Genetic diversity and inter-gene pool introgression of Mesoamerican Diversity Panel in common beans.

Brazil is among the largest producers and consumers of common bean (Phaseolus vulgaris L.) and can be considered a secondary center of diversity for the species. The aim of this study was to estimate the genetic diversity, population structure, and relationships among 288 common bean accessions in an American Diversity Panel (ADP) genotyped with 4,042 high-quality single nucleotide polymorphisms (SNPs). The results showed inter-gene pool hybridization (hybrids) between the two main gene pools (i.e., Mesoamerican and Andean), based on principal component analysis (PCA), discriminant analysis of principal components (DAPC), and STRUCTURE analysis. The genetic diversity parameters showed that the Mesoamerican group has higher values of diversity and allelic richness in comparison with the Andean group. Considering the optimal clusters (K), clustering was performed according to the type of grain (i.e., market group), the institution of origin, the period of release, and agronomic traits. A new subset was selected and named the Mesoamerican Diversity Panel (MDP), with 205 Mesoamerican accessions. Analysis of molecular variance (AMOVA) showed low genetic variance between the two panels (i.e., ADP and MDP) with the highest percentage of the limited variance among accessions in each group. The ADP showed occurrence of high genetic differentiation between populations (i.e., Mesoamerican and Andean) and introgression between gene pools in hybrids based on a set of diagnostic SNPs. The MDP showed better linkage disequilibrium (LD) decay. The availability of genetic variation from inter-gene pool hybridizations presents a potential opportunity for breeders towards the development of superior common bean cultivars.

Genome-wide association mapping reveals new loci associated with light-colored seed coat at harvest and slow darkening in carioca beans.

BACKGROUND: Common bean (Phaseolus vulgaris L.) is a legume whose grain can be stored for months, a common practice among Brazilian growers. Over time, seed coats become darker and harder to cook, traits that are undesirable to consumers, who associate darker-colored beans with greater age. Like commercial pinto and cranberry bean varieties, carioca beans that have darker seeds at harvest time and after storage are subject to decreased market values. RESULTS: The goal of our study was to identify the genetic control associated with lightness of seed coat color at harvest (HL) and with tolerance to post-harvest seed coat darkening (PHD) by a genome-wide association study. For that purpose, a carioca diversity panel previously validated for association mapping studies was used with 138 genotypes and 1,516 high-quality SNPs. The panel was evaluated in two environments using a colorimeter and the CIELAB scale. Shelf storage for 30 days had the most expressive results and the L* (luminosity) parameter led to the greatest discrimination of genotypes. Three QTL were identified for HL, two on chromosome Pv04 and one on Pv10. Regarding PHD, results showed that genetic control differs for L* after 30 days and for the ΔL* (final L*-initial L*); only ΔL* was able to properly express the PHD trait. Four phenotypic classes were proposed, and five QTL were identified through six significant SNPs. CONCLUSIONS: Lightness of seed coat color at harvest showed an oligogenic inheritance corroborated by moderate broad-sense heritability and high genotypic correlation among the experiments. Only three QTL were significant for this trait - two were mapped on Pv04 and one on Pv10. Considering the ΔL, six QTL were mapped on four different chromosomes for PHD. The same HL QTL at the beginning of Pv10 was also associated with ΔL* and could be used as a tool in marker-assisted selection. Several candidate genes were identified and may be useful to accelerate the genetic breeding process.

Genome-Wide Association Study Reveals Genomic Regions Associated with Fusarium Wilt Resistance in Common Bean.

Fusarium wilt (Fusarium oxysporum f. sp. phaseoli, Fop) is one of the main fungal soil diseases in common bean. The aim of the present study was to identify genomic regions associated with Fop resistance through genome-wide association studies (GWAS) in a Mesoamerican Diversity Panel (MDP) and to identify potential common bean sources of Fop's resistance. The MDP was genotyped with BARCBean6K_3BeadChip and evaluated for Fop resistance with two different monosporic strains using the root-dip method. Disease severity rating (DSR) and the area under the disease progress curve (AUDPC), at 21 days after inoculation (DAI), were used for GWAS performed with FarmCPU model. The p-value of each SNP was determined by resampling method and Bonferroni test. For UFV01 strain, two significant single nucleotide polymorphisms (SNPs) were mapped on the Pv05 and Pv11 for AUDPC, and the same SNP (ss715648096) on Pv11 was associated with AUDPC and DSR. Another SNP, mapped on Pv03, showed significance for DSR. Regarding IAC18001 strain, significant SNPs on Pv03, Pv04, Pv05, Pv07 and on Pv01, Pv05, and Pv10 were observed. Putative candidate genes related to nucleotide-binding sites and carboxy-terminal leucine-rich repeats were identified. The markers may be important future tools for genomic selection to Fop disease resistance in beans.

