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1.
Root respiration associated with symbiotic fixation in soybean ( Glycine max [L.] Merr.) was estimated by four methods. Averaged over the life of the plant, the root respires 5.8 milligrams C per milligram N accumulated from fixation. When nitrogenase (C2H2) activity and root respiration were decreased by treating roots briefly with 1.0 atmosphere O2, the respiration associated with nitrogenase was estimated as 2.10 micromoles CO2 per micromole C2H4. When nitrogenase activity and respiration were decreased by addition of nitrate, the respiration associated with fixation was calculated as 2.90 micromoles CO2 per micromole C2H4. Removing nodules from roots decreased fixation and root respiration, and the ratio was 4.08 micromoles CO2 per micromole C2H4. When soybean plants were kept in prolonged darkness, then returned to light, the associated drop and recovery of respiration and nitrogenase activity had a ratio of 4.36 micromoles CO2 per micromole C2H2. 相似文献
2.
The rate of dry matter accumulation by seeds of Vicia faba L. cv. Minica increases with temperature in the range of 16 to 26°C. The duration of dry matter accumulation decreases with temperature, resulting in a decrease of final seed dry weight. In this study we test the hypothesis that a diffusion barrier for O 2, located in the seed coat, inhibits seed respiration and growth. The rate of O 2 uptake of intact seeds and of excised embryos and seed coats (separated seeds) was measured in air and buffer at 16, 20, and/or 26°C at various O 2 concentrations and developmental stages. Oxygen uptake rates of intact seeds in buffer were only 9 to 15% of those in air. In buffer, the respiration rate of intact seeds decreased at a pO 2 below air saturation (21 kilopascals), whereas separated seeds showed a decline of O 2 uptake only below 80% of air saturation. In air, embryo excision had no effect on the sensitivity of seed respiration to pO 2, at both 20 and 26°C. In air at 20°C, separated and intact seeds showed similar rates of O 2 uptake. Oxygen uptake by intact seeds, both halfway and beyond the linear growth phase, showed a temperature coefficient Q10 of 2.3 and was insensitive to pO 2 in the range of 80 to 100% of ambient. These results indicate that V. faba seed respiration in air is not limited by the diffusion of O 2 into the seed. 相似文献
3.
The CO 2-exchange rate required to make full use of available N 2-fixation capacity, measured as acetylene reduction, was determined in soybean and alfalfa. Carbohydrates of root systems were depleted during a 40-hour dark treatment; then plants were exposed to a 24-hour light period during which different CO 2-exchange rates were maintained with various CO 2 concentrations. In three- and four-week-old soybeans and four-week-old alfalfa plants, acetylene-reduction capacity was used fully with CO 2-exchange rates as low as 10 milligrams CO 2 per plant per hour. In six-week-old alfalfa plants, however, acetylene reduction rates increased linearly, and apparent N 2-fixation capacity was not used fully when CO 2-exchange rates were higher than 40 milligrams CO 2 per plant per hour. Under the conditions established, the energy cost of N 2 fixation, measured as Δ(respiration of roots + nodules)/Δacetylene reduction over dark-treatment values, was 0.453 milligrams CO 2 per micromole C 2H 4 for all rates of acetylene reduction and for both ages of soybean and alfalfa plants. Thus, root-plus-nodule respiration was not promoted by higher rates of apparent photosynthesis after C 2H 2-reduction capacity became saturated, and all available capacity for apparent N 2 fixation had the same energy requirement. 相似文献
4.
Soybean plants were grown continuously at 350 and 700cm 3m ?3 CO 2 at constant temperature. Respiration rates of third trifoliolate leaves were measured at the growth CO 2 concentration for the whole dark period from 5d before through to 5d after full area expansion. The short-term response of respiration rate to the measurement CO 2 concentration was also determined at each age. Respiration rates per unit of dry mass declined with age and were significantly less at a given age or RGR in leaves grown and measured at the elevated CO 2. The difference in respiration rate was largest in mature leaves and resulted from the different measurement CO 2 concentrations. The respiratory costs of the tissue synthesis, estimated from the elemental composition of the tissue, did not differ substantially between CO 2 treatments. The response of respiration rate to carbon dioxide concentration was not strongly affected by the form of nitrogen supplied. Maintenance respiration calculated by subtracting growth respiration from total respiration was negative in rapidly growing leaves for both CO 2 treatments. This indicates that CO 2 efflux in the dark does not accurately reflect the average 24 h rate of energy expenditure on growth and maintenance for soybean leaves. 相似文献
5.
