Impact of ozone and sulfur dioxide on net photosynthesis of hybrid poplar cuttings

1984 ◽  
Vol 14 (3) ◽  
pp. 385-388 ◽  
Author(s):  
K. F. Jensen ◽  
R. D. Noble
Keyword(s):  
Respiration Rate ◽  
Hybrid Poplar ◽  
Net Photosynthesis ◽  
Compensation Point ◽  
Visible Injury ◽  
Photosynthetic Rates ◽  
Treatment Groups ◽  
Point Data ◽  
Poplar Cuttings ◽  
Air Control

Softwood cuttings of hybrid poplar clone No. 207 (Populusdeltoides Bartr. × Populustrichocarpa Torry and Gray) were fumigated with either charcoal-filtered air (control), 0.5 ppm SO2, or 0.5 ppm SO2 + 0.25 ppm O3 for 12 h each day for 3 weeks. The net photosynthetic rate and CO2 compensation point were then measured in a closed-loop gas assimilation system with an infrared gas analyzer. Net photosynthesis was measured at light intensities of 430 and 730 μE•m−2•s−1 (photosynthetically active radiation) and in CO2 concentrations of 300, 500, and 1000 ppm. Net photosynthesis increased with an increase in light intensity and CO2 concentration but was significantly reduced by the SO2 + O3 treatment. The leaves were classified into five groups on the basis of visible injury. There were no significant differences in the net photosynthetic rates among uninjured leaves in the three fumigation treatments. However, analysis of the data from the SO2 + O3 treatment, which separated the leaves into injury classes, showed that the CO2 – injury class interaction was significant. At 300 ppm CO2, there were no significant differences in the net photosynthetic rates among the five injury classes. At 500 and 1000 ppm CO2, there were significant differences in the photosynthetic rates between leaves without visible injury and those with injury. Photosynthesis in the injured leaves may have been suppressed by an increase in the respiration rate and a decrease in the photosynthetic area. The increased respiration rate is suggested by the CO2 compensation point data that was significantly higher in all of the fumigated leaves. There were no significant differences in the chlorophyll content of the leaves from the three treatment groups.

scholarly journals Effect of Radiation and Temperature on Cranberry Photosynthesis and Characterization of Diurnal Change in Photosynthesis

2004 ◽  
Vol 129 (1) ◽  
pp. 106-111 ◽  
Author(s):  
S. Kumudini
Keyword(s):  
Net Photosynthesis ◽  
Vaccinium Macrocarpon ◽  
Controlled Environment ◽  
Photosynthetic Response ◽  
Radiation Level ◽  
Photosynthetic Rates ◽  
Air Temperatures ◽  
Predicted Values ◽  
The Impact

Cranberry [Vaccinium macrocarpon (Ait.)] yield has been associated with photosynthate supply. However, the impact of temperature and radiation on photosynthesis of the cranberry plant is not well understood. The objective of this experiment was to characterize the photosynthetic response to radiation and temperature in order to develop a model for estimation of cranberry photosynthetic rates. Two cranberry cultivars, `Stevens' and `Ben Lear', were tested for photosynthetic response at air temperatures ranging from 15 to 35 °C and radiation intensities from 200 to 1200 μmol·m-2·s-1. Depending on temperature, maximum photosynthesis (Pmax) was ≈10 or 12 μmol CO2/m2/s (net photosynthesis) and the saturating radiation level was estimated to be 600 to 800 μmol·m-2·s-1. Cranberry quantum yield was estimated as 0.03 mol CO2/mol photon. Both models; Blackman and the nonrectangular hyperbola with a Θ (angle of curvature) of 0.99 were a good fit for measured photosynthetic rates under controlled environment conditions. The disparity between modeled predicted values, and observed values in the field around midday, indicates a reduction in potential photosynthetic rates in a diurnal cycle that is consistent with the phenomenon of midday depression.

