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Coffee seeds are classified as intermediate because they have low tolerance to desiccation and low longevity. Consequently, moisture control and storage conditions are important factors in maintaining the physiological quality of these seeds. Thus, the objective in this work was to evaluate the water content effect on coffee seed longevity. Seeds of five Coffea arabica cultivars from the 2016/2017 crop were used. Part of the harvested seeds was dried in the shade until reach 12% moisture and the other part did not go through drying process, remaining with 40% water content. The seeds were stored in a cold chamber at 10 oC for a period of nine months, and the physiological quality was evaluated every three months by germination, root protrusion, seedlings with expanded cotyledonary leaves, seedling dry mass and enzymatic analysis of catalase enzymes and superoxide dismutase. Regardless of the cultivar, wet seeds coffee storage provides better maintenance of physiological quality for up to nine months. Seedling vigor is reduced throughout the storage period, regardless of seed water content. Made available in DSpace on 2021-06-16T02:20:43Z (GMT). No. of bitstreams: 1 Penido-et-al-Cold-coffee-seeds-storage-with-different-water-content.pdf: 1707728 bytes, checksum: e02efe7c1b6d1bcd01015c9c6a91f6d6 (MD5) Previous issue date: 2021

Coffee is among the most significant products in Brazil. Minas Gerais is the largest state producer of Arabica coffee. Coffee activity has excellent growth potential, which justifies the identification of new areas for expansion of the culture. This study aimed to determine factors that affect the spatial distribution of coffee plantations the most, as well as to identify areas with a greater aptitude for its expansion in the region of the Matas de Minas (63 municipalities). The MaxEnt software was used to elaborate a model capable of describing the area with the highest potential for estimating the probability of coffee adequacy. The elaboration of the model considered the records of occurrence, climatic and topographic variables of Matas de Minas, the second largest state producing region. The area under the curve (AUC), the omission rate and the Jackknife test were used for validation and analysis of the model. The model was accurate with an AUC of 0.816 and omission rate of 0.54% for the ‘test’. It was identified that the potential distribution of coffee in Matas de Minas is determined by changes in the annual maximum temperature, although it did not generate a significant gain when omitted, accounting for a considerable loss in the model. However, the most influential variables on the delineation of distribution were, the altitude and the annual average temperature. The most favorable areas for expansion of coffee culture in the Matas de Minas were found in the vicinity of the region of Alto Caparaó.Abbreviations used: A1 (altitude); A2 (maximum annual temperature); A3 (annual minimum temperature); BIO 1 (annual average temperature 1); BIO 4 (temperature seasonality), BIO 12 (annual precipitation); BIO 15 (precipitation seasonality); csv (comma-separated values); AUC (area under the curve). Coffee is among the most significant products in Brazil. Minas Gerais is the largest state producer of Arabica coffee. Coffee activity has excellent growth potential, which justifies the identification of new areas for expansion of the culture. This study aimed to determine factors that affect the spatial distribution of coffee plantations the most, as well as to identify areas with a greater aptitude for its expansion in the region of the Matas de Minas (63 municipalities). The MaxEnt software was used to elaborate a model capable of describing the area with the highest potential for estimating the probability of coffee adequacy. The elaboration of the model considered the records of occurrence, climatic and topographic variables of Matas de Minas, the second largest state producing region. The area under the curve (AUC), the omission rate and the Jackknife test were used for validation and analysis of the model. The model was accurate with an AUC of 0.816 and omission rate of 0.54% for the ‘test’. It was identified that the potential distribution of coffee in Matas de Minas is determined by changes in the annual maximum temperature, although it did not generate a significant gain when omitted, accounting for a considerable loss in the model. However, the most influential variables on the delineation of distribution were, the altitude and the annual average temperature. The most favorable areas for expansion of coffee culture in the Matas de Minas were found in the vicinity of the region of Alto Caparaó.Abbreviations used: A1 (altitude); A2 (maximum annual temperature); A3 (annual minimum temperature); BIO 1 (annual average temperature 1); BIO 4 (temperature seasonality), BIO 12 (annual precipitation); BIO 15 (precipitation seasonality); csv (comma-separated values); AUC (area under the curve).

