scholarly journals Growth Respiration, Maintenance Respiration, and Carbon Fixation of Vinca: A Time Series Analysis

2000 ◽  
Vol 125 (6) ◽  
pp. 702-706 ◽  
Author(s):  
Marc W. van Iersel ◽  
Lynne Seymour
Keyword(s):  
Carbon Balance ◽  
Carbon Fixation ◽  
Plant Size ◽  
Carbon Gain ◽  
Maintenance Respiration ◽  
Carbon Use Efficiency ◽  
Size Growth ◽  
Growth Respiration ◽  
Use Efficiency ◽  
Traditional Approaches

Respiration is important in the overall carbon balance of plants, and can be separated into growth (Rg) and maintenance respiration (Rm). Estimation of Rg and Rm throughout plant development is difficult with traditional approaches. Here, we describe a new method to determine ontogenic changes in Rg and Rm. The CO2 exchange rate of groups of 28 `Cooler Peppermint' vinca plants [Catharanthus roseus (L.) G. Don.] was measured at 20 min intervals for 2 weeks. These data were used to calculate daily carbon gain (DCG, a measure of growth rate) and cumulative carbon gain (CCG, a measure of plant size). Growth and maintenance respiration were estimated based on the assumption that they are functions of DCG and CCG, respectively. Results suggested a linear relationship between DCG and Rg. Initially, Rm was three times larger than Rg, but they were similar at the end of the experiment. The decrease in the fraction of total available carbohydrates that was used for Rm resulted in an increase in carbon use efficiency from 0.51 to 0.67 mol·mol-1 during the 2-week period. The glucose requirement of the plants was determined from Rg, DCG, and the carbon fraction of the plant material and estimated to be 1.39 g·g-1, while the maintenance coefficient was estimated to be 0.031 g·g-1·d-1 at the end of the experiment. These results are similar to values reported previously for other species. This suggests that the use of semicontinuous CO2 exchange measurements for estimating Rg and Rm yields reasonable results.

scholarly journals Light Effects on Wax Begonia: Photosynthesis, Growth Respiration, Maintenance Respiration, and Carbon Use Efficiency

2004 ◽  
Vol 129 (3) ◽  
pp. 416-424 ◽  
Author(s):  
Krishna S. Nemali ◽  
M.W. van Iersel
Keyword(s):  
Growth Period ◽  
Dry Weight ◽  
Carbon Gain ◽  
Maintenance Respiration ◽  
Gross Photosynthesis ◽  
Carbon Use Efficiency ◽  
Whole Plant ◽  
Growth Respiration ◽  
Use Efficiency ◽  
Gas Exchange System

The effect of increasing daily light integral (DLI; 5.3, 9.5, 14.4, and 19.4 mol·m-2·d-1) on photosynthesis and respiration of wax begonia (Begonia semperflorens-cultorum Hort.) was examined by measuring CO2 exchange rates (CER) for a period of 25 d in a whole-plant gas exchange system. Although plant growth rate (GR, increase in dry weight per day) increased linearly with increasing DLI, plants grown at low DLI (5.3 or 9.5 mol·m-2·d-1) respired more carbohydrates than were fixed in photosynthesis during the early growth period (13 and 4 d, respectively), resulting in a negative daily carbon gain (DCG) and GR. Carbon use efficiency [CUE, the ratio of carbon incorporated into the plant to C fixed in gross photosynthesis (Pg)] of plants grown at low DLI was low, since these plants used most of the C fixed in Pg for maintenance respiration (Rm), leaving few, if any, C for growth and growth respiration (Rg). Maintenance respiration accounted for a smaller fraction of the total respiration with increasing DLI. In addition, the importance of Rm in the carbon balance of the plants decreased over time, resulting in an increase in CUE. At harvest, crop dry weight (DWCROP) increased linearly with increasing DLI, due to the increased photosynthesis and CUE at high PPF.

scholarly journals Acclimation of Plant Populations to Shade: Photosynthesis, Respiration, and Carbon Use Efficiency

2005 ◽  
Vol 130 (6) ◽  
pp. 918-927 ◽  
Author(s):  
Jonathan M. Frantz ◽  
Bruce Bugbee
Keyword(s):  
Growth Models ◽  
Photon Flux ◽  
Carbon Gain ◽  
Low Light ◽  
Carbon Use Efficiency ◽  
Grand Rapids ◽  
Use Efficiency ◽  
Gas Exchange System ◽  
Photosynthesis And Respiration

Cloudy days cause an abrupt reduction in daily photosynthetic photon flux (PPF), but we have a poor understanding of how plants acclimate to this change. We used a unique 10-chamber, steady-state, gas-exchange system to continuously measure daily photosynthesis and night respiration of populations of a starch accumulator [tomato (Lycopersicon esculentum Mill. cv. Micro-Tina)] and a sucrose accumulator [lettuce (Lactuca sativa L. cv. Grand Rapids)] over 42 days. All measurements were done at elevated CO2 (1200 μmol·mol-1) to avoid any CO2 limitations and included both shoots and roots. We integrated photosynthesis and respiration measurements separately to determine daily net carbon gain and carbon use efficiency (CUE) as the ratio of daily net C gain to total day-time C fixed over the 42-day period. After 16 to 20 days of growth in constant PPF, plants in some chambers were subjected to an abrupt PPF reduction to simulate shade or a series of cloudy days. The immediate effect and the long term acclimation rate were assessed from canopy quantum yield and carbon use efficiency. The effect of shade on carbon use efficiency and acclimation was much slower than predicted by widely used growth models. It took 12 days for tomato populations to recover their original CUE and lettuce CUE never completely acclimated. Tomatoes, the starch accumulator, acclimated to low light more rapidly than lettuce, the sucrose accumulator. Plant growth models should be modified to include the photosynthesis/respiration imbalance and resulting inefficiency of carbon gain associated with changing PPF conditions on cloudy days.

