potted, grown separately for 2 months in a maritime (Puyallup, Wash.) and a continental climate (Wenatchee, Wash.), and then transferred to growth chambers in Seattle, Wash. Photosynthetic rates were determined at four light levels (200, 500, 800, and 1500 μmol m−2 s−1) and two temperatures (24 and 32 °C). Yakima plants had significantly (p ≤ 0.05) higher rates at high light (20μmol CO2 m−2 s−1) and also at moderate light in high temperature than Nisqually plants (16 μmol CO2 m−2 s−1 in high light). Significant acclimation (p ≤ 0.01) was also revealed: at the two moderate light levels in high temperatures the Wenatchee-grown plants, regardless of source, had higher rates than those grown at Puyallup. In 1991, eight clones from the lower elevation, xeric region of the Yakima and eight from the upper elevation, mesic region were selected in a Puyallup stoolbed, and their photosynthesis and water-use efficiency were measured on a clear summer day. Lower elevation plants had a higher photosynthetic rate than those from the upper elevations along the Yakima; values were similar to those of 1986. The pattern for water-use efficiency was reversed; values were 56 μmol CO2/mol H2O for the lower and 84 μmol CO2/mol H2O for the upper Yakima plants. These three experiments provide evidence for significant genetic variation in photosynthetic processes both between and within river valleys. Key words: Populus trichocarpa, black cottonwood, poplar, photosynthesis, water-use efficiency, adaptation.

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Genetic variation and productivity of Populustrichocarpa and its hybrids. VII. Two-year survival and growth of native black cottonwood clones from four river valleys in Washington

Canadian Journal of Forest Research ◽

10.1139/x94-201 ◽

1994 ◽

Vol 24 (8) ◽

pp. 1539-1549 ◽

Cited By ~ 10

Author(s):

J.M. Dunlap ◽

P. E. Heilman ◽

R.F. Stettler

Keyword(s):

Genetic Variation ◽

Common Garden ◽

Stem Volume ◽

Black Cottonwood ◽

Tarnished Plant Bug ◽

Selection Gradient ◽

Genetic Components ◽

Lower Elevation ◽

Microsite Heterogeneity ◽

River Valleys

A common-garden study of Populustrichocarpa Torr. & Gray was initiated in 1985 when clonal material from 128 trees was collected from sites distributed along two mesic (Hoh and Nisqually) and two xeric (Dungeness and Yakima) river valleys. This material was grown for 1 year at Puyallup, Wash. In spring 1986, cuttings from this material were used to establish two replicate plantations, one at Puyallup and one at Wenatchee, Wash. Over the 2 year period, trees were assessed for survival, damage, and growth. Two-year survival was 86% at Puyallup and 59% at Wenatchee; survival was higher for mesic-origin trees at both sites. At Wenatchee, mortality was mainly due to a droughty soil and hot, dry climate in the first year, and damage was due to the tarnished plant bug (Lygus spp.), field voles (Microtus spp.), and grasshoppers (Family Acrididae). At both locations, Melampsoraoccidentalis Jacks. leaf rust was found mainly on trees originating from Yakima. Mean 2-year height and diameter at Puyallup were 457 cm and 40 mm, respectively; corresponding values at Wenatchee were 320 cm and 29 mm. At Puyallup, 2-year stem volume (diameter2 × height) decreased significantly in this order: Nisqually (13 500 cm3) = Hoh > Dungeness > Yakima (4700 cm3). Within the Nisqually trees, clones from lower, milder climate elevations grew more than those from the upper elevations. The reverse was true for the Yakima trees, presumably because the lower elevation trees are adapted to an arid climate and are very susceptible to Melampsora rust. At Wenatchee, high microsite heterogeneity masked much of the genetic variation. The genetic variance component (among rivers, sites, and clones) for stem volume at Puyallup increased from 27 to 51% over the second year. In analyses of each river valley, genetic components (elevational group and clone) were also high at 27–63%; however, for the Yakima trees, the elevational group variance (40%) was much larger than for the other valleys (0–7%) and suggests a steep selection gradient midway along the river transect.

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A peroxisomal β-oxidative pathway contributes to the formation of C6–C1 aromatic volatiles in poplar

Plant Physiology ◽

10.1093/plphys/kiab111 ◽

2021 ◽

Author(s):

Nathalie D Lackus ◽

Axel Schmidt ◽

Jonathan Gershenzon ◽

Tobias G Köllner

Keyword(s):