Coffee production has a great socioeconomic importance for Brazil. It generates direct and indirect jobs, and foreign exchange, with Brazilian Arabica coffee production estimated between 42 - 46 million bags (60 kg) in 2020. It is the main agribusiness activity in the State of Espírito Santo, Brazil with expected production between 13 - 15 million bags, and around 30% of this production is Arabica coffee. Technologies are recommended to coffee growers to increase yield, and production of specialty coffees on sustainable properties. Among the principles of integrated management is the monitoring of pests and diseases to determine the level of pest control. The estimate of the number of leaves to be sampled in the monitoring becomes an important tool to increase the accuracy of the obtained information. This research was carried out aiming to determine the minimum number of leaves necessary to evaluate the infestation of brown eye spot (BES) of coffee in Arabica coffee (Coffea arabica L.) without affecting the accuracy of the collection method. It was observed that the estimate of the minimum number for sampling was 46 leaves for the characteristics of incidence, and severity of BES in Arabica coffee. The modeling applied in this study allows to conclude that it is possible to recommend an optimum number of Arabica coffee leaves for these edaphoclimatic conditions, and variety, and it can serve as a basis for monitoring in an integrated pest and disease management program in Arabica coffee. Made available in DSpace on 2022-05-09T14:13:17Z (GMT). No. of bitstreams: 1 Modeling-the-brown-eye-spot-sampling-in-Arabica-coffee.pdf: 241284 bytes, checksum: d2f7324311c768536baf073020d3289d (MD5) Previous issue date: 2022

The bienniality of production and the incidence of pests and diseases, such as coffee leaf miner and coffee leaf rust, stands out among the factors that limit coffee crop yield. Obtaining cultivars with greater stability in production and resistance to these biotic agents are among the main objectives of coffee breeding programs. In this way, biotechnological tools such as Genomic Wide Association Studies (GWAS) can increase these programs' efficacy since they allow the identification of molecular markers significantly associated with phenotypes of interest. In this context, the aim here is to identify genomic regions associated with yield, bienniality, and resistance to coffee leaf miner and coffee leaf rust in arabica coffee progenies. Thus, a population (n=597) was evaluated for resistance to biotic stresses and for the eight designed scenarios to study yield and bienniality. A matrix of 4,666 SNPs (Single Nucleotide Polymorphism) was built through Genotyping by Sequencing (GBS). After the genomic association analyses, we identified 12 potential SNPs markers associated with resistance to coffee leaf miner and coffee leaf rust, 32 associated with the eight designed scenarios to study yield and bienniality. Of the 44 SNPs significantly associated with this study's traits, 36 were noted in genomic regions responsible for biological processes related to plant response to biotic and abiotic stresses. In addition, four markers were coincident with yield and traits related to coffee leaf rust resistance. The genomic regions identified in this study can be incorporated into the coffee breeding program, through assisted selection, leading to more efficient breeding strategies in coffee. Made available in DSpace on 2022-01-19T01:57:04Z (GMT). No. of bitstreams: 1 Association-mapping-reveals-genomic.pdf: 4980072 bytes, checksum: 34399cb2ad7148a41da800f9c630e3bc (MD5) Previous issue date: 2021

Plant breeding aims to develop cultivars with good agronomic traits through gene recombination and elite genotype selection. To support Coffea arabica breeding programs and assist parent selection, molecular characterization, genetic diversity (GD) analyses, and circulating diallel studies were strategically integrated to develop new cultivars. Molecular markers were used to assess the GD of 76 candidate parents and verify the crossing of potential F1 hybrids. Based on the complementary agronomic traits and genetic distance, eight elite parents were selected for circulating diallel analysis. The parents and 12 hybrids were evaluated based on 10 morpho-agronomic traits. For each trait, the effects of general and specific combining abilities, as well as the averages of the parents, hybrids, and predicted hybrids, were estimated. Crosses that maximize the genetic gains for the main agronomic traits of C. arabica were identified. Joint analysis of phenotypic and molecular data was used to estimate the correlation between molecular GD, phenotypic diversity (PD), phenotypic mean, and combining ability. The selection of parents that optimize the allele combination for the important traits of C. arabica is discussed in detail. Made available in DSpace on 2022-01-27T01:58:47Z (GMT). No. of bitstreams: 1 Combining-Ability-and-Molecular.pdf: 2421339 bytes, checksum: b1fd8d047ff3e47af308c96d0c676428 (MD5) Previous issue date: 2021

