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1.
Acta amaz. ; 49(3): 173-178, July-Sept. 2019. ilus, mapas, tab, graf
Artigo em Inglês | VETINDEX | ID: vti-24126

RESUMO

Coffea canephora (Conilon coffee) has great economic importance for the state of Acre, in northern Brazil. The use of insecticides in this crop has increased considerably in recent years. In order to find species of green lacewing (Chrysopidae, Neuroptera) with potential for use in biological pest control in coffee plantations, we sampled green lacewings during one year in an experimental plantation of Conilon coffee in Acre, in order to assess the diversity, abundance and seasonal occurrence of Chrysopidae species. Samplings were carried out weekly using an entomological net. Overall, 1079 specimens of seven green lacewing species were collected: Ceraeochrysa cincta, Ceraeochrysa claveri, Ceraeochrysa cubana, Ceraeochrysa everes, Chrysoperla externa, Leucochrysa (Nodita) cruentata and Leucochrysa (Nodita) marquezi. Ceraeochrysa cubana was the dominant and constant species, comprising 97% of the sampled specimens and occurring in 82% of the weekly samples. The abundance and constant presence of C. cubana, which preys upon several agricultural pests and has shown resistance to various insecticides, make this species a potential candidate for future programs of biological control in Conilon coffee plantations in the southwestern Brazilian Amazon region.(AU)


Coffea canephora (café Conilon) tem grande importância econômica para o estado do Acre, porém o uso de inseticidas nessa cultura tem aumentado consideravelmente nos últimos anos. A fim de prospectar espécies de Chrysopidae (Neuroptera) com potencial para uso em programas de controle biológico de pragas dessa cultura, nós amostramos crisopídeos em um plantio experimental de café Conilon no Acre durante um ano, para avaliar a diversidade, abundância e ocorrência sazonal de espécies deste grupo de insetos. As amostragens foram semanais por meio do uso de rede entomológica. Foram coletados 1079 espécimes de sete espécies de crisopídeos: Ceraeochrysa cincta, Ceraeochrysa claveri, Ceraeochrysa cubana, Ceraeochrysa everes, Chrysoperla externa, Leucochrysa (Nodita) cruentata and Leucochrysa (Nodita) marquezi. Ceraeochrysa cubana foi a espécie mais dominante e constante, constituindo 97% dos exemplares coletados e ocorrendo em 82% das amostras. Esses resultados, somados ao fato de que C. cubana é predadora de diversas pragas agrícolas e possui resistência a vários inseticidas, indicam que essa espécie é candidata potencial para o uso em futuros programas de controle biológico de pragas de café Conilon no sudoeste da Amazônia brasileira.(AU)


Assuntos
Coffea/anatomia & histologia , Coffea/classificação , Biodiversidade , Rubiaceae , Inseticidas/efeitos adversos
2.
Genetica ; 147(2): 205-216, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-31054007

RESUMO

Information about population structure and genetic relationships within and among wild and brazilian Coffea arabica L. genotypes is highly relevant to optimize the use of genetic resources for breeding purposes. In this study, we evaluated genetic diversity, clustering analysis based on Jaccard's coefficient and population structure in 33 genotypes of C. arabica and of three diploid Coffea species (C. canephora, C. eugenioides and C. racemosa) using 30 SSR markers. A total of 206 alleles were identified, with a mean of 6.9 over all loci. The set of SSR markers was able to discriminate all genotypes and revealed that Ethiopian accessions presented higher genetic diversity than commercial varieties. Population structure analysis indicated two genetic groups, one corresponding to Ethiopian accessions and another corresponding predominantly to commercial cultivars. Thirty-four private alleles were detected in the group of accessions collected from West side of Great Rift Valley. We observed a lower average genetic distance of the C. arabica genotypes in relation to C. eugenioides than C. canephora. Interestingly, commercial cultivars were genetically closer to C. eugenioides than C. canephora and C. racemosa. The great allelic richness observed in Ethiopian Arabica coffee, especially in Western group showed that these accessions can be potential source of new alleles to be explored by coffee breeding programs.