Cinnamic Acid ◽

Aromatic Compounds ◽

Populus Trichocarpa ◽

Alternative Pathway ◽

Gene Families ◽

Defense Responses ◽

In Planta ◽

Black Cottonwood ◽

Oxidative Pathway

AbstractBenzenoids (C6–C1 aromatic compounds) play important roles in plant defense and are often produced upon herbivory. Black cottonwood (Populus trichocarpa) produces a variety of volatile and nonvolatile benzenoids involved in various defense responses. However, their biosynthesis in poplar is mainly unresolved. We showed feeding of the poplar leaf beetle (Chrysomela populi) on P. trichocarpa leaves led to increased emission of the benzenoid volatiles benzaldehyde, benzylalcohol, and benzyl benzoate. The accumulation of salicinoids, a group of nonvolatile phenolic defense glycosides composed in part of benzenoid units, was hardly affected by beetle herbivory. In planta labeling experiments revealed that volatile and nonvolatile poplar benzenoids are produced from cinnamic acid (C6–C3). The biosynthesis of C6–C1 aromatic compounds from cinnamic acid has been described in petunia (Petunia hybrida) flowers where the pathway includes a peroxisomal-localized chain shortening sequence, involving cinnamate-CoA ligase (CNL), cinnamoyl-CoA hydratase/dehydrogenase (CHD), and 3-ketoacyl-CoA thiolase (KAT). Sequence and phylogenetic analysis enabled the identification of small CNL, CHD, and KAT gene families in P. trichocarpa. Heterologous expression of the candidate genes in Escherichia coli and characterization of purified proteins in vitro revealed enzymatic activities similar to those described in petunia flowers. RNA interference-mediated knockdown of the CNL subfamily in gray poplar (Populus x canescens) resulted in decreased emission of C6–C1 aromatic volatiles upon herbivory, while constitutively accumulating salicinoids were not affected. This indicates the peroxisomal β-oxidative pathway participates in the formation of volatile benzenoids. The chain shortening steps for salicinoids, however, likely employ an alternative pathway.

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Organ culture with black cottonwood: morphogenetic response of female catkin primordia

Canadian Journal of Botany ◽

10.1139/b72-200 ◽

1972 ◽

Vol 50 (7) ◽

pp. 1627-1631 ◽

Cited By ~ 15

Author(s):

K. S. Bawa ◽

R. F. Stettler

Keyword(s):

Organ Culture ◽

Vegetative Growth ◽

Callus Formation ◽

Populus Trichocarpa ◽

General Tendency ◽

Black Cottonwood ◽

Axillary Shoots ◽

Female Sex ◽

Female Catkin

Female catkin primordia of black cottonwood (Populus trichocarpa T. & G. ex Hook.) were cultured for 70 days on a modified Murashige and Skoog's (1962) medium in vitro. Explants 2–3 mm long, and with bud scales removed, gave the best results, many of them developing floral structures characteristic of the female sex. There was a general tendency to callus formation with increasing age of the culture, occasionally followed by a reversal to vegetative growth. Catkin primordia raised on Wolter's medium without auxin or kinetin, but with 6-benzylaminopurine, and at 250 ft-c for a 16-h photoperiod, proliferated axillary shoots in loco of pistils.

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Ecotypic mode of regional differentiation caused by restricted gene migration: a case in black cottonwood (Populus trichocarpa) along the Pacific Northwest coast

Canadian Journal of Forest Research ◽

10.1139/x08-190 ◽

2009 ◽

Vol 39 (3) ◽

pp. 519-525 ◽

Cited By ~ 34

Author(s):

Chang-Yi Xie ◽

Cheng C. Ying ◽

Alvin D. Yanchuk ◽

Diane L. Holowachuk

Keyword(s):

Genetic Differentiation ◽

Pacific Northwest ◽

Populus Trichocarpa ◽

Common Garden ◽

Northern Region ◽

Regional Differentiation ◽

Black Cottonwood ◽

Gene Migration ◽

Geographic Patterns ◽

Leaf Flushing

Genetic differentiation of black cottonwood ( Populus balsamifera subsp. trichocarpa (Torr. & A. Gray ex Hook) Brayshaw) across a “no-cottonwood” belt on the coast of central British Columbia (BC), Canada, was examined using data on 3 year height, severity of infection by Valsa sordida Nitschke and Melampsora occidentalis H. Jacks., and abnormality of leaf flushing. The data were collected in a common-garden test consisting of 180 provenances of 36 drainages ranging from northern BC to Oregon, USA. The results demonstrated an ecotypic mode, north–south regional differentiation. Valsa sordida and M. occidentalis infected 41% and 89%, respectively, of the trees from the northern region, while 66% showed flushing abnormality. In contrast, only 1% and 27% of their southern counterparts were infected by the same diseases, and 1% had abnormal flushing. Trees from the northern region averaged 87% shorter than those from the south. Regional differentiation accounted for the highest amount of variation observed in all traits, with 60% in 3 year height, 34% in V. sordida, 76% in M. occidentalis, and 50% in abnormal leaf flushing. Regression analysis revealed geographic patterns that essentially reflected regional differentiation along the no-cottonwood belt. The species’ distribution biography, ecological characteristics, and life history suggest that restricted gene migration was the main factor responsible for the observed geographic patterns of genetic differentiation.