Post-harvest processing (PHP) modifies the quality of the coffee and increases the value of coffee production. The choice of PHP to apply depends primarily on the available infrastructure, local climatic conditions and the desired end-value. The objective of this study was to evaluate the influence of PHP on the physico-chemical characteristics of green and roasted coffee beans and their sensory attributes. Coffee cherries from IAPAR 59 cultivar were processed as natural coffee (CN), semi-dry coffee (CD), de-pulped coffee (CP) and floating coffee (CF). Total and reducing sugars, phenolic compounds, chlorogenic acids, lipids, proteins, caffeine and water content were determined in coffee beans collected during (10thday) and at the end of each processing. The roasted beans and their sensory attributes were also analyzed. The greatest changes at the ending point of the processes were found in total and reducing sugars, phenolic compounds, chlorogenic acids and lipids contents. The PHP presented different weight loss to achieve the same visual brown color and luminosity. Beverage sensory attributes were influenced by the PHP: CN and CP coffees presented similar intensities of coffee aroma, but higher intensity of green grassy aroma, and taste were found in CF and CN coffees. Aroma and taste precursors were modified during the PHP and these were associated to husk removal of the coffee beans, suggesting an activation of the germination metabolism during the PHP. This study allowed the characterization of the effects of the different post-harvest processing on the roasted coffee beans and provides the foundations to monitor their efficiencies in the future. Made available in DSpace on 2022-01-25T14:00:42Z (GMT). No. of bitstreams: 1 Flavor-precursors-and-sensory-attributes.pdf: 573175 bytes, checksum: 368650d928db2098f3cb1c6ea8173d83 (MD5) Previous issue date: 2020

Seed deterioration induces the formation of free radicals and proliferation of microorganisms, but the application of external antioxidants may lessen these effects. The aim of this study was to investigate the antioxidant and antimicrobial activity of cathode and anode water on the physiological quality and health of Coffea arabica L. seeds. Part of the seeds were soaked in cathode water and the other part in anode water for periods of 1, 6, 12, 24, and 36 hours. The physiological quality of the seeds was evaluated by the germination test and tetrazolium test, and seed health by the Blotter test. Analysis of variance and Pearson correlation analysis were performed on the data for all the response variables. Soaking in cathode water or anode water up to 24 hours improves the physiological quality of coffee seeds. Anode water has a beneficial effect on the health of coffee seeds, reducing the incidence of Fusarium spp., Penicillium spp., Cladosporium spp., and Alternaria spp. after one hour of soaking and of Aspergillus spp. after six hours. Soaking in cathode water for a period of one hour leads to a reduction in the fungi Aspergillus spp., Fusarium spp., Cladosporium spp., and Alternaria spp., and reduction in Penicillium spp. after six hours. Made available in DSpace on 2021-06-16T02:21:00Z (GMT). No. of bitstreams: 1 Vilela-et-al.-2021-Antioxidant-and-antimicrobial-activity-of-cathode-and-anode.pdf: 501480 bytes, checksum: 8637b101bfdcf73571d6a72d756d8840 (MD5) Previous issue date: 2021

Modelling studies on climate change predict continuous increases in atmospheric carbon dioxide concentration [CO2] and increase in temperature. This may alter carbon-based phytochemicals such phenolics and modify plant interactions with herbivorous. We investigated the effects of enhanced [CO2] and local climatic variation on young coffee plants, Coffea arabica L. cv Catuaí vermelho IAC-144 and Obatã vermelho IAC-1669-20, cultivated in the FACE (Free-Air Carbon Dioxide Enrichment) facility under two atmospheric [CO2] conditions. Coffee leaves were evaluated for total soluble phenolics (TSP), chlorogenic (5-CQA) and caffeic (CAF) acids, diversity and population size of mites, along two dry and two rainy seasons. Elevated atmospheric CO2 (e[CO2]) significantly decreased 5-CQA in cv. Catuaí but did not affect cv. Obatã. Species richness and population size of mites in coffee leaves were not affected by e[CO2] but were strongly related to the seasonal variability of coffee leaf phenolics. In general, high levels of phenolics were negatively correlated with population size while the mite species richness were negatively correlated with 5-CQA and TSP levels. Our fi ndings show that [CO2] enhancement affects phenolics in coffee plants differentially by cultivars, however seasonality is the key determinant of phenolics composition, mite species richness and population size. Made available in DSpace on 2021-08-13T18:00:52Z (GMT). No. of bitstreams: 1 Batista-Increased-atmospheric-2021.pdf: 317884 bytes, checksum: 93c6e82730273ff17f9275e61a843a56 (MD5) Previous issue date: 2021