The linear response of photosynthesis to light at low photon flux densities is known to change abruptly in the vicinity of the light compensation point so that the quantum yield seems to decrease as radiation increases. We studied this `Kok effect' in attached sunflower ( Helianthus annuus L. cv IS894) leaves using gas exchange techniques. The effect was present even though respiration was constant in the dark. It was observed at a similar photon flux density (7 to 11 micromole photons per square meter per second absorbed photosynthetically active radiation) despite a wide range of light compensation points as well as rates of photosynthesis. The effect was not apparent when photorespiration was inhibited at low pO 2 (1 kilopascal), but this result was complicated because dark respiration was quite O 2-sensitive and was partially suppressed under these conditions. The Kok effect was observed at saturating pCO 2 and, therefore, could not be explained by a change in photorespiration. Instead, the magnitude of the effect varied as dark respiration varied in a single leaf, and was minimized when dark respiration was minimized, indicating that a partial suppression of dark respiration by light is responsible. Quantum yields measured at photon flux densities between 0 and 7 to 11 micromole photons per square meter per second, therefore, represent the combined yields of photosynthesis and of the suppression of a component of dark respiration by light. This leads to an overestimate of the quantum yield of photosynthesis. In view of these results, quantum yields of photosynthesis must be measured (a) when respiration is constant in the dark, and (b) when dark respiration has been inhibited either at low pO 2 to eliminate most of the light-induced suppression of dark respiration or at photon flux densities above that required to saturate the light-induced suppression of dark respiration. Significant errors in quantum yields of photosynthesis can result in leaves exhibiting this respiratory behavior if these principles are not followed. 相似文献
6.
Relationships between respiration rate and adenylate and carbohydrate pools of the soybean (Glycine max L. Merrill) fruit during rapid seed growth were evaluated. Plants at mid pod-fill were subjected to different concentrations of CO(2) to alter the amount of photosynthate produced and, thus, available to the fruit. Respiration rate of the intact fruits was measured, along with glucose, sucrose, and starch concentrations, adenylate energy charge (AEC), and total adenylate pool (SigmaAdN) in the pod wall, seed coat, and cotyledons. The concentration of sucrose remained relatively constant in the pod wall (1.0 milligram per 100 milligrams dry weight), seed coat (6.5 milligrams per 100 milligrams dry weight), and cotyledons (4.5 milligrams per 100 milligrams dry weight) at moderate and high respiration rates. Furthermore, AEC remained relatively constant in the pod wall (0.55), seed coat (0.24), and cotyledons (0.44) during changes in respiration rate. This suggests that the amount of assimilate transported to the fruit, and its flux through the sucrose pools of the fruit parts, were important in the regulation of the respiration rate of the fruit. The average SigmaAdN in the seed coat (1300 picomoles per milligram dry weight) was significantly greater than in the cotyledons (750 picomoles per milligram dry weight) and pod wall (300 picomoles per milligram dry weight). In addition, the SigmaAdN in the seed coat and cotyledons increased with increasing respiration rate of the fruit. The high SigmaAdN in the seed coat and its increase with increases in respiration rate of the fruit suggest that an energy-requiring process is involved in the movement of sucrose through the seed coat. 相似文献
7.
Chlamydomonas in the resting phase of growth has an equal capacity of about 15 micromole O 2 uptake per hour per milligram of chlorophyll for both the cytochrome c, CN-sensitive respiration, and for the alternative, salicylhydroxamic acid-sensitive respiration. Alternative respiration capacity was measured as salicylhydroxamic acid inhibited O 2 uptake in the presence of CN, and cytochrome c respiration capacity as CN inhibition of O 2 uptake in the presence of salicylhydroxamic acid. Measured total respiration was considerably less than the combined capacities for respiration. During the log phase of growth on high (2-5%) CO 2, the alternative respiration capacity decreased about 90% but returned as the culture entered the lag phase. When the alternative oxidase capacity was low, addition of salicylic acid or cyanide induced its reappearance. When cells were grown on low (air-level) CO 2, which induced a CO 2 concentrating mechanism, the alternative oxidase capacity did not decrease during the growth phase. Attempts to measure in vivo distribution of respiration between the two pathways with either CN or salicylhydroxamic acid alone were inconclusive. 相似文献
8.
