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Raimundo Santos Barros - One of the best experts on this subject based on the ideXlab platform.
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seasonal changes in vegetative growth and photosynthesis of Arabica Coffee trees
Field Crops Research, 2004Co-Authors: Emerson Alves Da Silva, Fabio M Damatta, Carlos Ducatti, Adair Jose Regazzi, Raimundo Santos BarrosAbstract:Abstract Seasonal changes in vegetative growth, leaf gas exchanges, carbon isotope discrimination (Δ) and carbohydrate status were monitored in de-fruited Coffee trees (Coffea Arabica L.) grown in the field, from October 1998 through September 1999, in Vicosa (20°45′S, 42°15′W, 650 m a.s.l.), southeastern Brazil. Of the total growth over the 12-month study period, 78% occurred in the warm, rainy season (October–March), and 22% during the cool, dry season (April–September). Throughout the active growth period, the rate of net carbon assimilation (A) averaged 8.6 μmol m−2 s−1, against 3.4 μmol m−2 s−1 during the period of reduced growth. In the active period, growth, unlike A or Δ, was strongly negatively correlated with air temperature. In contrast, growth and A were both correlated positively, and Δ correlated negatively, with air temperature during the reduced growth period. However, the depressions of A and growth might have simply run in parallel, without any causal relationship. Changes in A appeared to be largely due to stomatal limitations in the active growing season, with non-stomatal ones prevailing in the slow growth period. Foliar carbohydrates seemed not to have contributed appreciably to changes in growth rates and photosynthesis.
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seasonal changes in vegetative growth and photosynthesis of Arabica Coffee trees
Field Crops Research, 2004Co-Authors: Emerson Alves Da Silva, Fabio M Damatta, Carlos Ducatti, Adair Jose Regazzi, Raimundo Santos BarrosAbstract:Seasonal changes in vegetative growth, leaf gas exchanges, carbon isotope discrimination (D) and carbohydrate status were monitored in de-fruited Coffee trees (Coffea Arabica L.) grown in the field, from October 1998 through September 1999, in Vicosa (20845 0 S, 42815 0 W, 650 m a.s.l.), southeastern Brazil. Of the total growth over the 12-month study period, 78% occurred in the warm, rainy season (October-March), and 22% during the cool, dry season (April-September). Throughout the active growth period, the rate of net carbon assimilation (A) averaged 8.6 mmol m � 2 s � 1 , against 3.4 mmol m � 2 s � 1 during the period of reduced growth. In the active period, growth, unlike A or D, was strongly negatively correlated with air temperature. In contrast, growth and A were both correlated positively, and D correlated negatively, with air temperature during the reduced growth period. However, the depressions of A and growth might have simply run in parallel, without any causal relationship. Changes in A appeared to be largely due to stomatal limitations in the active growing season, with non-stomatal ones prevailing in the slow growth period. Foliar carbohydrates seemed not to have contributed appreciably to changes in growth rates and photosynthesis. # 2004 Elsevier B.V. All rights reserved.
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decline of vegetative growth in coffea Arabica l in relation to leaf temperature water potential and stomatal conductance
Field Crops Research, 1997Co-Authors: Raimundo Santos Barros, Jay Wallace Da S E Mota, Fabio M Da Matta, Moacyr MaestriAbstract:Abstract The decline of vegetative growth of Arabica Coffee trees in Vicosa (20° 45′ S, 650 m altitude), Brazil, occurring from mid-March through late May, was observed in both irrigated and non-irrigated plants and did not show a direct relation with leaf water potential. Declining growth coincided with lowering temperatures, and particularly with increasing daily periods with low temperatures. Stomatal conductances in the morning (0800–0900 h) were relatively high until mid-March and decreased gradually in parallel with declining growth rates. During the quiescent growth phase in the cool season, starting from late May, stomata were closed for most of the diurnal period.
Olivier Honnay - One of the best experts on this subject based on the ideXlab platform.
