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Coffee outturn can be defined as the ratio between the harvested coffee and its respective processed grains. This character is greatly influenced by genotypic and environmental effects, and in breeding programs your analysis is costly and time-consuming. In this sense, the use of an outturn index to estimate coffee yield on experimental plots is a desirable measure aiming at reducing resources and time in postharvest evaluations. Thus, the present study aimed to evaluate the accuracy of the use of an outturn index equal to 4.0, in the estimation of Conilon coffee grains production. This index indicates that four kilograms of harvested fruit would be needed to obtain one kilogram of processed grains. Based on the average of 157 genotypes conducted in three trials and four harvests, we evaluated the relationship between harvested fruits and processed grains (FcBe), the observed (OGY), and the estimated grain yield per plant (EGY) based on FcBe equal to 4.0 (an outturn index). Descriptive statistics, adequation test for EGY, and the coincidence of occurrence of genotypes observations relating to the top 20% of all observations of OGY and EGY. In the estimation of grain yield in Conilon, the use of FcBe equal to 4.0 showed high precision in the average of the analyzed trials. However, further studies should be conducted to elucidate the effects of climate variables on the yield of Conilon coffee, especially in atypical crop years. Thus, the use of an outturn index becomes interesting in cases where the number of genotypes to be evaluated is very large and a screening of the promising ones is desirable Made available in DSpace on 2022-03-11T15:01:54Z (GMT). No. of bitstreams: 1 conilon-coffee-outturn.pdf: 738123 bytes, checksum: 8a150265dd168bbd444f2de902f84685 (MD5) Previous issue date: 2022

The specialty coffee market has grown significantly in the past decades and has several cultivars with productive potential. The objective of this study was to evaluate the sensory profile of the beverage produced from Coffea arabica L. genotypes based on postharvest processing and to identify cultivars with the greatest genetic potential for coffee cultivation in the city of Araponga, Minas Gerais, Brazil. The experiment was a randomized complete block design with two replicates and 11 genotypes with different levels of resistance to rust. The sensory profile demonstrated an interaction between the genotype and the processing technique. Five of the genotypes presented total scores above 85 points according to the SCAA protocol. Moreover, two of these genotypes yielded heightened sensory notes after undergoing dry processing. The selection of coffee genotypes should consider the level of technology involved in the drying of the coffee beans, which preserves the potential quality of the beverage. Made available in DSpace on 2019-12-30T18:10:11Z (GMT). No. of bitstreams: 1 SensoryqualityofcoffeaarabicaL.genotypes.pdf: 675494 bytes, checksum: a5dac272c36d53f2319aa814a5b3557e (MD5) Previous issue date: 2019

The use of single nucleotide polymorphism (SNP) molecular markers has provided advances in selection methodologies used in breeding programs of different crops, reducing cost and time of cultivar release. Despite the great economic and social importance of Coffea arabica, studies with SNP markers are scarce and a small number of SNP are available for this species, when compared with other crops of agronomic mportance. Thus, the objective of this study was to identify and validate SNP molecular markers for the species Coffea arabica and to introduce these markers to genetic breeding by means of an accurate analysis of the diversity and genetic structure of breeding populations of this species. After quality filtering, 11,187 SNP markers were selected from the coffee population obtained from crosses between the genotypes Catuaí and Híbrido de Timor. A great number of markers were distributed in the 11 chromosomes, within transcribed regions, and were used to estimate the genetic dissimilarity among the individuals of the breeding population. Dendrogram analysis and a Bayesian approach demonstrated the formation of two groups and the discrimination of all genotypes evaluated. The expressive number of SNP molecular markers distributed throughout C. arabica genome was efficient to discriminate all the accessions evaluated in the experiment, clustering them according to their genealogies. This work identified mixtures within the progenies. The genotyping data also provided detailed information about the parental genotypes and led to the identification of new candidate parents to be introduced to the breeding program. The study discussed population structure and its consequence in obtaining improved varieties of C. arabica. Made available in DSpace on 2017-12-08T23:22:06Z (GMT). No. of bitstreams: 1 Populationstructureandgeneticdiversity.pdf: 1934949 bytes, checksum: 2f34a0809e424a7937076856a558ffd2 (MD5) Previous issue date: 2017-12-08

