Caracterização genética por modelos mistos de uma população de linhas puras recombinantes de arroz irrigado

• Autor(a) principal: Garcia, Ana Letcycia Basso
• Data de Publicação: 2017
• Tipo de documento: Dissertação
• Idioma: por
• Título da fonte: Repositório Institucional da UFG
• Texto Completo: http://repositorio.bc.ufg.br/tede/handle/tede/9120
• topic: RILs; Parâmetros genéticos; Deviance; MHPRVG; Dissimilaridade; Genetic parameters; Deviance; Dissimilarity; FITOTECNIA::MELHORAMENTO VEGETAL

Improving rice yield has been a big challenge for rice breeding programs around the world. One alternative to identify inbred lines with high yield potential, and discover genes related to yield and its components is to explore the genic pool of the population originated from crosses between cultivars not regularly used, as those introduced from another country. The objective of this study was characterizing a recombinant inbred lines population from the cross between Maninjau and Epagri 108. There were evaluated 296 RILs in experiments conducted in Goianira (GO), Boa Vista (RR) and Pelotas (RS), in 2016. In the experiments in GO and RR, the alpha lattice design (17x18) with two replications were used, and in Pelotas was applied the BAF design. Data were collected for yield (PD) and plant height (AP) in the three places, days to flowering (DF), in RR and GO, 100-grain weight (PG), in RS and GO and leaf blast resistance (BS), in GO. The data were analyzed by a mixed model with the deviance analysis. Variance components were estimated by REML/BLUP and the genetic parameters and correlation coefficients were calculated. The statistics parameters as CV e , CV g , CV r and selective accuracy were also estimated. The G x E interaction analysis was processed by the MHPRVG method. Also, the genetic distances between the progenies that had highest breeding values in each place and their relatives (Maninjau and Epagri 108), was estimated, using a 24 SSR markers panel. For Boa Vista and Goianira, most of the highest yield RILs were like the parental Epagri 108. Most of the random effects of the statistic model used in this study were significant. The RILs population showed genetic variability inside (σ g2 significant). The experimental precision in RR and GO was from good to excellent with accuracy over 90% and in RS it was moderate (~50%), probably because of the environmental effect action. Yield showed moderate heritability (0,67) and the characters DF, AP and PG showed high heritability (>0,90). Positive significant correlation was observed between the characters PD and PG, and DF and AP, however the last one showed negative correlation with yield. Nine RILs had the best performance by the MHPRVG, and it was above 30% of the general mean. They are recommended for the breeding program use. The RIL 105 were ranked as the best for stability, adaptability and yield, simultaneously. These results suggest that there is a significant genetic variation between the RILs evaluated. Therefore, this population might be used either in selection of high yield performance genotypes or for QTL mapping foragronomic traits in many environments.