Genome-wide association mapping reveals race-specific SNP markers associated with anthracnose resistance in carioca common beans.

Brazil is the largest consumer of dry edible beans (Phaseolus vulgaris L.) in the world, 70% of consumption is of the carioca variety. Although the variety has high yield, it is susceptible to several diseases, among them, anthracnose (ANT) can lead to losses of up to 100% of production. The most effective strategy to overcome ANT, a disease caused by the fungus Colletotrichum lindemuthianum, is the development of resistant cultivars. For that reason, the selection of carioca genotypes resistant to multiple ANT races and the identification of loci/markers associated with genetic resistance are extremely important for the genetic breeding process. Using a carioca diversity panel (CDP) with 125 genotypes and genotyped by BeadChip BARCBean6K_3 and a carioca segregating population AM (AND-277 × IAC-Milênio) genotyped by sequencing (GBS). Multiple interval mapping (MIM) and genome-wide association studies (GWAS) were used as mapping tools for the resistance genes to the major ANT physiological races present in the country. In general, 14 single nucleotide polymorphisms (SNPs) showed high significance for resistance by GWAS, and loci associated with multiple races were also identified, as the Co-3 locus. The SNPs ss715642306 and ss715649427 in linkage disequilibrium (LD) at the beginning of chromosome Pv04 were associated with all the races used, and 16 genes known to be related to plant immunity were identified in this region. Using the resistant cultivars and the markers associated with significant quantitative resistance loci (QRL), discriminant analysis of principal components (DAPC) was performed considering the allelic contribution to resistance. Through the DAPC clustering, cultivar sources with high potential for durable anthracnose resistance were recommended. The MIM confirmed the presence of the Co-14 locus in the AND-277 cultivar which revealed that it was the only one associated with resistance to ANT race 81. Three other loci were associated with race 81 on chromosomes Pv03, Pv10, and Pv11. This is the first study to identify new resistance loci in the AND-277 cultivar. Finally, the same Co-14 locus was also significant for the CDP at the end of Pv01. The new SNPs identified, especially those associated with more than one race, present great potential for use in marker-assisted and early selection of inbred lines.

Angular Leaf Spot Resistance Loci Associated With Different Plant Growth Stages in Common Bean.

Angular leaf spot (ALS) is a disease that causes major yield losses in the common bean crop. Studies based on different isolates and populations have already been carried out to elucidate the genetic mechanisms of resistance to ALS. However, understanding of the interaction of this resistance with the reproductive stages of common bean is lacking. The aim of the present study was to identify ALS resistance loci at different plant growth stages (PGS) by association and linkage mapping approaches. An BC2F3 inter-gene pool cross population (AND 277 × IAC-Milênio - AM population) profiled with 1,091 SNPs from genotyping by sequencing (GBS) was used for linkage mapping, and a carioca diversity panel (CDP) genotyped by 5,398 SNPs from BeadChip assay technology was used for association mapping. Both populations were evaluated for ALS resistance at the V2 and V3 PGSs (controlled conditions) and R8 PGS (field conditions). Different QTL (quantitative trait loci) were detected for the three PGSs and both populations, showing a different quantitative profile of the disease at different plant growth stages. For the three PGS, multiple interval mapping (MIM) identified seven significant QTL, and the Genome-wide association study (GWAS) identified fourteen associate SNPs. Several loci validated regions of previous studies, and Phg-1, Phg-2, Phg-4, and Phg-5, among the 5 loci of greatest effects reported in the literature, were detected in the CDP. The AND 277 cultivar contained both the Phg-1 and the Phg-5 QTL, which is reported for the first time in the descendant cultivar CAL143 as ALS10.1UC. The novel QTL named ALS11.1AM was located at the beginning of chromosome Pv11. Gene annotation revealed several putative resistance genes involved in the ALS response at the three PGSs, and with the markers and loci identified, new specific molecular markers can be developed, representing a powerful tool for common bean crop improvement and for gain in ALS resistance.