Assuntos
Coffea/genética , Repetições de Microssatélites , Polimorfismo Genético , Coffea/classificação , Genótipo , Técnicas de Genotipagem/métodos , Técnicas de Genotipagem/normas , Filogenia , Melhoramento Vegetal/métodos
3.
Hig. Aliment. (Online) ; 33(288/289): 1229-1233, abr.-maio 2019. graf
Artigo em Português | LILACS, VETINDEX | ID: biblio-1482134

RESUMO

O agronegócio do café é uma das atividades que mais contribuem para economia brasileira. Objetivou-se avaliar a utilização da espectroscopia no infravermelho médio aliado a análise estatística multivariada para classificar amostras de café. As amostras foram adquiridas em Vitória da Conquista-Bahia e foram utilizadas para obtenção dos espectros no FTIR-ATR – Espectroscopia de Infravermelho com Transformada de Fourier com Reflexão Total Atenuada, sob a faixa espectral de 4000 a 600 cm(-1). Os resultados foram avaliados por meio da estatística multivariada Análise de Componentes Principais - ACP. Na ACP dois componentes explicaram 94,49% da variância total dos dados, onde o primeiro componente principal (CP1) explicou 82,1% e o segundo componente principal (CP2) 12,39%. É possível classificar amostras de café por meio destas ferramentas.


Assuntos
Análise Multivariada , Coffea/classificação , Coffea/química , Espectroscopia de Infravermelho com Transformada de Fourier , Análise de Componente Principal , Interpretação Estatística de Dados
4.
Hig. aliment ; 33(288/289): 1229-1233, abr.-maio 2019. graf
Artigo em Português | VETINDEX | ID: vti-23021

RESUMO

O agronegócio do café é uma das atividades que mais contribuem para economia brasileira. Objetivou-se avaliar a utilização da espectroscopia no infravermelho médio aliado a análise estatística multivariada para classificar amostras de café. As amostras foram adquiridas em Vitória da Conquista-Bahia e foram utilizadas para obtenção dos espectros no FTIR-ATR Espectroscopia de Infravermelho com Transformada de Fourier com Reflexão Total Atenuada, sob a faixa espectral de 4000 a 600 cm(-1). Os resultados foram avaliados por meio da estatística multivariada Análise de Componentes Principais - ACP. Na ACP dois componentes explicaram 94,49% da variância total dos dados, onde o primeiro componente principal (CP1) explicou 82,1% e o segundo componente principal (CP2) 12,39%. É possível classificar amostras de café por meio destas ferramentas.(AU)


Assuntos
Espectroscopia de Infravermelho com Transformada de Fourier , Análise Multivariada , Coffea/química , Coffea/classificação , Interpretação Estatística de Dados , Análise de Componente Principal
5.
Food Res Int ; 115: 227-233, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-30599935

RESUMO

To produce specific desirable coffee blends, Coffea arabica and C. canephora are mixed each other, in some cases to suit consumer preference, but in others to reduce production costs. In this scenario, the aim of this work was to evaluate standard candidate reference materials (RMc) for analysis of different blends of roasted and ground coffee. For this purpose, we analyzed different percentages of C. arabica and C. canephora (100:0; 50:50; 25:75; and 0:100, respectively). These RMc samples were developed in a previous study with green coffee beans submitted to medium roasting. In this work, coffee species differentiation (C. arabica and C. canephora) was analyzed by real-time PCR, using specific primers previously developed, called ARA primers. The RMc material with 100% C. canephora did not present amplification, in contrast with the samples containing C. arabica, which all presented amplification. These results indicate the specificity of ARA primers for C. arabica and that the detection system assay can be used as a promising molecular tool to identify and quantify percentages of C. arabica in different coffee blends.


Assuntos
Coffea/genética , Café/genética , Reação em Cadeia da Polimerase em Tempo Real/métodos , Sementes/genética , Coffea/química , Coffea/classificação , Café/química , DNA de Plantas/análise , DNA de Plantas/genética , Análise de Alimentos/métodos , Manipulação de Alimentos/métodos , Sementes/química , Sementes/classificação
6.
J Texture Stud ; 50(2): 172-184, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-30676645