The biotrophic fungus Hemileia vastatrix causes coffee leaf rust (CLR), one of the most devastating diseases in Coffea arabica . Coffee, like other plants, has developed effective mechanisms to recognize and respond to infections caused by pathogens. Plant resistance gene analogs (RGAs) have been identified in certain plants as candidates for resistance ( R ) genes or membrane receptors that activate the R genes. The RGAs identified in different plants possess conserved domains that play specific roles in the fight against pathogens. Despite the importance of RGAs, in coffee plants these genes and other molecular mechanisms of disease resistance are still unknown. This study aimed to sequence and characterize candidate genes from coffee plants with the potential for involvement in resistance to H. vastatrix . Sequencing was performed based on a library of bacterial artificial chromosomes (BAC) of the coffee clone ?Híbrido de Timor? (HdT) CIFC 832/2 and screened using a functional marker. Two RGAs, HdT_LRR_RLK1 and HdT_LRR_RLK2, containing the motif of leucine-rich repeat-like kinase (LRR-RLK) were identified. Based on the presence or absence of the HdT_LRR_RLK2 RGA in a number of differential coffee clones containing different combinations of the rust resistance gene, these RGAs did not correspond to any resistance gene already characterized (SH1-9). These genes were also analyzed using qPCR and demonstrated a major expression peak at 24 h after inoculation in both the compatible and incompatible interactions between coffee and H. vastatrix . These results are valuable information for breeding programs aimed at developing CLR-resistant cultivars, in addition to enabling a better understanding of the interactions between coffee and H. vastatrix. Made available in DSpace on 2022-01-26T14:00:41Z (GMT). No. of bitstreams: 1 receptor-like-kinase.pdf: 797260 bytes, checksum: 18841c8c3f9b08408ff2d898ecc48880 (MD5) Previous issue date: 2021

The identification of morphophysiological traits responsible for a better plant behavior when infected is useful for cultivar selection, and become crucial for breeding. We investigated the morphophysiological behavior of coffee genotypes before and after inoculation with the pathogen Hemileia vastatrix, causal agent of coffee rust. With multivariate techniques we identified the characteristics that most contribute to total genetic divergence of the genotypes. Ten genotypes of Coffea arabica from the Germplasm Bank of Coffee from Minas Gerais were sown in a nursery and then take to a greenhouse with controlled temperature and humidity. After one month of acclimatization, the artificial inoculation with the fungus H. vastatrix was carried out. The anatomical and physiological evaluations were performed 1 day before inoculation and 160 days after inoculation. When the first symptom emerged, plants were evaluated according to a descriptive scale for coffee rust. We observed significant differences in rust severity and ostiole opening between genotypes. Different groups were formed by the K-means method, based on morphophysiological characteristics. This shows that genetic variability exists between the coffee genotypes evaluated before and after inoculation with the pathogen. The most important characteristics that contributed to the total genetic divergence were xylem vessel diameter and stomatal conductance. In conclusion, inoculation with H. vastatrix caused a change in coffee genotypes based on morphophysiological characteristics. Made available in DSpace on 2022-05-24T05:03:25Z (GMT). No. of bitstreams: 1 Coffee-genotypes-morphophysiological.pdf: 967489 bytes, checksum: 301cd2748b8fec6b33967ca79bb735fb (MD5) Previous issue date: 2021

The aim of this study was to identify the correlation between photochemical efficiency and candidate genes expression to elucidate the drought tolerance mechanisms in coffee progenies (Icatu Vermelho IAC 3851-2 x Catimor UFV 1602-215) previously identified as tolerant in field conditions. Four progenies (2, 5, 12 and 15) were evaluated under water-deficit conditions (water deficit imposed 8 months after transplanting seedlings to the pots) and under irrigated system. Evaluations of physiological parameters and expression of candidate genes for drought tolerance were performed. Progeny 5 showed capacity to maintain water potential, which contributed to lower qP variation between irrigated and deficit conditions. However, the increases of qN and NPQ in response to stress indicate that this progeny is photochemically responsive to small variations of am protecting the photosystem and maintaining qP. Data obtained for progeny 12 indicated a lower water status maintenance capacity, but with increased qN and NPQ providing maintenance of the PSII and ETR parameters. A PCA analysis revealed that the genes coding regulatory proteins, ABA-synthesis, cellular protectors, isoforms of ascorbate peroxidase clearly displayed a major response to drought stress and discriminated the progenies 5 and 12 which showed a better photochemical response. The genes CaMYB1, CaERF017, CaEDR2, CaNCED, CaAPX1, CaAPX5, CaGolS3, CaDHN1 and CaPYL8a were up-regulated in the arabica coffee progenies with greater photochemical efficiency under deficit and therefore contributing to efficiency of the photosynthesis in drought tolerant progenies Made available in DSpace on 2021-07-20T15:01:13Z (GMT). No. of bitstreams: 1 Photochemical-efciency-correlated.pdf: 1599792 bytes, checksum: 8fcd09d5ca7177dd144b3a900116a490 (MD5) Previous issue date: 2021

