Bread wheat (Triticum aestivum) is a major crop worldwide, and it is highly susceptible to heat. ... more Bread wheat (Triticum aestivum) is a major crop worldwide, and it is highly susceptible to heat. In this work, grain production and composition were evaluated in Portuguese T. aestivum germplasm (landraces and commercial varieties), which was subjected to heat after anthesis (grain filling stage). Heat increased the test weight (TW) in Nabão, Grécia and Restauração, indicating an improved flour-yield potential. Mocho de Espiga Branca (MEB) and Transmontano (T94) showed higher thousand-kernel weight (TKW). Gentil Rosso presented increased soluble sugars, which are yeast substrates in the bread-making process. Ardila stood out for its protein increase under heat. Overall SDS was unaffected by higher temperature, but increased in T94, indicating a better dough elasticity for bread-making purposes. Under heat, lipid content was maintained in most genotypes, being endogenous fatty acids (FAs) key players in fresh bread quality. Lipid unsaturation, evaluated through the double bond index ...
Coffee is one of the world’s most traded agricultural products. Modeling studies have predicted t... more Coffee is one of the world’s most traded agricultural products. Modeling studies have predicted that climate change will have a strong impact on the suitability of current cultivation areas, but these studies have not anticipated possible mitigating effects of the elevated atmospheric [CO2] because no information exists for the coffee plant. Potted plants from two genotypes of Coffea arabica and one of C. canephora were grown under controlled conditions of irradiance (800 μmol m-2 s-1), RH (75%) and 380 or 700 μL CO2 L-1 for 1 year, without water, nutrient or root development restrictions. In all genotypes, the high [CO2] treatment promoted opposite trends for stomatal density and size, which decreased and increased, respectively. Regardless of the genotype or the growth [CO2], the net rate of CO2 assimilation increased (34-49%) when measured at 700 than at 380 μL CO2 L-1. This result, together with the almost unchanged stomatal conductance, led to an instantaneous water use efficie...
Selenium is an antioxidant trace mineral important for human health and development. Therefore, t... more Selenium is an antioxidant trace mineral important for human health and development. Therefore, the growing demand for efficient, bioeconomic and sustainable strategies to increase Se content in cereals, namely, rice, is justified. In this context, biofortification is a strategy that can promote nutrient enhancement in food crops and, therefore, increased nutrient uptake in the human body. In this framework, a technical itinerary was implemented using a rice genotype (OP1509), through foliar spraying with two selenium concentrations (25 and 100 g Se.ha−1) of sodium selenate (Na2SeO4) and sodium selenite (Na2SeO3). It was found that the average Se biofortification index was 1.8–4.7- and 5.4–6.0-fold in selenate and selenite treatments, respectively. The contents of Se, Ca, Fe, K, P, C, H and O in brown rice grains were also quantified and it was found that both forms of fertilizers increased Zn contents with 25 g Se.ha−1, but decreased with 100 g Se.ha−1. Moreover, Ca only increased ...
Smart farming techniques can be used to maximize food production. This can be achieved by the rap... more Smart farming techniques can be used to maximize food production. This can be achieved by the rapid detection of variations in crops and clever use of resources such as water and fertilizers, which might minimize crop stress through direct target practices. In an orchard located in the West region of Portugal (GPS coordinates 39°23′28.997″ N; 9°4′52.483″ W), a Ca biofortification workflow with seven foliar sprays of CaCl2 (4 kg ha−1 and 8 kg ha−1) was used to increase Ca contents in “Rocha” pear trees. During the biofortification process, an Unmanned Aerial Vehicle, synchronized by GPS, was used to characterize the orchard regarding its morphology (slope) and to monitor trees (NDVI—Normalized Difference Vegetation Index). These data were correlated with Ca content (assessed by X-ray fluorescence analysis) and photoassimilate synthesis (assessed by leaf gas exchange measurements). The orchard showed no major slopes and after four sprays with CaCl2, NDVI values revealed no major diffe...