Planting Date Affects Survival and Height Growth of Hybrid Poplar

1986 ◽  
Vol 62 (3) ◽  
pp. 164-169 ◽  
Author(s):  
Edward A. Hansen
Keyword(s):  
Hybrid Poplar ◽  
Late Summer ◽  
Growing Season ◽  
Climatic Conditions ◽  
Planting Date ◽  
Planting Dates ◽  
Soil Frost ◽  
Growing Seasons ◽  
Poplar Cuttings ◽  
Energy Plantations

In this study I investigated the effects of planting date for soaked versus unsoaked cuttings of two hybrid poplar clones under irrigated versus unirrigated and weedy versus weed-free conditions. Cuttings were planted each year for 4 years. Survival at the end of the first growing season was generally greater than 90% for all planting dates. At the end of the second growing season survival for trees planted before July 16 was again generally more than 90%. However, cuttings planted from July 30 through August 27 showed a major decline in survival and survival of fall planted cuttings ranged from 6 to 90%. Mortality of late summer- or fall-planted cuttings occurred prior to the beginning of the second growing season and was attributed to frost heaving. The tallest trees were not those planted at the earliest possible dates (April in Rhinelander). Instead, the tallest trees at the end of the first and second growing seasons were those planted in early- and mid-May. This optimum planting period was the same regardless of clone, soaking, irrigation, or weed treatment. Actual optimum planting date would change with location and local climatic conditions. Some climatic indices may prove more universal in predicting when to plant. Although tentative, it appears that for best growth, unrooted hybrid poplar cuttings should be planted in soil warmer than 10 °C. Trees do not grow as well if planted immediately after soil frost leaves the ground. Key words: Energy plantations, plantation establishment, woody biomass, intensive culture, Populus.

Effects of sulfur dioxide on water relations of hybrid poplar foliage and bark

1982 ◽  
Vol 12 (3) ◽  
pp. 612-616 ◽  
Author(s):  
Alan R. Biggs ◽  
Donald D. Davis
Keyword(s):  
Sulfur Dioxide ◽  
Water Potential ◽  
Water Relations ◽  
Osmotic Potential ◽  
Hybrid Poplar ◽  
Leaf Conductance ◽  
Unexposed Control ◽  
Poplar Cuttings ◽  
Induced Changes

Hybrid poplar cuttings were exposed to 0.25 ppm SO2 for 72 h/week for 14 consecutive weeks in 1979. In 1980, a second set of cuttings was exposed to 0.12 ppm SO2 for 72 h/week for 6 consecutive weeks. Foliar and bark water potential, osmotic potential, and the pressure component, as well as leaf conductance, were determined during or following exposure and compared with data from unexposed control plants. Leaf conductance was stimulated during 72-h exposures to 0.25 ppm SO2. Six 72 h/week exposures to 0.12 ppm SO2 had no effect on conductance, but induced changes in foliar water potential and osmotic potential.

Comparative Net Photosynthesis of Four Hevea brasiliensis Clonal Seedlings

1978 ◽  
Vol 14 (4) ◽  
pp. 337-340 ◽  
Author(s):  
Zahar Samsuddin ◽  
Ivan Impens
Keyword(s):  
Hevea Brasiliensis ◽  
Light Response ◽  
Net Photosynthesis ◽  
Response Curves ◽  
Photosynthetic Rates ◽  
Light Response Curves ◽  
Single Leaf

SUMMARYSingle-leaf net photosynthesis versus light response curves of four Hevea brasiliensis clonal seedlings showed that it was possible to divide photosynthetic rates into high and low classes.

