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Abstract 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.

ABSTRACT Water deficit can alter the morphological, agronomic, physiological, and technological traits of the common bean plant, affecting bean grain yield. In addition to yield aspects, the grain post-harvest quality is a decisive factor for the adoption of a new cultivar. Thus, this study evaluated the effect of water deficit on the physiological, morphoagronomic, and technological traits of common bean. The experiment was carried out at in a greenhouse in a randomized block design with a 30 × 2 factorial arrangement, consisting of 30 carioca common bean genotypes and two water regimes (with and without water stress), with three replications. The water deficit affected most morphological, agronomic, and physiological traits; however, it was not significant on the darkening of the seed coat. Cultivars IAC 1849 Polaco, ANFc 5, ANFc 9, BRSMG Madrepérola, IAC Carioca Aruã, TAA Dama, and Branquinho exhibited high yield potential under water stress treatment as well as slow seed coat darkening during nine months of storage. The selection of bean genotypes with slow seed coat darkening could be performed at 30 days of storage.

ABSTRACT: Common bean is a worldwide important crop. The development of varieties with durable resistance to diseases is a major challenge in common bean breeding. The present study aimed at evaluating the phenotypic and molecular selection of anthracnose resistance in a population obtained by assisted backcrossing from IAC Formoso (resistant, donor parent) × BRS Pérola (susceptible, recurrent parent). Nine microsatellites (SSRs) and one Sequence Tagged Sites (STS) markers previously linked to ANT resistance were used to genotype this progeny, and the results showed that the selection of the genotypes closest to the donor parent in the BC1F1 population decreased the number of backcrossing cycles necessary to obtain advanced isogenic lines, potentiating the use of this tool for early selection of resistant cultivars. A total of 31 % of the BC1F1 progeny was selected and backcrossed again. The progeny derived from the second backcross (BC2F3) was selected for the Carioca grain ideotype, and 42 % of the genotypes showed high resistance to anthracnose under controlled conditions of infection for races 65 and 81. Superior resistant plants were selected and evaluated under natural conditions of infection to fusarium wilt and angular leaf spot, allowing the selection of two inbred lines with higher resistance to anthracnose, fusarium wilt, angular leaf spot and postharvest quality traits such as yield, 100 seed weight, L value at seed harvest grain darkening and cooking time. The approach outlined in this paper proved to be effective to simultaneously select for disease resistance without losing technological quality aspects of the bean.

ABSTRACT: Whitefly Bemisia tabaci (Gennadius) biotype B is the major pest of common bean (Phaseolus vulgaris L.) in Brazil and other countries. Host plant resistance is one of the cornerstones of Integrated Pest Management (IPM), and assessment of cultivars for insect resistance is fundamental to provide farmers options for pest control. This study evaluated common bean resistance to whitefly in the winter and rainy seasons in Jaboticabal, Brazil, and correlated the infestation with climatic factors. The plant part and development period of common bean that are more susceptible to whitefly infestation were also examined for potential use in IPM. Field experiments were carried out using 18 and 19 commercial cultivars in the winter and rainy seasons, respectively. Whitefly eggs, nymphs, and adults in the upper part and lower part of plants were sampled from 25 to 60 days after emergence (DAE). Cultivars IAC-Una and IAC-Eldorado had less oviposition and the former also showed lower adult infestation in the winter season. In the rainy season, cultivars IAPAR-81 and Guará had a smaller number of eggs, whereas IAC-Centauro was less infested by nymphs. The number of nymphs and adults was similar among cultivars in the winter and rainy seasons, respectively. The upper part of plants had a greater number of eggs and adults, while, the lower part harbored larger numbers of nymphs. Common bean was more susceptible to whitefly at 25-32 DAE in both seasons. These results add useful information to IPM of whitefly 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.

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.

The aim of this study was to evaluate the resistance of 58 common bean lines against common bacterial blight (Xanthomonas axonopodis pv. phaseoli) and bacterial wilt (Curtobacterium flaccumfaciens pv. flaccumfaciens). The experimental design consisted of completely randomized blocks, with four replications per pathogen. The results were subjected to variance analysis by the F test at 1% probability. Significant differences between the treatments indicated different resistance levels among the lines against both pathogens. According to the Scott-Knott test, six lines were resistant to Xanthomonas axonopodis pv. phaseoli, 14 moderately resistant, and 38 susceptible. To Curtobacterium flaccumfaciens pv. flaccumfaciens, 11 lines were resistant, 26 moderately resistant and 21 susceptible. Among these, the lines Pr10-3-4/1, Pr10-5-2/1 and Pr10-5- 2/2 of the black bean group and C10-2-4/2 of the Carioca group were resistant to both major bacterial diseases affecting common bean in Brazil.