Cryopreservation is a technique that may potentially conserve the germplasm of species of the Coffea genus for an indeterminate time. The aim of this study was to evaluate the physiological, biochemical and ultrastructural characteristics of cryopreserved seeds of Coffea arabica L., cultivar Catucaí amarelo IAC 62, which was subjected to different protocols regarding dehydration, precooling, cooling, rewarming and cathode water use. According to each protocol, the seeds were subjected to fast or slow drying to moisture contents of 17 or 20% (wet basis), cooled in different ways, and then immersed in liquid nitrogen for 24 hours. Different rewarming times in a water bath were also used. Physiological, biochemical and ultrastructural analyses were performed on the seeds after the cryopreservation steps. Moisture content at a 17% wb is the key factor for the cryopreservation of Coffea arabica L. seeds, which have better physiological quality and better preserved cell structures. Precooling of coffee seeds before immersion in liquid nitrogen does not provide advantages compared to direct immersion. The rewarming times tested (2, 4, and 6 minutes) and cathode water use did not cause changes in the physiological and biochemical quality or in the cell structures of Coffea arabica L. cryopreserved seeds. The pattern of cell structure observed in all seeds indicates that the damage from cryopreservation is less drastic in the cells of the embryos than in those of the endosperm, with the latter less tolerant to the stresses of dehydration, precooling, and rewarming. RESUMO A criopreservação é uma técnica que pode potencialmente conservar o germoplasma de espécies do gênero Coffea por tempo indeterminado. O objetivo neste estudo foi avaliar os aspectos fisiológicos, bioquímicos e ultraestruturais de sementes criopreservadas de Coffea arabica L., cultivar Catuaí amarelo IAC 62, submetidas a diferentes protocolos de desidratação, pré-resfriamento, resfriamento, reaquecimento e uso de água catódica. De acordo com cada protocolo as sementes foram submetidas à secagem rápida ou lenta, até 17 ou 20% de umidade (base úmida), resfriadas por diferentes maneiras e, em seguida, foram imersas em nitrogênio líquido por 24 horas. Diferentes tempos de reaquecimento em banho-maria também foram utilizados. Análises fisiológicas, bioquímicas e ultra-estruturais foram realizadas nas sementes após as etapas de criopreservação. O teor de umidade a 17% bu é o fator chave para a criopreservação de Coffea arabica L., umidade em que as sementes apresentam melhor qualidade fisiológica e estruturas celulares mais preservadas. O pré-resfriamento das sementes de café antes da imersão em nitrogênio líquido é dispensado por não apresentar vantagens em relação à imersão direta. Os tempos de reaquecimento testados (2, 4 e 6 minutos) e o uso de água catódica não causam alterações na qualidade fisiológica e bioquímica, bem como nas estruturas celulares das sementes criopreservadas de Coffea arabica L. O padrão de estrutura celular observado em todas as sementes indica que o dano da criopreservação é menos drástico nas células dos embriões do que nos endospermas, sendo este último menos tolerante aos estresses de desidratação, pré-resfriamento e reaquecimento.

Several factors such as genotype, environment, and post-harvest processing can affect the responses of important traits in the coffee production chain. Determining the influence of these factors is of great relevance, as they can be indicators of the characteristics of the coffee produced. The most efficient models choice to be applied should take into account the variety of information and the particularities of each biological material. This study was developed to evaluate statistical and machine learning models that would better discriminate environments through multi-traits of coffee genotypes and identify the main agronomic and beverage quality traits responsible for the variation of the environments. For that, 31 morpho-agronomic and post-harvest traits were evaluated, from field experiments installed in three municipalities in the Matas de Minas region, in the State of Minas Gerais, Brazil. Two types of post-harvest processing were evaluated: natural and pulped. The apparent error rate was estimated for each method. The Multilayer Perceptron and Radial Basis Function networks were able to discriminate the coffee samples in multi-environment more efficiently than the other methods, identifying differences in multi-traits responses according to the production sites and type of post-harvest processing. The local factors did not present specific traits that favored the severity of diseases and differentiated vegetative vigor. Sensory traits acidity and fragrance/aroma score also made little contribution to the discrimination process, indicating that acidity and fragrance/aroma are characteristic of coffee produced and all coffee samples evaluated are of the special type in the Mata of Minas region. The main traits responsible for the differentiation of production sites are plant height, fruit size, and bean production. The sensory trait "Body" is the main one to discriminate the form of post-harvest processing. Made available in DSpace on 2021-08-19T16:00:42Z (GMT). No. of bitstreams: 1 Machine-learning-and-statistics-to-qualify.pdf: 1998081 bytes, checksum: 5f8d40d907a02f2c08263f8c00f4cb1e (MD5) Previous issue date: 2021