Low phosphate nutrition results in increased chlorophyll fluorescence, reduced photosynthetic rate, accumulation of starch and sucrose in leaves, and low crop yields. This study investigated physiological responses of soybean ( Glycine max [L.] Merr.) leaves to low inorganic phosphate (Pi) conditions. Responses of photosynthesis to light and CO 2 were examined for leaves of soybean grown at high (0.50 millimolar) or low (0.05 millimolar) Pi. Leaves of low Pi plants exhibited paraheliotropic orientation on bright sunny days rather than the normal diaheliotropic orientation exhibited by leaves of high Pi soybeans. Leaves of plants grown at high Pi had significantly higher light saturation points (1000 versus 630 micromole photons [400-700 nanometers] per square meter per second) and higher apparent quantum efficiency (0.062 versus 0.044 mole CO 2 per mole photons) at ambient (34 pascals) CO 2 than did low Pi leaves, yet stomatal conductances were similar. High Pi leaves also had significantly higher carboxylation efficiency (2.90 versus 0.49 micromole CO 2 per square meter per second per pascal), a lower CO 2 compensation point (6.9 versus 11.9 pascals), and a higher photosynthetic rate at 34 pascals CO 2 (19.5 versus 6.7 micromoles CO 2 per square meter per second) than did low Pi leaves. Soluble protein (0.94 versus 0.73 milligram per square centimeter), ribulose-1,5-bisphosphate carboxylase/oxygenase content (0.33 versus 0.25 milligram per square centimeter), and ribulose-1,5-bisphosphate carboxylase/oxygenase specific activity (25.0 versus 16.7 micromoles per square meter per second) were significantly greater in leaves of plants in the high Pi treatment. The data indicate that Pi stress alters the plant's CO 2 reduction characteristics, which may in turn affect the plant's capacity to accommodate normal radiation loads. 相似文献
9.
This investigation presents metabolic evidence to show that in 4- to 5-day-old roots of maize ( Zea mays hybrid GH 5010) exposed to low external O 2 concentrations, the stele receives inadequate O 2 for oxidative phosphorylation, while the cortex continues to respire even when the external solution is at zero O 2 and the roots rely solely on aerenchyma for O 2 transport. Oxygen uptake rates (micromoles per cubic centimeter per hour) declined at higher external O 2 concentrations in excised segments from whole roots than from the isolated cortex; critical O 2 pressures for respiration were greater than 0.26 moles per cubic meter O 2 (aerated solution) for the whole root and only 0.075 moles per cubic meter O 2 for the cortex. For plants with their shoots excised and the cut stem in air, ethanol concentrations (moles per cubic meter) in roots exposed to 0.06 moles per cubic meter O 2 were 3.3 times higher in the stele than in the cortex, whereas this ethanol gradient across the root was not evident in roots exposed to 0 moles per cubic meter O 2. Alanine concentrations (moles per cubic meter) in the stele of roots exposed to 0.13 and 0.09 moles per cubic meter O 2 increased by 26 and 44%, respectively, above the levels found for aerated roots, whereas alanine in the cortex was unchanged; the increase in stelar alanine concentration was not accompanied by changes in the concentration of free amino acids other than alanine. For plants with their shoots intact, alcohol dehydrogenase and pyruvate decarboxylase activities (micromoles per gram protein per minute) in roots exposed to 0.13 moles per cubic meter O 2 increased in the stele by 40 to 50% over the activity in aerated roots, whereas there was no appreciable increase in alcohol dehydrogenase and pyruvate decarboxylase activity in the cortex of these roots. More convincingly, for roots receiving O 2 solely from the shoots via the aerenchyma, pyruvate decarboxylase in the cortex was in an “inactive” state, whereas pyruvate decarboxylase in the stele was in an “active” state. These results suggest that for roots in O 2-free solutions, the aerenchyma provides adequate O 2 for respiration in the cortex but not in the stele, and this was supported by a change in pyruvate decarboxylase in the cortex to an active state when the O 2 supply to the roots via the aerenchyma was blocked. 相似文献
10.