Common bean is a highly important food in tropical regions, where most production occurs on small farms with limited use of technology and, consequently, greater vulnerability to abiotic stresses such as nutritional stress. Usually phosphorus (P) is the most limiting nutrient for crop growth in these regions. The aim of this study was to characterize the gene expression profiles of the genotypes of common bean IAC Imperador (P-responsive) and DOR 364 (P-unresponsive) under different P concentrations using RNA-seq transcriptome sequencing technology. Plants were grown hydroponically, with application of two P concentrations (4.00 mg L-1 restrictive level and 8.00 mg L-1 control level). Differential expression analyses, annotation, and functional classification were performed comparing genotypes within each P rate administered and comparing each genotype response to the different P levels. Considering differential expression analyses within genotypes, IAC Imperador exhibited 1538 up-regulated genes under P restriction and 1679 up-regulated genes in the control, while DOR 364 exhibited 13 up-regulated genes in the control and only 2 up-regulated genes under P restriction, strongly corroborating P-unresponsiveness of this genotype. Genes related to phosphorus restriction were identified among the differentially expressed genes, including transcription factors such as WRKY, ERF, and MYB families, phosphatase related genes such as pyrophosphatase, acid phosphatase, and purple acid phosphatase, and phosphate transporters. The enrichment test for the P restriction treatment showed 123 enriched gene ontologies (GO) for IAC Imperador, while DOR 364 enriched only 24. Also, the enriched GO correlated with P metabolism, compound metabolic processes containing phosphate, nucleoside phosphate binding, phosphorylation, and also response to stresses. Thus, this study proved to be informative to phosphorus limitation in common bean showing global changes at transcript level.

Resumo:O objetivo deste trabalho foi avaliar a resistência de genótipos de feijoeiro aos principais patógenos da cultura, bem como a adaptabilidade e a estabilidade de produção de grãos desses genótipos. Avaliaram-se 26 genótipos de feijoeiro quanto à resistência a Colletotrichum lindemuthianum, Fusarium oxysporum f. sp. phaseolie Xanthomonas axonopodis pv. phaseoli, por meio de inoculação, em laboratório, e em 19 ensaios de valor de cultivo e uso (VCU), em diferentes locais do Estado de São Paulo, nas safras das "águas", "seca" e "inverno", durante os anos agrícolas 2011, 2012 e 2013. Dezoito genótipos foram considerados resistentes: sete deles a C. lindemuthianum, sete a F. oxysporumf. sp. phaseolie quatro a X. axonopodispv. phaseoli. A reação de resistência aos patógenos está associada à estabilidade dos genótipos. Por meio das análises GGE biplot, foi possível identificar genótipos com adaptabilidade e estabilidade superiores às das testemunhas, nos dois grupos de tegumento avaliados, em todas as épocas de semeadura.

Bacterial wilt is one of the main diseases of common beans and the use of cultivars with some level of resistance is fundamental for an adequate disease management. The reaction of 54 common bean genotypes to Curtobacterium flaccumfaciens pv. flaccumfaciens (Cff) was evaluated, and the colonization of cultivars and obstruction of primary xylem vessels at the petiole base were assessed. In greenhouse and laboratory tests, resistance was detected in the cultivars IAC Diplomata, IAC Alvorada, IAC Imperador, IPR Corujinha, and IPR Tangará, and in the lines P5-4-4-1 and C4-5-4-1-2. The Cff colonization rate was also slower in the resistant cultivars (IAC Diplomata, IAC Carioca Tybatã, and IAC Carioca Pyatã) and the percentage of obstruction of primary xylem vessels at the petiole base lower than in the susceptible cultivars (IAC Carioca and Pérola).

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.

