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	Provedor de dados AgEcon (1) Autor Buyuktahtakin, Esra (1) Feng, Zhuo (1) Frisvold, George B. (1) Olsson, Aaryn (1) Szidarovszky, Ferenc (1) Palavra-chave Crop Production/Industries (1) Environmental Economics and Policy (1) Integer programming (1) Invasive species (1) Q57 (1) Q58 (1) Mais... Tipo do documento Conference Paper or Presentation (1) Ano 2010 (1) País United States (1) Idioma Inglês (1)		Ordenar por:  Relevância Autor Título Ano Registros recuperados: 99 Primeira ... 1 2 3 4 5 ... Última Gas exchange and yield response to foliar phosphorus application in Phaseolus vulgaris L. under drought Braz. J. Plant Physiol. Santos,Mauro Guida dos; Ribeiro,Rafael Vasconcelos; Oliveira,Ricardo Ferraz de; Pimentel,Carlos. This study was conducted to evaluate the effect of foliar Pi application on gas exchange and yield of bean genotypes submitted to a mild water deficit at the pre-flowering stage. In the first experiment, when extra Pi (10 g.L-1) was sprayed on leaves during water stress or during recovery, there was no effect on gas exchange or yield in the A320, Carioca and Ouro Negro genotypes. However, net CO2 assimilation (A) of A320 and Ouro Negro was less affected, but not significantly, than Carioca at the end of the stress, when Pi was supplied five days before water deficit. In the second experiment, two different doses of Pi (10 and 20 g.Pi L-1) were sprayed five days before water deficit on the Carioca genotype. During the last three days of the mild water... Tipo: Info:eu-repo/semantics/article Palavras-chave: Common bean; Inorganic phosphorus; Photosynthesis; Water deficit. Ano: 2004 URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1677-04202004000300007 Impacts of drought and temperature stress on coffee physiology and production: a review Braz. J. Plant Physiol. DaMatta,Fábio M.; Ramalho,José D. Cochicho. Overall, drought and unfavourable temperatures are the major climatic limitations for coffee production. These limitations are expected to become increasingly important in several coffee growing regions due to the recognized changes in global climate, and also because coffee cultivation has spread towards marginal lands, where water shortage and unfavourable temperatures constitute major constraints to coffee yield. In this review, we examine the impacts of such limitations on the physiology, and consequently on the production of mainly Coffea arabica and C. canephora, which account for about 99 % of the world coffee bean production. The first section deals with climatic factors and the coffee plant’s requirements. The importance of controlling oxidative... Tipo: Info:eu-repo/semantics/article Palavras-chave: Coffea; Chilling; Frost; Heat; Photosynthesis; Water deficit; Water use; Yield. Ano: 2006 URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1677-04202006000100006 Use of physiological parameters as fast tools to screen for drought tolerance in sugarcane Braz. J. Plant Physiol. Silva,Marcelo de A.; Jifon,John L.; Silva,Jorge A.G. da; Sharma,Vivek. Drought is one of the major limitations to plant productivity worldwide. Identifying suitable screening tools and quantifiable traits would facilitate the crop improvement process for drought tolerance. In the present study, we evaluated the ability of four relatively physiological parameters (variable-to-maximum chlorophyll a fluorescence ratio, F v/F m; estimated leaf chlorophyll content via SPAD index; leaf temperature, LT; and, leaf relative water content, RWC) to distinguish between drought tolerant and susceptible sugarcane genotypes subjected to a 90-d drought cycle. Eight field-grown genotypes were studied. By 45 d after the onset of treatments, the F v/F m, SPAD index and RWC of drought-stressed plants had declined significantly in all genotypes... Tipo: Info:eu-repo/semantics/article Palavras-chave: Chlorophyll a fluorescence; Relative water content; Leaf temperature; Saccharum; Water deficit. Ano: 2007 URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1677-04202007000300003 Physiology of cashew plants grown under adverse conditions Braz. J. Plant Physiol. Bezerra,Marlos A.; Lacerda,Claudivan F. de; Gomes Filho,Enéas; Abreu,Carlos E. B. de; Prisco,José T.. The cashew (Anacardium occidentale L.) is an important crop for semi-arid agriculture and contributes to the social and economical development of several world regions, including the northeast of Brazil. In spite of its importance, very few studies aim to understand the effects of abiotic stresses on the