Since its recent establishment in Hawaii, the coffee berry borer (CBB), Hypothenemus hampei (Coleoptera: Curculionidae), threatens yields, quality, and price of coffee production. A limited number of insecticides (primarily Beauveria bassiana) are used to control CBB with minimal disruption in this agroecosystem. We evaluated two insecticide spray strategies across eight coffee farms in the Kona and Ka?u districts of Hawaii Island. Coffee growers sprayed insecticides approximately monthly (calendar basis) or else in response to CBB field monitoring data (threshold based). Overall, farms adopting spray thresholds performed more insecticide applications early in the season (May to July), but significantly fewer overall, when compared with calendar-based strategies (i.e., 4?5 vs. 7?11 seasonal sprays, respectively). Generalized linear models assessing the variability in CBB infestation rates, berry penetration, and infection by B. bassiana indicated that threshold-based sprays provided equivalent CBB control compared with calendar ones. When corrected for yield, there were economic savings for threshold- vs. calendar-based spray programs (i.e., cost 5.4 vs. 11.8% of gross yield). Total defects in processed coffee after harvest were statistically similar between the two spray regimes, i.e., 8.5 ± 1.0% and 10.4 ± 1.7%, respectively. We hypothesize that B. bassiana applied early in the season is more effective, since the fungus targets initial CBB infestations when the prolonged location of founder females in the outer berry endosperm favors its infection. Our study suggests that spray timing for CBB based on field monitoring data can reduce costs; however, additional measures, such as field and post-harvest sanitation, are necessary to achieve sustainable CBB control in the Islands. Made available in DSpace on 2020-10-09T09:12:51Z (GMT). No. of bitstreams: 1 Mascarin-Incorporating-Beauveria-2020.pdf: 3521149 bytes, checksum: 6bdeec4e88abbf31da8f1e59015c37f0 (MD5) Previous issue date: 2020

The growing demand for alternative strategies for plant disease management has sought a reduction in the use of fungicides via the employment of resistance inducers and foliar fertilizers, among others. Therefore, this study aimed at evaluating the following foliar fertilizers for the management of phoma leaf spot: a foliar fertilizer based on macro-and micronutrients (Fmm: 10% N, 4% S, B, 5% Fe and 5% Zn); one based on cobalt and molybdenum (Fcm: 2% Co and 3% Mo); manganese phosphite (FMn: 30% P2O5 and 9% Mn); and the FMn+Fmm, Fcm+Fmm and FMn+Fcm+Fmm associations compared to a boscalid fungicide and a control with no treatment. The disease severity, the chlorophyll a and b contents, the net photosynthetic rate (LPR), the phenylalanine ammonia lyase (PAL) activity and the lignin content in leaves were assessment. Based on the severity, the area under the disease severity progress curve (AUSPC) and the efficiency of disease control in relation to untreated plants were calculated. The experimental design was in randomized blocks with eight treatments and three replications. Treatments FMn+Fmm and Fcm were the most effective in reducing the AUPSC in comparison with the control and promoted an increased activity of PAL. FMn was the treatment that promoted the highest increase in the LPR. There were no effects of the treatments on the lignin content compared to the control. Made available in DSpace on 2019-02-06T23:36:30Z (GMT). No. of bitstreams: 1 Pedro2018.pdf: 967520 bytes, checksum: 1c4e1a572068c0bebb808e691a10457f (MD5) Previous issue date: 2018-11-28

The endosperm of coffee beans is an important structure which is composed of different reserve compounds. In the present work, we followed anatomical features during the reserve mobilization of Coffea Arabica L. 'Catuaí' seed samples, harvested at 20 different sites, after 0, 3, 6, 12, 24, 33 and 45 days of imbibition. Seed samples were properly fixed and stored, respectively, for histochemical and enzyme activity approach. Fixed samples were cross-sectioned for detection of starch, lipids, essential oils, oleoresins, proteins, phenolic compounds, neutral polysaccharides, alkaloids, B-1,3 and B-1,4 glucans, and lignin. Overall, based on histochemical tests and enzyme activity, seed reserve mobilization was similar among the evaluated altitudes and mountainsides. During soaking, there is an intense consumption of reserve compounds, starting at the region close to the embryo. Reserve mobilization intensifies after root protrusion, from 12 days of soaking. The intensification of the reserve consumption is concomitant with an increased activity of MDH is observed at the first 12 days, whereas SOD showed higher expression after 33 days of soaking. At the 33 rd day, little reserve is observed in the endosperm. At 45th day, cotyledon leaves are expanded, and the root system, constituted by the taproot and lateral roots, is well established. Made available in DSpace on 2022-01-18T15:00:26Z (GMT). No. of bitstreams: 1 histochemical-approach-of-the-mobilization.pdf: 1296210 bytes, checksum: 24fa1e291a7c6bc7ccfced5a7116e0df (MD5) Previous issue date: 2020