Value for Cultivation and Use (VCU) trials are undertaken when evaluating improved common bean (Phaseolus vulgaris L.) lines, and knowledge of agronomic and market-related traits and disease reaction is instrumental in making cultivar recommendations. This study evaluates the yield, cooking time, grain color and reaction to anthracnose (Colletotrichum lindemuthianum), Fusarium wilt (Fusarium oxysporum f. sp. phaseoli) and Curtobacterium wilt (Curtobacterium flaccumfaciens pv. flaccumfaciens) of 25 common bean genotypes derived from the main common bean breeding programs in Brazil. Seventeen VCU trials were carried out in the rainy season, dry season and winter season from 2009 to 2011 in the state of São Paulo. Analyses of grain color and cooking time were initiated 60 days after harvest, and disease reaction analyses were performed in the laboratory under controlled conditions. In terms of yield, no genotype superior to the controls was observed for any of the seasons under consideration. Grains from the dry season exhibited better color, while the rainy season led to the shortest cooking times. The following genotypes BRS Esteio, BRS Esplendor and IAC Imperador were resistant to anthracnose, Fusarium wilt and Curtobacterium wilt and, in general, genotypes with lighter-colored grains were more susceptible to anthracnose and Fusarium wilt.

The Instituto Agronômico de Campinas – IAC registered the carioca type common bean cultivar IAC Milênio. The cultivar has a mean yield of 2831 kg ha-1, high grain quality with tolerance to darkening, and resistance to Fusarium oxysporum and physiological races 81, 89, and 95 of the anthracnose pathogen (Colletotrichum lindemuthianum).

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.

Common bean (Phaseolus vulgaris L.) is frequently grown in weathered soils with low phosphorus (P) availability, and this is one of the main limitations on its production. This study aimed to assess 20 common bean genotypes in a hydroponic system to select the best P concentration for inducing nutritional deficiency and to classify the genotypes in terms of nutrient utilization efficiency. The concentrations of P applied were 8.00, 4.00, 2.00 and 0.05 mg L¹. At 21 days, in the plot subjected to an application of the most severe stress, the 0.05 mg L¹ dose of P, had smaller plant size and early leaf abscission was observed. The 4.00 mg L¹ dose of P was the most efficient in inducing stress for discrimination of cultivars in terms of efficiency of use of P. The following genotypes: IAPAR 81, Carioca Comum, IAC Carioca Tybatã, IAC Imperador and G 2333 stood out as being efficient and responsive to P, while the two cultivars DOR 364 and Jalo Precoce were the most inefficient and unresponsive.

O objetivo deste trabalho foi identificar genótipos, superiores em produtividade, adaptabilidade e estabilidade, na produção de grãos de feijoeiro, por meio da análise Lin & Binns (1988), modificada por Carneiro (1998). Foram avaliados vinte e dois genótipos pertencentes aos principais programas de melhoramento do país. Essas avaliações constaram de dados dos ensaios de VCU 2007/2008/2009 para o Estado de São Paulo, que seguiram as normas estabelecidas pelo MAPA/SNPC, para ensaios de campo. Estes ensaios foram instalados em vinte e quatro ambientes, nas épocas das águas de 2007 e 2008, seca de 2008 e 2009 e inverno de 2008 e 2009. Os resultados obtidos no conjunto dos anos e ambientes de 2007/2008/2009 demonstraram que os genótipos 'Gen C2-1-3', 'CNFC 10408', 'Juriti Claro' e 'LP 04-72' comportaram-se como os mais estáveis e adaptados. O método Lin & Binns (1988), modificado por Carneiro (1998), mostrou-se adequado para análise dos dados, identificando os genótipos mais estáveis, produtivos e adaptados aos ambientes de cultivo.

The Instituto Agronômico (IAC) is a public institution that was founded in 1887 and has the mission of generating science and transferring technologies for the agricultural sector. This paper describes the main achievements in plant breeding and the use of IAC’s cultivars. The impact in the agribusiness sector is demonstrated by the release of research results, especially in the form of products such as seeds and seedlings of 90 species. Out of these, 955 cultivars were properly described, characterized and made available to farmers (636 of them are registered in the National Cultivar Registration Service). Between 1932 and 2012, IAC released an average of 12 cultivars per year, and in the period of 2003 to 2012, 185 cultivars were registered (one new cultivar every 20 days). The results can be evaluated by the representativeness of IAC in the use, customs and food preferences, among other possible measurements on the economic impact and/or return on investments made in the Institution.