development and yield of the cashew. This review covers the research on cashew ecophysiology, with emphasis on the effects of water and salt stress on its development, mineral nutrition and gas exchange processes. The results presented here were obtained at different plant growth stages and under different environmental conditions of soil and climate. The ecophysiological significance of this information is also discussed. Tipo: Info:eu-repo/semantics/article Palavras-chave: Anacardium occidentale; Development; Salt stress; Water deficit. Ano: 2007 URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1677-04202007000400012 Physiological and biochemical responses to drought stress in Barbados cherry Braz. J. Plant Physiol. Medeiros,David Barbosa; Silva,Elizamar Ciriaco da; Santos,Hugo Rafael Bentzen; Pacheco,Cinthya Mirella; Musser,Rosimar dos Santos; Nogueira,Rejane Jurema Mansur Custódio. To evaluate physiological genotypic differences between two Barbados cherry genotypes (13- and 14-CPA) under water deficit, initial growth, water relations, and organic solute accumulation were evaluated in an experiment performed using four-month-old seedlings, which were subjected to four water treatments (100, 75, 50, and 25% of field capacity), with five replications. Severe water deficit (25% of field capacity) negatively affected plant height, stem diameter, leaf area, dry matter of the leaves and stem to both genotypes, and root dry matter to genotype 13-CPA. Predawn (Ywpd) and midday leaf water potentials (Ywmd) were reduced in plants grown under 25% of field capacity, only in the genotype 14-CPA. There was not a change in relative water content,... Tipo: Info:eu-repo/semantics/article Palavras-chave: Malpighia emarginata DC; Soluble organic solutes; Biomass allocation; Water relations; Water deficit. Ano: 2012 URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1677-04202012000300005 The complexity-stability hypothesis in plant gas exchange under water deficit Braz. J. Plant Physiol. Souza,Gustavo M.; Pincus,Steven M; Monteiro,José Alberto F.. We hypothesized that more complex, i.e. irregular, temporal dynamics and a more interconnected overall network supports greater stability to gas exchange parameters (herein, CO2 net assimilation and transpiration) in plants under water deficit. To test this hypothesis two genotypes of Phaseolus vulgaris were subjected to a period of absence of irrigation, and subsequent rewatering to achieve recovery. Gas exchanges parameters were measured each 10 s during 6 h to obtain time series to evaluate complexity by Approximate Entropy (ApEn) calculations, and network connectance in each water regime. Notably, the Jalo Precoce genotype showed significantly more stability than the Guarumbé genotype under system perturbation, coincident with greater irregularity in... Tipo: Info:eu-repo/semantics/article Palavras-chave: Approximate Entropy; Complexity; Network connectance; Plant stress theory; Photosynthesis; Temporal dynamics; Water deficit. Ano: 2005 URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1677-04202005000400004 Ecophysiological responses to drought and salinity in the cosmopolitan invader Nicotiana glauca Braz. J. Plant Physiol. González,Armando; Tezara,Wilmer; Rengifo,Elizabeth; Herrera,Ana. Nicotiana glauca, a shrub native to southern South America, is widely distributed in the Americas, from Patagonia to the USA, from zero up to 3,700 m; it rapidly invades disturbed environments. In Venezuela, it has been reported from zero up to 2,000 m growing in contrasting conditions of relative humidity, temperature, rainfall, and salinity. In order to gain insight into the extent and mode of resistance to drought and salinity in N. glauca, we studied the effect of these factors on water relations and photosynthesis under both natural and greenhouse conditions. In the field, water potential, photosynthetic rate (A) and stomatal conductance (gs), but not relative water content (RWC) decreased because of drought. Manual removal of epicuticular wax... Tipo: Info:eu-repo/semantics/article Palavras-chave: Drought; Osmotic adjustment; Salinity; Water deficit. Ano: 2012 URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1677-04202012000300008 Leaf water potential, gas exchange and chlorophyll a fluorescence in acariquara seedlings (Minquartia guianensis Aubl.) under water stress and recovery Braz. J. Plant Physiol. Liberato,Maria Astrid Rocha; Gonçalves,José Francisco de Carvalho; Chevreuil,Larissa Ramos; Nina Junior,Adamir da Rocha; Fernandes,Andreia Varmes; Santos