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Water stress in plants due to the effects of climate change resulted in reduced growth and yield of coffee in the tropics. Efficient use of water through the use of SMART irrigation systems available provides a promising solution to address such a problem. Thus, a study utilizing a combined climate- based and soil moisture SMART irrigation system has been conducted to assess its effects on the growth of Robusta coffee seedlings compared to practiced manual irrigation. The experimental design utilized a Complete Block Design (CBD) approach. Additionally, water consumption was measured to determine any significant differences. Over the course of the two-month experiment, 20 replications per treatment, it was observed that coffee seedlings subjected to the automated irrigation system (T1) exhibited significant improvements in both plant height and number of leaves, with growth rates of 72.56% and 65.29%, respectively, compared to manually irrigated plants (T0). Although the water savings achieved under the automated system were not statistically significant, there was an 18.95% reduction in water consumption. These findings highlight the potential benefits of automating irrigation systems using an IoT approach, specifically in terms of enhancing coffee seedling productivity. By utilizing real-time data from sensors, the SMART irrigation system effectively optimized water usage and resulted in improved growth and yield. This research underscores the importance of implementing such technological advancements to mitigate the adverse effects of climate change on coffee cultivation in tropical regions. [ABSTRACT FROM AUTHOR]

Animal-pollination is crucial in the reproduction of many crops grown in the tropics, including the self-incompatible Robusta coffee. Coffea canephora Pierre ex A. Froehner. is indigenous to the Congo basin where it is naturally growing in the rainforest understorey. Coffee cultivation mainly occurs in either unshaded monocultures or in agroforestry systems. Here we used pan traps to survey the Diptera (true flies) and Hymenoptera (bees) communities as the putative coffee pollinating organisms in the Yangambi region in DR Congo, and we assessed the comparative benefits of a coffee agroforestry system and coffee monoculture to the coffee pollinator community. To assess the pollinator conservation potential of the agroforestry system, we also compared its Diptera and Hymenoptera communities with natural rainforest as a benchmark. Natural rainforest harboured a higher number of individuals, as well as a higher number of species than both agroforestry and coffee monoculture systems, with no differences between the latter two land-uses. Furthermore, we observed different responses in species richness and diversity to land-use between Diptera and Hymenoptera. Our analyses further showed a high species dissimilarity between natural rainforest and the two cultivation systems, without significant differences between the latter. Specifically, the community composition of the agroforestry and coffee monoculture systems were totally different, rather than a subset of the community composition of the natural rainforest. Our study indicates that rehabilitation of agricultural land through intercropping fruit trees may not always enhance pollinator communities and that the studied agroforestry system falls short of matching the bee and fly conservation potential of natural rainforests. • Animal-pollination is vital for tropical plant and crop reproduction. • Robust pollinator communities of Coffea canephora in Congo Basin are still unknown. • Assessing agroforestry's impact on Diptera and Hymenoptera conservation. • Intercropping fruit trees may not boost pollinator diversity or services. • Tropical rainforest irreplaceable for conservation of wild bees and true flies. [ABSTRACT FROM AUTHOR]

The direct-infusion of 130 coffee samples into a Fourier-transform ion cyclotron mass spectrometer (FT-ICR-MS) provided an ultra-high resolution perspective on the molecular complexity of coffee: The exceptional resolving power and mass accuracy (± 0.2 ppm) facilitated the annotation of unambiguous molecular formulas to 11,500 mass signals. Utilizing this molecular diversity, we extracted hundreds of compound signals linked to the roasting process through guided Orthogonal Partial Least Squares (OPLS) analysis. Visualizations such as van Krevelen diagrams and Kendrick mass defect analysis provided deeper insights into the intrinsic compositional nature of these compounds and the complex chemistry underlying coffee roasting. Predictive OPLS-DA models established universal molecular profiles for rapid authentication of Coffea arabica versus Coffea canephora (Robusta) coffees. Compositional analysis revealed Robusta specific signals, indicative of tryptophan-conjugates of hydroxycinnamic acids. Complementary LC-ToF-MS2 confirmed their compound class, building blocks and structures. Their water-soluble nature allows for application across raw and roasted beans, as well as in ready-made coffee products. • Uncovering the molecular complexity of coffee brew using FT-ICR-MS; revealing over 11,500 molecular compositions. • Mapping hundreds of Maillard reaction products reveals the systematic chemical evolution from simple precursors to complex aromatic compounds during roasting. • OPLS-DA classification model distinguishes Arabica and Robusta coffee based on the comprehensive metabolite data; interpreted through molecular networks. • tryptophan conjugates of hydroxycinnamic acid derivatives characterized by LC-ToF-MS2 as water-soluble Robusta-characteristic compounds. [ABSTRACT FROM AUTHOR]

Saccharomyces cerevisiae CCMA 0159 is reported as a promising biocontrol agent against ochratoxin A (OTA)-producing fungi in coffee. Coffea arabica and Coffea canephora (var. Conilon or Robusta) are the most widely consumed coffee species around the world, cultivated in tropical and subtropical regions, each exhibiting distinct physicochemical and sensory characteristics. The objective of this study was to compare the growth and OTA production by Aspergillus carbonarius , A. ochraceus , and A. westerdijkiae in C. arabica and C. canephora , along with assessing the efficiency of S. cerevisiae CCMA 0159 in biocontrolling ochratoxigenic fungi in both coffee varieties. A. carbonarius exhibited a higher growth rate and OTA production in both coffee varieties, with C. canephora showing particular susceptibility. Conversely, A. ochraceus and A. westerdijkiae demonstrated lower growth and OTA production. S. cerevisiae was effective in biocontrolling the fungal isolates, inhibiting over 80 % of A. carbonarius growth in both coffee varieties. Among the mechanisms of action of the biological control agent, the production of volatile organic compounds stands out. The results of this study confirm the significant potential of S. cerevisiae CCMA 0159 as a biocontrol agent against Aspergillus for application in coffee-producing areas. • Aspergilus carbonarius produces more ochratoxin A in Conilon coffee. • Saccharomyces cerevisiae reduces ochratoxin A production by fungi in coffee varieties. • Change in pH and production of volatile organic compounds acted in biocontrol. [ABSTRACT FROM AUTHOR]

• SPME-GC-MS for detection of fraud in roasted and ground coffee. • Potential chemical markers of the most common adulterants in coffee fraud. • Chemometrics analysis indicate volatile compounds as possible markers for food fraud. Roasted ground coffee has been intentionally adulterated for economic revenue. This work aims to use an untargeted strategy to process SPME-GC-MS data coupled with chemometrics to identify volatile compounds (VOCs) as possible markers to discriminate Arabica coffee and its main adulterants (corn, barley, soybean, rice, coffee husks, and Robusta coffee). Principal Component Analysis (PCA) showed the difference between roasted ground coffee and adulterants, while the Hierarchical Clustering of Principal Components (HCPC) and heat map showed a trend of adulterants separation. The partial Least-Squares Discriminant Analysis (PLS-DA) approach confirmed the PCA results. Finally, 24 VOCs were putatively identified, and 11 VOCs are candidates for potential markers to detect coffee fraud, found exclusively in one type of adulterant: coffee husks, soybean, and rice. The results for possible markers may be suitable for evaluating the authenticity of ground-roasted coffee, thus acting as a coffee fraud control and prevention tool. [ABSTRACT FROM AUTHOR]

