A preliminary study for obtaining QTLs associated with yield.

BALMACEDA MARIANA; RUIZ MONICA; PAEZ S; HELGUERA, MARCELO; VANZETTI, LEONARDO; GOMEZ, DIONISIO; GONZÁLEZ FERNANDA G; BAINOTTI, CARLOS

Simposio; 1er Simposio Internacional de Mejoramiento genético vegetal; 2021

According to environment modifications as a result of climatic change, selection of genotypes that endure unfavorable conditions relays a major importance, aiming towards lowering this phenomenon’s impact over yield and quality of essential crops. Two field experiments in succesive years were performed, aiming to choose contrasting parentals in yield performance under water stress conditions, and the later selection and study of a parental population developed from parentals with this criterion. These experiments were conducted at the experimental field of EEA INTA San Juan. During the 1st year, 10 parental genotypes were tested, from which contrasting genotypes were chosen according to their water stress response. In order to choose two constrasting genotypes, we used DTI (drought tolerance index), by choosing genotypes with high DTI values, which would present better yield potential and stress tolerance. Stress treatments consisted of a reduction of the irrigation sheet to 50% of ETc (crop evapotranspiration) from stem elongation physiological maturity (ENC-MAD), while the control was irrigated throughout the cycle with 100% of the ETc in both years. By the 2nd year, same metodology was applied to 80 doubled haploid (DH) lines obtained from former contrasting parentals. During both experiments, a split-plot design was followed, where the main plot was the irrigation treatment (control, stress) and secondary plot was the genotype. Within each irrigation treatment, genotypes were randomly distributed, and four repetitions to each were done. The data obtained were analyzed through ANOVA using the Infostat software, considering in the analysis the effect of the treatments, the genotypes and the interaction between these two factors. The results in year 1 showed significant differences (p