Selecting superior genotypes is facilitated by marker-assisted selection (MAS), which is particularly suitable for transferring disease resistance alleles because it nullifies environmental effects and allows selection of resistant individuals in the absence of the pathogen or race, enabling preventive breeding. Molecular markers linked to two major genes (SH3 and SH?), conferring resistance to coffee rust, and those linked to the Ck-1 gene, conferring resistance to coffee berry disease (CBD), have previously been identified. These markers were validated and used in a progeny of crosses between Indian selections with Coffea arabica cultivars. Eleven resistant individuals homozygous for SH3 were identified by MAS. Of these, seven carry SH? from Híbrido de Timor and the gene introduced from Coffea liberica (SH3). SH? was characterized as derived from Coffea canephora. Thus, it was possible to identify C. arabica genotypes carrying important genes for rust resistance introgressed from other coffee species. MAS also allowed identification of sources of CBD resistance for use in preventive breeding for resistance to this serious disease. Using two validated molecular markers, two coffee plants carrying Ck-1 were identified: the UFV 328-60 genotype (F2) was resistant and homozygous based on both molecular markers but exhibited no markers related to SH3 and SH?, and the UFV 317- 12 genotype (F1) was resistant and homozygous but resistant and heterozygous based on CBD-Sat207 and CBD-Sat235, respectively. Along with possessing Ck- 1, the latter carries SH?. Overall, plants carrying different genes for resistance to rust and CBD were identified. These plants are important sources for gene pyramiding in breeding programs aimed at multiple and durable resistance.

New cultivars are released every year to meet market demands. However, in species with a narrow genetic base, such as Coffea arabica, the cultivars are closely related and phenotypically similar. This hinders the accurate discrimination of genotypes sing morphological descriptors in distinctness, uniformity, and stability (DUS) testing, which is required for the registration and protection of new cultivars. In this sense, molecular markers are an auxiliary tool for accurate and precise discrimination of cultivars. This study aimed to verify the informative capacity and effectiveness of a molecular marker set to discriminate among C. arabica varieties, create a database of DNA profiles and allele frequencies, analyze the genetic diversity in this collection, and explore genetic kinships. Thirty-four C. arabica cultivars/progenies, which belong to the Brazilian Cultivar Trial, were analyzed using 31 microsatellite markers. Markers with weak bands were removed, and of the remaining, 74.07% were polymorphic and revealed 47 alleles. The obtained molecular profiles revealed segregation between and within cultivars/progenies, and genetic variability was observed between all the cultivars/progenies. Sixteen markers were selected for dendrogram construction and for fingerprinting analysis of the cultivars. The ability of these markers to detect varietal mixture and analyze diversity between and within cultivars was also discussed in detail. The results demonstrated the effectiveness of markers in distinguishing related genotypes from those with similar phenotypic traits. This biotechnological tool will assist breeders in DUS testing of cultivars.

Coffee tree is a shrub with dimorphic branches. The orthotropic stem grows vertically with two near-horizontal plagiotropic branches, per node, in opposite phyllotaxy. The consecutive nodes of the orthotropic stem are organized in parastichies. We report here mutant plants of Coffea arabica with triple plagiotropic branch, resulted from the whorled phyllotaxy of the orthotropic stem. In mutant plants three plagiotropic branches in the same node are separated by angles of approximately 120o, while in normal plants two plagiotropic branches in the same node are separated by angles of approximately 180o. In mutant plants the angles of the parastichies increase approximately 50o clockwise between consecutive nodes, while in normal plants the angles increase approximately 87o. The plant architecture is changed. The triple plagiotropic branch is a putative mutant with potential to be explored in coffee breeding programs. The hypotheses for the origin of the mutation and the research perspectives are discussed. Made available in DSpace on 2017-12-08T23:20:41Z (GMT). No. of bitstreams: 1 Tripleplagiotropicbranchincoffee.pdf: 1082488 bytes, checksum: d1c695b3f5ec77d98016f1f28434324c (MD5) Previous issue date: 2017-12-08

Made available in DSpace on 2017-09-14T00:12:22Z (GMT). No. of bitstreams: 1 Herbaceouslegumesintecropping.pdf: 80399 bytes, checksum: 1f2368a3e2638164261a1a5f221c8747 (MD5) Previous issue date: 2017-09-12

The production of specialty coffees is the main criterion to add value to the product. However, there is a lack of information regarding genetic variability of C. arabica for quality improvement. The aim of this study was to analyze the genetic divergence among Coffee arabica genotypes regarding the potential cup quality, possible limitations and their potential use in breeding programs to improve quality. We evaluated 101 coffee genotypes from the Germplasm Active Bank of Empresa de Pesquisa Agropecuária de Minas Gerais, covering different groups of genealogical origin. A randomized block design was used with two replications. Sensory analysis of the beverage was performed by two tasters per sample (repetition), using the Cup of Excellence methodology enhanced by the Brazilian Specialty Coffee Association. The attributes assessed were clean cup, sweetness, acidity, body, flavor, aftertaste, balance, overall and final score. K-means and Ward clustering methods were used to study the genotypes divergence. Based on sensory scores, the formed clusters differed with regards to all sensory characteristics (P ≤ 0.01). Three K-means clusters were formed among 40, 45 and 16 genotypes, with final average scores of 80.11, 83.17 and 87.56 points, respectively. Ninety percent of the genotypes evaluated have the genetic potential to produce specialty coffees. The observed divergence indicates the potential of genetic gains for quality and the Híbrido de Timor germplasm can be used for this purpose.