[Display omitted] • The cultivar stands out in the soluble coffee industry by yield with no lack of quality • The composition of the cultivar is affected by roasting, but not by ripeness. • Coffee reached 80 points on sensory analysis and was classified as "Fine" • 5-methylfurfural is the only compound positively correlated to all sensory attributes. • 3-CQA and 2-methoxy-4-vinylphenol were the major CGA and volatile compound founded. Coffee is one of the most consumed beverages worldwide. Espírito Santo is the largest Brazilian producer of conilon coffee, and invested in the creation of new cultivars, such as "Conquista ES8152", launched in 2019. Therefore, the present study aimed to evaluate the effects of maturation and roasting on the chemical and sensorial composition of the new conilon coffee cultivar "Conquista ES8152". The coffee was harvested containing 3 different percentages of ripe fruits: 60%, 80%, and 100%, and roasted at 3 different degrees of roasting: light, medium, and dark, to evaluate the moisture and ash content, yield of soluble extract, volatile compound profile, chlorogenic acid and caffeine content, and sensory profile. "Conquista ES8152" coffee has a moisture content between 1.38 and 2.62%; ash between 4.34 and 4.72%; and yield between 30.7 and 35.8%. Sensory scores ranged between 75 and 80 and the majority of volatile compounds belong to the pyrazine, phenol, furan, and pyrrole groups. The content of total chlorogenic acids was drastically reduced by roasting, with values between 2.40 and 9.33%, with 3-caffeoylquinic acid being the majority. Caffeine was not influenced by either maturation or roasting, with values between 2.16 and 2.41%. The volatile compounds furfural, 5-methylfurfural, and 2-ethyl-5-methylpyrazine were positively correlated with the evaluated sensory attributes and 5-methylfurfural was the only one significantly correlated with all attributes. Ethylpyrazine, furfuryl acetate, 1-furfurylpyrrole, 4-ethyl-2-methoxyphenol, and difurfuryl ether were negatively correlated. The stripping did not affect the quality and composition of this new cultivar, however, the roasting caused changes in both the chemical and sensorial profiles, appropriately indicated by the principal component analysis. [ABSTRACT FROM AUTHOR]

• Variability in floral morphology related to coffee genotypes was observed. • Coffee floral morphology changes associated with elevation. • Coffee spp. flower size was larger at low- than at high-elevation. • Flowers with five and six petals and stamens were detected in C. canephora. • Lower flower morphology variability between elevation was found in C. arabica than C. canephora. Floral traits are influenced by elevation in various species, but no information is available for the Coffea canephora and C. arabica. It was hypothesized that: 1) number of stamens and petals can vary depending on the species and genotype within the same species; 2) variations in the morphological traits occur in response to the difference in elevation, 3) greater variability in flower morphology among C. canephora genotypes is expressed at high- than at low-elevation, due to environmental pressure, and 4) the changes in floral morphology due to alterations in elevation are more pronounced in C. canephora than in C. arabica. This study aimed to investigate the G × E interaction for morphological traits of coffee flowers and, based in genetic parameters estimation, explore the potential use of these traits in breeding programs. Experiment comprised of coffee plantations under full sun of both species at two elevations. The number of petals and stamens varied between five and six in C. canephora. At two elevations, Beira Rio 8 (C. canephora) genotype stood out for presenting the highest averages for all size traits related to corolla, and stigmatic lobes. The variability in floral morphology among C. canephora genotypes was not greater at high- than at low- elevation. Overall, flower size of all studied C. canephora and C. arabica genotypes was larger at low- than at high-elevation, but the stigmatic lobes length, the ratio between stigmatic lobe length and style length, and partially the ratio between anther length and stamen length were greater at high-elevation. C. arabica flowers were smaller and mostly irresponsive to elevation, in contrast with C. canephora flowers. There was a significant genotype by environment interaction for seven out of the nine traits, with a predominance of complex-type interactions. Conducting studies on morphological traits of flowers at a greater number of environments with distinct elevations can provide better insights into the potential use of these traits in studies of adaptability and stability of Coffea spp. genotypes to different environmental conditions, contributing to genetic improvement efforts to achieve resilience of coffee cultivation in the scenarios of climate change. [Display omitted] [ABSTRACT FROM AUTHOR]

In the Central Highlands of Vietnam, coffee (Coffea canephora) and pepper (Peper nigrum) farmers have started transitioning from monoculture to mix cropping systems. To investigate this ongoing shift towards diversified systems and understand the underlying agronomic and economic drivers, a total of 234 interviews were conducted with farmers in the three provinces of Dak Lak, Dak Nong and Gia Lai in 2021. The interviews showed that farmers are increasingly incorporating coffee, pepper, and fruit trees (mostly avocado, durian, and macadamia) within their plots. This response is likely driven by market prices and government incentives. The addition of perennial crops into existing systems results in an overall increase in planting densities (+33–71% compared with monoculture systems). Despite the intensification and diversification, there is currently no noticeable competition between crops, and productivity per tree remains high in these intensive farming systems. Furthermore, diversified coffee systems exhibit higher gross margins (only considering fertilizer and pesticide costs while excluding labor costs) than monoculture coffee systems. They also demonstrate greater economic resilience to price fluctuations. Given the perennial nature of the crops, this transformation is expected to continue unfolding in the coming years, reshaping the agricultural landscape of the Central Highlands. [Display omitted] • Coffee and pepper farmers are increasingly diversifying their farming systems. • New crops are added into existing systems, increasing the overall planting densities. • Fruit trees and pepper lead to higher gross margins than coffee. • Mixed cropping systems demonstrate high economic resilience. [ABSTRACT FROM AUTHOR]

Abstract 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. Graphical abstract Unlabelled Image Highlights • Evaluation of a candidate reference material for determination of the composition of coffee blends by molecular techniques. • Detection of the main commercial coffee species in blends of roasted and ground coffee by real-time PCR. • Differentiation of Coffea arabica and C. canephora in roasted and ground coffee blends. • Adaptation of the DNA extraction protocol to determine the composition of roasted and ground coffee samples by real-time PCR. • Analysis of the authenticity of the composition of coffee blends. [ABSTRACT FROM AUTHOR]

Since the early 2000s, there has been a resurgence in shade coffee production on the island of Puerto Rico. The newly restored specialized shade canopy consists of four native tree species, three of which are nitrogen fixers, and is intended to provide 30% shade cover once the trees are matured. Though much is known about the benefits of rustic and traditional shade plantations to coffee production, there is little information available for specialized shade plantations. Here, we investigate the ways in which fruit set, seed predation, bean weight, proportion of peaberries (i.e., malformed fruits), and beverage quality differ between sun and specialized shade plantations of Coffea arabica and Coffea canephora . Additionally, to assess whether coffee plants were pollen limited, we conducted a pollen supplementation experiment in which we compared pollen deposition and berry production on hand-pollinated branches to those of naturally, open-pollinated ones. We found that there was no evidence of pollen limitation on fruit set between sun and specialized shade plantations of C. arabica or C. canephora . We found that specialized shade benefits the proportion of C. arabica fruit set, without compromising bean weight or the proportion of peaberries produced. In comparison, C. canephora showed no improvement in the proportion of fruits set with specialized shade; however, beans from open-pollinated flowers weighed more in specialized shade than sun. Beverage quality was marginally better under shade, and for hand-pollinated flowers. Our results add to the limited body of work investigating the benefits of specialized shade coffee plantations on ecosystem services. [ABSTRACT FROM AUTHOR]