The Future of Rice Demand: Quality Beyond Productivity
Human micronutrient malnutrition, in particular selenium (Se) deficitary availability, affects mi... more Human micronutrient malnutrition, in particular selenium (Se) deficitary availability, affects millions of people around the world. Diet is the most important source of Se, and rice (Oryza sativa L.) is the most important staple crop for human consumption, feeding about half of the world’s population, thus with a unique potential to improve health through food. Selenium is an essential element for men and animals, having also important roles in plant metabolism. Several programs were implemented worldwide to mitigate an insufficiency micronutrient intake in humans, including Se. Among the used strategies, agronomic Se biofortification stands out as a feasible, efficient, fast, reliable, sustainable, more accessible, and cost-effective strategy, to respond to such widespread human malnutrition, particularly in rural areas and in developing countries, having the additional advantage of partly overcoming deficient distribution infrastructure and health systems in these regions. This review highlights the role of Se in human health and in plants, the Se agronomic biofortification success over the last two decades, focusing particularly in rice, and underlies the future challenges ahead to guarantee adequate healthy food products in a difficult and unfavorable context of growing population pressure and ongoing climate changes.
This study aimed to assess the efficiency of Ca enrichment in tubers of three genotypes of Solanu... more This study aimed to assess the efficiency of Ca enrichment in tubers of three genotypes of Solanum tuberosum L., through foliar spraying with CaCl2 and Ca(NO3)2 solutions. In this context, soil heterogeneity of three potato-growing fields, as well as the implications of Ca accumulation among tissues and some quality parameters were assessed. Three potato varieties (Agria, Picasso and Rossi) were grown in three production fields and during the life cycle, four pulverizations with calcium chloride (3 and 6 kg ha−1) or calcium nitrate (0.5, 2 and 4 kg ha−1) were applied. For screening the potential phytotoxicity, using Agria as a test system, the potential synthesis of photoassimilates was determined, and it was found that after the 3rd Ca application, leaf gas exchanges were moderately (net photosynthesis), to strongly (stomatal conductance) affected, although without impact on Ca accumulation in tubers. At harvest, the average Ca biofortification index varied between 5–40%, 40–35% an...
The predicted enhancement of air [CO2] and of global climate changes in this century, linked, e.g... more The predicted enhancement of air [CO2] and of global climate changes in this century, linked, e.g., to increased temperatures, appear as a risk factor for coffee crop according to it agroclimatic zoning. However, after exposure to long-term adverse conditions, plants may trigger acclimation/tolerance mechanisms. Furthermore, the positive impact of the enhanced [CO2] on the photosynthetic metabolism (and absence of down regulation) might help to mitigate the effects of high temperature on the coffee plant, which was never characterized for Coffea sp.. Therefore, this study aims at linking the physiological and biochemical responses of coffee to temperature and [CO2] changes IX Simposio de Pesquisa dos Cafes do Brasil 24 a 26 de junho de 2015, Curitiba PR using the photosynthetic metabolism as probe to evaluate the acclimation and tolerance of the plant. For that, Coffea arabica L. cv. IPR 108 plants were grown for one year at 25/20 oC (day/night) and under controlled conditions (temp...
Due to the rapid growth of the population worldwide and the need of providing food safety in larg... more Due to the rapid growth of the population worldwide and the need of providing food safety in large crop productions, UAVs (Unmanned Aerial Vehicles) are being used in agriculture to provide valuable data for decision making. Accordingly, through precision agriculture, an efficient management of resources, using data obtained by the technologies, is possible. Through remote sensed, data collected in a crop region, it is possible to create NDVI (Normalized Difference Vegetation Index) maps, which are a powerful tool to detect, namely stresses in plants. Accordingly, using some Smart Farm technology, this study aimed to access the impact of Ca biofortification process in leaves of Solanum tuberosum L. cv. Picasso. As such, using as a test system, an experimental production field of potato tubers (GPS coordinates 39o 16’ 38,816’’ N; 9o 15’ 9,128’’W), plants were submitted to a Ca biofortification workflow through foliar spraying with CaCl2 or, alternatively, chelated calcium (Ca-EDTA) a...
This article is an open access article distributed under the terms and conditions of the Creative... more This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY
O calor e a seca constituem as principais limitacoes ao crescimento e produtividade das plantas, ... more O calor e a seca constituem as principais limitacoes ao crescimento e produtividade das plantas, e a sua ocorrencia conjunta tende a agravar os niveis de estresse. Este trabalho teve como objetivo estudar o impacto nas trocas gasosas foliares em plantas de Coffea arabica L. cv. Icatu e C. canephora cv. Conilon Clone 153 submetidas a duas condicoes hidricas (bem regadas, Ctl; seca severa, SS) em condicoes adequadas de temperatura (25/20°C, dia/noite), e a posterior aumento gradual de temperatura ate 42/30 oC, seguido de um periodo de recuperacao de 14 dias (Rec14) apos reposicao das condicoes controle de disponibilidade hidrica e temperatura. Foram avaliados parâmetros foliares relacionados as taxas de fotossintese liquida ( P n ), condutância estomatica para o vapor de agua ( g s ) e transpiracao ( E ). Os resultados evidenciaram fortes impactos em SS em P n , g s , E de ambos os genotipos. A exposicao apenas ao aumento de temperatura provocou impactos diferentes. Nas plantas de CL1...