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conserving wild Arabica Coffee emerging threats and opportunities
Agriculture Ecosystems & Environment, 2017Co-Authors: Raf Aerts, Gezahegn Berecha, Bart Muys, Lore Geeraert, Kitessa Hundera, Hanne De Kort, Olivier HonnayAbstract:Abstract Climate change and emerging pests and diseases are posing important challenges to global crop productivity, including that of Arabica Coffee. The genetic basis of commercially used Arabica Coffee cultivars is extremely narrow, and it is uncertain how much genetic diversity is present in ex situ collections. Conserving the wild Arabica Coffee gene pool and its evolutionary potential present in the montane forests of SW Ethiopia is thus critically important for maintaining Coffee yield and yield stability worldwide. Globally, Coffee agroforestry helps to conserve forest cover and forest biodiversity that cannot persist in open agricultural landscapes, but the conservation of the wild Arabica Coffee gene pool requires other priorities than those that are usually set for conserving forest biodiversity in mixed tropical landscapes. We show how forest loss and degradation, Coffee management, in particular production intensification, and the introduction of cultivars, are threatening the genetic integrity of these wild populations. We propose an active land sparing approach based on strict land use zoning to conserve the genetic resources and the in situ evolutionary potential of Arabica Coffee and discuss the major challenges including the development of access and benefit sharing mechanisms for ensuring long-term support to conservation.
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changing soil characteristics alter the arbuscular mycorrhizal fungi communities of Arabica Coffee coffea Arabica in ethiopia across a management intensity gradient
Soil Biology & Biochemistry, 2015Co-Authors: Matthias De Beenhouwer, Maarten Van Geel, Tobias Ceulemans, Diriba Muleta, Bart Lievens, Olivier HonnayAbstract:Coffee is the most important tropical agricultural commodity worldwide, cultivated in more than 70 countries. Despite the plant's huge economic importance, there is very limited knowledge on the association of arbuscular mycorrhizal fungi (AMF) with Coffee roots. We investigated the environmental drivers affecting the diversity and community composition of AMF on Arabica Coffee in its Ethiopian center of origin. We used 454 amplicon pyrosequencing to describe AMF communities in the roots of Arabica Coffee plants that were sampled along a large management intensity gradient, covering the major Ethiopian Coffee production systems. We identified AMF genera that have not been reported before in Arabica Coffee production regions elsewhere in the world and show that high soil phosphorus availability decreases AMF diversity and that soil pH, nitrogen and phosphorus availability strongly affect AMF community composition. At the scale of our study (max. 82 km distance between sampling points, and 770 m altitude difference), no effect was found of spatial location or altitude on AMF communities. This is the first study analyzing the drivers of naturally occurring AMF in the roots of a globally important tropical crop, providing preliminary data to improve Coffee production in its native and introduced range, through targeted intervention in Coffee AMF communities.
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effects of forest management on mating patterns pollen flow and intergenerational transfer of genetic diversity in wild Arabica Coffee coffea Arabica l from afromontane rainforests
Biological Journal of The Linnean Society, 2014Co-Authors: Katrien Vandepitte, Sabine Van Glabeke, Gezahegn Berecha, Raf Aerts, Bart Muys, Isabel Roldanruiz, Olivier HonnayAbstract:Coffea Arabica, the wild ancestor of all commercial Arabica Coffee cultivars worldwide, is endemic to the montane rainforests of Ethiopia. These forests, which harbour the most important C. Arabica gene pool, are threatened by increasing anthropogenic disturbance, potentially altering the mating patterns, pollen dispersal and maintenance of genetic diversity in C. Arabica understorey populations. We genotyped 376 adult Coffee shrubs and 418 progenies from three natural unmanaged, and three highly managed Coffee populations, using 24 microsatellite markers. Mating system analysis of C. Arabica yielded an overall multilocus outcrossing rate of 76%, which contrasts with the common knowledge that C. Arabica is a predominantly selfing species. In highly managed Coffee populations, paternity could be assigned to 78% of the progenies, whereas in the unmanaged natural Coffee populations, only 57% of the progenies could be assigned to a father, indicating reduced long-distance pollen dispersal in managed forests. Furthermore, the fraction of selfed progenies was significantly higher in managed (23%) than unmanaged (10%) Coffee forests. Finally, the lack of spatial genetic structure in all studied populations suggests high seed dispersal in unmanaged populations, and intense berry harvesting and Coffee planting in the managed populations. Our results imply that in situ conservation of the wild gene pool of C. Arabica must focus on limiting intensification of Coffee forest management, as decreased pollen dispersal and increased selfing in C. Arabica in intensively managed populations may increase the risk of genetic erosion. © 2014 The Linnean Society of London, Biological Journal of the Linnean Society, 2014, 112, 76–88.
Maria Brigida Dos Santos Scholz - One of the best experts on this subject based on the ideXlab platform.