The ecology of Ramalina menziesii. VI. Laboratory responses of net CO2 exchange to moisture, temperature, and light

1987 ◽  
Vol 65 (1) ◽  
pp. 182-191 ◽  
Author(s):  
U. Matthes-Sears ◽  
T. H. Nash III ◽  
D. W. Larson
Keyword(s):  
Dark Respiration ◽  
Net Photosynthesis ◽  
Co2 Exchange ◽  
Response Curves ◽  
Central California ◽  
Photosynthetic Rates ◽  
Chlorophyll Contents ◽  
The Mean ◽  
The Difference ◽  
Thallus Water Content

The response of net CO2 exchange to thallus water content, thallus temperature, and photosynthetically active radiation was measured in the laboratory for two morphologically different forms of Ramalina menziesii collected from a coastal and an inland habitat in central California. Equations describing the response curves are fitted to the data and compared statistically for the two sites during two seasons. Significant differences were present for all responses both in summer and winter but were more pronounced for net photosynthesis than for dark respiration. The main differences between the two forms were in the absolute rates of net photosynthesis; a maximum of 6.2 was measured for the inland form but only 3.6 mg∙g−1∙h−1 for the coastal form. Chlorophyll contents were also different between the two forms, indicating that chlorophyll is the likely cause for the difference in net photosynthetic rates. Net photosynthetic rates were higher at low temperatures during winter than during summer, but otherwise seasonal variations in the gas exchange responses were relatively minor. Both forms of the lichen are light saturated at quantum fluxes greater than 200 μE∙m−2∙s−1. Both show an optimum temperature for maximum CO2 exchange at 25 °C, well above the mean operating temperature of R. menziesii in the field.

scholarly journals Limitations to leaf photosynthesis in field-grown grapevine under drought — metabolic and modelling approaches

2002 ◽  
Vol 29 (4) ◽  
pp. 451 ◽  
Author(s):  
João P. Maroco ◽  
M. Lucília Rodrigues ◽  
Carlos Lopes ◽  
M. Manuela Chaves
Keyword(s):  
Gas Exchange ◽  
Stomatal Closure ◽  
Net Photosynthesis ◽  
Co2 Assimilation ◽  
Quantum Yields ◽  
Vitis Vinifera L ◽  
Lower Efficiency ◽  
Photosynthetic Rates ◽  
Fructose 1,6 Bisphosphate

The effects of a slowly-imposed drought stress on gas-exchange, chlorophyll a fluorescence, biochemical and physiological parameters of Vitis vinifera L. leaves (cv. Aragonez, syn. Tempranillo) growing in a commercial vineyard (South Portugal) were evaluated. Relative to well-watered plants (predawn water potential, ΨPD = –0.13 ± 0.01 MPa), drought-stressed plants (ΨPD = –0.97 ± 0.01 MPa) had lower photosynthetic rates (ca 70%), stomatal conductance, and PSII activity (associated with a higher reduction of the quinone A pool and lower efficiency of PSII open centres). Stomatal limitation to photosynthesis was increased in drought-stressed plants relative to well-watered plants by ca 44%. Modelled responses of net photosynthesis to internal CO2 indicated that drought-stressed plants had significant reductions in maximum Rubisco carboxylation activity (ca 32%), ribulose-1,5-bisphosphate regeneration (ca 27%), and triose phosphate (triose-P) utilization rates (ca 37%) relative to well-watered plants. There was good agreement between the effects of drought on modelled biochemical parameters, and in vitro activities of key enzymes of carbon metabolism, namely Rubisco, glyceraldehyde-3-phosphate dehydrogenase, ribulose-5-phosphate kinase and fructose-1,6-bisphosphate phosphatase. Quantum yields measured under both ambient (35 Pa) and saturating CO2 (100 Pa) for drought-stressed plants were decreased relative to well-watered plants, as well as maximum photosynthetic rates measured at light and CO2 saturating conditions (three times ambient CO2 levels). Although stomatal closure was a strong limitation to CO2 assimilation under drought, comparable reductions in electron transport, CO2 carboxylation, and utilization of triose-P capacities were also adaptations of the photosynthetic machinery to dehydration that slowly developed under field conditions. Results presented in this study confirm that modelling photosynthetic responses based on gas-exchange data can be successfully used to predict metabolic limitations to photosynthesis.