Water deprivation is an important limiting factor in the productivity of crops like coffee. In addition to transcription factors (TFs) and small non-coding RNAs, transcriptional memory seems to act in gene expression modulation during plant drought response. Here, a RNA-Seq approach was used to investigate the drought responses of Coffea canephora clones 109 and 120, which are respectively sensitive and tolerant to drought. Illumina sequencing allowed us to identify differentially expressed genes (DEG) in the tolerant (826) and sensitive (135) clones and their enriched categories. Our results indicate that the sensitive clone may trigger an oxidative stress response, possibly leading to programmed cell death, when exposed to multiple drought episodes. The acclimation of tolerant plants, on the other hand, seems to involve antioxidant secondary metabolism and the ABA response. Most importantly, 49 memory genes were identified in the tolerant clone. They were mainly linked to the ABA pathway, protein folding and biotic stress. Small RNA profiling also identified regulatory microRNAs in coffee leaves, including hundreds of putative novel ones. Our findings strongly suggest that transcriptional memory modulates the expression of drought-responsive genes and contributes to drought tolerance in C. canephora. [ABSTRACT FROM AUTHOR]

This work was performed to evaluate the possible application of PTR-ToF-MS technique in distinguishing between Coffea arabica (Arabica) and Coffea canephora var. robusta (Robusta) commercial stocks in each step of the processing chain (green beans, roasted beans, ground coffee, brews). volatile organic compounds (VOC) spectra from coffee samples of 7 Arabica and 6 Robusta commercial stocks were recorded and submitted to multivariate statistical analysis. Results clearly showed that, in each stage of the coffee processing, the volatile composition of coffee is highly influenced by the species. Actually, with the exception of green beans, PTR-ToF-MS technique was able to correctly recognize Arabica and Robusta samples. Particularly, among 134 tentatively identified VOCs, some masses (16 for roasted coffee, 12 for ground coffee and 12 for brewed coffee) were found to significantly discriminate the two species. Therefore, headspace VOC analyses was showed to represent a valuable tool to distinguish between Arabica and Robusta. [ABSTRACT FROM AUTHOR]

16- O -Methylcafestol (16-OMC), the characteristic diterpene exclusively present in Coffea canephora , is an excellent marker for Coffea canephora admixtures to Coffea arabica . Here we show a straightforward, selective and sensitive screening method for the determination of 16-OMC in roasted coffee by high-performance thin-layer chromatography with fluorescence detection (HPTLC–FLD). As internal standard, Sudan IV was used, and a direct saponification with 10% ethanolic potassium hydroxide solution was followed by solid supported liquid extraction with petroleum ether. 16-OMC was selectively derivatized with 2-naphthoyl chloride and analyzed by HPTLC–FLD on silica gel plates with cyclohexane/ tert -butyl methyl ether/formic acid (86:14:2, v/v/v ) as the mobile phase. The enhanced fluorescence was scanned at UV 244/ > 320 nm. Limits of detection and quantitation of 5 and 14 mg 16-OMC/kg coffee allowed the determination of Coffea canephora admixtures to Coffea arabica below 1%. Recoveries for blends of Coffea arabica with Coffea canephora were close to 100%. [ABSTRACT FROM AUTHOR]

The chemical investigation of the methanolic leaf and root extract of Coffea canephora Pierre ex A. Froehner (Rubiaceae) led to the isolation and structure elucidation of seventeen known compounds including three alkaloids: caffeine (1), theobromine (2) and paraxanthine (3); two diterpenes: tricalysiolide B (4) and 16,17-dihydroxykauran-18-oic acid (5); six triterpenoids: lupeol (6), 3 β -acetylated oleanolic acid (7), ursolic acid (8), friedelin (9), polycarpol (10) and squalene (17); two phytosterols: stigmasterol (11) and stigmasterol-3- O - β -D-glucopyranoside (12); two phenolic compounds: 3,5-dihydroxy-7,8,2ʹ,3ʹ,4ʹ-pentamethoxyflavonol (13), 2,3,5-trimethoxyphenol (14) and two miscellaneous compounds: asperphenamate (15) and chlorophyll A (16). The structures of the isolates were established by extensive spectroscopic and spectrometric analyses (1D and 2D NMR, ESI-MS) and by comparison with previously reported data. Compounds 10 and 14 were reported for the first time from Rubiaceae family, whilst compounds 13 and 15 were reported for the first time from Coffea genus. In addition, some isolates were tested for their antibacterial and antifungal effects against various strains. Compounds 5 and 8 displayed moderate antibacterial activities against Shigella dysenteria with MIC value of 125 μg/mL, whilst compound 8 showed moderate antifungal activity against Candida krusei with MIC value of 125 μg/mL. Furthermore, the chemophenetic significance of the isolates is discussed in details. [Display omitted] • Seventeen isolates from the leaf and root extracts of Coffea canephora Pierre ex A. Froehner. • Caffeine, a chemophenetic marker of Coffea genus was isolated. • Two compounds were reported for the first time from Rubiaceae family. • Chemophenetic significance of the isolated was discussed. [ABSTRACT FROM AUTHOR]

Two main types of processing are applied to coffee: the dry and wet processes. The aim of this study was to measure the impact of post-harvest processing on coffee microbial ecology and search for microbial markers of process discrimination. Coffee samples were collected in three farms in two locations of West Cameroon (Bafoussam and Dschang). Samples of Coffea arabica were collected along wet and dry methods and Coffea canephora samples were collected only during treatment using the dry method. Bacterial and fungal communities present on coffee beans were determined by using a molecular method PCR-DGGE (Denaturing Gradient Gel Electrophoresis) generating 16S rDNA and 26S rDNA profiles for bacteria and fungi. Results showed that microbial ecology structures were different depending on three main parameters: i) the method applied, ii) the coffee species and iii) their geographical origin. Statistical analysis applied allowed to measure the impact of all parameters and showed that the method was the major parameter influencing microbial communities' structure. Microbial DNA markers that appear specific of coffee origin, species or treatment were identified, such as lactic acid bacteria (LAB) which were detected only during wet process. They are specific of the fermentation step. DNA from Wallemia sp. was only detected in Robusta coffee beans ( Coffea canephora ). The study of microbial communities at the molecular level appears as a promising approach to discriminate between coffee processing types. [ABSTRACT FROM AUTHOR]

Green coffee beans of Coffea arabica and Coffea canephora accessions from different geographical origin (Brazil, Colombia, Ethiopia, Honduras, Kenya, Mexico, Peru, Uganda and Vietnam) were extracted and the extracts analyzed by HPLC–ESI-MS/MS for the identification and quantification of chlorogenic acids and caffeine content. Principal component and cluster analyses were used to identify chemical patterns separating the different species and accessions based on their geographical origin. C. canephora showed always a higher caffeine content with respect to C. arabica , whereas the C. arabica accessions from Kenya showed a higher chlorogenic acids and a lower caffeine content. The antioxidant capacity of green coffee extracts was assayed by the reducing power and DPPH assays. The antioxidant capacity correlated with the chlorogenic acids content. The results show that the C. arabica from Kenya possesses the highest chlorogenic acids/caffeine ratio and, among the C. arabica accessions, the highest antioxidant capacity. Therefore, the C. arabica from Kenya is the most suitable green coffee source for nutraceutical applications because of its high antioxidant capacity and low caffeine content. [ABSTRACT FROM AUTHOR]