Low temperatures affect many plant physiological and biochemical components, namely membrane lipi... more Low temperatures affect many plant physiological and biochemical components, namely membrane lipids. The present work aimed to characterize the total fatty acid (TFA) content of class lipid composition of chloroplast membranes of 2 genotypes from the most important commercial coffee species, Coffea arabica cv. Catuai and Coffea canephora cv. Conilon clone 02, under adequate environmental conditions, as well as after some of the adjustments triggered during a gradual temperature decrease, upon chilling exposure and in the following recovery period. Under adequate temperature (25/20 oC, day/night) the lipid composition of chloroplast membranes did not show striking differences concerning the TFA content and the main lipid classes (both in content and relative weight). Galactolipid classes monogalactosildiacilglicerol (MGDG) and digalactosildiacilglicerol (DGDG) dominate over the phospholipid ones, representing together (MGDG + DGDG) 77% (Catuai) and 85% (clone 02), with DGDG prevailin...
Universidade Federal de Goias UFG, Escola de Agronomia e Engenharia de Alimentos. Campus II Samam... more Universidade Federal de Goias UFG, Escola de Agronomia e Engenharia de Alimentos. Campus II Samambaia. Caixa Postal 131, 74001-970, Goiânia GO, Brazil Universidade Estadual do Norte Fluminense Darcy Ribeiro UENF, Centro de Ciencias e Tecnologias Agropecuarias. Av. Alberto Lamego 2000, Parque California, 28013-602, Campos dos Goytacazes RJ, Brazil L-Instituto Nacional de Investigacao Agraria / INRB, Av. Republica, Quinta do Marques 2784-505 Oeiras, Portugal Centro de Ecofisiologia, Bioquimica e Biotecnologia Vegetal / Inst. Inv. Cientifica Tropical, Av. Republica, Quinta do Marques, 2784-505 Oeiras, Portugal
O calor e a seca constituem as principais limitacoes ao crescimento e produtividade das plantas e... more O calor e a seca constituem as principais limitacoes ao crescimento e produtividade das plantas e a sua ocorrencia conjunta tende a agravar os niveis de estresse. Este trabalho pretendeu estudar as alteracoes estomaticas foliares em plantas de Coffea arabica L. cv. Icatu e C. canephora cv. Conilon Clone 153 submetidas a duas condicoes hidricas (bem regadas, Ctl; seca severa, SS) em condicoes adequadas de temperatura (25/20 °C, dia/noite), e a posterior aumento gradual de temperatura ate 42/30 oC, seguido de um periodo de recuperacao de 14 dias (Rec14) apos reposicao das condicoes controle de disponibilidade hidrica e temperatura. Foram avaliados parâmetros estomaticos foliares como: densidade estomatica, indice estomatico e tamanho de estomatos. Verificaram-se modificacoes das caracteristicas estomaticas, promovidas pela seca e temperatura, e dependentes da especie. A densidade estomatica (DE) em CL153 nao foi alterada com o estresse hidrico, enquanto que a area dos estomatos diminu...
Low positive temperatures may influence several plant physiological and biochemical components. H... more Low positive temperatures may influence several plant physiological and biochemical components. However, plants possess acclimation mechanisms that confer higher tolerance to such limiting conditions and better recovery ability after the stress. The objective of the present work was to characterize the changes of the contents of soluble sugars in Coffea canephora and C. arabica genotypes submitted to low positive temperatures, in order to elucidate the mechanisms involved in cold tolerance/sensitivity. One year old plants were placed under control conditions of 25/20 oC (day/night), irradiance of 700-900 μmol m , 70% de umidade relativa e fotoperiodo de 12h durante cerca de 10 dias. As plantas foram depois submetidas sucessivamente a um decrescimo gradual da temperatura (0,5oC diarios), desde 25/20oC ate 13/8oC, 3 dias a 13/4oC e 14 dias de recuperacao. Durante o experimento foram avaliados, ao nivel foliar, a concentracao de acucares soluveis. Os genotipos estudados apresentam sens...