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Preemergence Control of Black Cottonwood in Nursery Containers

Journal of Environmental Horticulture ◽

10.24266/0738-2898-27.1.51 ◽

2009 ◽

Vol 27 (1) ◽

pp. 51-55

Author(s):

James E. Altland

Keyword(s):

Populus Trichocarpa ◽

Effective Control ◽

Black Cottonwood ◽

Cottonwood Trees ◽

Preemergence Herbicides

Abstract Two experiments were conducted to evaluate preemergence herbicides for control of black cottonwood (Populus trichocarpa) in nursery containers. In 2006, granular preemergence herbicides were applied to recently filled, weed-free containers in May just prior to seed release from mature cottonwood trees. Flumioxazin provided the most effective cottonwood control, although control with isoxaben + trifluralin, oxyfluorfen + oryzalin, and pendimethalin was also effective. In 2007, containers were filled February 15, and herbicides were applied to separate groups of containers on February 22, March 14, April 16, and May 15. Containers were over-seeded with cottonwood for a 2-week period starting on May 16. Control with most herbicides improved as the date of application neared the date of seeding. Flumioxazin provided the most effective control throughout the experiment, but control from it also improved as the date of application neared the time of seeding.

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Simulating Succession of Riparian Spruce Forests and White-Tailed Deer Carrying Capacity in Northwestern Montana

Western Journal of Applied Forestry ◽

10.1093/wjaf/2.3.80 ◽

1987 ◽

Vol 2 (3) ◽

pp. 80-83 ◽

Cited By ~ 1

Author(s):

Kurt J. Jenkins ◽

R. Gerald Wright

Keyword(s):

Carrying Capacity ◽

River Flow ◽

Populus Trichocarpa ◽

Timber Harvesting ◽

Resource Monitoring ◽

Black Cottonwood ◽

Winter Range ◽

Erosion Rates ◽

The North ◽

North Fork

Abstract Rates of succession were determined during the period 1945-80 in six floodplain plant communities along the North Fork of the Flathead River, Montana. A succession model was developed to forecast the long-range effects of land-use change on the carrying capacity of white-tailed deer winter range. The areas occupied by mature spruce (Picea englemannii x glauca hybrid) and spruce-black cottonwood (Populus trichocarpa) forests on the floodplain were relatively constant between 1945-1980. Early seral types were more variable due to short-term variations in river flow. Successional modelling demonstrated the effects of two timber harvesting strategies on white-tailed deer populations. Simulated populations declined following two timber harvesting schedules, but recovered after cessation of harvest. An additional application of the model showed the potential effects of increased erosion rates on deer populations and demonstrated the versatility of land succession models for resource monitoring. West. J. Appl. For. 2(3):80-83, July 1987

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Conservative plumage masks extraordinary phylogenetic diversity in the Grallaria rufula (Rufous Antpitta) complex of the humid Andes

The Auk ◽

10.1093/auk/ukaa009 ◽

2020 ◽

Vol 137 (3) ◽

Author(s):

R Terry Chesser ◽

Morton L Isler ◽

Andrés M Cuervo ◽

C Daniel Cadena ◽

Spencer C Galen ◽

...

Keyword(s):

Mitochondrial Dna ◽

Genetic Variation ◽

Genetic Differentiation ◽

Genetic Divergence ◽

Phylogenetic Diversity ◽

Biological Species ◽

Cryptic Speciation ◽

Species Groups ◽

River Valleys ◽

Prime Location

Abstract The Grallaria rufula complex is currently considered to consist of 2 species, G. rufula (Rufous Antpitta) and G. blakei (Chestnut Antpitta). However, it has been suggested that the complex, populations of which occur in humid montane forests from Venezuela to Bolivia, comprises a suite of vocally distinct yet morphologically cryptic species. We sequenced nuclear and mitochondrial DNA for 80 individuals from across the distribution of the complex to determine the extent of genetic variation between and within described taxa. Our results revealed 18 geographically coherent clades separated by substantial genetic divergence: 14 within rufula, 3 within blakei, and 1 corresponding to G. rufocinerea (Bicolored Antpitta), a species with distinctive plumage found to be nested within the complex. Neither G. rufula nor G. blakei as presently defined was monophyletic. Although 6 of the 7 recognized subspecies of G. rufula were monophyletic, several subspecies contained substantial genetic differentiation. Genetic variation was largely partitioned across recognized geographic barriers, especially across deep river valleys in Peru and Colombia. Coalescent modeling identified 17 of the 18 clades as significantly differentiated lineages, whereas analyses of vocalizations delineated 16 biological species within the complex. The G. rufula complex seems unusually diverse even among birds of the humid Andes, a prime location for cryptic speciation; however, the extent to which other dispersal-limited Andean species groups exhibit similar degrees of cryptic differentiation awaits further study.

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