[Display omitted] • 1H NMR and advanced data analysis methods for evaluating fermented coffees. • Starter fermentation with Saccharomyces cerevisiae provided better sensory quality. • The chemical and sensory profiles of fermented coffees are correlated. • Lipids are important markers for the quality of fermented conilon coffee. The potential impact of fermentation on coffee quality has been the target of several scientific studies. In this perspective, we present a design of different fermentation processes applied to coffees of the Coffea canephora var. conilon. Thus, coffee samples were submitted to six fermentation methods, at five different times (24, 48, 72, 96, and 120 h). Sensory analysis and hydrogen nuclear magnetic resonance (1H NMR) were used in roasted coffees, to understand aspects of quality and chemical profile, respectively. Variable selection by Fisher discriminant (FD), and multivariate data analysis, including principal component analysis (PCA), partial least squares-discriminant analysis (PLS-DA), and support vector machine (SVM) were used to extract the main chemical information and establish direct relationships with coffee sensory quality. The results indicated chlorogenic acids, caffeine, γ-butyrolactone, lipids, sugars, and acetic acid as responsible for the discrimination of the different fermentation processes. In addition, lipids were characteristic in coffees with higher sensory scores, indicating they are an important marker for the quality of the beverage. [ABSTRACT FROM AUTHOR]

The maintenance of rejuvenated, productive plant tissue through regular and frequent pruning is essential to sustain high and stable coffee yields. Different coffee pruning systems have been described by means of well-written descriptions, and ingenious drawings and graphs. The mathematical representation of coffee pruning systems has never been attempted. Until now. To develop a mathematical modeling approach capable of describing plant tissue age and coffee bean yield dynamics for any coffee pruning system. In this paper, we develop mathematical models for simple (Nicaragua) and complex (El Salvador) coffee pruning system by using a special type of additive age-projection matrix, clock arithmetic, step functions, and coffee yield-age functions developed using expert knowledge. Simulations were run to answer three fundamental crop management questions: 1) how many years is the best pruning cycle, 2) when (at what age?) to start pruning, and 3) how different yield-age functions influence decisions on the best pruning cycle and age at first stumping?. Coffee pruning models can help coffee agronomists to design and test innovative pruning practices quickly, efficiently, and cheaply. Pruning models can be coupled with financial data to improve decision making in crop management. The mathematical approach used for Arabica coffee pruning systems is equally applicable to Robusta coffee. [Display omitted] • Coffee pruning systems are modeled using age projection matrices, clock arithmetic, step functions and yield-age functions. • Models were developed for simple and complex pruning systems. • Pruning models are useful to assess the effects of pruning cycles, age at first pruning, and yield-age functions. [ABSTRACT FROM AUTHOR]

Coffee is recognized by its bioactive potential, mainly antioxidant and antimicrobial activity. The aim of this study was to evaluate the antimicrobioal potential of aqueous extracts of Coffea arabica (AR) (roasted) and Coffea canephora [roasted (CR) and green (CG)] against patogens Salmonella Typhimurium and Escherichia coli, and probiotics Lactobacillus plantarum and Lactobacillus rhamnosus. Firstly, the strain's sensitivity were tested by disk diffusion method, followed by the evaluation of growth kinetics (lag phase duration, maximum specific growth rate and logarithmic increase in the population) in culture media and in a food matrix (milk) by the adjustment of Gompertz predictive model. In the step of strain sensivity tests, S. Typhimurium and E. coli were sensitive against all coffee extracts from 0.5% to 5.0%, while the Lactobacilli growth were not affected. In the growth kinetic tests in culture media, roasted coffees extracts reduced logarithmic increase in the population and maximum specific growth rate and improved lag phase for S. Typhimurium; for E. coli the growth was completely inhibited with 2.5% CR and 5.0% AR. The correlations between growth parameters with coffee bioactive contents suggested that melanoidins had the main antimicrobial effect. In the step of food matrix application (growth kinetics in milk), the addition of 5.0% CR reduced S. Typhimurium and E. coli multiplication, while the probiotics L. plantarum and L. rhamnosus where not inhibetd, suggesting a selective effect of coffee extracts as an antimicrobial agent, which may be of great interest for the food industry, especially for probiotic foods application. [Display omitted] [ABSTRACT FROM AUTHOR]

Root-knot nematodes (Meloidogyne spp.) are non-quarantine pests that are subject to regulations in Brazil because they are limiting to coffee production and easily spread by planting infected seedlings. Containing their dissemination requires knowledge of their distribution in coffee-producing areas in order to establish phyto-sanitary measures. The object of this work is to evaluate the distribution of Meloidogyne spp. in Coffea spp. in Espírito Santo state, where coffee growing is expanding. Soil and root samples were collected in Coffea arabica and Coffea canephora Conilon. Identification of Meloidogyne spp. was carried out by esterase isoenzyme phenotype and by the host range. In Espírito Santo, Meloidogyneincognita, Meloidogyne exigua, and Meloidogyne paranaensis were identified. Phenotypes I1 and I2 of M. incognita were present in 21% of all the sampled properties. This species was found mainly in the Serrana region and north of the state, and principally in plantations of C. canephora. Only phenotype E1 of M. exigua was detected, distributed in 23.8% of the properties and only in plantations of C. arabica. M. exigua was found in all the municipalities sampled in the southern region of the state and in 66.6% of the municipalities of the Serrana region. M. paranaensis, phenotype P1, was detected only in the northern region, and in 100% of the properties sampled in Baixo Guandu municipality. The study was complemented by sampling in the Zona da Mata region of Minas Gerais state, where only M. exigua, phenotype E1, was found in C. arabica plantations. M. exigua was detected in all the sampled municipalities except Paula Cândido. The populations were subjected to differential host plant tests to determine the physiological races. Races 1 and 2 of M. incognita and M. exigua were found in Espírito Santo state, and race 2 of M. exigua in Zona da Mata in Minas Gerais state. The presence of the three most important root-knot nematodes in coffee plants in Espírito Santo state indicates the need to establish measures that will contain their dissemination. [ABSTRACT FROM AUTHOR]

Interspecific C×R hybrid (Coffea congensis × Coffea canephora) in India is cultivated as mixed population with male parent C. canephora as this species is an efficient pollen donor for enhanced yield. But distinction of C×R hybrid from C. canephora in old plantation is difficult due to varying plant sizes of C×R hybrid and often resembles with C. canephora. C×R hybrid cultivated under different agroclimatic conditions show distinct vegetative growth pattern with varying yields. Thus development of DNA marker for identification of C×R hybrid is important for clonal propagation and seed preparation from selective individuals. In this study, two DNA bar coding loci of chloroplast genome (rbcL and matK) of parents, F1 hybrid and its back cross progeny were partially sequenced to identify SNPs as DNA marker for distinction of C×R hybrid from C. canephora. Seven SNPs in the matK gene sequence and three nucleotides in the rbcL gene sequence were identified as DNA markers for the genetic identity of C. congensis. These SNPs were found in F1 and advanced progenies of C×R hybrid due to maternal inheritance. Large number of samples of C×R hybrids with varying morphological features revealed no polymorphism among C×R hybrid and C. congensis. Thus, the SNPs in C. congensis can be used as DNA markers for precise identification of C×R hybrid for production of clones besides tagging the chloroplast inheritance in advanced progenies. [ABSTRACT FROM AUTHOR]

