Leiri Daiane Barili

Genetic gain in agronomic traits of common bean in the region of Planalto Catarinense

The purpose of this study was to predict the genetic progress in the selection for common bean agronomic traits based on the trait expression, using two indices of adaptive selection. The existence of correlation between various traits in common bean breeding is a major restriction, but some tools that allow breeders to predict the expected gains could optimize results. The following traits were evaluated: (1) plant cycle (days), (2) plant height (in cm), (3) stem diameter (cm), (4) insertion of the first pod (cm); (5) number of pods per plant; (6) number of grains per pod; (7) pod length (cm). Results show the possibility of selecting accessions for several agronomically important traits evaluated together. The only genotype selected by both indices was UDESC 03, confirming the possibility of selecting plants with superior agronomic traits among genotypes of common bean landraces.

Efeito de ambiente sobre a produtividade de feijão carioca para o Estado de Santa Catarina

Quinze genotipos de feijao (Phaseolus vulgaris L.) foram caracterizados quanto a adaptabilidade e estabilidade de rendimento de graos em cinco ambientes, para cada epoca de semeadura (safra e safrinha), em 2006 e 2007. Foram empregados os metodos de Eberhart e Russel (1966) e Wricke e Weber (1986). Os resultados indicaram a ocorrencia de forte interacao genotipo x ambiente, com reflexos em apenas quatro genotipos de feijao com baixa estabilidade de rendimento de graos quando cultivados no periodo recomendado para cultura (safra), principalmente em consequencia dos valores significativos dos desvios da regressao observados. Com base nos resultados, e possivel indicar os genotipos CHC 97-29 (safra), FAM 03 e CHC 97-15 (safrinha) para cultivo na Regiao Sul do Brasil, uma vez que houve alto rendimento de graos e insensibilidade a alteracoes de ambiente. Para cultivo na safra, FAM 03 deve ser recomendado aos agricultores altamente tecnificados, pois e responsivo significativamente as melhorias de ambiente quando cultivados na epoca recomendada para cultura.

Quantile regression for genome-wide association study of flowering time-related traits in common bean

Flowering is an important agronomic trait. Quantile regression (QR) can be used to fit models for all portions of a probability distribution. In Genome-wide association studies (GWAS), QR can estimate SNP (Single Nucleotide Polymorphism) effects on each quantile of interest. The objectives of this study were to estimate genetic parameters and to use QR to identify genomic regions for phenological traits (Days to first flower—DFF; Days for flowering—DTF; Days to end of flowering—DEF) in common bean. A total of 80 genotypes of common beans, with 3 replicates were raised at 4 locations and seasons. Plants were genotyped for 384 SNPs. Traditional single-SNP and 9 QR models, ranging from equally spaced quantiles (τ) 0.1 to 0.9, were used to associate SNPs to phenotype. Heritabilities were moderate high, ranging from 0.32 to 0.58. Genetic and phenotypic correlations were all high, averaging 0.66 and 0.98, respectively. Traditional single-SNP GWAS model was not able to find any SNP-trait association. On the other hand, when using QR methodology considering one extreme quantile (τ = 0.1) we found, respectively 1 and 7, significant SNPs associated for DFF and DTF. Significant SNPs were found on Pv01, Pv02, Pv03, Pv07, Pv10 and Pv11 chromosomes. We investigated potential candidate genes in the region around these significant SNPs. Three genes involved in the flowering pathways were identified, including Phvul.001G214500, Phvul.007G229300 and Phvul.010G142900.1 on Pv01, Pv07 and Pv10, respectively. These results indicate that GWAS-based QR was able to enhance the understanding on genetic architecture of phenological traits (DFF and DTF) in common bean.