The role of acclimation of dark respiration to temperature and CO 2 concentration and its relationship to growth are critical in determining plant response to predicted global change. We explored temperature acclimation of respiration in seedlings of tree species of the North American boreal forest. Populus tremuloides, Betula papyrifera, Larix laricina, Pinus banksiana, and Picea mariana plants were grown from seed in controlled-environments at current and elevated concentrations of CO 2 (370 and 580 μmol mol –1) in combination with three temperature treatments of 18/12, 24/18, and 30/24 °C (light/dark period). Specific respiration rates of roots and shoots acclimated to temperature, damping increases in rates across growth-temperature environments compared to short-term temperature responses. Compared at a standard temperature, root and shoot respiration rates were, on average, 40% lower in plants grown at the highest compared to lowest growth temperature. Broad-leaved species had a lower degree of temperature acclimation of respiration than did the conifers. Among species and treatment combinations, rates of respiration were linearly related to size and relative growth rate, and relationships were comparable among growth environments. Specific respiration rates and whole-plant respiratory CO 2 efflux as a proportion of daily net CO 2 uptake increased at higher growth temperatures, but were minimally affected by CO 2 concentration. Whole-plant specific respiration rates were two to three times higher in broad-leaved than coniferous species. However, compared to faster-growing broad-leaved species, slower-growing conifers lost a larger proportion of net daily CO 2 uptake as respiratory CO 2 efflux, especially in roots. Interspecific variation in acclimation responses of dark respiration to temperature is more important than acclimation of respiration to CO 2 enrichment in modifying tree seedling growth responses to projected increases in CO 2 concentration and temperature. 相似文献
11.
Mungbean ( Phaseolus aureus Roxb.) seedlings were grown hypobarically to assess the effects of low pressure (21-24 kilopascals) on growth and mitochondrial respiration. Control seedlings grown at ambient pressure (101 kilopascals) were provided amounts of O 2 equivalent to those provided experimental seedlings at reduced pressure to factor out responses to O 2 concentration and to total pressure. Respiration was assayed using washed mitochondria, and was found to respond only to O 2 concentration. Regardless of total pressure, seedlings grown at 2 millimoles O 2 per liter had higher state 3 respiration rates and decreased percentages of alternative respiration compared to ambient (8.4 millimoles O 2 per liter) controls. In contrast, seedling growth responded to total pressure but not to O 2 concentration. Seedlings were significantly larger when grown under low pressure. While low O 2 (2 millimoles O 2 per liter) diminished growth at ambient pressure, growth at low pressure in the same oxygen concentration was enhanced. Respiratory development and growth of mungbean seedlings under low pressure is unimpaired whether oxygen or air is used as the chamber gas, and further, low pressure can improve growth under conditions of poor aeration. 相似文献
12.
To obtain more knowledge about carbon requirements for growth by sponges, the growth rate, respiration rate, and clearance
rate was measured in situ in Haliclona oculata. We found that only 34% of the particulate carbon pumped through the sponge was used for both respiration and growth. The
net growth efficiency, being the ratio of carbon incorporated in biomass and the total carbon used by the sponge for respiration
and growth, was found to be 0.099 ± 0.013. Thus, about 10% of the total used carbon was fixed in biomass, and over 90% was
used for generating energy for growth, maintenance, reproduction, and pumping. H. oculata had 2.5 μmol C available for every micromole O 2 consumed. A value of 0.75 for respiratory quotient (RQ in micromole CO 2 micromole O 2−1) was used for H. oculata, which is the average value reported in literature for different marine invertebrates. Thus, carbon was available
in excess to meet the respiratory demand. Oxygen was found not to be the limiting factor for growth, since only 3.3% of the
oxygen pumped through the sponge body was used. Our results indicate that both oxygen and carbon availability are not limiting.
The low growth efficiency agrees with the low growth rates found for the species used in this study. 相似文献
13.
1H magnetic resonance microtomography imaging was applied to study vascular systems in developing bean ( Phaseolus limensis L.) seeds. Using the gradient echo method, we recorded 2D tomographic sections in the sagittal and axial planes of the fruits
sampled from a vegetating plant on days 10, 17, 24, and 31 after fertilization. Any vascular connection between the tissues
of maternal plant (bean pod and seed coat) and the embryo were undetectable. The embryo has an autonomous branched network
of procambial strands in the cotyledons, converging to the embryonic axis. The bean pods are covered with a network of vascular
bundles; large vascular strands run along the dorsal and ventral sutures. The seed coat vascular bundles are formed in the
process of seed ripening and are represented by a developed vascular system multiply branching in the middle part of the ground
parenchyma at the stage of physiological maturity. They are connected with the source of assimilates via the lateral pod veins
and a large vascular bundle, entering the seed below the hilum via the placenta. Assimilates enter the external part of the
seed coat, which contains no vascular bundles, via the funiculus vascular bundles and hilum tissue. 相似文献
14.