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correlation between the composition of green Arabica Coffee beans and the sensory quality of Coffee brews
Food Chemistry, 2019Co-Authors: Mayara De Souza Gois Barbosa, Maria Brigida Dos Santos Scholz, Cintia Sorane Good Kitzberger, Marta De Toledo BenassiAbstract:This research aimed to correlate the composition of green Arabica Coffee beans with the sensory quality Coffee brews. The chemical composition of green Arabica Coffee bean (66 samples) from three Coffee quality contests was analyzed by near-infrared spectroscopy. Coffee brews with lower quality scores were correlated with high levels of caffeine, protein, chlorogenic acids and total titratable acidity (TTA) in the green Coffee beans. High sucrose/TTA and cafestol/kahweol ratios in the green Coffee beans were usually associated with higher scores for the Coffee brews. By multivariate analysis techniques, the samples were separated into groups according to production years indicating a strong influence of the environmental conditions on the chemical composition. The profile of the composition of the crude Coffee can be indicative of the sensory quality of the Coffee brews, relevant information for producers and industry since the green beans are the material used for trading and purchasing Coffee.
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support vector machines in tandem with infrared spectroscopy for geographical classification of green Arabica Coffee
Lwt - Food Science and Technology, 2017Co-Authors: Evandro Bona, Jade Varaschim Link, Andre Luis Guimaraes Lemes, Izabele Marquetti, Maria Brigida Dos Santos Scholz, Gustavo Yasuo Figueiredo Makimori, Vinicius Da Costa Arca, Juliana Mendes Garcia Ferreira, Patricia ValderramaAbstract:Abstract The Coffee is an important commodity to Brazil. Species, climate, genotypes, cultivation practices and industrialization are critical to final quality of the beverage. Thus, the development of analytical methods for Coffee authentication is important to ensure the origin of the bean. The purpose of this study was to develop a methodology for geographical classification of different genotypes of Arabica Coffee using infrared spectroscopy and support vector machines (SVM). The spectra were collected in the range of near infrared (NIRS) and mid infrared (FTIR). For the data analysis, a SVM was built using radial basis as kernel function and the one-versus-all multiclass approach. The C and γ parameters of SVM were optimized using the genetic algorithm. With the application of the NIRS-SVM approach all test samples were correctly classified with a sensitivity and specificity of 100%, while FTIR-SVM had a slightly lower performance. Therefore, it was possible to confirm that infrared spectroscopy is a fast and effective method for geographic certification with little sample preparation, and without the production of chemical wastes. Furthermore, the SVM can be a chemometric alternative in tandem with infrared spectroscopy for another classification problems.
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bioactive compounds content in roasted Coffee from traditional and modern coffea Arabica cultivars grown under the same edapho climatic conditions
Food Research International, 2014Co-Authors: Cintia Sorane Good Kitzberger, Maria Brigida Dos Santos Scholz, Marta De Toledo BenassiAbstract:Abstract Genetic improvement of Coffee is aimed at transferring disease resistance genes from Coffea canephora to Coffea Arabica cultivars, but the composition of Arabica Coffee could be affected by the introgression of genetic material from canephora. The objective of the this work was to compare traditional Brazilian Arabica Coffee cultivars (Bourbon, Catuai, and Icatu) with modern Arabica cultivars (IAPAR 59, IPR 98, IPR 99, and IPR 103) produced in the same edapho-climatic conditions. The cultivation, harvesting, post-harvesting and roasting processes were standardized to evaluate the influence of genetic diversity on the composition of bioactive compounds (5-caffeoylquinic acid, trigonelline, nicotinic acid, caffeine, cafestol, kahweol, and melanoidins) and antioxidant activity (AA) of the roasted Coffees. Compositional variability among the Coffee cultivars studied was observed, mainly with regard to contents of 5-caffeoylquinic acid (5-CQA) (from 936 to 1695 mg 100 g− 1), cafestol (from 414 to 742 mg 100 g− 1), and kahweol (from 439 to 1068 mg 100 g− 1). In general, Arabica cultivars with the introgression of C. canephora genes showed high antioxidant activity and differed from Coffees of traditional Arabica genotypes mainly in terms of their diterpenes profiles. A high correlation was observed among the AA (assessed by different methods) and some of the bioactive compounds (melanoidins, caffeine, and 5-CQA). Variability in the levels of the bioactive compounds was higher than that the observed for AA (from 4.2 to 4.7 g gallic acid 100 g− 1 by Folin–Ciocalteau reducing capacity, from 3.75 to 5. 42 g Trolox 100 g− 1 Coffee by ABTS radical scavenging activity, and from 80.1 to 83.0 percentage of inhibition of autoxidation of linoleic acid).
