Genetic and phenotypic parameters in the selection of upland rice genotypes

Abstract

To assist in upland rice breeding programs, estimated genetic and phenotypic parameters are extremely important in the selection of superior lines. Thus, the objective of this study was estimate the genetic and phenotypic parameters of upland rice lines of the breeding program of UFLA in partnership with Embrapa Arroz e Feijao and Epamig. The experiment was installed in an experimental area of the Department of Agriculture at UFLA. It was evaluated 36 upland rice lines of the preliminary trial of the 2014/15 season, in randomized blocks, with three replications and plots consisted of five rows and each row has four meters. For this, it was evaluated the characters: plant height (cm), yield (kg·ha-1), 100-grain weight, days until flowering, percentage of filled grains and rice blast severity. The variance analysis and genetic parameters were estimated using the software SAS. To evaluate the experimental precision was estimated the accuracy, which varied between 63% and 98%, showing experimental precision, moderate to high. The lines differed significantly for all characters, meaning there is genetic variability among genotypes evaluated. With intensity of selection of 10% of lines, it was obtained a genetic gain of 325.29 kg·ha-1 in the character productivity, a plant height (cm) reduction in 5.50 cm, and days until flowering, with a reduction of 9.23 days, with selection of earlier plants. The estimated values for heritability ranged from 38% - 96%. Estimates confirm the possible success with the selection of the upland rice lines for these characters.