RESUMO

When it comes to the sensory analysis of specialty coffees, it is necessary to discuss the protocol of tests of the Specialty Coffee Association (SCA) and the formation of Q-Graders as reliable parameters in the sensory analysis. However, the training of these Q-Graders and the use of the SCA protocol has generated discussions in the scientific community and demonstrated the importance of talking about the level of professional precision as well as the use of the protocol. This study sought to understand the relation of accuracy and efficiency of the Q-Graders and protocol in the sensory analysis of coffees. Three experiments were carried out to evaluate and test the hypotheses regarding the level of precision in relation to the shift, the number of samples and the judgment abilities of Q-Graders due to the quality of the specialty coffee and nonspecialty coffee. These three experiments were performed by seven Q-Graders in an isolated environment during three consecutive days with 137 specialty coffee samples and 7 nonspecialty coffee samples as defined by the SCA. The results indicate that the Q-Graders present high precision when evaluating excellent and outstanding coffees, as defined by the SCA. In addition, the effect of the shift did not exert fatigue on the Q-Graders. However, evaluation errors were made by the Q-Graders on very good coffee (77.00-80.00 points), which are considered as nonspecialty by the SCA, thus allowing a more in-depth discussion on what would be the boundary between a specialty and nonspecialty coffee. PRACTICAL APPLICATIONS: The article deals with the sensory evaluation process of coffees, and it has great importance to teaching and research institutions in Brazil, the largest producer, largest exporter and the country with the highest concentration of coffee scholars in the world. The article focuses on a new approach and a new way of looking at the sensory evaluation process of coffees, using the methodology of the Specialty Coffee Association to analyze the accuracy and efficiency of the Q-Graders.


Assuntos
Café/química , Análise de Alimentos/métodos , Qualidade dos Alimentos , Paladar , Brasil , Coffea/química , Coffea/classificação , Café/classificação , Humanos , Sementes
7.
ScientificWorldJournal ; 2017: 1248954, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29214204

RESUMO

Genetic resources of Coffea canephora have been introduced in several tropical countries with potential for crop development. In Ecuador, the species has been cultivated since the mid-20th century. However, little is known about the diversity and genetic structure of introduced germplasm. This paper provides an overview of the genetic and phenotypic diversity of C. canephora in Ecuador and some proposals for implementing a breeding program. Twelve SSR markers were used to analyze 1491 plants of C. canephora grown in different living collections in Ecuador, compared to 29 genotypes representing the main genetic and geographic diversity groups identified within the species. Results indicated that most of the genotypes introduced are of Congolese origin, with accessions from both main subgroups, SG1 and SG2. Some genotypes were classed as hybrids between both subgroups. Substantial phenotypic diversity was also found, and correlations were observed with genetic diversity. Ecuadorian Robusta coffee displays wide genetic diversity and we propose some ways of improving Robusta in Ecuador. A breeding program could be based on three operations: the choice of elite clones, the introduction of new material from other countries (Ivory Coast, Uganda), and the creation of new hybrid material using genotypes from the different diversity groups.


Assuntos
Biodiversidade , Cruzamento , Coffea/genética , Espécies Introduzidas , Coffea/classificação , Equador , Marcadores Genéticos , Variação Genética , Genótipo , Fenótipo , Filogenia
8.
BMC Plant Biol ; 16: 94, 2016 Apr 19.
Artigo em Inglês | MEDLINE | ID: mdl-27095276

RESUMO

BACKGROUND: Drought is a widespread limiting factor in coffee plants. It affects plant development, fruit production, bean development and consequently beverage quality. Genetic diversity for drought tolerance exists within the coffee genus. However, the molecular mechanisms underlying the adaptation of coffee plants to drought are largely unknown. In this study, we compared the molecular responses to drought in two commercial cultivars (IAPAR59, drought-tolerant and Rubi, drought-susceptible) of Coffea arabica grown in the field under control (irrigation) and drought conditions using the pyrosequencing of RNA extracted from shoot apices and analysing the expression of 38 candidate genes. RESULTS: Pyrosequencing from shoot apices generated a total of 34.7 Mbp and 535,544 reads enabling the identification of 43,087 clusters (41,512 contigs and 1,575 singletons). These data included 17,719 clusters (16,238 contigs and 1,575 singletons) exclusively from 454 sequencing reads, along with 25,368 hybrid clusters assembled with 454 sequences. The comparison of DNA libraries identified new candidate genes (n = 20) presenting differential expression between IAPAR59 and Rubi and/or drought conditions. Their expression was monitored in plagiotropic buds, together with those of other (n = 18) candidates genes. Under drought conditions, up-regulated expression was observed in IAPAR59 but not in Rubi for CaSTK1 (protein kinase), CaSAMT1 (SAM-dependent methyltransferase), CaSLP1 (plant development) and CaMAS1 (ABA biosynthesis). Interestingly, the expression of lipid-transfer protein (nsLTP) genes was also highly up-regulated under drought conditions in IAPAR59. This may have been related to the thicker cuticle observed on the abaxial leaf surface in IAPAR59 compared to Rubi. CONCLUSIONS: The full transcriptome assembly of C. arabica, followed by functional annotation, enabled us to identify differentially expressed genes related to drought conditions. Using these data, candidate genes were selected and their differential expression profiles were confirmed by qPCR experiments in plagiotropic buds of IAPAR59 and Rubi under drought conditions. As regards the genes up-regulated under drought conditions, specifically in the drought-tolerant IAPAR59, several corresponded to orphan genes but also to genes coding proteins involved in signal transduction pathways, as well as ABA and lipid metabolism, for example. The identification of these genes should help advance our understanding of the genetic determinism of drought tolerance in coffee.