Mapping QTLs for drought tolerance in a SEA 5 x AND 277 common bean cross with SSRs and SNP markers

Abstract The common bean is characterized by high sensitivity to drought and low productivity. Breeding for drought resistance in this species involves genes of different genetic groups. In this work, we used a SEA 5 x AND 277 cross to map quantitative trait loci associated with drought tolerance in order to assess the factors that determine the magnitude of drought response in common beans. A total of 438 polymorphic markers were used to genotype the F8 mapping population. Phenotyping was done in two greenhouses, one used to simulate drought and the other to simulate irrigated conditions. Fourteen traits associated with drought tolerance were measured to identify the quantitative trait loci (QTLs). The map was constructed with 331 markers that covered all 11 chromosomes and had a total length of 1515 cM. Twenty-two QTLs were discovered for chlorophyll, leaf and stem fresh biomass, leaf biomass dry weight, leaf temperature, number of pods per plant, number of seeds per plant, seed weight, days to flowering, dry pod weight and total yield under well-watered and drought (stress) conditions. All the QTLs detected under drought conditions showed positive effects of the SEA 5 allele. This study provides a better understanding of the genetic inheritance of drought tolerance in common bean.

Mapping QTLs for drought tolerance in a SEA 5 x AND 277 common bean cross with SSRs and SNP markers.

The common bean is characterized by high sensitivity to drought and low productivity. Breeding for drought resistance in this species involves genes of different genetic groups. In this work, we used a SEA 5 x AND 277 cross to map quantitative trait loci associated with drought tolerance in order to assess the factors that determine the magnitude of drought response in common beans. A total of 438 polymorphic markers were used to genotype the F8 mapping population. Phenotyping was done in two greenhouses, one used to simulate drought and the other to simulate irrigated conditions. Fourteen traits associated with drought tolerance were measured to identify the quantitative trait loci (QTLs). The map was constructed with 331 markers that covered all 11 chromosomes and had a total length of 1515 cM. Twenty-two QTLs were discovered for chlorophyll, leaf and stem fresh biomass, leaf biomass dry weight, leaf temperature, number of pods per plant, number of seeds per plant, seed weight, days to flowering, dry pod weight and total yield under well-watered and drought (stress) conditions. All the QTLs detected under drought conditions showed positive effects of the SEA 5 allele. This study provides a better understanding of the genetic inheritance of drought tolerance in common bean.

Genome-Wide Association Studies of Anthracnose and Angular Leaf Spot Resistance in Common Bean (Phaseolus vulgaris L.).

The common bean (Phaseolus vulgaris L.) is the world's most important legume for human consumption. Anthracnose (ANT; Colletotrichum lindemuthianum) and angular leaf spot (ALS; Pseudocercospora griseola) are complex diseases that cause major yield losses in common bean. Depending on the cultivar and environmental conditions, anthracnose and angular leaf spot infections can reduce crop yield drastically. This study aimed to estimate linkage disequilibrium levels and identify quantitative resistance loci (QRL) controlling resistance to both ANT and ALS diseases of 180 accessions of common bean using genome-wide association analysis. A randomized complete block design with four replicates was performed for the ANT and ALS experiments, with four plants per genotype in each replicate. Association mapping analyses were performed for ANT and ALS using a mixed linear model approach implemented in TASSEL. A total of 17 and 11 significant statistically associations involving SSRs were detected for ANT and ALS resistance loci, respectively. Using SNPs, 21 and 17 significant statistically associations were obtained for ANT and angular ALS, respectively, providing more associations with this marker. The SSR-IAC167 and PvM95 markers, both located on chromosome Pv03, and the SNP scaffold00021_89379, were associated with both diseases. The other markers were distributed across the entire common bean genome, with chromosomes Pv03 and Pv08 showing the greatest number of loci associated with ANT resistance. The chromosome Pv04 was the most saturated one, with six markers associated with ALS resistance. The telomeric region of this chromosome showed four markers located between approximately 2.5 Mb and 4.4 Mb. Our results demonstrate the great potential of genome-wide association studies to identify QRLs related to ANT and ALS in common bean. The results indicate a quantitative and complex inheritance pattern for both diseases in common bean. Our findings will contribute to more effective screening of elite germplasm to find resistance alleles for marker-assisted selection in breeding programs.

Developing a common bean core collection suitable for association mapping studies.