The development of new cultivars is the ultimate goal of breeding programs and is the result of many years of hard work and dedication of breeders and their teams. An important part of the process, often neglected by geneticists, is the stage from recommendation to the production of breeder seed (post-breeding). This paper discusses the role of the breeder in the recommendation, registration, protection and marketing of new cultivars. The breeder’s active participation in all phases of post-breeding is fundamental to ensure that the cultivar reaches farmers quickly and can provide the benefits expected by society

Anthracnose caused by the fungus Colletotrichum lindemuthianum is one of the main diseases affecting the common bean (Phaseolus vulgaris L.), and the pathogen is characterized by wide variability, with more than 50 physiological races identified in Brazil. Greater occurrences of races 65, 73, and 81 have been observed in Brazil along with the occurrence of pathogenic variability among isolates of a single race, destabilizing the resistance of commercial cultivars. Therefore, the aim of this study was to identify physiological races of C. lindemuthianum isolates collected in the states of São Paulo and Santa Catarina, Brazil and to test for variability among the isolates of race 65. The classification of 51 isolates resulted in the identification of 10 different physiological races: 4, 38, 55, 65, 73, 81, 83, 85, 321, and 351. Races 65 and 81 predominated, with frequencies of 37.25 and 35.29%, respectively. Regarding the isolates of race 65, wide physiological variability was evident, suggesting that a new differential set should be applied to detect the levels of variation among isolates of a single race of the pathogen.

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.

In the state of São Paulo, common bean is an important crop and the Agronomic Institute (Instituto Agronômico – IAC) registered the “carioca” (beige with brown stripes) bean cultivar IAC Imperador in the MAPA/RNC, exhibiting mean yield of 2,266 kg/ha in the 17 environments evaluated, a 75-day cycle, resistance to soil diseases and high quality seeds

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% 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% and it should exhibit elliptic seeds and semi-flat grain.

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.

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.

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%.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%.

Common bean types with pinkish and light brown teguments were predominant in Brazil before 1970, until therelease of the Carioca common bean. To avoid that these common bean types sink into oblivion, the Instituto AgronômicoCampinas applied for the registration of two cultivars by the MAPA/RNC: IAC-Galante (pinkish) and IAC-Centauro (lightbrown), with high yield and resistance to anthracnose and common mosaic.

Common bean types with special grains are considered an alternative for certain domestic and export markets.IAC-Boreal and IAC-Harmonia were developed by the Instituto Agronômico Campinas and offer an excellent type of commercialgrains, upright plant growth, earliness and high yield to supply these markets.

The aim of common bean breeding programs is the development of high-yielding cultivars, with multipledisease resistance and high technological and nutritional grain quality. Two cultivars, IAC-Alvorada with carioca grain, andIAC-Diplomata with black grain, meet these standards, according to the results of trials of Value for Cultivation and Use(VCU) 2005/2006/2007 in São Paulo. The cultivars, developed by the Instituto Agronômico de Campinas, were registered bythe MAPA/RNC.