The demand for high-quality coffee among consumers has generated a great deal of interest among producers in serving this market. Parameters for physiological analyses that can be associated with aspects of sensory analyses of coffee can ensure more reliable results for coffee quality assessments. The aim of this study was to investigate the potential of physiological analyses in determining coffee quality through multivariate analysis. Several samples from coffee bean/seed lots were placed in cold storage at 10 °C, after which the sensory quality, physiological quality, and chemical characteristics of the beans were evaluated before storage and after three and six months of storage. The variables of physiological quality in the coffee beans were correlated with sensory analysis parameters. The viability of coffee embryos revealed by the tetrazolium test results were positively correlated with the final sensory analysis score. There was a correlation of root dry matter, hypocotyl dry matter, potassium leaching, and electrical conductivity with the sensory attributes that comprise the final sensory analysis score for the coffee beans. Variation in the final sensory analysis score was explained up to 97.14% by the variables radical emergence (r2 = 2.27%), strong normal seedlings, (r2 = 0.56%), seedlings with expanded cotyledonary leaves (r2 = 0.53%), tetrazolium test results (r2 = 91.54%), and potassium leaching (r2 = 2.24%). More studies are required to enable the use of physiological analyses to complement sensory analysis. RESUMO A demanda por cafés com alta qualidade pelos consumidores tem gerado um grande interesse dos produtores em atender esse mercado. Análises fisiológicas que podem ser associadas com a análise sensorial do café podem garantir resultados mais confiáveis para a avaliação da qualidade do café. Objetivou-se com o estudo investigar o potencial de utilização das análises fisiológicas na determinação da qualidade do café, por meio da aplicação de análises multivariadas. Lotes de grãos de café foram colocados sob armazenamento em câmara a 10 ºC, e então foram realizadas avaliações da qualidade sensorial e fisiológica e das características químicas dos grãos antes do armazenamento e após três e seis meses de armazenamento. As variáveis de qualidade fisiológica dos grãos de café foram correlacionadas com a análise sensorial da bebida. A viabilidade dos embriões de café analisada pelo teste de tetrazólio foi positivamente correlacionada com a nota final da análise sensorial. Há correlação da matéria seca das raízes, matéria seca do hipocótilo, lixiviação de potássio e condutividade elétrica com os atributos sensoriais que compõem a nota final da análise sensorial dos grãos de café. 97,14% da variação da nota final da análise sensorial foi explicada pelas variáveis de emergência radicular (r2 = 2.27%), plântulas normais fortes (r2 = 0.56%), plântulas com folhas cotiledonares expandidas (r2 = 0.53%), teste de tetrazólio (r2 = 91.54%) e lixiviação de potássio (r2 = 2.24%). Mais estudos são necessários para permitir o uso das análises fisiológicas para complementar a análise sensorial da bebida.

During drying and freezing, protective mechanisms act to maintain seed physiological quality. Some of these mechanisms contribute to the integrity of cell membranes. The damage caused to cell membranes due to cell stress can be seen in ultrastructural studies. The aim of this study was to investigate ultrastructural changes in endosperm cells of coffee seeds brought about by drying and by exposure to low temperatures. Seeds of Coffea Arabica were dried in silica gel to moisture contents of 40, 20, and 5 % (wb) and brought to equilibrium at temperatures of 10, -20, and -86oC. Germination, vigor, and tetrazolium tests were performed for evaluation of seed physiological quality. Ultrastructural damage was analyzed by scanning electron microscopy. Coffee seeds with 40% moisture content have whole, swollen, and expanded cells, with a filled lumen and without signs of damage. The physiological and ultrastructural quality of seeds exposed to below zero temperatures with 40% moisture content is compromised. They have null germination and empty cells, indicating leakage of cell content. Drying of coffee seeds leads to uniform contraction of inner cell content. Drying of coffee seeds to 5% moisture content leads to intense contraction of cell volume, with physiological and ultrastructural damage. Made available in DSpace on 2022-01-18T16:00:40Z (GMT). No. of bitstreams: 1 Ultrastructural-damage-in-coffee-seeds.pdf: 2841205 bytes, checksum: f6e1825a4a770de6f6741d98678d1658 (MD5) Previous issue date: 2020

