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Oryza sativa; water stress; adverse effects; drought; Klebsiella; nitrogen-fixing bacteria; foliar spraying; plant growth substances; nitrogen fertilizers; nutrient uptake; photosynthesis; carbon dioxide; gas exchange; nutrient content; proline; chemical constituents of plants
Abstract:
... Some of the measures suggested for amelioration of drought effects include application of N fertilizer and plant growth regulators (PGRs). Since N2-fixing bacteria produce plant growth substances (PGRs), the effect of foliar application of an active strain of Klebsiella sp. (KUPOS) on IR-50 rice was examined using three foliar sprays applied at 10-day intervals. Irrigation once every 3 days was es ...
... The NH3 compensation point NH3 compensation point in Hordeum vulgare cvs Golf and Laevigatum was determined at different growth stages under controlled environmental conditions. The plants were grown to maturity in hydroponics under N limitation. When plants were exposed to NH3 at realistic ambient levels ranging from 0 to 25 nmol NH3 mol-1 air at an air temperature of 20 degrees C, a significant ...
... NH3 exchange between oilseed rape (Brassica napus) plants and the atmosphere was examined at realistic ambient NH3 levels under controlled environmental conditions. Different leaf conductances to NH3 diffusion were obtained by changing leaf temperature (10 to 40 degrees C), light intensity (0 to 600 micromoles m-2 s-1), and air humidity (20 to 80%), respectively. NH3 adsorption to the cuticle with ...
... Our previous paper showed that cultivar difference of flag leaf photosynthesis (LPS) in rice (Oryza sativa L.) was attributed to the difference in mesophyll resistance (rm). In this paper, we tried to divide rm into CO2 transfer resistance (rr) and CO2 fixation resistance (rc) for further analysis of rm by means of delta 13C determination of photosynthetic products. In the heading time, rr, and rc ...
... A numerical model is introduced that solves the steady‐state diffusion equation for a single stoma and the mesophyll surrounding. This system has cylindrical symmetry, and diffusive transport of carbon dioxide in the gas phase is coupled with transfer in mesophyll alone with y photosynthetic sink rate and respiratory production rates. The mesophyll is treated as a continuously distributed liquid p ...
quantitative analysis; thylakoids; Oryza sativa; seedlings; absorption; strain differences; gas exchange; fluorescence; light intensity; light harvesting complex; photosystem II; electron transfer; mutants; photosystem I; chemical constituents of plants; chlorophyll; oxygen
Abstract:
... Light-harvesting capacities of photosystem I (PSI) and photosystem II (PSII) in a wild-type and three chlorophyll b-deficient mutant strains of rice were determined by measuring the initial slope of light-response curve of PSI and PSII electron transport and kinetics of light-induced redox changes of P-700 and Q(A), respectively. The light-harvesting capacity of PSI determined by the two methods w ...
Erythrina poeppigiana; canopy; diameter; height; leaf area; photosynthesis; carbon dioxide; gas exchange; carbon; nutrient balance; pruning; regrowth; solar radiation; light intensity; air temperature; developmental stages; net assimilation rate; diurnal variation; agroforestry; simulation models; biomass production; Costa Rica
Abstract:
... We developed a whole-canopy CO2 exchange simulation model to study effects of pruning on the carbon balance of trees. Model inputs include global short-wave radiation, photosynthetic photon flux density (PFD), air temperature, time series of the development of canopy diameter, height and total leaf area during the simulation period and local geographical and atmospheric parameters. Canopy structur ...
Triticum aestivum; cultivars; water use efficiency; photosynthesis; gas exchange; carbon dioxide; transpiration; leaf area; nutrition-genotype interaction; nitrogen content; leaves; roots; nutrient uptake; nitrogen metabolism; nutrient use efficiency
Abstract:
... We investigated physiological and morphological traits underlying variation in relative growth rate (RGR) among wheat cultivars. Subsequently, we determined whether higher RGR is correlated with higher water demand and lower plant water use efficiency (WUEp). Further, the correlation between water use efficiency and leaf nitrogen concentration was examined. For this purpose we chose four cultivars ...
mathematical models; canopy; water use efficiency; gas exchange; stress response; net assimilation rate; water stress; sap flow; carbon; seasonal variation; leaves; rain; soil water; photosynthesis; Quercus agrifolia; leaf conductance; California
Abstract:
... Quercus agrifolia Nee and Quercus durata Jeps. are sclerophyllous evergreens that co-occur in regions of northern California that have a serpentine-derived soil. The species are of similar stature and density where they grow together, even though late-drought xylem pressure potentials indicate that Q. durata has access to more soil water than Q. agrifolia. To assess how carbon uptake and water-use ...
lichens; carbonate dehydratase; enzyme activity; enzyme inhibitors; gas exchange; light; carbon dioxide; oxygen; photosynthesis; time series analysis
Abstract:
... The activity of the enzyme carbonic anhydrase (CA; E.C. 4.2.1.1) was examined in eight species of lichen in vivo by measurements of ¹⁸O exchange from doubly labelled CO₂ (¹³C¹⁸O¹⁸O) to water, with the aim of determining whether this enzyme is present in lichens and if so to what extent it participates in physiological processes. The lichens were chosen to represent different mycobiont (Heterodera, ...
Rhododendron; stomatal conductance; Stephanitis pyrioides; gas exchange; gender differences; feeding behavior; chlorosis; chemical constituents of plants; photosynthesis; chlorophyll; leaves
Abstract:
... Feeding injury caused by nymphs, males and females of the azalea lace bug, Stephanitis pyrioides (Scott), reduced rates of photosynthesis and transpiration in 'Delaware Valley White' azalea, Rhododendron mucronatum leaves. Females caused substantially more leaf feeding injury than males or nymphs. S. pyrioides was observed to insert stylets through stomata on the lower leaf surface and to feed alm ...
... The physiology and growth of Lygeum spartum and Stipa tenacissima, two perennial tussock grasses which dominate wide areas of semi-arid south-eastern Spain, were compared at times of high and low availability of water, in autumn and summer respectively, to study the adaptation of this growth form to arid environments. The two species differed in morphological and physiological traits. Stipa tussoc ...
canopy; gas exchange; stress response; net assimilation rate; drought; diurnal variation; stomata; wet season; leaf conductance; Malaysia
Abstract:
... Dryobalanops aromatica Gaertn. f. is a major tropical canopy species in lowland tropical rain forests in Peninsular Malaysia. Diurnal changes in net photosynthetic rate (A) and stomatal conductance to water vapor (gs) were measured in fully expanded young and old leaves in the uppermost canopy (35 m above ground). Maximum A was 12 and 10 micromoles m-2 s-1 in young and old leaves, respectively: ho ...