Abstract: Forest fragments in agricultural landscapes are recognised to provide a variety of ecosystem services, several of which benefit neighbouring agricultural land uses. Pollination of crops is one such service that has attracted much research and public attention, yet the dependency of crops on pollinators, and the role of forest fragments in providing this service, remains contentious. Indeed, the trend towards increasing crop production through intensification is at odds with the expected concurrent decline in pollination. We investigated the combined effect of distance from forest and forest size on pollinator abundance at coffee agro-forests in Kodagu District, India, under two contrasting flowering scenarios: irrigation triggered flowering in a single agro-forest, and rain triggered flowering at all the remaining agro-forests that received rain but were not previously irrigated. Three social bee species, Apis dorsata, Apis cerana and Tetragonula iridipennis were the main flower visitors. In rain-fed agro-forests, the total visitor abundance at coffee flowers decreased with increasing distance to the nearest forest. When the three main pollinators were analysed separately, the abundances of A. dorsata and T. iridipennis decreased with increasing distance from a neighbouring forest patch but this distance effect was reduced with an increase in size of the nearby forest. An increase in pollinator abundance at coffee flowers increased coffee fruit set in rain-fed agro-forests. Irrigated agro-forests had far higher pollinator abundance and fruit set than rain-fed agro-forests. We attribute this to the small-scale staggered flowering of irrigated agro-forests resulting in the concentration of pollinators at these sites regardless of its proximity to forests or the size of nearby forest. Agro-forest shade tree species richness also negatively affected pollinator abundance in rain-fed agro-forests. Although our results show that distance to forest and size of neighbouring forest fragments do affect the abundance of pollinators at coffee, at least in rain-fed agro-forests, justifying the conservation of large forest remnants is problematic on this account as there was no direct effect of forest on coffee fruit set. This is likely to be because there remains a high density of forest remnants within Kodagu, and a threshold of forest cover at which crop fruit set begins to be affected by pollinator scarcity has yet to be reached. By controlling the timing of flowering through irrigation or managing domesticated bee hives, farmers effectively reduce the dependency on nearby forest cover for pollinator services irrespective of the distance between forests and agro-forests, but these management practices incur costs that not every farmer can cover. [Copyright &y& Elsevier]

Abstract: The association of hevea with other tree crops was investigated with the aim of providing guidelines for farmers who wish to diversify their sources of income and maximize their land use. We compared standard hevea monocrop with hevea intercropped with coffee, cacao, lemon or cola in a field trial in south-western Côte d’Ivoire. In crop associations, hevea trees were planted in a double hedgerow with wide inter-rows (16m) to favour the growth and yields of lower-stratum tree crops. Yields and the different inputs for each crop in each treatment were recorded for 17 years. The results showed that the yield of individual hevea trees was not affected by the intercropped trees. Thanks to the 16-m inter-rows, the productivity of the intercropped trees improved and the competitive effect of shading by hevea was delayed three years. In the conditions of the trial, the hevea-coffee and hevea-cacao associations were significantly more profitable than other associations until the 12th year. The additional gross margins were positive from the third year on for the hevea-coffee association and from the fourth year on for hevea-cocoa association. Grown as a monocrop, hevea only reached the breakeven point in the eighth year. During the 17-year observation period, both the hevea-coffee and hevea-cacao association were more profitable than the standard hevea monocrop; but after the 13th year, the difference was no longer significant. By contrast, the hevea-lemon association was not profitable due to the low price of lemon fruits, and the hevea-cola association was not profitable because the cola-trees only started yielding from the seventh year. Taken together, in the associations, hevea revenues accounted for 88% of the total revenues and intercrops for 4% (cola) to 25% (coffee). [Copyright &y& Elsevier]

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Abstract: The bioactive composition of coffee, as one of the most popular beverages in the world, has attracted interest as a potential source of beneficial bioactive compounds, especially polyphenols and caffeine. Since the content of these compounds is affected by the processing conditions, the objective of this study was to determine the content of polyphenolic compounds and caffeine in four different coffee varieties: Minas and Cioccolatato (Coffea arabica), and Cherry and Vietnam (Coffea canephora syn. Coffea robusta), roasted by three varying degrees (light, medium and dark). The content of the polyphenolic compounds and the antioxidant capacity of coffees were determined using UV/Vis spectrophotometric methods, while the content of chlorogenic acid derivatives was determined using HPLC analysis. The caffeine content was determined by means of two spectrophotometric methods, as well as HPLC analysis. Additionally, raw caffeine was also obtained by an isolation procedure with chloroform. Cherry coffee, a variety of C. canephora exhibited the highest overall content of total phenols (42.37mg GAE/g), followed by Minas coffee, while Cioccolatato contained the lowest TPC (33.12mg GAE/g). Cherry coffee also exhibited the highest content of individual classes of polyphenols (flavan-3-ols, procyanidins and tannins), while the highest content of chlorogenic acid (CQA) derivatives was determined in Minas and Cioccolatato coffees (C. arabica). The highest content of total and individual polyphenolic compounds was determined in coffees roasted in both light and medium roasting conditions, which was also observed for the content of CQA derivatives and antioxidant capacity of roasted coffees. The highest caffeine content in the coffee samples was determined by employing the HPLC analysis (0.06–2.55%). Light roasted Cherry coffee contained the highest overall content of caffeine among all coffees, which exhibited a decrease with intensified roasting. [Copyright &y& Elsevier]

Abstract: Plant genome size has been measured by flow cytometry using propidium iodide as a dye for nuclear DNA staining. However, some authors have reported the occurrence of genome size estimation errors, especially in plants rich in secondary metabolites, such as the coffee tree. In this context, we tested an alternative cytometric protocol using the SYBR Green I as a fluorochrome for stoichiometrically staining nuclear double-stranded DNA in Coffea canephora (2x) and Coffea arabica (4x). The results showed that the respective mean genome size measured from nuclei stained with SYBR Green I and propidium iodide was statistically identical. However, the G 0/G 1 peaks of nuclei stained with SYBR Green I exhibited lower coefficient variations (1.57–2.85%) compared to those stained with propidium iodide (2.75–4.80%). Coefficient variation statistical data suggest that SYBR Green I is adequate for stoichiometric nuclei staining using this methodology. Our results provide evidence that SYBR Green I can be used in flow cytometry measurements of plants, with the advantages of minimizing errors in nuclear DNA content quantification, staining relatively quicker, with high affinity, and being less mutagenic than propidium iodide. [Copyright &y& Elsevier]

Abstract: The production of soluble coffee starts with the selection of beans and is followed by roasting, grinding, extraction and drying. Lyophilised soluble coffees extracted by various methods from light, medium and dark-roasted arabica and robusta beans were evaluated for antioxidant activity (AA) using ABTS, Folin, DPPH and FRAP techniques. Caffeine, chlorogenic acid (5-CQA) and melanoidin content was also quantified. The data were analysed by principal component analysis. The AA values derived from the various methods used were correlated. Roasting resulted in the degradation of 5-CQA and formation of melanoidins, while AA was largely unaffected by roasting. The extraction of soluble coffee more prominently affected the AA of light-roasted coffee, mainly because it favoured the extraction of 5-CQA. The larger caffeine content in robusta coffee resulted in greater AA. All of soluble coffee products studied possessed antioxidant potential, which was conferred by their concentrations of phenolic compounds, caffeine and melanoidins. [Copyright &y& Elsevier]

Abstract: In this work, the pyrolysis of different Cuban biomass such as: sugar cane bagasse, coffee, residue of tobacco and sawdust of pine has been studied. The pyrolysis was carried out at different temperatures in a small furnace placed at the injection port of a gas chromatograph coupled to a Fourier transform infrared spectrometer (Py-GC/FTIR). Thermogravimetric analysis (TGA) was also carried out using a thermobalance. For tobacco residue, pyrolysis yield of charcoal and liquid products decreases with pyrolysis temperature (300–600 °C). When the pyrolysis is carried out at 300 °C charcoal yield is similar for tobacco residue, sawdust of pine and husk of coffee (≈40%) while for husk of coffee and sugar cane bagasse the charcoal yield is lower but the yield of the liquid product is higher. [ABSTRACT FROM AUTHOR]