scholarly journals The effect of nutrient availability on global forest carbon balance is uncertain

2014 ◽  
Author(s):  
Enzai Du
Keyword(s):  
Nutrient Availability ◽  
Carbon Balance ◽  
Gross Primary Production ◽  
Sampling Effect ◽  
Significant Control ◽  
Carbon Use Efficiency ◽  
Ecosystem Carbon ◽  
Ecosystem Production ◽  
Use Efficiency ◽  
Uneven Sampling

To the Editor ? Fern?ndez-Mart?nez et al. 1 show a chief determinant of nutrient availability on net ecosystem production (NEP) and ecosystem carbon-use efficiency (CUEe, the ratio of NEP to gross primary production i.e. GPP) in global forests. However, their conclusions depend on an improper treatment of differences in the GPP range of nutrient-rich and nutrient-poor forests (uneven sampling effect) and outliers. A statistical re-analysis of their datasets, while simultaneously excluding the uneven sampling effect and outliers, indicates no significant control of nutrient availability on carbon (C) balance.

scholarly journals Respiratory Q10 of Lettuce Increases with Increasing Plant Size

HortScience ◽  
2004 ◽  
Vol 39 (4) ◽  
pp. 854D-855
Author(s):  
Marc W. van Iersel*
Keyword(s):  
Growth Rate ◽  
Exchange Rate ◽  
Plant Growth ◽  
Plant Size ◽  
Maintenance Respiration ◽  
Relative Growth ◽  
Growth Respiration ◽  
Increasing Temperature ◽  
Growth Respiration Coefficient ◽  
Maintenance Respiration Coefficient

Literature reports on the Q10 for respiration vary widely, both within and among species. Plant size and metabolic activity may be responsible for some of this variation. To test this, respiration of whole lettuce plants was measured at temperatures ranging from 6 to 31 °C during a 24-h period. Subsequently, plant growth rate (in moles of carbon per day) was determined by measuring the CO2 exchange rate of the same plants during a 24-h period. Environmental conditions during this 24-h period resembled those that the plants were exposed to in the greenhouse. The measured growth rate was then used to estimate the relative growth rate (RGR) of the plants. The respiratory Q10 ranged from 1.4 for small plants to 1.75 for large plants. The increase in Q10 with increasing plant size was highly significant, as was the decrease in Q10 with increasing RGR. However, growth rate had little or no effect on the respiratory Q10. One possible explanation for these findings is that the Q10 depends on the ratio of growth to maintenance respiration (which is directly related to RGR). The growth respiration coefficient generally is considered to be temperature-insensitive, while the maintenance respiration coefficient normally increases with increasing temperature. Based on this concept, the Q10 for the maintenance respiration coefficient can be estimated as the estimated Q10 at a RGR of zero (i.e. no growth and thus no growth respiration), which was 1.65 in this experiment. Although the concept of dividing respiration into growth and maintenance fractions remains controversial, it is useful for explaining changes in respiratory Q10 during plant development.

scholarly journals Reply to 'Uncertain effects of nutrient availability on global forest carbon balance' and 'Data quality and the role of nutrients in forest carbon-use efficiency'

2015 ◽  
Vol 5 (11) ◽  
pp. 960-961 ◽  
Author(s):  
M. Fernández-Martínez ◽  
S. Vicca ◽  
I. A. Janssens ◽  
J. Sardans ◽  
S. Luyssaert ◽  
...  
Keyword(s):  
Data Quality ◽  
Nutrient Availability ◽  
Carbon Balance ◽  
Forest Carbon ◽  
Carbon Use Efficiency ◽  
Use Efficiency

scholarly journals A Multiple Chamber, Semicontinuous, Crop Carbon Dioxide Exchange System: Design, Calibration, and Data Interpretation

2000 ◽  
Vol 125 (1) ◽  
pp. 86-92 ◽  
Author(s):  
M.W. van Iersel ◽  
B. Bugbee
Keyword(s):  
Environmental Control ◽  
Dark Respiration ◽  
Net Photosynthesis ◽  
Data Interpretation ◽  
Crop Growth ◽  
Carbon Gain ◽  
Carbon Dioxide Exchange ◽  
Gross Photosynthesis ◽  
Carbon Use Efficiency ◽  
Use Efficiency

Long-term, whole-crop CO2 exchange measurements can be used to study factors affecting crop growth. These factors include daily carbon gain, cumulative carbon gain, and carbon use efficiency, which cannot be determined from short-term measurements. We describe a system that measures semicontinuously crop CO2 exchange in 10 chambers over a period of weeks or months. Exchange of CO2 in every chamber can be measured at 5 min intervals. The system was designed to be placed inside a growth chamber, with additional environmental control provided by the individual gas exchange chambers. The system was calibrated by generating CO2 from NaHCO3 inside the chambers, which indicated that accuracy of the measurements was good (102% and 98% recovery for two separate photosynthesis systems). Since the systems measure net photosynthesis (Pnet, positive) and dark respiration (Rdark, negative), the data can be used to estimate gross photosynthesis, daily carbon gain, cumulative carbon gain, and carbon use efficiency. Continuous whole-crop measurements are a valuable tool that complements leaf photosynthesis measurements. Multiple chambers allow for replication and comparison among several environmental or cultural treatments that may affect crop growth. Example data from a 2 week study with petunia (Petunia ×hybrida Hort. Vilm.-Andr.) are presented to illustrate some of the capabilities of this system.

Sign in / Sign up

Export Citation Format

Share Document