Because of the continuous introduction of germplasm from abroad, some collections have a high number of accessions, making it difficult to explore the genetic variability present in a germplasm bank for conservation and breeding purposes. Therefore, the aim of this study was to quantify and analyze the structure of genetic variability among 500 common bean accessions to construct a core collection. A total of 58 SSRs were used for this purpose. The polymorphism information content (PIC) in the 180 common bean accessions selected to compose the core collection ranged from 0.17 to 0.86, and the discriminatory power (DP) ranged from 0.21 to 0.90. The 500 accessions were clustered into 15 distinct groups and the 180 accessions into four distinct groups in the Structure analysis. According to analysis of molecular variance, the most divergent accessions comprised 97.2% of the observed genetic variability present within the base collection, confirming the efficiency of the selection criterion. The 180 selected accessions will be used for association mapping in future studies and could be potentially used by breeders to direct new crosses and generate elite cultivars that meet current and future global market needs.

Occurrence of isoflavonoids in Brazilian common bean germplasm (Phaseolus vulgaris L.).

Common bean (Phaseolus vulgaris) is present in the daily diet of various countries and, as for other legumes, has been investigated for its nutraceutical potential. Thus, 16 genotypes from different gene pools, representing seven types of seed coats and different responses to pathogens and pests, were selected to verify their isoflavone contents. The isoflavonoids daidzein and genistein and the flavonols kaempferol, myricetin, and quercetin were found. Grains of the black type showed the highest concentrations of isoflavonoids and were the only ones to exhibit daidzein. IAC Formoso, with high protein content and source of resistance to anthracnose, showed the greatest concentration of genistein, representing around 11% of the content present in soybean, as well as high levels of kaempferol. Arc 1, Raz 55, and IAC Una genotypes showed high content of coumestrol. The results suggest the use of IAC Formoso to increase the nutraceutical characteristics in common bean.

Induction of ferritin synthesis by water deficit and iron excess in common bean (Phaseolus vulgaris L.).

Ferritins are molecules for iron storage present in most living beings. In plants, ferritin is an essential iron homeostasis regulator and therefore plays a fundamental role in control of iron induced by oxidative stress or by excess of iron ions. Ferritin gene expression is modulated by various environmental factors, including the intensity of drought, cold, light and pathogenic attack. Common bean, one of the most important species in the Brazilian diet, is also affected by insufficiency or lack of water. Thus, the present study was conducted for the purpose of determining the levels of expression of ferritins transcripts in leaf tissues of three common bean cultivars (BAT 477, Carioca Comum and IAC-Diplomata) under osmotic shock caused by polyethylene glycol 6000 and by iron excess. The expression of three ferritins genes (PvFer1, PvFer2 and PvFer3), determined by quantitative PCR, indicated a difference in the expression kinetics among the cultivars. All the ferritin genes were actively transcribed under iron excess and water deficit conditions. The cultivars most responsive to treatments were BAT 477 and IAC-Diplomata. All the cultivars responded to treatments. Nevertheless, the ferritin genes were differentially regulated according to the cultivars. Analysis of variance indicated differences among cultivars in expression of the genes PvFer1 and PvFer3. Both genes were most responsive to treatments. This result suggests that ferritin genes may be functionally important in acclimatization of common bean under iron excess or water deficit conditions.

Increasing the density of markers around a major QTL controlling resistance to angular leaf spot in common bean.

Angular leaf spot (ALS) causes major yield losses in the common bean (Phaseolus vulgaris L.), an important protein source in the human diet. This study describes the saturation around a major quantitative trait locus (QTL) region, ALS10.1, controlling resistance to ALS located on linkage group Pv10 and explores the genomic context of this region using available data from the P. vulgaris genome sequence. DArT-derived markers (STS-DArT) selected by bulk segregant analysis and SCAR and SSR markers were used to increase the resolution of the QTL, reducing the confidence interval of ALS10.1 from 13.4 to 3.0 cM. The position of the SSR ATA220 coincided with the maximum LOD score of the QTL. Moreover, a new QTL (ALS10.2(UC)) was identified at the end of the same linkage group. Sequence analysis using the P. vulgaris genome located ten SSRs and seven STS-DArT on chromosome 10 (Pv10). Coincident linkage and genome positions of five markers enabled the definition of a core region for ALS10.1 spanning 5.3 Mb. These markers are linked to putative genes related to disease resistance such as glycosyl transferase, ankyrin repeat-containing, phospholipase, and squamosa-promoter binding protein. Synteny analysis between ALS10.1 markers and the genome of soybean suggested a dynamic evolution of this locus in the common bean. The present study resulted in the identification of new candidate genes and markers closely linked to a major ALS disease resistance QTL, which can be used in marker-assisted selection, fine mapping and positional QTL cloning.