The weed control in coffee plants has great importance, as they compete for light, water and nutrients. The chemical control is the most used, emphasizing the glyphosate, however, when applied, drift can occur and consequently cause injuries to coffee. Many farmers use the sucrose application with the objective to reverse the damage caused by the herbicide drift, even without scientific basis to justify such action. The objective of this study was to evaluate the effect of the sucrose application on the detoxification of coffee plants in the implantation phase with glyphosate drift. The experiment was carried out in a greenhouse, using a randomized block design, arranged in a 3 x 3 factorial scheme with 2 additional treatments, using 3 sucrose doses (2, 4 and 8%) with 3 application times (1, 24 and 168 hours after intoxication with 10% of the commercial glyphosate dose) with an additional one in which the plants were not intoxicated and not treated with sucrose and another only with plants intoxicated by glyphosate. After 75 days performing the experiment, growth, physiological and anatomical characteristics were evaluated. The application of sucrose in the reversal of intoxication of growth variables (height, leaf area number of leaves, shoot dry weight and dry weight of the root system) was not efficient. The objective of this study was to evaluate the effect of the sucrose application on the detoxification of coffee plants in the implantation phase with glyphosate drift. For the physiological variables the application of 2% sucrose, one hour after glyphosate intoxication was the most efficient treatment. Made available in DSpace on 2020-09-04T04:39:21Z (GMT). No. of bitstreams: 1 1-2019.pdf: 265753 bytes, checksum: a03231468f8b981d21edbbdd45e8b70d (MD5) Previous issue date: 2019

The increase of atmospheric CO2 should result in higher carbon fixation by plants of the C3 photosynthetic cycle, such as coffee. However, not much is known about the relationship between atmospheric CO2 increase, higher carbon fixation through photosynthesis and the potential carbon sequestration in soil. Based on the hypothesis that there will be greater stabilization of carbon in soil due to increase of atmospheric CO2 concentration, the study was carried a field coffee grown area with FACE (Free-Air Carbon dioxide Enrichment) system. The CO2 enrichment treatment maintained the concentration of this gas 200 ?mol mol-1 above the ambient value. The stocks of carbon and nitrogen in soil and some attributes related to the humification of organic matter were evaluated 43 months after the beginning of the experiment. In addition, the decomposition of residues of coffee plants (leaves) and the emission of N2O were also evaluated. The stocks of carbon and nitrogen in soil of at 0-5 cm layer were in average 18% higher (2.6 Mg ha-1 carbon and 0.2 Mg ha-1 nitrogen) in CO2 enrichment treatment. As the decomposition of vegetal remains was not affected by atmospheric CO2 enrichment, the increase of carbon and nitrogen in soil was due to the greater contribution of vegetal material, which resulted in a less humic organic matter. In the equilibrium between carbon soil stabilization and N2O emission, the enrichment of atmospheric CO2 in the coffee crop resulted in negative feedback for global warming due to the increased sequestration potential of carbon by soil. Made available in DSpace on 2020-03-24T15:12:08Z (GMT). No. of bitstreams: 1 Ramos-NP-organic-matter-2019.pdf: 623845 bytes, checksum: 5b29cf8e45a60a7af04cbda0feb40664 (MD5) Previous issue date: 2019

Made available in DSpace on 2020-12-12T01:22:14Z (GMT). No. of bitstreams: 0 Previous issue date: 2020-04-01 Terpenoids are a diverse class of metabolites that impact plant metabolism in response to environmental cues. They are synthesized either via a predominantly cytosolic (MVA) pathway or a plastidic pathway (MEP). In Arabidopsis, several enzymes from the MVA and MEP pathways are encoded by gene families, excluding MVK and DXR, which are single-copy genes. In this study, we assess the diversity, evolution and expression of DXR and MVK genes in selected angiosperms and Coffea arabica in particular. Evolutionary analysis revealed that DXR and MVK underwent purifying selection, but the selection effect for DXR was stronger than it was for MVK. Digital gene expression (DGE) profile analysis of six species revealed that expression levels of MVK in flowers and roots were high, whereas for DXR peak values were observed in leaves. In C. arabica, both genes were highly expressed in flowers, and CaDXR was upregulated in response to methyl jasmonate. C. arabica DGE data were validated by assessing gene expression in selected organs, and by plants treated with hexanoic acid (Hx) using RT-qPCR. MVK expression was upregulated in roots treated with Hx. CaDXR was downregulated in leaves by Hx treatment in a genotype-specific manner, indicating a differential response to priming. Departamento de Biodiversidade Instituto de Biociências Universidade Estadual Paulista UNESP Laboratório de Biotecnologia Vegetal Empresa Brasileira de Pesquisa Agropecuária (Embrapa-Café) Departamento de Biodiversidade Instituto de Biociências Universidade Estadual Paulista UNESP