Junior,Ulysses Moreira dos. The physiological performance of acariquara (Minquartia guianensis) seedlings submitted to water deficit and the recovery of physiological parameters during rehydration were investigated in a greenhouse experiment. The analyzed parameters were: leaf water potential, gas exchange and chlorophyll a fluorescence. After thirty-five days, non-irrigated plants exhibited a leaf water potential 70 % lower compared to control plants (irrigated daily) and the stomatal conductance reached values close to zero, inducing a severe decrease in gas exchange (photosynthesis and transpiration). Six days after the beginning of the rehydration of drought-stressed plants, the results demonstrated that water stress did not irreversibly affect gas exchange and quantum efficiency... Tipo: Info:eu-repo/semantics/article Palavras-chave: Chlorophyll a fluorescence; Photochemical efficiency of PSII; Stress physiology; Tree species; Water deficit. Ano: 2006 URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1677-04202006000200008 Stomatal changes induced by intermittent drought in four umbu tree genotypes Braz. J. Plant Physiol. Silva,Elizamar C.; Nogueira,Rejane J. M. C.; Vale,Fernando H. A.; Araújo,Francisco P. de; Pimenta,Mariana A.. Transpiration (E), diffusive resistance (r s) and anatomical parameters were measured in plants of four grafted umbu tree genotypes (GBUs 44, 48, 50 and 68) in order to evaluate alterations induced by intermittent drought and possible genotypic variations. Transpiration measurements were taken daily until stomatal closure by withholding water. Measurements were also taken, when the plants were re-watered and the watering was interrupted again. This cycle was repeated for a period of 31 days (stress period). The control plants were also irrigated daily. A regular pattern in the stomatal opening/closing mechanism was observed throughout the watering period, exhibiting intra-specific differences. Stomatal behavior of GBU 44 and GBU 68 were influenced by air... Tipo: Info:eu-repo/semantics/article Palavras-chave: Diffusive resistance; Spondias tuberosa; Stomatal density; Transpiration; Water deficit. Ano: 2009 URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1677-04202009000100005 Water relations and some aspects of leaf metabolism of Jatropha curcas young plants under two water deficit levels and recovery Braz. J. Plant Physiol. Arcoverde,Gabriela B.; Rodrigues,Bruno M.; Pompelli,Marcelo F.; Santos,Mauro G.. Stomatal conductance (g s), transpiration (E), relative water content (RWC), superoxide dismutase activity (SOD), malondialdehyde (MDA), leaf carbohydrate soluble (LCS), free amino acids (FAA) and total protein (TP) content were measured under mild and severe drought stress in young potted Jatropha curcas L. in the greenhouse. The plants were kept for 12 days under three different water regimes, control (well hydrated), 50% irrigation control (mild stress) and 25% (severe stress), after rehydration were measured on the second and fourth day. Both mild and severe stress decreased g s and E; however, only severe stress reduced LCS, FAA and TP content and increased SOD activity (70%) and MDA content (60%) compared with the control. Moreover, under these... Tipo: Info:eu-repo/semantics/article Palavras-chave: Biodiesel; Drought tolerance; MDA; Oxidative stress; ROS; Water deficit. Ano: 2011 URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1677-04202011000200004 Exploring drought tolerance in coffee: a physiological approach with some insights for plant breeding Braz. J. Plant Physiol. DaMatta,Fábio Murilo. This paper briefly reviews some selected traits (leaf area, crown architecture, water-use efficiency and carbon isotope discrimination, water relations and root characteristics), which may be explored in breeding programmes to tolerance to drought stress in arabica and robusta coffee. Tipo: Info:eu-repo/semantics/article Palavras-chave: Coffea; Water deficit; Water use; Yield. Ano: 2004 URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1677-04202004000100001 Asymmetrical leaves induced by water deficit show asymmetric photosynthesis in common bean Braz. J. Plant Physiol. Souza,Gustavo Maia; Viana,Juliana de Oliveira Fernandes; Oliveira,Ricardo Ferraz de. In this study we tested the hypothesis that leaf asymmetric growth induced by water deficit in common bean (Phaseolus vulgaris L.) might be correlated with different net photosynthesis rates between the two opposed leaflets (right and left) considering a bilateral symmetric plane. In order to induce