The rates of dark respiration of Glycine max leaves, pods, andseeds, are shown to be positively related to O 2 concentration([O 2]) between 2 and 21 per cent. It is suggested that the reporteddepression of seed growth, due to subatmospheric concentrationsof O 2 is caused simply by depression of respiration and thatit is not necessary to postulate a new control mechanism mediatedby [O 2]. 相似文献
15.
Respiration (carbon efflux) by terrestrial ecosystems is a major component of the global carbon (C) cycle, but the response of C efflux to atmospheric CO 2 enrichment remains uncertain. Respiration may respond directly to an increase in the availability of C substrates at high CO 2, but also may be affected indirectly by a CO 2‐mediated alteration in the amount by which respiration changes per unit of change in temperature or C uptake (sensitivity of respiration to temperature or C uptake). We measured CO 2 fluxes continuously during the final 2 years of a 4‐year experiment on C 3/C 4 grassland that was exposed to a 200–560 μmol mol ?1 CO 2 gradient. Flux measurements were used to determine whether CO 2 treatment affected nighttime respiration rates and the response of ecosystem respiration to seasonal changes in net C uptake and air temperature. Increasing CO 2 from subambient to elevated concentrations stimulated grassland respiration at night by increasing the net amount of C fixed during daylight and by increasing either the sensitivity of C efflux to daily changes in C fixation or the respiration rate in the absence of C uptake (basal ecosystem respiration rate). These latter two changes contributed to a 30–47% increase in the ratio of nighttime respiration to daytime net C influx as CO 2 increased from subamient to elevated concentrations. Daily changes in net C uptake were highly correlated with variation in temperature, meaning that the shared contribution of C uptake and temperature in explaining variance in respiration rates was large. Statistically controlling for collinearity between temperature and C uptake reduced the effect of a given change in C influx on respiration. Conversely, CO 2 treatment did not affect the response of grassland respiration to seasonal variation in temperature. Elevating CO 2 concentration increased grassland respiration rates by increasing both net C input and respiration per unit of C input. A better understanding of how C efflux varies with substrate supply thus may be required to accurately assess the C balance of terrestrial ecosystems. 相似文献
16.
The effect of O 2 partial pressure on the germination and the respiration of 12 cultivated species was studied. The reciprocal of the time necessary to observe rootlet emergence in 50% of the seeds was used to approach the germination rate. The maximum germination and respiration rates were reached in most seeds at O 2 pressures close to that of air. Decreasing the O 2 pressure produced a gradual decrease of the germination rate. The seeds could be classed in two groups according to their response to low O 2 pressures. Group I includes lettuce, sunflower, radish, turnip, cabbage, flax, and soybean: at O 2 pressures close to 2 kilopascals, the germination in this group was stopped and the adenylate energy charge was lower than 0.6. Group II includes rice, wheat, maize, sorghum, and pea. The germination rate of these seeds was also gradually decreased by lowering the O 2 partial pressure but germination still occured, very slowly, at 0.1 kilopascal; the adenylate energy charge remained higher than 0.6. These differences in the germination rates and adenylate energy charge values could not be explained by differences in the sensitivity of respiration to O 2. 相似文献
17.
Oxygenated soybean leghemoglobin and sperm whale myoglobin have been used as sources of O 2 for respiring bacteria in experiments with no gas phase. These O 2-carrying hemoproteins provide dispersed free O 2 at concentrations defined by the kinetic constants of their oxygenation and deoxygenation, and their optical absorption spectra indicate the average concentration of free O 2. They can thus be used to study relationships between concentrations of free O 2, rates of respiration, and other metabolic processes in bacteria suspended in solutions of them. Three types of apparatus are described and examples of studies of respiration and nitrogen fixation by Rhizobium spp. are given. 相似文献
18.