Abstract: Roasted coffee contains a complex array of volatile organic compounds (VOCs) which make an important contribution to the characteristic flavour and aroma of the final beverage. It is thought that a few of the potent coffee aroma components, such as “β-damascenone”, could be derived from carotenoid precursors. In order to further investigate the potential link between carotenoids and coffee aroma profiles, we have measured the carotenoid content in developing coffee grain. The data obtained confirms the presence of lutein in the grain, and additionally shows that the immature coffee grain also contains significant amounts of β-carotene, α-carotene, violaxanthin, and neoxanthin. Complimentary quantitative gene expression analysis revealed that all the carotenoid biosynthetic genes examined are expressed in the grain, and that the transcript levels are gene and stage dependent. Furthermore, consistent with the reduction of the carotenoid levels at the last stage of grain development (mature-red), most of the transcript levels were also found to be lower at the final developmental stage. Quantitative expression analysis of the carotenoid genes was also carried out for the developing pericarp tissue of the coffee cherries. Again, all the genes examined were expressed, and in most cases, the highest transcript levels were detected around the large green–yellow stages, a period when carotenoid synthesis is probably greatest. [Copyright &y& Elsevier]

[Display omitted] • Cold brew characteristics depended more on coffee species than on brewing conditions. • All beverages presented a dominance of coffee flavor and bitter taste. • All beverages were equally preferred. • Sour taste and coffee flavor were more dominant in Arabica cold brews. • Bitter taste and astringent sensation were more dominant in Robusta cold brews. The study aimed to assess the dominant sensory attributes and preference for cold brews prepared with different coffee species under different brewing conditions. Four beverages were brewed using Arabica and Robusta coffees with either a coarser coffee grind and extraction at 5 °C or a finer grind and extraction at 15 °C. Coffee flavor and bitter taste were dominant sensory attributes of all beverages, regardless of material and preparation. While there were no differences in preference, the composition and dominant sensory attributes differed among the cold brews. The use of different coffee species had a greater impact on the composition and the perception of the attributes of the cold brews than brewing conditions. Sourness and coffee flavor were more dominant in Arabica cold brews, which had higher trigonelline content and acidity, but bitter taste dominance was further reported. Meanwhile, bitterness and astringent sensation were more dominant in Robusta cold brews, with higher caffeine and total chlorogenic acid content; however, a high coffee flavor dominance was also observed. [ABSTRACT FROM AUTHOR]

Abstract: Low-grade coffee beans (triage) are widely known to adversely affect the beverage quality. These represent about 15–20% of coffee production on weight basis and attempts are being explored for their utilization. These beans were evaluated for the physico-chemical characteristics and subjected to soxhlet extraction using the solvents (viz., hexane, chloroform, acetone and methanol successively). The extracts were evaluated for antioxidant potential through in vitro models such as radical scavenging activity (α,α-diphenyl-β-picrylhydrazyl radical), antioxidant activity (β-carotene-linoleate model system), reducing power (iron reducing activity) and antioxidant capacity (phosphomolybdenum complex). Highest yield of extract (12%) was obtained with methanol followed by hexane (8%) and chloroform (1.5%). Lowest was obtained with acetone (<1%). Also, it was observed that methanol extract was found to exhibit maximum radical scavenging activity (92.5%) followed by extracts obtained with acetone (81%) and chloroform (25%) at 100ppm concentration. Further, the methanol extract showed antioxidant activity (58%) at 100ppm concentration, while the other extracts viz., acetone, chloroform and hexane exhibited 44%, 28%, and 14%, respectively, at the same concentration. The antioxidant capacity of the methanol extract and propyl gallate showed 1367±54.17 and 5098±34.08μmol/g (as equivalents to ascorbic acid). Reducing power of the extract and standard compounds is in the following order ascorbic acid>chlorogenic acid>BHA>methanol extract. The methanol extract was found to contain total phenolics (21.90±0.50%), chlorogenic acid (34.16±0.27%) and caffeine (8.25±0.36%). The high antioxidant potential of the methanol extract of low-grade coffee beans is due to the presence of phenolic compounds including chlorogenic acids, which make them more suitable as a source of natural antioxidant and their utility can be explored in food industry. [Copyright &y& Elsevier]

Abstract: In anti-sense and RNA interference transgenic plants of Coffea canephora in which the expression of CaMXMT1 was suppressed, caffeine biosynthesis from [8-14C]adenine was investigated, together with the overall metabolism of [8-14C]adenine. Compared with wild type control plants, total purine alkaloid biosynthesis from adenine and conversion of theobromine to caffeine were both reduced in the transgenic plants. As found previously, [8-14C]adenine was metabolised to salvage products (nucleotides and RNA), to degradation products (ureides and CO2) and to purine alkaloids (theobromine and caffeine). In the transgenic plants, metabolism of [8-14C]adenine shifted from purine alkaloid synthesis to purine catabolism or salvage for nucleotides. HPLC analysis revealed a significantly reduced caffeine content in the transgenic plants. A small quantity (less than 20nmolg−1 fresh weight) of xanthosine had accumulated in at least one of the transgenic plants. [Copyright &y& Elsevier]

Abstract: α-d-Galactosidase (α-Gal; EC 3.2.1.22) is one of three principal enzymes involved in the modification or degradation of plant cell wall galactomannans. In the present paper it is shown that α-galactosidase activities in field-grown coffee beans are variable amongst cultivars of the two species investigated (Coffea arabica and C. canephora var. Robusta). Higher activities were found in Arabica cultivars. Using beans from greenhouse-cultivated C. arabica as a model, we showed that α-Gal activity was undetectable in the bean perispem tissue, but increased gradually during the endosperm development, to reach a peak at approximately 30 weeks after flowering (WAF) which coincided with the hardening of the endosperm. α-Gal-specific transcripts detected at 22 and 27 WAF accompanied the peak of α-Gal activity, but were reduced to be undetectable in mature beans at 30 WAF, while α-Gal activity still persisted. Two isoforms were distinguished in 2-DE profiles of crude protein extracts by N-terminal sequencing analysis. Analysis of two-dimensional gel electrophoresis profiles demonstrated that both isoforms accumulated in a linear fashion throughout grain maturation. α-Gal activity was also observed to increase to high levels during in vitro germination of coffee beans suggesting an important function of this enzyme in this process. α-Gal cDNA sequences from Arabica and Robusta were sequenced and their deduced proteins appeared to be very similar, differing by only eight amino acids. Southern-blot analysis suggests that the enzyme was encoded by at least two genes in C. arabica that could explain the existence of the two isoforms identified in 2-DE profiles. [Copyright &y& Elsevier]

Abstract: After the reunion of North and South Vietnam in 1975, the area under small-holder, irrigated cultivation of Coffea canephora increased by a factor of 10 in the Central Highlands. The actual acreage under coffee in Dak Lak province is estimated to be over 260,000ha, representing 60% of the national production, with 405,000t per year for the world market. Vietnam is presently the second largest exporter worldwide and expansion is still going on. In response to farmers’ alarming reports of apparent water scarcity in the dry season, this paper assesses the groundwater recharge in the Ea Tul watershed, a representative area in the Central Highlands region. The groundwater recharge is estimated by means of a steady-state, water balance model and validated by means of historical data, stream gauge records at the basin''s outlet and groundwater level fluctuations in wells nearby the study area. To account for the variability from one year to another, the input of the water balance equation was subjected to a frequency analysis. The estimates indicate that the expected annual groundwater recharge is 743mm in a wet year, 517mm in an average and 361mm in a dry year. Validation and literature reviews confirm these figures. Subsequently the model is used to evaluate the issue of aquifer depletion and to verify whether a combination of optimal irrigation management and optimal land allocation for Robusta coffee could solve the apparent water shortages in the coffee sector. Allowing for a minimum river discharge under very dry circumstances (i.e. the Q90 of river base flow), the sustainable yield from the aquifer for variable climatic conditions is calculated. The results confirm that with the present irrigation application depths, the groundwater is likely to be depleted in dry years, but not in wet and average years. Reducing the irrigation application depths could keep the groundwater balance positive in all years. Optimization of land allocation for C. canephora may offer an alternative way out. A reduction by 35% of the present coffee area in Ea Tul along with irrigation efficiency improvement could keep the groundwater resources in balance and guarantees a minimum river discharge, even during severe dry seasons. [Copyright &y& Elsevier]