The human metabolism requires Fe to support growth and the immune system. Iron further plays an e... more The human metabolism requires Fe to support growth and the immune system. Iron further plays an essential role in the synthesis of oxygen transport proteins (namely, hemoglobin and myoglobin), while its deficiency can lead to anemia. Zinc also plays major physiological roles, working in multiple basic biochemical functions in the cells of the organism, with its deficiency triggering multiple systems, namely gastrointestinal, central nervous, immune, and reproductive. Considering the physiological impact of these both micronutrients, this study aimed to develop a technological workflow for biofortification of tomato (Lycopersicum esculentum L.) fruits (variety beef heart) in Fe and Zn, following an organic production mode. The experimental field was selected considering the edaphoclimatic parameters and the protocols for tomato growth according to the organic production mode. Four foliar applications were carried out during the production cycle, with a mix of two products (Zitrilon –...
Growing water restrictions associated with climate changes constitute daunting challenges to crop... more Growing water restrictions associated with climate changes constitute daunting challenges to crop performance. This study unveils the impacts of moderate (MWD) or severe (SWD) water deficit, and their interaction with air [CO2], on the photosynthetic apparatus of Coffea canephora Pierre ex A. Froehner cv. Conilon Clone 153 (CL153) and Coffea arabica L. cv. Icatu. Seven year-old potted plants grown under 380 (aCO2) or 700 μl l −1 (eCO2) [CO2] gradually reached predawn water potentials between −1.6 and −2.1 MPa (MWD), and below −3.5 MPa (SWD). Under drought, stomata closure was chiefly related to abscisic acid (ABA) rise. Increasing drought severity progressively affected gas exchange and fluorescence parameters in both genotypes, with non-stomatal limitations becoming gradually dominating, especially regarding the photochemical and biochemical components of CL153 SWD plants. In contrast, Icatu plants were highly tolerant to SWD, with minor, if any, negative impacts on the potential p...
Bread wheat (Triticum aestivum) is a major crop worldwide, and it is highly susceptible to heat. ... more Bread wheat (Triticum aestivum) is a major crop worldwide, and it is highly susceptible to heat. In this work, grain production and composition were evaluated in Portuguese T. aestivum germplasm (landraces and commercial varieties), which was subjected to heat after anthesis (grain filling stage). Heat increased the test weight (TW) in Nabão, Grécia and Restauração, indicating an improved flour-yield potential. Mocho de Espiga Branca (MEB) and Transmontano (T94) showed higher thousand-kernel weight (TKW). Gentil Rosso presented increased soluble sugars, which are yeast substrates in the bread-making process. Ardila stood out for its protein increase under heat. Overall SDS was unaffected by higher temperature, but increased in T94, indicating a better dough elasticity for bread-making purposes. Under heat, lipid content was maintained in most genotypes, being endogenous fatty acids (FAs) key players in fresh bread quality. Lipid unsaturation, evaluated through the double bond index ...
Coffee is one of the world’s most traded agricultural products. Modeling studies have predicted t... more Coffee is one of the world’s most traded agricultural products. Modeling studies have predicted that climate change will have a strong impact on the suitability of current cultivation areas, but these studies have not anticipated possible mitigating effects of the elevated atmospheric [CO2] because no information exists for the coffee plant. Potted plants from two genotypes of Coffea arabica and one of C. canephora were grown under controlled conditions of irradiance (800 μmol m-2 s-1), RH (75%) and 380 or 700 μL CO2 L-1 for 1 year, without water, nutrient or root development restrictions. In all genotypes, the high [CO2] treatment promoted opposite trends for stomatal density and size, which decreased and increased, respectively. Regardless of the genotype or the growth [CO2], the net rate of CO2 assimilation increased (34-49%) when measured at 700 than at 380 μL CO2 L-1. This result, together with the almost unchanged stomatal conductance, led to an instantaneous water use efficie...
