Effect of altitude on resource allocation in the weed Achillea millefolium (yarrow, Asteraceae) in the Australian Alps

2004 ◽  
Vol 52 (5) ◽  
pp. 639 ◽  
Author(s):  
Frances Mary Johnston ◽  
Catherine Marina Pickering
Keyword(s):  
Biomass Allocation ◽  
Dry Weight ◽  
Achillea Millefolium ◽  
Reproductive Structures ◽  
Australian Alps ◽  
Allocation Patterns ◽  
Below Ground ◽  
Total Dry Weight ◽  
Environmental Weed ◽  
Ground Structures

Increasing severity of environment associated with increasing altitude in mountain ecosystems (decreasing temperature, increasing duration of snow cover) can affect relative and absolute biomass-allocation patterns in plants. Biomass allocation was examined along a 620-m altitudinal gradient in the Australian Alps for the important environmental weed Achillea millefolium (L., Asteraceae, yarrow). Relative and absolute biomass allocation (dry weight) to reproductive (capitula, flowering stems and associated leaves), vegetative (leaves not on the flowering stem) and below-ground structures (rhizome and roots) were measured at each of nine sites by using quadrats. Increasing altitude resulted in a decrease in relative and absolute allocation of biomass to reproductive structures. For example, the dry weight of inflorescences declined as altitude increased because of a decrease in the weight of the terminal and side branches of the inflorescences, but not the total number of capitula produced. There was also a trend for increased relative allocation to below-ground structures with increasing altitude, even though altitude did not affect absolute allocation to below-ground and vegetative structures, or the total dry weight of A. millefolium. These results are consistent with those for other species growing at high altitude. The management implications for the control of A. millefolium in the Australian Alps are discussed, including in relation to predicted climatic change.

Biennial wormwood (Artemisia biennis) biomass allocation and seed production

Weed Science ◽  
2004 ◽  
Vol 52 (2) ◽  
pp. 246-254 ◽  
Author(s):  
Kris J. Mahoney ◽  
George O. Kegode
Keyword(s):  
Seed Production ◽  
Great Plains ◽  
Biomass Allocation ◽  
Field Experiments ◽  
Dry Weight ◽  
Day Length ◽  
Northern Great Plains ◽  
Allocation Patterns ◽  
Total Dry Weight ◽  
Photoperiod Sensitive

Biennial wormwood has become an important weed problem in the northern Great Plains, but little is known about its biology. Biennial wormwood seeds were collected from Fargo, ND, and Fergus Falls, MN, for field experiments in 1999 and 2000 to determine the influence of transplanting date on growth, biomass, and seed production. Seeds were seeded in a greenhouse every 2 wk, and seedling rosettes were transplanted to the field 2 wk after emergence from April 30 until September 15 to simulate season-long emergence. Weekly destructive subsampling started 2 wk after transplanting and ended on September 29 in both years. All seedlings that grew for at least 5 wk after transplanting produced flowers by mid- to late August of the same year. Late-transplanted seedlings with less than 5 wk of growth did not flower or survive the winter. Biennial wormwood biomass allocation patterns resemble those of an annual species, with about 15% of the total dry weight allocated to roots, 20% to stems, 25% to leaves, and 40% to flowers. Transplant date had a substantial influence on biomass partitioning. Seedlings transplanted early in the growing season produced more biomass and seed than late-season transplants. Biennial wormwood seedlings transplanted on April 30 produced over 435,000 seeds per plant, whereas seedlings transplanted on August 15 produced 500 to 3,000 seeds. Biennial wormwood was photoperiod sensitive and flowered when the day length was about 14 h or less, between August 18 and 25, in both years.

Structural changes in a Hieracium floribundum (Compositae) population associated with the process of patch formation

1978 ◽  
Vol 56 (1) ◽  
pp. 1-9 ◽  
Author(s):  
R. J. Reader
Keyword(s):  
Standing Crop ◽  
Structural Changes ◽  
Vegetative Reproduction ◽  
Light Availability ◽  
Dry Weight ◽  
Genetic Change ◽  
Allocation Pattern ◽  
Southern Ontario ◽  
Reproductive Structures ◽  
Allocation Patterns