An irrigation study was carried out to evaluate farmers’ irrigation practices on Rhodic Ferralsols which dominate the Dak Lak basalt plateau of Central Vietnam, where Robusta coffee has dramatically expanded over the last years. The experiment aimed at testing crop response on three irrigation application depths; 100 mm (advised dose), 80 and 60 mm. Initially the one-dimensional WAVE 2.1 model was evaluated for its prediction capabilities of soil water dynamics under tropical conditions. The model was calibrated with an experimental dataset of 2001, validated with an independent dataset of 2002, and verified with statistical indicators such as average error, root mean square error, model efficiency and coefficient of residual mass. The results validated the simulation with an overall model efficiency that increased towards the deeper soil layers. Subsequently the model was used to evaluate the issue of over-irrigation and to verify the water requirement for Coffea canephora. Therefore soil water stress was related to the physiology of coffee blossoming. Seven to eight days of optimal root water extraction after an irrigation event is an absolute minimum for optimal flower set. The lowest simulated irrigation depth of 60 mm indicated no water stress for 13 days after irrigation. Data collected in situ confirmed this. No significant differences in blossom set, yield and harvest quality were observed between the three treatments. A reduction of the actually advised application depth to 60 mm whenever soil water content drops below 30 vol.% (on average every 20–25 days) can hence be advised. This goes hand in hand with a reduction in deep percolation losses of 40%. [Copyright &y& Elsevier]

The coffee disease complex known as corky-root, composed of the root-knot nematode Meloidogyne arabicida and Fusarium oxysporum, causes serious damage to Coffea arabica in Costa Rica. Resistance to Meloidogyne arabicida alone and to the field population (M. arabicida, M. exigua, F. oxysporum) was evaluated under controlled and field conditions. The studied material consisted of subspontaneous-derived C. arabica accessions, C. canephora accessions, introgression lines derived from the interspecific Timor Hybrid (C. arabica×C. canephora) and F1 hybrids from crosses between subspontaneous-derived accessions and cultivars. Accessions resistant to M. arabicida and to the field population were identified at varying frequencies in the different groups of study materials. The results showed that resistance to corky-root is heritable and that genetic resistance to M. arabicida is an effective strategy against corky-root disease. By using C. canephora rootstocks, it was possible to substantially reduce mortality in the field and reduce by half the number of plants with corky-root symptoms. The results were used to define appropriate strategies for the sustainable management of coffee corky-root disease resistance. [Copyright &y& Elsevier]

The effects of water deficit on photochemical parameters and activities of superoxide dismutase (SOD), catalase (CAT) and ascorbate peroxidase (APX), as well as, cellular damages were investigated in two clones of Coffea canephora differing in drought tolerance. After 6 days without irrigation, predawn leaf water potential fell to −3.0 MPa that was accompanied by the suppression of net photosynthesis in both clones. The variable to maximum chlorophyll fluorescence ratio remained unchanged regardless of the imposed treatments. Both clones showed a similar decline (about 25%) in the photochemical quenching coefficient, but only the drought-sensitive clone exhibited an enhancement (31%) of thermal deactivation under water deficit conditions. The quantum yield of electron transport decreased similarly in both genotypes. Under drought conditions, activities of SOD, CAT and APX increased to a greater extent in the drought-tolerant clone than in the drought-sensitive one. This seemed to be matched with higher protection against oxidative stress, as judged from the lower levels of lipid peroxidation and electrolyte leakage in the drought-tolerant clone. Thus, the ability to increase the antioxidant system activity in order to limit cellular damages might be an important attribute linked to the drought tolerance in C. canephora. [Copyright &y& Elsevier]

• Forecasting capability of coffee yield models at the farm scale was assessed. • The modelling approach involved Bayesian and machine learning methods. • Potential predictors included farm data, agroclimatic and remotely sensed indices. • Coffee yields were predicted with reasonable accuracies. • In-season models' forecast skills depend on data availability and selected predictors. Timely and reliable coffee yield forecasts using agroclimatic information are pivotal to the success of agricultural climate risk management throughout the coffee value chain. The capability of statistical models to forecast coffee yields at different lead times during the growing season at the farm scale was assessed. Using data collected during a 10-year period (2008-2017) from 558 farmers across the four major coffee-producing provinces in Vietnam (Dak Lak, Dak Nong, Gia Lai, and Lam Dong), the models were built through a robust statistical modelling approach involving Bayesian and machine learning methods. Overall, coffee yields were estimated with reasonable accuracies across the four study provinces based on agroclimate variables, satellite-derived actual evapotranspiration, and crop and farm management information. Median values of prediction mean absolute percentage error (MAPE) ranged generally from 8% to 13%, and median root mean square errors (RMSE) between 295 kg ha−1 and 429 kg ha−1. For forecasts at four to one month before harvest, errors did not vary markedly when comparing the median MAPE and RMSE values. For farms in Dak Lak, Dak Nong, and Lam Dong, the median forecasting MAPE and RMSE varied between 13% and 16% and between 420 kg ha−1 and 456 kg ha−1, respectively. Using readily and freely available data, the modelling approach explored in this study appears flexible for an application to a larger number of coffee farms across the Vietnamese coffee-producing regions. Moreover, the study can serve as basis for developing a coffee yield predicting forecasting system that will offer substantial benefits to the entire coffee industry through better supply chain management in coffee-producing countries worldwide. [ABSTRACT FROM AUTHOR]

• Superheated steam (SHS) was compared with hot air for roasting Robusta coffee beans. • Acrolein, acrylamide and PAHs in coffee beans were monitored. • Acrolein was not detected in any roasted bean samples. • Medium and dark roasting by SHS at 250 °C led to beans with lower acrylamide levels. • Major PAHs in dark-roasted beans were lower when roasted at 250 °C in SHS. Although hot air (HA) is a conventional roasting medium for coffee beans, HA roasting is known to result in possible formation of toxic compounds, including acrolein, acrylamide and polycyclic aromatic hydrocarbons (PAHs). Superheated steam (SHS) roasting is therefore proposed as an alternative means to alleviate the formation of these toxic compounds in roasted coffee beans. Robusta coffee beans were roasted either with HA or SHS in a fluidized bed roaster at 210–250 °C until the bean color reached the targeted roast levels. The contents of acrolein, acrylamide and 16 PAHs in the roasted beans were determined; only acrylamide and 5 PAHs were nevertheless found. SHS roasting interestingly resulted in lower acrylamide contents in dark-roasted beans; similar trend was noted in the beans medium-roasted at 250 °C. The contents of three-ring PAHs, namely fluorene, phenanthrene and anthracene, in dark-roasted beans were significantly lower upon SHS roasting at 250 °C. [ABSTRACT FROM AUTHOR]