Selenium is an antioxidant trace mineral important for human health and development. Therefore, t... more Selenium is an antioxidant trace mineral important for human health and development. Therefore, the growing demand for efficient, bioeconomic and sustainable strategies to increase Se content in cereals, namely, rice, is justified. In this context, biofortification is a strategy that can promote nutrient enhancement in food crops and, therefore, increased nutrient uptake in the human body. In this framework, a technical itinerary was implemented using a rice genotype (OP1509), through foliar spraying with two selenium concentrations (25 and 100 g Se.ha−1) of sodium selenate (Na2SeO4) and sodium selenite (Na2SeO3). It was found that the average Se biofortification index was 1.8–4.7- and 5.4–6.0-fold in selenate and selenite treatments, respectively. The contents of Se, Ca, Fe, K, P, C, H and O in brown rice grains were also quantified and it was found that both forms of fertilizers increased Zn contents with 25 g Se.ha−1, but decreased with 100 g Se.ha−1. Moreover, Ca only increased ...
Smart farming techniques can be used to maximize food production. This can be achieved by the rap... more Smart farming techniques can be used to maximize food production. This can be achieved by the rapid detection of variations in crops and clever use of resources such as water and fertilizers, which might minimize crop stress through direct target practices. In an orchard located in the West region of Portugal (GPS coordinates 39°23′28.997″ N; 9°4′52.483″ W), a Ca biofortification workflow with seven foliar sprays of CaCl2 (4 kg ha−1 and 8 kg ha−1) was used to increase Ca contents in “Rocha” pear trees. During the biofortification process, an Unmanned Aerial Vehicle, synchronized by GPS, was used to characterize the orchard regarding its morphology (slope) and to monitor trees (NDVI—Normalized Difference Vegetation Index). These data were correlated with Ca content (assessed by X-ray fluorescence analysis) and photoassimilate synthesis (assessed by leaf gas exchange measurements). The orchard showed no major slopes and after four sprays with CaCl2, NDVI values revealed no major diffe...
The Future of Rice Demand: Quality Beyond Productivity
Human micronutrient malnutrition, in particular selenium (Se) deficitary availability, affects mi... more Human micronutrient malnutrition, in particular selenium (Se) deficitary availability, affects millions of people around the world. Diet is the most important source of Se, and rice (Oryza sativa L.) is the most important staple crop for human consumption, feeding about half of the world’s population, thus with a unique potential to improve health through food. Selenium is an essential element for men and animals, having also important roles in plant metabolism. Several programs were implemented worldwide to mitigate an insufficiency micronutrient intake in humans, including Se. Among the used strategies, agronomic Se biofortification stands out as a feasible, efficient, fast, reliable, sustainable, more accessible, and cost-effective strategy, to respond to such widespread human malnutrition, particularly in rural areas and in developing countries, having the additional advantage of partly overcoming deficient distribution infrastructure and health systems in these regions. This review highlights the role of Se in human health and in plants, the Se agronomic biofortification success over the last two decades, focusing particularly in rice, and underlies the future challenges ahead to guarantee adequate healthy food products in a difficult and unfavorable context of growing population pressure and ongoing climate changes.
This study aimed to assess the efficiency of Ca enrichment in tubers of three genotypes of Solanu... more This study aimed to assess the efficiency of Ca enrichment in tubers of three genotypes of Solanum tuberosum L., through foliar spraying with CaCl2 and Ca(NO3)2 solutions. In this context, soil heterogeneity of three potato-growing fields, as well as the implications of Ca accumulation among tissues and some quality parameters were assessed. Three potato varieties (Agria, Picasso and Rossi) were grown in three production fields and during the life cycle, four pulverizations with calcium chloride (3 and 6 kg ha−1) or calcium nitrate (0.5, 2 and 4 kg ha−1) were applied. For screening the potential phytotoxicity, using Agria as a test system, the potential synthesis of photoassimilates was determined, and it was found that after the 3rd Ca application, leaf gas exchanges were moderately (net photosynthesis), to strongly (stomatal conductance) affected, although without impact on Ca accumulation in tubers. At harvest, the average Ca biofortification index varied between 5–40%, 40–35% an...