Mapping of angular leaf spot resistance QTL in common bean (Phaseolus vulgaris L.) under different environments.

BACKGROUND: Common bean (Phaseolus vulgaris L.) is the most important grain legume for human diet worldwide and the angular leaf spot (ALS) is one of the most devastating diseases of this crop, leading to yield losses as high as 80%. In an attempt to breed resistant cultivars, it is important to first understand the inheritance mode of resistance and to develop tools that could be used in assisted breeding. Therefore, the aim of this study was to identify quantitative trait loci (QTL) controlling resistance to ALS under natural infection conditions in the field and under inoculated conditions in the greenhouse. RESULTS: QTL analyses were made using phenotypic data from 346 recombinant inbreed lines from the IAC-UNAxCAL 143 cross, gathered in three experiments, two of which were conducted in the field in different seasons and one in the greenhouse. Joint composite interval mapping analysis of QTLxenvironment interaction was performed. In all, seven QTLs were mapped on five linkage groups. Most of them, with the exception of two, were significant in all experiments. Among these, ALS10.1DG,UC presented major effects (R2 between 16%-22%). This QTL was found linked to the GATS11b marker of linkage group B10, which was consistently amplified across a set of common bean lines and was associated with the resistance. Four new QTLs were identified. Between them the ALS5.2 showed an important effect (9.4%) under inoculated conditions in the greenhouse. ALS4.2 was another major QTL, under natural infection in the field, explaining 10.8% of the variability for resistance reaction. The other QTLs showed minor effects on resistance. CONCLUSIONS: The results indicated a quantitative inheritance pattern of ALS resistance in the common bean line CAL 143. QTL x environment interactions were observed. Moreover, the major QTL identified on linkage group B10 could be important for bean breeding, as it was stable in all the environments. Thereby, the GATS11b marker is a potential tool for marker assisted selection for ALS resistance.

Tamanho de grão comercial em cultivares de feijoeiro / Commercial grain size in common bean cultivars

Os objetivos do trabalho foram avaliar e indicar parâmetros de seleção para classificação de grãos de feijão que atendam as exigências do mercado consumidor. Foram instalados experimentos contendo 19 genótipos de feijoeiro em nove ambientes, no Estado de São Paulo. A produção de grãos foi estratificada em peneiras de classificação 10 (10/64" pol.) a 15 (15/64" pol.) e avaliada a produção relativa de grãos em peneiras 13 e 14, rendimento de peneira, massa de 1.000 grãos, tamanho de grãos e para os índices J=perfil e H=forma do grão. A produção relativa de grãos, rendimento de peneira, forma e perfil foram as características que apresentaram diferenças estatísticas significativas, indicando presença de variabilidade genética. Por meio da comparação dos resultados com testemunhas de feijoeiro já recomendadas para o setor produtivo, conclui-se que uma cultivar de feijoeiro deve apresentar alta massa de 1.000 grãos (251 a 300g), produção relativa de grãos em peneiras 13 e 14 com valores acima de sete, rendimento de peneira acima de 70,0 por cento e também sementes elípticas e perfil semiachatado.

The aim of this research was to evaluate and to direct the genetic parameters to classify the grain size of common bean, according to the market demand. Experiments with 19 common bean genotypes were assembled in nine sites in the São Paulo State. The grain yield was stratified following sieve classification 10 (10/64" inch) to 15 (15/64" inch). The following parameters were evaluated: relative yield with 13 and 14 sieves, sieve yield, thousand grain weight, grain size, J and H indexes (J=grain profile; H=grain shape). The relative grain yield, sieve yield, shapes and grain profiles presented significant statistical differences, indicating the presence of genetic variability among the genotypes. Compared to the market recommended and productive checks, the results showed that a common bean cultivar should present high thousand grain weight (251 to 300g); relative grain yield with 13 and 14 sieves should present values above seven; the sieve yield should be above 70.0 percent and it should exhibit elliptic seeds and semi-flat grain.

