Consulta: subjectFacets:"Net photosynthesis"
Registros recuperados: 7
Data/hora: 13/06/2024 08:26:38

Gas exchange rates, plant height, yield components, and productivity of upland rice as affected by plant regulators
Provedor de dados: 86
Autores: Alvarez,Rita de Cássia Félix; Crusciol,Carlos Alexandre Costa; Nascente,Adriano Stephan; Rodrigues,João Domingos; Habermann,Gustavo.
The objective of this work was to evaluate gas exchange rates, plant height, yield components, and productivity of upland rice, as affected by type and application time of plant growth regulators. A randomized block design, in a 4x2 factorial arrangement, with four replicates was used. Treatments consisted of three growth regulators (mepiquat chloride, trinexapac-ethyl, and paclobutrazol), besides a control treatment applied at two different phenological stages: early tillering or panicle primordial differentiation. The experiment was performed under sprinkler-irrigated field conditions. Net CO2 assimilation, stomatal conductance, plant transpiration, and water-use efficiency were measured four times in Primavera upland rice cultivar, between booting and...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Oryza sativa; Net photosynthesis; Stomatal conductance; Transpiration; Water-use efficiency.
Ano: 2012
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-204X2012001000007

Effects of iron-ore particles on propagule release, growth and photosynthetic performance of Sargassum vulgare C. Agardh (Phaeophyta, Fucales)
Provedor de dados: 88
Autores: NASSAR,CRISTINA A.G.; LAVRADO,HELENA P.; YONESHIGUE-VALENTIN,YOCIE.
The effect of iron-ore particles on the propagule release and growth of Sargassum vulgare C. Agardh was tested under treatments with different concentrations of iron-ore particles: 0.1, 1.0, 10.0 g.L-1 and a solution of 10.0 g.L-1 of filtered iron-ore. Filtered seawater was used as control. Photosynthesis vs. irradiance (P-I) curves were calculated for S. vulgare in the presence of iron-ore and in seawater. There was no significant difference in the number of propagules released by the receptacles or in the percentage of zygote formation among the treatments. The released propagules acted like aggregation centers for the particles, those more heavily coated with iron (10.0 g.L-1) exhibiting the highest sinking velocity (32.6 ± 9.8 mm.s-1). No difference in...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Growth; Iron-ore; Macroalgae; Net photosynthesis; Sargassum vulgare.
Ano: 2002
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-84042002012000010

Photosynthetic performance of Colobanthus quitensis (Kunth) Bartl. (Caryophyllaceae) in a high-elevation site of the Andes of central Chile
Provedor de dados: 97
Autores: CASANOVA-KATNY,M. ANGÉLICA; BRAVO,LEÓN A; MOLINA-MONTENEGRO,MARCO; CORCUERA,LUIS J; CAVIERES,LOHENGRIN A.
Photosynthesis of Colobanthus quitensis and mesoclimatic conditions of air temperature and light intensity during the growing season were investigated at 2,650 m in the central Chilean Andes. On three typical days of the growing period (January, March and May), CO2 exchange and chlorophyll fluorescence were measured. In addition, a series of fluorescence response curves with increasing light intensity at different temperatures were performed to estimate the propensity of Andean C. quitensis populations to be photoinhibited. Net Photosynthesis (Pn) was low (ca. 2.0 mmol CO2 m-2s-1) during the morning and noon in days with high photosynthetic active radiation (PAR, above 1,800 mmol photons m-2s-1). Pn increased in the afternoon (3.5-4.8 mmol CO2 m-2s-1) when...
Tipo: Journal article
Palavras-chave: Net photosynthesis; Chlorophyll fluorescence; NPQ; Alpine climate; Alpine plants; Andes.
Ano: 2006
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0716-078X2006000100004