The predicted enhancement of air [CO2] and of global climate changes in this century, linked, e.g... more The predicted enhancement of air [CO2] and of global climate changes in this century, linked, e.g., to increased temperatures, appear as a risk factor for coffee crop according to it agroclimatic zoning. However, after exposure to long-term adverse conditions, plants may trigger acclimation/tolerance mechanisms. Furthermore, the positive impact of the enhanced [CO2] on the photosynthetic metabolism (and absence of down regulation) might help to mitigate the effects of high temperature on the coffee plant, which was never characterized for Coffea sp.. Therefore, this study aims at linking the physiological and biochemical responses of coffee to temperature and [CO2] changes IX Simposio de Pesquisa dos Cafes do Brasil 24 a 26 de junho de 2015, Curitiba PR using the photosynthetic metabolism as probe to evaluate the acclimation and tolerance of the plant. For that, Coffea arabica L. cv. IPR 108 plants were grown for one year at 25/20 oC (day/night) and under controlled conditions (temp...
Due to the rapid growth of the population worldwide and the need of providing food safety in larg... more Due to the rapid growth of the population worldwide and the need of providing food safety in large crop productions, UAVs (Unmanned Aerial Vehicles) are being used in agriculture to provide valuable data for decision making. Accordingly, through precision agriculture, an efficient management of resources, using data obtained by the technologies, is possible. Through remote sensed, data collected in a crop region, it is possible to create NDVI (Normalized Difference Vegetation Index) maps, which are a powerful tool to detect, namely stresses in plants. Accordingly, using some Smart Farm technology, this study aimed to access the impact of Ca biofortification process in leaves of Solanum tuberosum L. cv. Picasso. As such, using as a test system, an experimental production field of potato tubers (GPS coordinates 39o 16’ 38,816’’ N; 9o 15’ 9,128’’W), plants were submitted to a Ca biofortification workflow through foliar spraying with CaCl2 or, alternatively, chelated calcium (Ca-EDTA) a...
This article is an open access article distributed under the terms and conditions of the Creative... more This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY
O calor e a seca constituem as principais limitacoes ao crescimento e produtividade das plantas, ... more O calor e a seca constituem as principais limitacoes ao crescimento e produtividade das plantas, e a sua ocorrencia conjunta tende a agravar os niveis de estresse. Este trabalho teve como objetivo estudar o impacto nas trocas gasosas foliares em plantas de Coffea arabica L. cv. Icatu e C. canephora cv. Conilon Clone 153 submetidas a duas condicoes hidricas (bem regadas, Ctl; seca severa, SS) em condicoes adequadas de temperatura (25/20°C, dia/noite), e a posterior aumento gradual de temperatura ate 42/30 oC, seguido de um periodo de recuperacao de 14 dias (Rec14) apos reposicao das condicoes controle de disponibilidade hidrica e temperatura. Foram avaliados parâmetros foliares relacionados as taxas de fotossintese liquida ( P n ), condutância estomatica para o vapor de agua ( g s ) e transpiracao ( E ). Os resultados evidenciaram fortes impactos em SS em P n , g s , E de ambos os genotipos. A exposicao apenas ao aumento de temperatura provocou impactos diferentes. Nas plantas de CL1...
Low temperatures affect many plant physiological and biochemical components, namely membrane lipi... more Low temperatures affect many plant physiological and biochemical components, namely membrane lipids. The present work aimed to characterize the total fatty acid (TFA) content of class lipid composition of chloroplast membranes of 2 genotypes from the most important commercial coffee species, Coffea arabica cv. Catuai and Coffea canephora cv. Conilon clone 02, under adequate environmental conditions, as well as after some of the adjustments triggered during a gradual temperature decrease, upon chilling exposure and in the following recovery period. Under adequate temperature (25/20 oC, day/night) the lipid composition of chloroplast membranes did not show striking differences concerning the TFA content and the main lipid classes (both in content and relative weight). Galactolipid classes monogalactosildiacilglicerol (MGDG) and digalactosildiacilglicerol (DGDG) dominate over the phospholipid ones, representing together (MGDG + DGDG) 77% (Catuai) and 85% (clone 02), with DGDG prevailin...