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geographical and genotypic segmentation of Arabica Coffee using self organizing maps
Food Research International, 2014Co-Authors: Jade Varaschim Link, Andre Luis Guimaraes Lemes, Izabele Marquetti, Maria Brigida Dos Santos Scholz, Evandro BonaAbstract:Several statistical methods have been developed in an attempt to reproduce the human capability of pattern recognition. Self-organizing maps (SOMs) are a type of artificial neural network (ANN) with unsupervised learning designed to examine the structure of multidimensional data. This study aimed to conduct a segmentation of the geographical and genotypic Coffee grown in the Coffee region of Parana — Brazil using the SOM for cluster analysis. Fourteen Arabica Coffee genotypes from two different cities were collected (Paranavai and Cornelio Procopio). Density, caffeine, chlorogenic acids, tannins, total and reducing sugars, proteins, and lipids of the green Coffee beans were analyzed. Using these data, the SOM was able to discriminate the 14 genotypes and also segmentation of the geographical origin was observed. Reducing sugars, caffeine, and chlorogenic acid were the most important variables for separation of the region of cultivation of Arabica Coffee genotypes. It was concluded that the SOM was able to recognize the Coffee genotypes and geographical origin using the chemical profile data.
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discrimination of Arabica Coffee cultivars by electrospray ionization fourier transform ion cyclotron resonance mass spectrometry and chemometrics
Web Science, 2013Co-Authors: Rafael Garrett, Maria Brigida Dos Santos Scholz, Cintia Sorane Good Kitzberger, Eduardo Morgado Schmidt, Luiz Filipe Protasio Pereira, Marcos N Eberlin, Claudia M RezendeAbstract:Abstract Green beans of Coffea Arabica (Arabica Coffee) cultivars with Sarchimor and Catuai genetic background were grown under the same edaphoclimatic conditions, in two different regions, and analysed by direct-infusion electrospray ionization Fourier transform ion cyclotron resonance mass spectrometry (ESI FT-ICR MS) followed by a metabolomic approach. A total of 20 Coffee metabolites including phenolic compounds, fatty acids, sucrose, and diterpene glycosides were identified by negative ESI FT-ICR MS with a mass error
Justin Moat - One of the best experts on this subject based on the ideXlab platform.
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least concern to endangered applying climate change projections profoundly influences the extinction risk assessment for wild Arabica Coffee
Global Change Biology, 2019Co-Authors: Justin Moat, Tadesse Woldemariam Gole, Aaron P DavisAbstract:Arabica Coffee (Coffea Arabica) is a key crop in many tropical countries and globally provides an export value of over US$13 billion per year. Wild Arabica Coffee is of fundamental importance for the global Coffee sector and of direct importance within Ethiopia, as a source of harvestable income and planting stock. Published studies show that climate change is projected to have a substantial negative influence on the current suitable growing areas for indigenous Arabica in Ethiopia and South Sudan. Here we use all available future projections for the species based on multiple general circulation models (GCMs), emission scenarios and migration scenarios, to predict changes in Extent of Occurrence (EOO), Area of Occupancy (AOO) and population numbers for wild Arabica Coffee. Under climate change alone, our results show that population numbers could reduce by 50% or more (with a few models showing over 80%) by 2088. EOO and AOO are projected to decline by around 30% in many cases. Furthermore, present-day models compared to the near future (2038), show a reduction for EOO of over 40% (with a few cases over 50%), although EOO should be treated with caution due to its sensitivity to outlying occurrences. When applying these metrics to extinction risk, we show that the determination of generation length is critical. When applying the International Union for Conservation of Nature’s Red list of Threatened Species (IUCN Red List) criteria, even with a very conservative generation length of 21 years, wild Arabica Coffee is assessed as Threatened with extinction (placed in the Endangered category) under a broad range of climate change projections, if no interventions are made. Importantly, if we do not include climate change in our assessment, Arabica Coffee is assessed as Least Concern (Non-threatened) when applying the IUCN Red List criteria
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the impact of climate change on indigenous Arabica Coffee coffea Arabica predicting future trends and identifying priorities
PLOS ONE, 2012Co-Authors: Aaron P Davis, Tadesse Woldemariam Gole, Susana Baena, Justin MoatAbstract:Precise modelling of the influence of climate change on Arabica Coffee is limited; there are no data available for indigenous populations of this species. In this study we model the present and future predicted distribution of indigenous Arabica, and identify priorities in order to facilitate appropriate decision making for conservation, monitoring and future research. Using distribution data we perform bioclimatic modelling and examine future distribution with the HadCM3 climate model for three emission scenarios (A1B, A2A, B2A) over three time intervals (2020, 2050, 2080). The models show a profoundly negative influence on indigenous Arabica. In a locality analysis the most favourable outcome is a c. 65% reduction in the number of pre-existing bioclimatically suitable localities, and at worst an almost 100% reduction, by 2080. In an area analysis the most favourable outcome is a 38% reduction in suitable bioclimatic space, and the least favourable a c. 90% reduction, by 2080. Based on known occurrences and ecological tolerances of Arabica, bioclimatic unsuitability would place populations in peril, leading to severe stress and a high risk of extinction. This study establishes a fundamental baseline for assessing the consequences of climate change on wild populations of Arabica Coffee. Specifically, it: (1) identifies and categorizes localities and areas that are predicted to be under threat from climate change now and in the short- to medium-term (2020–2050), representing assessment priorities for ex situ conservation; (2) identifies ‘core localities’ that could have the potential to withstand climate change until at least 2080, and therefore serve as long-term in situ storehouses for Coffee genetic resources; (3) provides the location and characterization of target locations (populations) for on-the-ground monitoring of climate change influence. Arabica Coffee is confimed as a climate sensitivite species, supporting data and inference that existing plantations will be neagtively impacted by climate change.