Germplasm banks store genotype samples, improved varieties, landraces and wild species, all generically denominated accessions. The importance of characterizing germplasm banks is based on the identification and knowledge of relevant traits for genetic improvement and ex situ germplasm conservation. Thus, the present study had as aim the evaluation of the genetic diversity among 220 accessions of a Brazilian common bean germplasm bank of the "Instituto Agronômico de Campinas" (IAC) by means of 23 morpho-agronomical descriptors and 19 RAPD loci. These accessions correspond to genotypes from the Andean and Middle American gene pool as well as from cultivars derived from common bean improvement programs. The Middle American accessions and the improved cultivars were clustered into one group, distinct from the one formed by the Andean accessions. In relation to the molecular data, 47% of the genetic similarity was detected among the Middle American accessions, and similar results were observed for the improved cultivars (50%). The Andean accessions revealed 60% of genetic similarity. The cluster constituted by the improved cultivars and the Middle American genotypes differed, basically, in tegument color. Both molecular and morpho-agronomical data sets were equally effective to quantify and organize the genetic diversity of common bean accessions. This information may be useful to direct crosses and for the proper organization of the IAC germplasm bank.Bancos de germoplasma guardam amostras de genótipos, variedades melhoradas, crioulas e espécies selvagens, todas genericamente denominadas acessos. A importância da caracterização de bancos de germoplasma reside na identificação e no conhecimento de características relevantes para o melhoramento genético e para conservação ex situ do germoplasma. Avaliou-se a diversidade genética entre 220 acessos de feijoeiro de um banco brasileiro de germoplasma de feijoeiro localizado no IAC (Instituto Agronômico, Campinas), por meio de 23 descritores morfo-agronômicos e 19 locos de RAPD. Os acessos correspondem a genótipos do pool gênico andino e mesoamericano e também por cultivares resultantes de programas de melhoramento de feijoeiro. Os acessos mesoamericanos e as cultivares melhoradas foram agrupados em um mesmo grupo, distintamente dos acessos andinos. Com base nos dados moleculares, 47% de similaridade genética foi detectada entre acessos mesoamericanos e resultados semelhantes foram observados para as cultivares melhoradas (50%). Os andinos apresentaram 60% de similaridade genética. O cluster formado pelas cultivares melhoradas e genótipos mesoamericanos apresentou diferenças quanto à coloração do tegumento. Ambos os conjuntos de dados, moleculares e morfo-agronômicos, foram igualmente eficientes para quantificação e estruturação da diversidade genética de acessos de feijoeiro. Essas informações poderão ser utilizadas para orientação de cruzamentos e para a conservação adequada do banco de germoplasma de feijoeiro do IAC.

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.

Com o objetivo de conhecer o comportamento de linhagens de feijoeiro nas três épocas tradicionais de plantio do Estado de São Paulo, com base em dados de estabilidade fenotípica, dois grupos de experimentos foram instalados nas épocas das águas (setembro-outubro), da seca (janeiro-fevereiro) e de inverno (maio-junho). O grupo 1 (G1), com 47 experimentos, foi formado por 16 linhagens e o controle, cultivar Carioca 80SH, e o grupo 2 (G2), com 44 experimentos, formado por 11 linhagens e pelos controles, cultivares Carioca 80SH e Rosinha G2. O delineamento experimental foi o de blocos ao acaso, com cinco repetições e parcelas constituídas de uma linha de 5 m de comprimento. As análises de variância das produções de grãos foram realizadas por experimento dentro de cada grupo (G1/G2) e conjunta (geral e por época de plantio). Os parâmetros de estabilidade foram estimados pelo método proposto por Cruz et al. (1989). Foram observadas várias linhagens adaptadas em ambientes desfavoráveis em pelo menos uma época de plantio. Diversos genótipos comportaram-se como responsivos ou estáveis nos dois conjuntos de experimentos. Os resultados sugerem a possibilidade de direcionar a recomendação de cultivares, com a escolha das linhagens mais adaptadas e responsivas, específicas para as épocas de cultivo.

In Brazil, the trade of common beans with specialty grains such as Jalo, Bolinha, Jabola, Vermelho, Rajado,Branco, Pintado and Canário is still considered a niche market when compared to the carioca and black grain types.However, the cultivation of these beans has proved promising as an alternative income source for farmers, since it offers adifferentiated and more valuable product. IAC-Jabola and IAC-Esperança were developed by the Instituto AgronômicoCampinas (IAC) in view of their excellent grain type, plant size and higher mean yield than the standard control Jalo Precoce.The IAC had these cultivars registered in MAPA/RNC based on results of 24 VCU trials in 2005/2006/2007, in the state of SãoPaulo. The yield of IAC Jabola was 2124 kg ha-1, 2336 kg ha-1, and 2558 kg ha-1, in the rainy, dry and winter seasons,respectively. The IAC- Esperança produced 1718 kg ha-1, 1545 kg ha-1, and 2263 kg ha-1 in the rainy, dry and winter seasons,respectively.