developmental instability, the drought-sensitive common bean genotype "Jalo Precoce" was subjected to periods of suspended irrigation during its vegetative growth. Developmental instability was evaluated by measurements of leaflets asymmetry, and the effects of drought on gas exchanges were taken in both symmetrical leaflets (right and left) in relation to the central leaflet. Water deficit induced an increase of 80 % in leaf asymmetry. Net photosynthesis of P.... Tipo: Info:eu-repo/semantics/article Palavras-chave: Developmental instability; Leaf symmetry; Water deficit. Ano: 2005 URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1677-04202005000200005 Foliar phosphorus supply and CO2 assimilation in common bean (Phaseolus vulgaris L.) under water deficit Braz. J. Plant Physiol. Santos,Mauro G. dos; Ribeiro,Rafael V.; Teixeira,Marcelo G.; Oliveira,Ricardo F. de; Pimentel,Carlos. Two common bean cultivars were grown in pots under greenhouse conditions. Plants were submitted to a foliar Pi spray two days before suspending irrigation, what enhanced net CO2 assimilation rate of Ouro Negro cultivar but did not change significantly the photosynthesis of Carioca cultivar under both water deficit and rehydration periods. The results revealed that a foliar Pi spray induced an up-regulation of photosynthesis in common bean under mild water deficit, with this effect being genotype-dependent. Tipo: Info:eu-repo/semantics/other Palavras-chave: Drought stress; Ortophosphate; Photosynthesis; Water deficit. Ano: 2006 URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1677-04202006000300007 Improved tolerance of wheat plants (Triticum aestivum L.) to drought stress and rewatering by the arbuscular mycorrhizal fungus Glomus claroideum: effect on growth and cell membrane stability Braz. J. Plant Physiol. Beltrano,José; Ronco,Marta G.. The aim of this paper was to investigate the contribution of the arbuscular mycorrhizal fungus Glomus claroideum to drought stress tolerance in wheat plants grown under controlled conditions in a growth chamber, and subjected to moderate or severe water stress and rewatering. Water stress tolerance was determined through total dry weight, leaf relative water content, leakage of solutes and leaf chlorophyll and protein concentrations in mycorrhizal and non-mycorrhizal wheat plants. Total dry weight and leaf chlorophyll concentrations were significantly higher in mycorrhizal plants after moderate or severe water stress treatments compared with non-mycorrhizal ones. Electrolyte leakage was significantly lower in water-stressed inoculated plants. Compared to... Tipo: Info:eu-repo/semantics/article Palavras-chave: Mycorrhizae; Relative water content; Rewatering; Solute leakage; Water deficit. Ano: 2008 URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1677-04202008000100004 Expolinear model on soybean growth in Argentina and Brazil Ciência Rural Confalone,Adriana Elisabet; Bernardes,Marcos Silveira; Costa,Luiz Claudio; Righi,Ciro Abbud; Dourado Neto,Durval; Martin,Thomas Newton; Manfron,Paulo Augusto; Pereira,Carlos Rodrigues. Predicting crop growth and yield with precision are one of the main concerns of the agricultural science. For these purpose mechanistic models of crop growth have been developed and tested worldwide. The feasibility of an expolinear model for crop growth was evaluated on predicting growth modification on soybean (Glycine max L. Merrill) of determined and undetermined growth cultivars, submitted to water restrictions imposed on different phenological stages. An experiment was carried out in Azul/Argentina and in Viçosa/Brazil during the growing seasons (1997/1998, 1998/1999 and 2002/2003). The expolinear model was adjusted to the dry-matter data obtained from each treatment. The model showed sensibility of Rm (maximum relative growth rate of the culture - g... Tipo: Info:eu-repo/semantics/article Palavras-chave: Water deficit; Solar radiation; Temperature; Phenological phase. Ano: 2010 URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0103-84782010000500002 Silicon foliar application attenuates the effects of water suppression on cowpea cultivars Ciência e Agrotecnologia Silva,Duval Chagas da; Melo,Alberto Soares de; Melo,Yuri Lima; Andrade,Wellerson Leite de; Lima,Liziane Maria de; Santos,Anderson Reges. ABSTRACT Silicon and proline play important physiological, metabolic and functional roles in plants, especially under water deficit conditions. Their application can mitigate the adverse effects of stress in crops by increasing water use efficiency