Universidade Federal de Goias UFG, Escola de Agronomia e Engenharia de Alimentos. Campus II Samam... more Universidade Federal de Goias UFG, Escola de Agronomia e Engenharia de Alimentos. Campus II Samambaia. Caixa Postal 131, 74001-970, Goiânia GO, Brazil Universidade Estadual do Norte Fluminense Darcy Ribeiro UENF, Centro de Ciencias e Tecnologias Agropecuarias. Av. Alberto Lamego 2000, Parque California, 28013-602, Campos dos Goytacazes RJ, Brazil L-Instituto Nacional de Investigacao Agraria / INRB, Av. Republica, Quinta do Marques 2784-505 Oeiras, Portugal Centro de Ecofisiologia, Bioquimica e Biotecnologia Vegetal / Inst. Inv. Cientifica Tropical, Av. Republica, Quinta do Marques, 2784-505 Oeiras, Portugal
O calor e a seca constituem as principais limitacoes ao crescimento e produtividade das plantas e... more O calor e a seca constituem as principais limitacoes ao crescimento e produtividade das plantas e a sua ocorrencia conjunta tende a agravar os niveis de estresse. Este trabalho pretendeu estudar as alteracoes estomaticas foliares em plantas de Coffea arabica L. cv. Icatu e C. canephora cv. Conilon Clone 153 submetidas a duas condicoes hidricas (bem regadas, Ctl; seca severa, SS) em condicoes adequadas de temperatura (25/20 °C, dia/noite), e a posterior aumento gradual de temperatura ate 42/30 oC, seguido de um periodo de recuperacao de 14 dias (Rec14) apos reposicao das condicoes controle de disponibilidade hidrica e temperatura. Foram avaliados parâmetros estomaticos foliares como: densidade estomatica, indice estomatico e tamanho de estomatos. Verificaram-se modificacoes das caracteristicas estomaticas, promovidas pela seca e temperatura, e dependentes da especie. A densidade estomatica (DE) em CL153 nao foi alterada com o estresse hidrico, enquanto que a area dos estomatos diminu...
Low positive temperatures may influence several plant physiological and biochemical components. H... more Low positive temperatures may influence several plant physiological and biochemical components. However, plants possess acclimation mechanisms that confer higher tolerance to such limiting conditions and better recovery ability after the stress. The objective of the present work was to characterize the changes of the contents of soluble sugars in Coffea canephora and C. arabica genotypes submitted to low positive temperatures, in order to elucidate the mechanisms involved in cold tolerance/sensitivity. One year old plants were placed under control conditions of 25/20 oC (day/night), irradiance of 700-900 μmol m , 70% de umidade relativa e fotoperiodo de 12h durante cerca de 10 dias. As plantas foram depois submetidas sucessivamente a um decrescimo gradual da temperatura (0,5oC diarios), desde 25/20oC ate 13/8oC, 3 dias a 13/4oC e 14 dias de recuperacao. Durante o experimento foram avaliados, ao nivel foliar, a concentracao de acucares soluveis. Os genotipos estudados apresentam sens...
The human metabolism requires Fe to support growth and the immune system. Iron further plays an e... more The human metabolism requires Fe to support growth and the immune system. Iron further plays an essential role in the synthesis of oxygen transport proteins (namely, hemoglobin and myoglobin), while its deficiency can lead to anemia. Zinc also plays major physiological roles, working in multiple basic biochemical functions in the cells of the organism, with its deficiency triggering multiple systems, namely gastrointestinal, central nervous, immune, and reproductive. Considering the physiological impact of these both micronutrients, this study aimed to develop a technological workflow for biofortification of tomato (Lycopersicum esculentum L.) fruits (variety beef heart) in Fe and Zn, following an organic production mode. The experimental field was selected considering the edaphoclimatic parameters and the protocols for tomato growth according to the organic production mode. Four foliar applications were carried out during the production cycle, with a mix of two products (Zitrilon –...
Growing water restrictions associated with climate changes constitute daunting challenges to crop... more Growing water restrictions associated with climate changes constitute daunting challenges to crop performance. This study unveils the impacts of moderate (MWD) or severe (SWD) water deficit, and their interaction with air [CO2], on the photosynthetic apparatus of Coffea canephora Pierre ex A. Froehner cv. Conilon Clone 153 (CL153) and Coffea arabica L. cv. Icatu. Seven year-old potted plants grown under 380 (aCO2) or 700 μl l −1 (eCO2) [CO2] gradually reached predawn water potentials between −1.6 and −2.1 MPa (MWD), and below −3.5 MPa (SWD). Under drought, stomata closure was chiefly related to abscisic acid (ABA) rise. Increasing drought severity progressively affected gas exchange and fluorescence parameters in both genotypes, with non-stomatal limitations becoming gradually dominating, especially regarding the photochemical and biochemical components of CL153 SWD plants. In contrast, Icatu plants were highly tolerant to SWD, with minor, if any, negative impacts on the potential p...
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