The contribution of yellow devil hawkweed (H. floribundum) to the total standing crop of an abandoned pasture in southern Ontario increased from approximately 8% to 70% as H. floribundum colonized the pasture by forming patches containing as many as 3400 rosettes/m2. Within the hawkweed population, there was a significant (P < 0.05) shift in the distribution of standing crop from reproductive to vegetative structures and within the vegetative structures from leaves to roots and rhizome during the process of patch formation. These shifts presumably occurred in response to changing environmental conditions (i.e., increasing light availability, reduced soil moisture levels, greater intraspecific competition). The mechanism by which the allocation pattern changed was more likely phenotypic plasticity than genetic change since H. floribundum is an apomict and vegetative reproduction accounted for most recruitment into the population.The frequency distribution of population members in dry weight classes became more negatively skewed during the process of patch formation, but the distribution did not approach log-normality as predicted in some studies. Significant (P < 0.05) differences were observed in the allocation patterns of individuals belonging to different weight classes in the population. Only the largest plants in the population allocated dry weight to reproductive structures.

The effects of shade on growth, development, and resource allocation patterns of three species of foxtail (Setaria)

1981 ◽  
Vol 59 (9) ◽  
pp. 1776-1786 ◽  
Author(s):  
Susanna M. Lee ◽  
Paul B. Cavers
Keyword(s):  
Reproductive Effort ◽  
Dry Weight ◽  
Relative Increase ◽  
Tiller Number ◽  
Setaria Viridis ◽  
Setaria Glauca ◽  
Allocation Patterns ◽  
Growth Development ◽  
Total Dry Weight ◽  
Lower Tolerance

Three weedy foxtail species, Setaria glauca (L.) Beauv., S. verticillata (L.) Beauv., and S. viridis (L.) Beauv. occur in southwestern Ontario. Plants of the three species were grown in pure stands in the open and under one, two, or three layers of cheesecloth which transmitted 71, 40, and 19% of incident insolation, respectively. Six harvests were taken between July and September in which height, tiller number, dry weight of component parts, and leaf area were determined for randomly selected plants of each species. In unshaded conditions, S. verticillata was the tallest species and had the greatest total dry weight per plant. However, this species was the most adversely affected by shade, with significant reductions in tiller number, biomass production, and reproductive effort with increasing shade. Setaria viridis and S. verticillata exhibited a relative increase in allocation to leaves with increasing shade while S. glauca had a relative increase to stems, indicating different strategies in response to shade. The apparent lower tolerance of shade in S. verticillata may help to explain the comparative rarity of this species in southwestern Ontario.

scholarly journals 294 SINK ACTIVITY AND CARBOHYDRATE ALLOCATION PATTERNS WITHIN DEVELOPING APPLE FRUIT WITH AND WITHOUT FRUIT THINNING

HortScience ◽  
1994 ◽  
Vol 29 (5) ◽  
pp. 472c-472
Author(s):  
Douglas D. Archbold
Keyword(s):  
Growth Rate ◽  
Dry Weight ◽  
Soluble Starch ◽  
Apple Fruit ◽  
Cultivar Differences ◽  
Storage Carbohydrate ◽  
Allocation Patterns ◽  
Total Dry Weight ◽  
Over Time ◽  
June Drop

Over 4 years, using estimates of fruit dry weight derived from diameter measurements in situ, cultivar variation in apple fruit relative growth rate (RGR) in the period following June drop was evident. These differences diminished as the season progressed however. Using estimates of dry weight per cell, fruit cell absolute growth rate increased over time and RGR showed no clear pattern in contrast to the RGR of whole fruit. There were no cultivar differences in carbohydrate allocation among the soluble, starch, and remaining ethanol-insoluble, non-hydrolyzable pools irrespective of cultivar RGR. The storage carbohydrate pool comprised an increasing fraction of the total dry weight over time with the starch pool comprising 10 to 25% of the storage carbohydrate, varying with season and cultivar. Neither fruit competition within a cluster nor post-June drop thinning altered fruit RGR or carbohydrate allocation patterns when compared to fruit thinned post-bloom.