Assuntos
Adaptação Fisiológica/genética , Coffea/genética , Secas , Genes de Plantas/genética , Sequenciamento de Nucleotídeos em Larga Escala/métodos , Brotos de Planta/genética , Coffea/classificação , Coffea/fisiologia , Café/genética , Café/fisiologia , Perfilação da Expressão Gênica/métodos , Regulação da Expressão Gênica de Plantas , Biblioteca Gênica , Ontologia Genética , Folhas de Planta/genética , Folhas de Planta/fisiologia , Brotos de Planta/fisiologia , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Especificidade da Espécie
9.
J Sci Food Agric ; 96(10): 3543-51, 2016 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-26592362

RESUMO

BACKGROUND: Knowledge of the sensory profile of coffee quality, associated with genetic and environmental factors, is of utmost importance for the international market, as well as for the productive sector. In this context, the goal of this study was to classify the quality of Coffea arabica L., cv. Yellow Bourbon, according to different scores obtained through sensory evaluations based on the Specialty Coffee Association of America protocol (SCAA), and by means of decision trees resulting from applying the CHAID method (chi-square automatic interaction detection). To that end, we used a database with the sensory characteristics of cv. Yellow Bourbon and the environmental characteristics of the Mantiqueira de Minas region, State of Minas Gerais, Brazil. RESULTS: The method used exhibited promising results regarding accuracy and success rates in order to discriminate coffee sensory quality as a function of the production environment. The results obtained clearly show the effect of the coffee growing environment on the Yellow Bourbon variety, resulting in notable sensory differences in the beverage. CONCLUSION: It was possible to discriminate cv. Yellow Bourbon coffee samples, the sensory evaluations of which resulted in scores of ≥88 points, which are associated with growing environments at altitudes of ≥1200 m. © 2015 Society of Chemical Industry.


Assuntos
Altitude , Coffea/química , Café/química , Brasil , Coffea/classificação , Árvores de Decisões , Olfato , Paladar
10.
J Sci Food Agric ; 96(9): 3098-108, 2016 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-26439192

RESUMO

BACKGROUND: Detailed knowledge of coffee production systems enables optimization of crop management, harvesting and post-harvest techniques. In this study, coffee quality is mapped as a function of coffee variety, altitude and terrain aspect attributes. The work was performed in the Zona da Mata, Minas Gerais, Brazil. RESULTS: A large range of coffee quality grades was observed for the Red Catuai variety. For the Yellow Catuai variety, no quality grades lower than 70 were observed. Regarding the terrain aspect, samples from the southeast-facing slope (SEFS) and the northwest-facing slope (NWFS) exhibited distinct behaviors. The SEFS samples had a greater range of quality grades than did the NWFS samples. The highest grade was obtained from an NWFS point. The lowest quality values and the largest range of grades were observed at lower altitudes. The extracts from the highest-altitude samples did not produce any low-quality coffee. CONCLUSIONS: The production site's position and altitude are the primary variables that influenced the coffee quality. The study area has micro-regions with grades ranging from 80 to 94. These areas have the potential for producing specialty coffees. © 2015 Society of Chemical Industry.


Assuntos
Bebidas/normas , Coffea/anatomia & histologia , Café/normas , Agricultura/métodos , Altitude , Análise de Variância , Bebidas/análise , Brasil , Coffea/química , Coffea/classificação , Café/química , Café/classificação , Qualidade dos Alimentos , Mapeamento Geográfico , Controle de Qualidade , Paladar
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