Leaf gas exchange and yield of three upland rice cultivars
Provedor de dados: 53
Autores: Alvarez,Rita de Cássia Félix; Habermann,Gustavo; Crusciol,Carlos Alexandre Costa; Nascente,Adriano Stephan; Rodrigues,João Domingos.
Studies of physiological parameters associated with crop performance and growth in different groups of upland rice (Oryza sativa L.) may support plant breeding programs. We evaluated the role of gas exchange rates and dry matter accumulation (DMA) as traits responsible for yields in a traditional (cv. ‘Caiapó’), intermediate (cv. ‘Primavera’) and modern (cv. ‘Maravilha’) upland rice cultivars. Leaf gas exchange rates, DMA, leaf area index (LAI), harvest indexes (HI) and yield components were measured on these genotypes in the field, under sprinkler irrigation. Panicles per m2 and DMA at flowering (FL) and heading, as well as CO2 assimilation rates (A) were similar across these cultivars. The highest yield was found in ‘Primavera’, which may be explained by...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Oryza sativa; Net photosynthesis; Harvest index; Dry matter accumulation rates; Crop growth rate.
Ano: 2015
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0006-87052015000100001

Ecophysiology of coconut palm under water stress
Provedor de dados: 61
Autores: Gomes,Fábio P.; Prado,Carlos H.B.A.
Coconut palm is of great social and economic importance for millions of people in the tropics and subtropics. Drought is one of the main environmental factors that limit coconut productivity. In this review, physiological and morphological data are presented in an integrated perspective to provide a holistic view of the behavior of coconut trees facing water deficit under both field and controlled conditions. Great capacity to produce homorhizic roots capable of searching continuously for water and nutrients and high protoplasmic tolerance in leaves allows the coconut tree to endure water deficit. High membrane stability, osmoprotection, osmoregulation and enhanced activity of antioxidant enzymes are characteristics often found in leaves of...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Cocus nucifera; Desiccation tolerance; Leaf gas exchange; Leaf water relations; Net photosynthesis; Osmotic potential; Water potential; Water-use efficiency.
Ano: 2007
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1677-04202007000400008

I. Heat stress in Triticum: kinetics of Ca and Mg accumulation
Provedor de dados: 61
Autores: Dias,Ana S.; Lidon,Fernando C.; Ramalho,José C.
In heat stressed genotypes of Triticum aestivum L. (Sever and Golia) and Triticum turgidum subsp. durum (Acalou and TE 9306), chosen according to its genetic background diversity, Ca and Mg accumulations were correlated with its photosynthetic performance. It was found that with high temperatures the concentrations of Ca increased in the shoots, whereas the accumulation of Mg augmented only in bread wheat genotypes. Under heat stress, the pattern of electrolytes release in Golia and Acalou remained similar, but the extrusion rates became higher in Sever. During grain filling, the levels of total chlorophylls decreased in the heat stressed genotypes (excepting in Sever). In all the Triticum genotypes, stomatal conductance and the net carboxilation rate...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Triticum aestivum L.; Triticum turgidum subsp. durum; Net photosynthesis; Nutrients uptake and translocation; Stomatal conductance.
Ano: 2009
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1677-04202009000200005

Effect of Injecting Hydrogen Peroxide into Heavy Clay Loam Soil on Plant Water Status, NET CO2 Assimilation, Biomass, and Vascular Anatomy of Avocado Trees
Provedor de dados: 117
Autores: Gil M,Pilar M; Ferreyra E,Raúl; Barrera M,Cristián; Zúñiga E,Carlos; Gurovich R,Luis.
In Chile, avocado (Persea americana Mill.) orchards are often located in poorly drained, low-oxygen soils, situation which limits fruit production and quality. The objective of this study was to evaluate the effect of injecting soil with hydrogen peroxide (H2O2) as a source of molecular oxygen, on plant water status, net CO2 assimilation, biomass and anatomy of avocado trees set in clay loam soil with water content maintained at field capacity. Three-year-old ‘Hass’ avocado trees were planted outdoors in containers filled with heavy loam clay soil with moisture content sustained at field capacity. Plants were divided into two treatments, (a) H2O2 injected into the soil through subsurface drip irrigation and (b) soil with no H2O2 added (control). Stem and...
Tipo: Journal article
Palavras-chave: Stomatal closure; Net photosynthesis; Root histology; Oxygen injection; Root hypoxia; Subsurface drip irrigation.
Ano: 2009
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-58392009000100012