• A dynamic, process-based model is proposed for simulating robusta coffee growth. • The model quantifies interactions between solar radiation, temperature and water at a daily time step. • Independent climate and historical yields datasets are used for model evaluation. • Good agreements between predicted and reported yields at the provincial scale were found. • The model can be used readily within an integrated climate-robusta production forecasting system. Reliable and timely prediction of robusta coffee (Coffea canephora Pierre ex A. Froehner) yield is pivotal to the profitability of the coffee industry worldwide. In this study we assess the performance of a simple process-based model for simulating and predicting robusta coffee yield at the regional scale in Vietnam. The model includes the key processes of coffee growth and development and simulates its response to variation in climate and potential water requirements throughout the growing season. The model was built and evaluated for the major Vietnamese robusta coffee-producing provinces Dak Lak, Dak Nong, Gia Lai, Kon Tum, and Lam Dong, using official provincial coffee yield data and climate station data for the 2001–2014 period, and field data collected during a 10-year (2008–2017) survey. Overall, good agreements were found between the observed and predicted coffee yields. Root mean square error (RMSE) and mean absolute percentage error (MAPE) values ranged from 0.24 to 0.33 t ha−1, and 9% to 14%, respectively. Willmott's index of agreement (WI) was greater than or equal to 0.710 in model evaluation steps for three out of five provinces. The relatively low values of WI were found for provinces with relatively low inter-annual yield variability (i.e. Dak Lak and Dak Nong). Moreover, the model was successfully tested using remote sensing satellite and model-based gridded climate data: MAPE values were ≤ 12% and RMSE were ≤ 0.29 t ha−1. Such evaluation is important for long-term coffee productivity studies in these regions where long-term climate stations data are not readily available. The simple process-based model presented in this study could serve as a basis for developing an integrated seasonal climate-robusta coffee yield forecasting system, which would offer substantial benefits to coffee growers and industry through better supply chain management and preparedness for extreme climate events, and increased profitability. [ABSTRACT FROM AUTHOR]

• Microclimate and floral resources affect bee visit duration on coffee flowers. • Nectar caffeine concentration was an important predictor of bee visit duration. • Coffee floral availability was the main predictor for coffee pollen load on bees. • Shade trees do not detract from pollinator visitation to coffee. • Honeybees were the main visitors to coffee flowers in Puerto Rico. As agriculture expands to meet the needs of a growing global population, natural ecosystems are threatened by deforestation and habitat fragmentation. Tropical agroforestry systems offer a sustainable alternative to traditional agriculture by providing food for production while also supporting biodiversity and ecosystem services. Previous studies have shown that these systems may even improve crop pollination, but the mechanisms of how these improvements occur are still poorly understood. Using coffee as a focal crop, we explored how microclimatic conditions affected nectar traits (sugar and caffeine concentration) important for pollinator visitation. We also studied how microclimate, floral traits, floral availability at the coffee plant level, availability of floral resources provided by other plant species in the agroecosystem ("neighborhood floral availability"), and the presence of other bees affected the amount of time bees spent foraging on coffee flowers and the proportion of coffee pollen carried on their bodies. We explored these factors using the two dominant coffee species farmed on Puerto Rico, Coffea canephora and C. arabica , under sun and shade management. We found that high nectar sugar concentration and temperature were important predictors of short floral visits (<15s), while increased numbers of bees and open coffee flowers were important predictors of longer floral visits (16–180 seconds). High nectar caffeine concentration was an important predictor of longer visits on C. arabica flowers while the opposite was observed for C. canephora flowers. For both species, high coffee floral availability was the main predicting factor for the proportion of coffee pollen on the bees' bodies. Surprisingly, neither neighborhood floral availability nor the type of coffee plantation (agroforest/shade or sun) were important predictors of bee visitation. These results suggest non-coffee flowering plants in coffee plantations were neither competitors nor facilitators of coffee plants for pollinators. Additionally, most of the bees surveyed were carrying ≥80 % pollen from one species (C. arabica or C. canephora), likely resulting in little heterospecific pollen deposition between Coffea and non- Coffea flowers. Shade trees in coffee plantations do not detract from pollinator visitation to coffee flowers, suggesting that the provision of multiple ecological and wildlife conservation benefits by shade trees is not in conflict with a grower's ability to maximize the benefits of insect pollination on fruit production. [ABSTRACT FROM AUTHOR]

• New methods based on the sap flow allow estimating the actual plant transpiration. • The present work proposes a new methodology for estimating the CWSI for coffee. • A critical value of coffee CWSI allows estimating the moment to start irrigation. Measurements of water consumption by plants are not often used in irrigation management due to the high cost and difficulty of measurement, however new methods based on sap flow monitoring enable accurate estimation of plant transpiration. The objective of this work was to develop a sap flow sensor to reliably evaluate crop water stress index (CWSI sapflow) to diagnose water status of coffee plants in response to 3 cycles of water suppression and recovery, thus proposing a critical water stress index for conilon coffee plants (Coffea canephora). Sixteen potted coffee plants were randomly monitored under two water status treatments. In eight plants, the soil was watered and maintained at field capacity moisture (irrigated treatment) and the other eight plants were subjected to water stress by water withholding (non-irrigated treatment). The calibration of the sap flow sensor allowed the conception of the proposed crop water stress index, which was compared to leaf water potential, stomatal conductance, transpiration and net photosynthetic CO 2 assimilation rate. A coefficient based on actual transpiration was calculated to validate the crop water stress index. The sap flow sensor can be used for determining sap flow in conilon coffee plants, as well as elaborating a crop water stress index and estimating crop water status quickly and at relatively low cost. A critical value (0.4) for the crop water stress index (CWSI sapflow) in conilon coffee plants allows accurate scheduling the best time to initiate irrigation, avoiding physiological damage to the plant. [ABSTRACT FROM AUTHOR]

• Potentials for improved irrigation strategies in robusta coffee in Vietnam are investigated. • Variable irrigation amounts were applied depending on the province and rainfall patterns. • Irrigation water savings are achievable while maintaining/increasing current yield levels. • Water savings from 27 to 536 L tree−1 (30–590 m3 ha−1) depending on the province and year. • Province-specific improved irrigation management strategies in robusta coffee achievable. Robusta coffee is critically important for the economy and farmers of Vietnam, but also requires substantial irrigation leading to dwindling water resources. Developing clear recommendations for improved irrigation water management, while maintaining or increasing yield is therefore a key knowledge need for the coffee industry. We analyse 10-cropping-year data (2008/2009–2017/2018) of 558 farms across four major coffee-producing provinces in Vietnam's Central Highlands using CROPWAT and hierarchical Bayesian modelling to (1) identify irrigation requirements under different climatic conditions, and (2) investigate the potential for improved irrigation management strategies. In average rainfall years the majority of farmers in Dak Nong and Lam Dong supplied an equivalent of 455–909 L tree−1 (assuming 1100 plants ha−1) with corresponding average yields ranging from 2149 to 3177 kg ha−1. In Dak Lak and Gia Lai the predominant range was equivalent to 1364–1818 L tree-1 (corresponding average yields: 2190 to 3203 kg ha−1). In dry years more water was supplied through irrigation at various levels depending on the province: varying between 1364–1818 L tree−1 in Dak Lak and Gia Lai, and 909–1364 L tree−1 in Dak Nong and Lam Dong. Our study also shows that irrigation water can be reduced by 273–536 L tree−1 (300–590 m3 ha−1) annually from the current levels in average rainfall years while still achieving average yield levels greater than 3000 kg ha−1. In dry years reductions of 27–218 L tree−1 (30–240 m3 ha−1) are possible. With adequate management of the key crop practices affecting coffee yields, substantial water savings at the provincial scale could be achieved. Thus, our findings could serve as a basis for province-specific irrigation water management in robusta coffee farms that will not only reduce overall water use, but also potentially maintain satisfactory yield levels. [ABSTRACT FROM AUTHOR]