Estudo da estabilidade fenotípica de feijoeiro com grãos especiais / Study of the phenotypical stability of common bean plants with special grains

Obejtivou-se no presente trabalho avaliar os parâmetros de adaptabilidade e de estabilidade de linhagens e cultivares de feijoeiro, com grãos especiais, por meio do uso do genótipo suplementar (GS) em análise AMMI (Additive Main Effect and Multiplicative Interaction). Foram utilizados dados de produtividade de grãos de 14 genótipos de feijoeiro pertencentes ao ensaio de Valor de Cultivo e Uso (VCU), para o estado de São Paulo, referente às safras de 2005/2006/2007, semeados em 24 ambientes no delineamento de blocos casualizados, com três repetições. Pôde-se observar diferenças no comportamento dos genótipos em função do estímulo do ambiente, uma vez que a interação genótipo x ambiente foi significativa. Para tanto os genótipos Gen 99 TGR 34-16 (época das águas), Jalo Precoce e IAC - Centauro (época da seca), Gen 99 TG 28-68 e IAC-Centauro (época de inverno) e IAC-Boreal (conjunto das três épocas) apresentaram-se estáveis, pois seus valores de escores foram próximos de zero. Em relação ao conjunto das três épocas de semeadura não foi detectado nenhum genótipo próximo ao GS, no entanto os genótipos IAPAR-31 e IAC-Centauro (época da seca), Gen 99 TG 28-68 e IAC-Centauro (época de inverno) aproximaram-se desse ponto tendo como característica o fato de interagirem com os ambientes de maneira mais favorável possível. Sendo assim, o método AMMI combinado com o uso do GS auxilia na identificação de genótipos superiores.

The objective of the present study is to evaluate adaptability and stability parameters of lines and cultivars of common bean plants with special grains through the use of supplementary genotypes (GS) and AMMI (Additive Main Effect and Multiplicative Interaction) analysis. Productivity data of 14 lines and cultivars of common beans belonging to the Value for Cultivation and Use (VCU assay) of the State of São Paulo, referent to the harvests of 2005/2006/2007, seeded in twenty-four environments following a randomized blocks design with three repetitions, were used. It is possible to observe performance differences of the genotypes in function of environmental stimulus, since the genotype x environment integration was significant. Genotypes Gen 99 TGR 34-16 (raining period), Jalo Precoce and IAC -Centauro (dry period), Gen 99 TG 28-68 and IAC-Centauro (winter period) and IAC - Boreal (set of all the three periods) were stable, presenting score values close to zero. Regarding the set of the three seeding periods, we did not detect any genotype close to GS; nevertheless, the genotypes IAPAR-31 and IAC-Centauro (dry period), Gen99 TG 2868 and IAC-Centauro (winter period) were close to this point, interacting with environments in the most favorable way as possible. Therefore, the AMMI method combined with GS use helps to identify superior genotypes.

Avaliação da estabilidade e adaptabilidade de genótipos de feijoeiro (Phaseolus vulgaris L. ) baseada na análise multivariada da "performance" genotípica / Evaluation of the stability and adaptability of genotypes of common beans (Phaseolus vulgaris L. ) through multivariate analysis of genotype performance

Neste estudo, objetivou-se avaliar a estabilidade e a adaptabilidade de genótipos de feijoeiro, cultivados em diferentes ambientes, por meio da análise multivariada da performance genotípica, empregando-se os teores de água, o valor protéico e os parâmetros de qualidade tecnológica dos grãos (porcentagem de absorção de água antes e após o cozimento, tempo de cozimento, porcentagem de grãos inteiros, expansão volumétrica e sólidos solúveis totais no caldo), em conjunto com a produtividade média dos genótipos cultivados em diversos ambientes, visando a identificar as linhagens e/ou cultivares mais estáveis e adaptadas para o conjunto de caracteres de importância para a cadeia produtiva do feijoeiro. Para tanto, foram avaliados 19 genótipos de feijoeiro pertencentes aos ensaios de VCU (Valor de Cultivo e Uso) 2005/2006/2007 de grãos dos grupos comerciais carioca e preto para o estado de São Paulo. Os resultados obtidos pela análise multivarida para a o conjunto das três épocas de semeadura reportaram o genótipo Gen 96A98-15-3-52-1 e a cultivar IAC-Alvorada como estáveis, responsivas à melhoria dos ambientes e tolerantes nos ambientes desfavoráveis. Por meio dos resultados obtidos, conclui-se que a análise de estabilidade e adaptabilidade multivariada proposta por Carneiro (1998), baseadas em Lin & Binns (1988), mostra-se eficiente e simples para a avaliação do desempenho genotípico das cultivares, além de apresentarem unicidade do parâmetro para estimar a adaptabilidade à ambientes favoráveis e desfavoráveis, e simplicidade na interpretação dos resultados.