Growth at an elevated CO 2 concentration resulted in an enhanced capacity for soybean ( Glycine max L. Merr. cv Bragg) leaflet photosynthesis. Plants were grown from seed in outdoor controlled-environment chambers under natural solar irradiance. Photosynthetic rates, measured during the seed filling stage, were up to 150% greater with leaflets grown at 660 compared to 330 microliters of CO 2 per liter when measured across a range of intercellular CO 2 concentrations and irradiance. Soybean plants grown at elevated CO 2 concentrations had heavier pod weights per plant, 44% heavier with 660 compared to 330 microliters of CO 2 per liter grown plants, and also greater specific leaf weights. Ribulose 1,5-bisphosphate carboxylase/oxygenase (rubisco) activity showed no response (mean activity of 96 micromoles of CO 2 per square meter per second expressed on a leaflet area basis) to short-term (~1 hour) exposures to a range of CO 2 concentrations (110-880 microliters per liter), nor was a response of activity (mean activity of 1.01 micromoles of CO 2 per minute per milligram of protein) to growth CO 2 concentration (160-990 microliters per liter) observed. The amount of rubisco protein was constant, as growth CO 2 concentration was varied, and averaged 55% of the total leaflet soluble protein. Although CO 2 is required for activation of rubisco, results indicated that within the range of CO 2 concentrations used (110-990 microliters per liter), rubisco activity in soybean leaflets, in the light, was not regulated by CO 2. 相似文献
19.
Isolated soybean ( Glycine max [L.] Merr. cv Wilkin) bacteroids have O 2-dependent nitrogenase activity which is strongly inhibited by supraoptimal O 2 concentrations. Oxygen-inhibited nitrogenase activity is recovered by addition of 10 millimolar sodium succinate or by lowering the O 2 concentration. Brief treatment of roots of intact soybean plants with 1.0 atmosphere O2 reduces nitrogenase activity (C2H2). There is a rapid partial recovery of activity within 2 to 3 hours, and a slower return to near normal levels by 36 hours. The drop and recovery of nitrogenase activity is accompanied by a parallel drop and increase in root respiration. There is a direct relationship between the change in respiration and the change in acetylene reduction following O2 treatment. The O2-mediated changes in nitrogenase activity and root respiration are not affected by the planting medium. The ratio of the change in respiration to the change in nitrogenase activity was the same in 13 soybean cultivars. 相似文献
20.
Summary A simulation model is presented for the distribution and consumption of O 2 in infected cells of soybean root nodule central tissue. It differs from earlier models in closer adherence to observed structure and embodies new morphometric data about the distribution of > 12,000 mitochondria per cell and about the geometry of the gas-filled intercellular spaces near which the mitochondria are located. The model cell is a rhombic dodecahedron and O 2 enters only through interfaces (totalling 26% of the cell surface) with 24 gas-filled intercellular spaces. These spaces are located at the edges of each rhombic face of the cell, forming an interconnected network over the cell suface. Next, O 2 is distributed through the cytoplasm by a leghaemoglobin-facilitated diffusive process, initially between the mitochondria and amyloplasts in the outer layers of the cell and then between > 6,000 symbiosomes (each containing 6 bacteroids) towards the central nucleus. The symbiosomes and mitochondria consume O 2, but impede its diffusion; all O 2 entering symbiosomes is considered to be consumed there. For the calculations, the cell is considered to consist of 24 structural units, each beneath one of the intercellular spaces, and each is divided into 126 layers, 0.2 m thick, in and through which O 2 is consumed and diffused. Rates of consumption of O 2 and of N 2 fixation in each diffusion layer were calculated from previously-established kinetics of respiration by mitochondria and bacteroids isolated from soybean nodules and from established relationships between bacteroid respiration and N 2 fixation. The effects of varying the O 2-supply concentration and the concentration and type of energy-yielding substrates were included in the simulations. When the model cell was supplied with 0.5 mM malate, mitochondria accounted for a minimum of 50% of the respiration of the model cell and this percentage increased with increased concentration of the O 2 supply. Gradients of concentrations of free O 2 dissolved in the cytoplasm were steepest near the cell surface and in this location respiration by mitochondria appeared to exert a marked protective effect for nitrogen fixation in layers deeper within the cell. Estimates of N 2 fixation per nodule, calculated from the model cell, were similar to those calculated from field measurements.Abbreviations Lb
leghaemoglobin
- LbO 2
oxyleghaemoglobin
- [O 2]
concentration of free, dissolved O 2
- e.m.
electron micrograph
Dedicated to the memory of Professor John G. Torrey 相似文献
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