Introduction History Influences Aboveground Biomass Allocation in Brazilian Peppertree (Schinus terebinthifolius)

2017 ◽  
Vol 10 (3) ◽  
pp. 247-253 ◽  
Author(s):  
Kelley D. Erickson ◽  
Paul D. Pratt ◽  
Min B. Rayamajhi ◽  
Carol C. Horvitz
Keyword(s):  
Biomass Allocation ◽  
Aboveground Biomass ◽  
Dry Weight ◽  
Schinus Terebinthifolius ◽  
Introduction History ◽  
Stem Size ◽  
Dependent Variables ◽  
Number Of Leaves ◽  
Total Dry Weight ◽  
Leaf Dry Weight

Multiple introductions of an exotic species can facilitate invasion success by allowing for a wider range of expressed trait values in the adventive range. Schinus terebinthifolius (Brazilian peppertree) is an invasive shrub that was introduced into Florida in two separate introductions and has subsequently hybridized, resulting in three distinct lineages (eastern, western, and hybrid). To determine whether allocation of aboveground biomass differed by introduction history, we destructively sampled 257 stems from each of six populations with differing introduction histories. The proportion of aboveground biomass allocated to fruit, wood, and leaves differed among the three populations. To determine whether the relationship between stem size and several dependent variables that measure plant performance (total dry weight, wood dry weight, number of fruits, fruit dry weight, leaf dry weight, and number of leaves) differed quantitatively by introduction history, we performed analyses of covariance. Slopes of these relationships (dependent variable vs. stem size) varied by lineage. Hybrid populations had the steepest slopes for one set of dependent variables (total dry weight, wood dry weight, and leaf dry weight), while western populations had the steepest slopes for a different set of dependent variables (number of fruits, fruit dry weight, and number of leaves). The parameterized regression equations for each dependent variable and lineage were used to nondestructively estimate different kinds of production by individuals that are part of long-term longitudinal studies to understand the demographic consequences of these different biomass allocation strategies for the performance of S. terebinthifolius individuals across the invaded range in Florida.

Growth and biomass allocation of Ruppia occidentalis in three lakes, differing in salinity

1985 ◽  
Vol 63 (11) ◽  
pp. 2004-2014 ◽  
Author(s):  
Brian C. Husband ◽  
Michael Hickman
Keyword(s):  
Growth Rate ◽  
Biomass Allocation ◽  
Dry Weight ◽  
Maximum Growth ◽  
Freshwater Lake ◽  
Lake Chemistry ◽  
Shoot Dry Weight ◽  
Wide Range ◽  
Total Dry Weight ◽  
Root:Shoot Ratios

The hypothesis that the growth and distribution of Ruppia occidentalis S. Wats. increases with increasing salinity in Alberta lakes was investigated by comparing populations of Ruppia from three lakes, spanning a wide range of total dissolved solids (0.3–6.2‰). Growth and biomass allocation of individuals were correlated with lake chemistry. Plants from the freshwater lake exhibited characters associated with moderate chemical deficiency, including decreased growth rate, decreased reproductive output, and high root:shoot ratios. The proportion of total dry weight decreased in roots and increased in shoots with salinity but varied little among depths within the lake. Changes in shoot dry weight were the result of vertical growth in the saline lakes but the result of horizontal growth through tiller production in the freshwater lake. Although salinity did not affect the reproductive effort in flowering individuals, the number of flowering individuals in the population increased with salinity. The frequency of occurrence and percentage cover of Ruppia within each lake reflect its respective growth rate and reproduction. The within-lake distributions are characterized by significant interactions between salinity and both depth distribution and substratum type. Saline conditions are required by Ruppia and not merely tolerated for maximum growth and reproduction. Its absence from many freshwater lakes is due most likely to chemical constraints on survival or on the competitive ability of Ruppia.

Above- and below-ground biomass, and allometry, of four common northern Australian mangroves

2005 ◽  
Vol 53 (5) ◽  
pp. 431 ◽  
Author(s):  
B. W. T. Comley ◽  
K. A. McGuinness
Keyword(s):  
Large Scale ◽  
Carbon Allocation ◽  
Dry Weight ◽  
Avicennia Marina ◽  
Abundant Species ◽  
Mangrove Forests ◽  
Rhizophora Stylosa ◽  
Ground Biomass ◽  
Below Ground ◽  
Total Dry Weight

Mangrove forests are an integral part of tropical coastal ecosystems, particularly in northern Australia. In the Northern Territory, studies have determined the extent and species diversity of these associations but little is known of biomass or productivity. We sampled the above- and below-ground biomass of the four most abundant species, Avicennia marina, Bruguiera exaristata, Ceriops australis and Rhizophora stylosa, developed allometric relationships and examined partitioning. Unlike many other studies, we sampled below-ground biomass, which constituted a substantial proportion (0.29–0.57) of the total dry weight. Our results should be valuable in modelling potential changes in carbon allocation resulting from small- and large-scale ecosystem changes.