O comportamento de quatro cultivares de feijoeiro-comum, Phaseolus vulgaris (Leguminosae-Faboideae), foi avaliado em diferentes espaçamentos. Utilizou-se o delineamento de blocos casualizados em parcelas subdivididas com quatro repetições, em que as parcelas eram representadas pelos espaçamentos de 30, 40 e 50 cm entre linhas com 10 plantas por metro e as subparcelas pelos cultivares IAC-Carioca Pyatã, IAC-Maravilha, Carioca e Pérola, avaliando-se os caracteres: número de dias para o florescimento (NDF), altura da planta no florescimento (APF), número de dias para a maturação (NDM), altura da planta na maturação (APM), fechamento entre linhas (FECH) e PG (kg/ha). Os resultados obtidos mostraram efeitos significativos para cultivares para todos os caracteres em estudo e efeito significativo de espaçamento (P < 0,05) somente para FECH. Não houve efeito significativo na interação. O FECH mostrou efeito significativo de regressão linear (R2=0,89) com espaçamentos. O cultivar IAC-Maravilha apresentou a maior média para NDF (57,08 dias), NDM (105,58 dias), APM (57,33 cm) e FECH (71,5 dias), não diferindo dos cultivares Pérola e Carioca para APF. Para PG, somente IAC-Maravilha diferiu dos demais apresentando a menor média de rendimento de grãos. Correlações significativas foram encontradas entre NDF e FECH (r = 0,95); NDF e NDM (r = 0,95); FECH e NDM (r = 0,99); NDM e APM (r = 0,95) e entre APM e PG (r = -0,98). A diminuição dos espaçamentos entre linhas propicia um aumento no rendimento de grãos. Entretanto, cultivares que apresentam maior altura e ciclos mais tardios exigem um período mais demorado para o fechamento do dossel, resultando, assim, em uma menor produtividade de grãos

ABSTRACT Given the impact of climate issues and their direct influence on agricultural production, the aim of this study was to identify superior genotypes of dry edible common bean under water deficit. Thus, 30 common bean genotypes were evaluated under controlled greenhouse conditions in a randomized block experimental design with split plots and four replications; the plots consisted of the water treatments (irrigated and water deficit) and the split plots consisted of the genotypes. The results showed genetic variability among the accessions evaluated, and in spite of significant reduction in grain yield and stomatal conductance under water deficit, these two traits showed significant, positive correlation and are able to be applied in early selection of genotypes under this stress condition. Another important response was in relation to the genotypes SER-16, SEN 92, FT Paulistinha, Carioca Precoce, IAC Imperador, and SXB 410, which showed the best yield performances in the two water treatments applied. They can be widely used in breeding programs for development of new cultivars, especially aiming at drought tolerance.

ABSTRACT: The aim of this study was to investigate the effect of heat stress on 12 bean genotypes through the analysis of their reproductive biology in terms of flowering, pollen viability, meiotic behavior, and production. Plants were grown in a climate chamber at 25-20 °C (day and night) and at a high temperature treatment 37-26 °C (day and night) from the vegetative (V4) development stage to physiological maturity. The experimental design was 2 × 12 factorial arrangement with six replications and the factors consisted of heat treatments and genotypes. In three replications, the number of newly opened flowers was checked daily. At physiological maturity, the following traits were evaluated: percentage of pod set, number of pods, number of viable seeds, number of aborted seeds, 100 seed weight, and seed yield (g per plant). The other three replications were used to collect flowers to create slides to study viability of the pollen grain and analyze the meiotic behavior. The heat treatment factor significantly affected the following traits: total number of pollen grains, number of flowers, number of pods, pod set, number of viable seeds, 100 seed weight, and seed yield. The raised temperature reduced these variables, except for percentage of pod set, and increased meiotic irregularities. The mean values regarding seed yield were 16.39 g per plant for the control treatment and 7.46 g per plant under high temperature. IAC Imperador, FT Nobre, Pérola, BRS Estilo, and IAC Diplomata stood out for higher bean seed yield under increased temperature.

ABSTRACT The slow darkening of grains is sought by bean breeders because the consumers consider that darker grains demand more time for cooking. The analysis currently used takes around 90 days to differentiate grain color among genotypes. The objective was to evaluate the color as a function of the value of L* (lightness) of carioca beans, by natural and accelerated methods to verify equivalence between methods, validation of the methodology and identification of genotypes tolerant to the darkening. The grain darkening was compared and evaluated by natural darkening method under shelf conditions, in days storage, and accelerated darkening method under ultraviolet light, in hours. The natural darkening time of 90 days was statistically equal to 24 hours of accelerated darkening, and the difference among the genotypes could be obtained in a shorter time, indicating a correspondence in the methods. The accelerated darkening method can be used to shorten the analysis time in the routine of breeding programs.