Gezahegn Berecha - One of the best experts on this subject based on the ideXlab platform.
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conserving wild Arabica Coffee emerging threats and opportunities
Agriculture Ecosystems & Environment, 2017Co-Authors: Raf Aerts, Gezahegn Berecha, Bart Muys, Lore Geeraert, Kitessa Hundera, Hanne De Kort, Olivier HonnayAbstract:Abstract Climate change and emerging pests and diseases are posing important challenges to global crop productivity, including that of Arabica Coffee. The genetic basis of commercially used Arabica Coffee cultivars is extremely narrow, and it is uncertain how much genetic diversity is present in ex situ collections. Conserving the wild Arabica Coffee gene pool and its evolutionary potential present in the montane forests of SW Ethiopia is thus critically important for maintaining Coffee yield and yield stability worldwide. Globally, Coffee agroforestry helps to conserve forest cover and forest biodiversity that cannot persist in open agricultural landscapes, but the conservation of the wild Arabica Coffee gene pool requires other priorities than those that are usually set for conserving forest biodiversity in mixed tropical landscapes. We show how forest loss and degradation, Coffee management, in particular production intensification, and the introduction of cultivars, are threatening the genetic integrity of these wild populations. We propose an active land sparing approach based on strict land use zoning to conserve the genetic resources and the in situ evolutionary potential of Arabica Coffee and discuss the major challenges including the development of access and benefit sharing mechanisms for ensuring long-term support to conservation.
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effects of forest management on mating patterns pollen flow and intergenerational transfer of genetic diversity in wild Arabica Coffee coffea Arabica l from afromontane rainforests
Biological Journal of The Linnean Society, 2014Co-Authors: Katrien Vandepitte, Sabine Van Glabeke, Gezahegn Berecha, Raf Aerts, Bart Muys, Isabel Roldanruiz, Olivier HonnayAbstract:Coffea Arabica, the wild ancestor of all commercial Arabica Coffee cultivars worldwide, is endemic to the montane rainforests of Ethiopia. These forests, which harbour the most important C. Arabica gene pool, are threatened by increasing anthropogenic disturbance, potentially altering the mating patterns, pollen dispersal and maintenance of genetic diversity in C. Arabica understorey populations. We genotyped 376 adult Coffee shrubs and 418 progenies from three natural unmanaged, and three highly managed Coffee populations, using 24 microsatellite markers. Mating system analysis of C. Arabica yielded an overall multilocus outcrossing rate of 76%, which contrasts with the common knowledge that C. Arabica is a predominantly selfing species. In highly managed Coffee populations, paternity could be assigned to 78% of the progenies, whereas in the unmanaged natural Coffee populations, only 57% of the progenies could be assigned to a father, indicating reduced long-distance pollen dispersal in managed forests. Furthermore, the fraction of selfed progenies was significantly higher in managed (23%) than unmanaged (10%) Coffee forests. Finally, the lack of spatial genetic structure in all studied populations suggests high seed dispersal in unmanaged populations, and intense berry harvesting and Coffee planting in the managed populations. Our results imply that in situ conservation of the wild gene pool of C. Arabica must focus on limiting intensification of Coffee forest management, as decreased pollen dispersal and increased selfing in C. Arabica in intensively managed populations may increase the risk of genetic erosion. © 2014 The Linnean Society of London, Biological Journal of the Linnean Society, 2014, 112, 76–88.