BIOASSAY OF PROLACTIN

1969 ◽  
Vol 60 (1) ◽  
pp. 91-100 ◽  
Author(s):  
Charles S. Nicoll
Keyword(s):  
Epithelial Cells ◽  
Lipid Content ◽  
Dry Weight ◽  
Fat Content ◽  
Assay Sensitivity ◽  
Mucosal Epithelium ◽  
Wet Weight ◽  
Total Dry Weight

ABSTRACT The response of the pigeon crop-sac to systemically acting prolactin (injected subcutaneously) was evaluated by measuring the wet weight of the responsive lateral lobes of the organ and by determining the dry weight of a 4 cm diameter disc of mucosal epithelium taken from one hemicrop. Of several different injection schedules tested, administration of prolactin in four daily injections was found to yield optimal responses. When compared with a graded series of prolactin doses, measurement of the mucosal dry weight proved to be a better method of response quantification than determination of the crop-sac wet weight with respect to both assay sensitivity and precision. The submucosal tissue of the crop-sac was estimated to constitute about 64 % of the total dry weight of the unstimulated organ and it was found to be relatively unresponsive to prolactin stimulation in comparison with the mucosa. The lipid content of the mucosal epithelium was determined using unstimulated crop-sacs or tissues which showed varying degrees of prolactin-induced proliferation. The fat content of the mucosal epithelial cells increased only slightly more rapidly than the dry weight or the defatted dry weight of the mucosa. Suggestions are made for the further improvement of the systemic crop-sac assay for prolactin.

Adaptation of biomass allocation patterns of wild Fritillaria unibracteata to alpine environ-ment in the eastern Qinghai-Xizang Plateau

2013 ◽  
Vol 37 (3) ◽  
pp. 187-196 ◽  
Author(s):  
Bo XU ◽  
Jin-Niu WANG ◽  
Fu-Sun SHI ◽  
Jing GAO ◽  
Ning WU
Keyword(s):  
Biomass Allocation ◽  
Allocation Patterns ◽  
Xizang Plateau

Impact of an Open Trellis on Canopy Growth, Light Interception, Yield, and Leaf Physiology of Red Raspberry (Rubus idaeus)

HortScience ◽  
1998 ◽  
Vol 33 (3) ◽  
pp. 468b-468
Author(s):  
Stephen F. Klauer ◽  
J. Scott Cameron ◽  
Chuhe Chen
Keyword(s):  
Leaf Area ◽  
Total Nitrogen ◽  
Dry Weight ◽  
Light Interception ◽  
Rubus Idaeus ◽  
Above Ground Biomass ◽  
Red Raspberry ◽  
Leaf Physiology ◽  
Total Dry Weight ◽  
Upper Third

After promising results were obtained with an open-style split trellis (two top wires) in its initial year, two new trials were established in 1997 in northwest (Lynden) and southwest (Woodland) Washington. For the split trellis, actual yields were 33% (machine-picked 1/2 season) and 17% (hand-picked) greater, respectively, for the two locations compared to the conventional trellis (one top wire). In Woodland, canes from the split trellis had 33% more berries, 55% more laterals, 69% more leaves, and 25% greater leaf area compared with the conventional trellis. Greatest enhancement of these components was in the upper third of the canopy. Laterals were also shorter in this area of the split canopy, but there was no difference in average total length of lateral/cane between trellis types. Total dry weight/cane was 22% greater in the split trellis, but component partitioning/cane was consistent between the two systems with fruit + laterals (43%) having the greatest above-ground biomass, followed by the stem (30% to 33%) and the leaves (21% to 22%). Measurement of canopy width, circumference, and light interception showed that the split-trellis canopy filled in more quickly, and was larger from preanthesis through postharvest. Light interception near the top of the split canopy was 30% greater 1 month before harvest with 98% interception near the top and middle of that canopy. There was no difference between the trellis types in leaf CO2 assimilation, spectra, or fluorescence through the fruiting season, or in total nitrogen of postharvest primocane leaves.

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