Parâmetros genéticos e seleção genotípica em arroz de terras altas

Abstract

For the sustainability of upland rice and expansion of the cultivation area, it is necessary to obtain and use cultivars that are more productive and have high grain quality. For this, it is necessary to evaluate genotypes with high potential, considering the genetic parameters and the interaction genotypes x environments to identify those best suited. Within breeding programs, obtaining estimates of genetic and phenotypic parameters, genetic gains and progress over the years are essential in order to evaluate the efficiency of the program in conducting and selecting populations. In view of the above, the objective was to estimate the genotypic and phenotypic parameters in order to verify the efficiency of selection of genotypes, aiming to obtain superior cultivars in the upland rice breeding program of UFLA. The experiments of the Family Yield Trial (ERF) were conducted in the municipality of Lavras -MG, at the Federal University of Lavras, during the 2015/2016, 2016/2017 and 2017/2018 harvests. The design was randomized block design with two repetitions and plots consisting of two rows of 3.0 m. The following characteristics were evaluated: grain yield (kg.ha-1) and number of days elapsed from planting to flowering. It was verified the efficiency in the selection of progenies from Family Yield Trials of the highland rice breeding program with gains over the seasons of 187.6 kg.ha-1, for grain yield and reduction in the number of days to flowering.