Specialty coffees can be differentiated in various ways, including the environmental conditions in which they are produced and the sensory composition of the drink. This study aimed to evaluate the effect of altitude, slope exposure and fruit color on the sensory attributes of cafes of the region of Matas de Minas. Sampling points were georeferenced in four altitude ranges (< 700 m; 700 < x> 825 m, 825 < x < 950 m and > 950 m) of the coffee crop; two fruit colors of var. Catuaí (yellowand red); and two slope exposures (North-facing and South-facing). Coffee fruit at the cherry stage were processed andsubmitted to sensory analysis. The sensory attributes evaluated were overall perception, clean cup, balance, aftertaste, sweetness, acidity , body and flavor, which made up the final score. The scores were examined by ANOVA and means werecompared by the Tukey test (p < 0.05). From the sensory standpoint, coffee fruits of both colors are similar, as well as the cof fees from both slope exposures when these factors were analyzed separately . However , at higher altitudes, Y ellow Catuaí produces coffees with better sensory quality . Similarly , coffees from North-facing slopes, at higher altitudes produce better quality cup. The altitude is the main factor that interferes with coffee quality in the area. All factors together contribute tothe final quality of the beverage produced in the region of Matas de Minas.

Coffee leaf rust (CLR) caused by Hemileia vastatrix Berk. et Br. is one of the major Coffea arabica diseases world-wide. CLR resistance has been attributed to at least nine dominant genes, as single or in combination. We present an inheritance study and mapping loci involved in the Híbrido de Timor (HDT) UFV 443-03 resistance to race I, race II, and pathotype 001 of H. vastatrix . Molecular markers were used to ascertain the phenotypic results and to map the putative resistance loci. For all tree isolates, the inheritance study indicated that the resistance of HDT UFV 443-03 is conditioned by two independent dominant loci or by three independent loci (two dominant and one recessive). Molecular marker analyses ascertained that the resistance of HDT UFV 443-03 to race II is conditioned by at least two independent dominant loci, while the resistance to race I and pathotype 001 is conditioned by at least four independent dominant loci. Gene pyramiding might result in a cultivar with durable resistance; however, it is Difficult to distinguish between plants with one or more resistance genes due to epistatic effects. Molecular markers linked to these genes were indicated for marker-assisted selection, as it is an efficient breeding alternative for CLR resistance with no such epistatic effects.

Microsatellite markers (SSR) have broad utility in genetic studies due to a high rate of polymor-phisms, a codominant nature and multiallelism. EST?SSRs are markers derived from the expressed sequences of a genome and represent transcribed genes. Despite the importance of the genus Coffea , only a small number of EST?SSR markers are currently available. Thus, this study was designed to mine and develop a new set of EST?SSR markers from the Brazilian Coffee Genome Project. We investigated 130,792 expressed sequence tags (ESTs), from which 24,031 DNA sequences with microsatellites were identified. After stability and amplification testing, 101 new EST?SSR markers were developed and analyzed in different coffee species. The average rate of transferability was 88 %, showing that these markers are useful in genetic studies across the genus Coffea. Polymorphism levels and the degree of diversity were consistent with the evolutionary history of the species. All coffee genotypes were discriminated, even the C. arabica genotypes that have known narrow genetic basis. It was also possible to locate 14 EST? SSRs into different linkage groups of the C. arabica genetic map, which demonstrate that these markers can be useful in QTL mapping studies and in molecular-assisted selection.

The use of molecular markers to study genetic diversity represents a breakthrough in this area, because of the increase in polymorphism levels and phenotypic neutrality. Codominant markers, such as microsatellites (SSR), are sensitive enough to distinguish the heterozygotes in genetic studies. Despite this advantage, there are some studies that ignore this feature and work with encoded data because of the simplicity of the evaluation, existence of polyploids and need for the combined analysis of different types of molecular markers. Thus, our study aims to investigate the consequences of these encodings on simulated and real data. In addition, we suggest an alternative analysis for genetic evaluations using different molecular markers. For the simulated data, we proposed the following two scenarios: the first uses SNP markers, and the second SSR markers. For real data, we used the SSR genotyping data from Coffea canephora accessions maintained in the Embrapa Germplasm Collection. The genetic diversity was studied using cluster analysis, the dissimilarity index, and the Bayesian approach implemented in the STRUCTURE software. For the simulated data, we observed a loss of genetic information to the encoded data in both scenarios. The same result was observed in the coffee studies. This loss of information was discussed in the context of a plantbreeding program, and the consequences were weighted to germplasm evaluations and the selection of parents for hybridization. In the studies that involved different types of markers, an alternative to the combined analysis is discussed, where the informativeness, coverage and quality of markers are weighted in the genetic diversity studies. Made available in DSpace on 2015-03-27T06:24:41Z (GMT). No. of bitstreams: 1 Flavio.cpatsa.2014.pdf: 1503662 bytes, checksum: ebd89b78d532d3aa7f5329d73908e3f8 (MD5) Previous issue date: 2014-03-07