and antioxidant activity. The objective of this study was to evaluate silicon (Si) as attenuator of the effects of water deficit on cowpea cultivars, through physiological, biochemical and growth indicators. The experimental design was randomized blocks with four cultivars (BRS Guariba, BRS Itaim, BRS Aracê and BRS Rouxinol) and four irrigation treatments associated or not with Si application (W100 - 100% ETo; W50 - 50% ETo; W50+100Si and W50+200Si, with 100 and 200 mg L-1 silicon, respectively), in a 4 x 4... Tipo: Info:eu-repo/semantics/article Palavras-chave: Vigna unguiculata (L.) Walp; Water deficit; Antioxidant enzymes; Osmotic adjustment. Ano: 2019 URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1413-70542019000100244 Hydrogen sulfide, potassium phosphite and zinc sulfate as alleviators of drought stress in sunflower plants Ciência e Agrotecnologia Almeida,Gabriel Martins; Silva,Adinan Alves da; Batista,Priscila Ferreira; Moura,Luciana Minervina de Freitas; Vital,Roberto Gomes; Costa,Alan Carlos. ABSTRACT Drought is the most harmful environmental factor crop productivity. Some chemicals are used in agriculture to mitigate the damage from this stress on plants. Therefore, we examined whether the spraying of zinc sulfate (ZS), potassium phosphite (KPhi) and the hydrogen sulfide (H2S) donor sodium hydrosulfide (NaHS) would mitigate the deleterious effects of water deficit on sunflower plants by analyzing physiological and biometric characteristics. The experiment was carried out in a greenhouse using a randomized block design with five replications. The treatments were arranged in a 4 x 2 factorial scheme: [Factor A (Alleviators)] - spraying of KPhi (0.5 L ha-1), ZS (3.2 kg ha-1), NaHS (1.2 g ha-1), and water; [Factor B (substrate humidity, SH)] -... Tipo: Info:eu-repo/semantics/article Palavras-chave: Photosynthesis; Water deficit; Malonaldehyde; Leaf water potential; Mitigating substance. Ano: 2020 URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1413-70542020000100225 Effect of different levels of water deficit on rapeseed (Brassica napus L.) crop Ciência e Agrotecnologia Bilibio,Carolina; Carvalho,Jacinto de Assunção; Hensel,Oliver; Richter,Uwe. Effects of different levels of water deficit applied during rapeseed crop development were assessed in a trial with metallic pots in greenhouse at the Department of Agricultural Engineering of Kassel University, Witzenhausen, Germany. A randomized block design was used with one cultivar (Ability Summer Rape) and three levels of water deficit (0, 30, and 60% of evapotranspiration) in three treatments and 20 replicates. Irrigation management was carried out through daily water balance, where ET = I - D; ET: evapotranspiration; I: irrigation; and D: drainage. The following evaluations were carried out weekly: stem diameter (mm); plant height (cm); number of leaves; number of branches and number of pods. At the end of the experiment, assessed total green... Tipo: Info:eu-repo/semantics/article Palavras-chave: Water management; Irrigation; Water deficit. Ano: 2011 URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1413-70542011000400005 Effects of different water regimes on the anatomical characteristics of roots of grasses promising for revegetation of areas surrounding hydroelectric reservoir Ciência e Agrotecnologia Silva,Silvana da; Castro,Evaristo Mauro de; Soares,Ângela Maria. The objective of this study was to evaluate the effect of different water regimes on some aspects of root anatomy of three grasses: Echinochloa pyramidalis (canarana), Setaria anceps (setária) and Paspalum paniculatum (paspalo). The plants were cultivated in a greenhouse and submitted to three water regimes: daily watering; suspension of watering and suspension of watering followed by submersion of the root system. Segments of the middle part of the roots were taken and submitted to classical techniques in botany for slide making and tissue analysis. Anatomical differences were observed among the three grasses submitted to water regimes regarding the number of cell layers in the external cortex and thickening of lignin and suberin. The submerged roots of... Tipo: Info:eu-repo/semantics/article Palavras-chave: Revegetation; Grasses; Water deficit; Echinochloa pyramidalis; Setaria anceps; Paspalum paniculatum; Flood; Aerenchyma; Anatomical characteristics; Roots. Ano: 2003 URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1413-70542003000200020 Registros recuperados: 99 Primeira ... 1 2 3 4 5 ... Última

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