Water relations, photosynthetic capacity, and root/shoot partitioning of photosynthate as determinants of productivity in hybrid poplar

1989 ◽  
Vol 67 (6) ◽  
pp. 1689-1697 ◽  
Author(s):  
T. J. Tschaplinski ◽  
T. J. Blake
Keyword(s):  
Net Photosynthetic Rate ◽  
Biomass Production ◽  
Photosynthetic Rate ◽  
Populus Deltoides ◽  
Hybrid Poplar ◽  
Net Photosynthesis ◽  
Unit Leaf ◽  
Vigorous Growth ◽  
The Difference ◽  
Causal Sequence

Physiological determinants of productivity, including net photosynthesis, root/shoot partitioning of photosynthate, and leaf retention were investigated for three Populus deltoides Bartr. × nigra L. (DN 2, DN 22, DN 15) and two P. balsamifera L. × deltoides Bartr. (Jackii 4, Jackii 7) hybrids. Performance of the different hybrids was compared under controlled greenhouse conditions and in the field. There was a 2.4-fold difference in biomass production between the faster growing DN 2 and the slower growing DN 15 after 100 days growth in the greenhouse, and a 1.5-fold difference after the 1st year's growth in the field. When coppice regrowth of the two Jackii hybrids was compared after 143 days under field conditions, the biomass production of Jackii 4 was 2.2 times that of Jackii 7 and net photosynthetic rate per unit leaf area was 50 % higher than that of Jackii 7 over most of the summer. Many physiological and morphological factors contributed to the more vigorous growth of coppice DN 2 and Jackii 4. These included vigorous initial root growth relative to shoot growth, the ability to maintain higher xylem pressure potentials, net photosynthetic rate, and transpiration rate. These factors may have delayed leaf senescence and late-season photosynthetic decline of older leaves until later in the growing season. The possible causal sequence of physiological events contributing to the difference in productivity and the use of these factors for the early selection of productive hybrids or genotypes are discussed.

scholarly journals Effect of Two Cooling Frequencies on Respiration Rate in Lactating Dairy Cows Under Hot and Humid Climate Conditions

2019 ◽  
Vol 19 (3) ◽  
pp. 821-834 ◽  
Author(s):  
Severino Pinto ◽  
Gundula Hoffmann ◽  
Christian Ammon ◽  
Wolfgang Heuwieser ◽  
Harel Levit ◽  
...  
Keyword(s):  
Dairy Cows ◽  
Respiration Rate ◽  
Coat Color ◽  
Humid Climate ◽  
Related Factors ◽  
Digital Photograph ◽  
Stress Assessment ◽  
Climate Conditions ◽  
Treatment Groups ◽  
Lactating Dairy Cows

AbstractThe aim of this study was to evaluate the effects of evaporative cooling at two different frequencies per day on the respiration rate (RR) of lactating dairy cows, considering cow-related factors. Twenty multiparous Israeli Holstein dairy cows housed in a naturally ventilated cowshed were divided randomly into two treatment groups. The cows of both groups were exposed to 3 or 8 cooling sessions per day (3xcool vs. 8xcool, respectively). The RR was observed hourly, with a maximum of 12 measurements per day. Body posture (standing vs. lying) was simultaneously documented. Milk yield was recorded daily. Coat color was determined from a digital photograph. The RR of standing and lying cows was lower in the 8xcool group (60.2 and 51.6 breaths per min (bpm), respectively) than in the 3xcool group (73.1 and 65.6 bpm, respectively). For each increment of five kilograms of milk produced, RR increased by one bpm, and the RR of cows in early days in milk (DIM) was 12.3 bpm higher than that of cows in late DIM. In conclusion, eight cooling sessions per day instead of three lead to a RR abatement in heat-stressed cows under hot conditions, and cow-related factors directly impact the RR during heat stress assessment.

Sign in / Sign up

Export Citation Format

Share Document