Over the past three decades, molecular marker studies reachedextraordinary advances, especially for sequencing and bioinformatics techniques.Marker-assisted selectionbecamepart of the breeding program routines of important seed companies, in order to accelerate and optimize the cultivar developing processes. Private seed companies increasingly use marker-assisted selection, especially for the species of great importance to the seed market, e.g. corn, soybean, cotton, and sunflower. In the Brazilian public institutions few breeding programs use it efficiently.The possible reasons are: lack of know-how, lack of appropriate laboratories, few validated markers, high cost, and lack of urgency in obtaining cultivars. In this article we analyze the use and the constraints of marker-assisted selection in plant breeding programs of Brazilian public institutes Made available in DSpace on 2020-10-03T09:16:22Z (GMT). No. of bitstreams: 1 Sakiyama-et-al-2014.pdf: 287423 bytes, checksum: 1e92bf0be6ffa39ed9ed583db9601ac9 (MD5) Previous issue date: 2014

The aim of this study was to evaluate the cultivation of perennial herbaceous legumes on weed control and yield of the coffee crop in the Cerrado. The experimental design was a randomized complete block with four replications. The 10 treatments tested in factorial 4 × 2 + 2, were four legumes: forage peanut (Arachis pintoi), hybrid Java (Macrotyloma axillare), perennial soybean (Neonotonia wightii) and wild ground nut (Calopogonium mucunoides); two forms in the interrows of coffee plants with two and three rows of legumes spaced by 0.50 m and 0.25 m, respectively; and two additional treatments consisted of hand weeding with hoe and chemical control with glyphosate. The hybrid Java and wild ground nut in the first year and the hybrid Java and perennial soybean in the second year, all followed by forage peanut, promoted lower density and biomass of the weeds. The wild ground nut in the first year and forage peanut in the second year showed higher soil cover. The hybrid Java had its highest biomass production in two years, and wild ground nut being higher in the first year. The cultivation of perennial herbaceous legumes promoted weed control without interfering in the productivity of the coffee crop. Made available in DSpace on 2017-09-08T00:13:21Z (GMT). No. of bitstreams: 1 Cultivationofperennial.pdf: 117575 bytes, checksum: dd98932e253d6f0cb629ba1d3073ec18 (MD5) Previous issue date: 2017-09-06

Coffee leaf rust caused by the fungus Hemileia vastatrix causes considerable economic losses for coffee producers. Although agrochemical products can provide sufficient disease control, the use of resistant cultivars is a safer alternative. This resistance may be constrained by one or a few genetic factors, mainly those found in material originating from interspecific hybrids. In this study, the genetic analysis of an F2 population consisting of 224 plants derived from a crossing of Híbrido de Timor UFV 427-15 (resistant) with Catuaí Amarelo IAC 30 (susceptible) showed that a dominant gene confers the resistance of coffee to race II of H. vastatrix. From a genetic map saturated with 25 amplified fragment length polymorphism (AFLP) markers linked to the resistance gene, we developed a high-density genetic map with six sequence-characterized amplified region (SCAR) markers delimiting a chromosomal region of 9.45 cM and flanking the dominant gene at 0.7 and 0.9 cM. This is the first saturated and high-density genetic map obtained from this region containing the resistance gene. The results of this study are of great importance for the introduction of molecular markers for marker-assisted selection; they will also facilitate studies related to the cloning, structure, and function of race-specific genes involved in the resistance of coffee trees to H. vastatrix.

Thirty-three coffee SSR primers from enriched genomic library with (GT)15 and (AGG)10 repeats were analyzed in 24 coffee tree accessions. Twenty-two primers were polymorphic among accessions; the number of alleles ranged from 2 to 13, with the mean number of 5.1 alleles per primer. PIC values ranged from 0.08 to 0.79. The highest mean PIC values were found for C. canephora (0.46), and the lowest values for C. arabica (0.22) and triploids (0.22) accessions. The polymorphic SSR markers used in this study were useful for genetic fingerprinting in the coffee tree, especially in the C. canephora and the leaf rust resistant arabica cultivars.

Made available in DSpace on 2011-04-09T22:28:01Z (GMT). No. of bitstreams: 1 Assessmentofestssr.pdf: 389003 bytes, checksum: f273930646d347b5cc786604c4526c5a (MD5) Previous issue date: 2011-03-10