The purpose of this research was to evaluate the stability and adaptability of the genotypes of common beans, cultivated in different environments through multivariate analysis of genotype performance employing up water contents, protein value and technological parameters of quality (percentage of absorption of water before and after cooking, time of cooking, percentage of complete grains, volumetric expansion and soluble solid totals in the broth), together with average productivity of the genotypes. To that end, 19 genotypes of common bean of the carioca and black commercial groups, belonging the testing of VCU (Value of Cultivation and Use) of São Paulo state have been evaluated in the crops of 2005/2006/2007. According to the results obtained by multivariate analysis for the set of the three seasons of culture the genotype Gen 96A98-15-3-52-1 and IAC- Alvorada were classified as stable, responsive to improvement of the environment, and tolerant in unfavorable environments. It can be concluded from these results that the univariate and multivariate adaptability and stability analyses proposed by Carneiro (1998) based on Lin & Binns (1988) is an efficient and simple way to assess the genotype performance of the cultivars, besides presenting parameter uniqueness to estimate adaptability to favorable and unfavorable environments, with a simple interpretation of the results.

Prediction of genotypic values and estimation of genetic parameters in common bean

Eighteen common bean (Phaseolus vulgaris L.) genotypes were evaluated in 25 environments of the state of São Paulo in 2001 and 2002. The estimation of genetic parameters by the Restricted Maximum Likelihood (REML) and the prediction of genotypic values via Best Linear Unbiased Prediction (BLUP) were obtained by software Selegen-REML/BLUP. The estimate of the broad-sense heritability was low for the grain yield (0.03), since it took individual plots into consideration and was free of the effects of interaction with years, cultivation periods and site. Nevertheless, the heritability at the level of line means across the various environments was high (0.75), allowing a high accuracy (0.87) in the selection of lines for planting in the environment mean. Among the 18 genotypes, the predicted genotypic values of nine were higher than the general mean. The genetic gain predicted with the selection of the best line, in this case line Gen 96A31 of the IAC, was 16.25 percent.

Dezoito genótipos de feijoeiro (Phaseolus vulgaris L.) foram avaliados em 25 ambientes do estado de São Paulo durante os anos de 2001 e 2002. As estimativas de parâmetros genéticos por REML e a predição de valores genotípicos via BLUP foram obtidas por meio do aplicativo computacional Selegen REML/BLUP, seguindo o modelo misto para linhagens. A estimativa da herdabilidade no sentido amplo para produção de grãos foi baixa (0,03), por ser em nível de parcelas individuais e livre dos efeitos da interação com anos, épocas e locais. No entanto, a herdabilidade ao nível de médias de linhagens ao longo dos vários ambientes foi alta (0,75), permitindo alta acurácia (0,87) na seleção de linhagens para plantio no ambiente médio. Dentre os 18 genótipos, nove apresentaram valores genotípicos preditos superiores à média geral. O ganho genético predito com a seleção da melhor linhagem, no caso, a linhagem Gen 96A31 do IAC, foi de 16,25 por cento.

Identification of common bean ( Phaseolus vulgaris ) duplicates using agromorphological and molecular data

We used agromorphological and random amplified polymorphic DNA (RAPD) molecular marker data to identify duplicate common bean (Phaseolus vulgaris L. Fabaceae) accessions in the Common Bean Germplasm Bank of the Agronomical Institute - IAC (Banco de Germoplasma de feijoeiro do Instituto Agronômico de Campinas (IAC), SP, Brazil). A total of 116 accessions with the same names and similar agromorphological traits was analyzed. The divergence between the accessions was initially evaluated by means of the agromorphological descriptors using single linkage clustering, from the Euclidean distance. Multivariate analysis identified four duplicate accessions (Carioca Lustroso, Bico de Ouro, Jamapa and Preto), with 17 other same-name accessions being suspected duplicates due to their low divergence levels. Accessions with low genetic distance values (indicating that they were duplicates) were further compared using RAPD markers which confirmed the results of the multivariate analyses in relation to the four duplicate accessions, although only two of the other 17 suspect accessions were confirmed to be duplicates, in this case of accessions IAPAR 57 and Sacavem. These results show that the combined use of agromorphological and molecular information allowed a better characterization of the acessions in the common bean Germplasm Bank.