Estimativas de parâmetros genéticos e fenotípicos em famílias f2:4 de arroz de terras altas em Sinop-MT

Abstract

Aiming at the insertion of upland rice in different production systems, characteristics such as high grain yield, resistance to lodging and precocity are desirable in the new cultivars. Estimates of genetic parameters are essential for the breeding program, so that it can be conducted more assertively, as well as select the best genotypes. The present work was carried out with the objective of estimating genetic and phenotypic parameters and correlations between traits of agronomic importance of F2:4 families belonging to the Embrapa upland rice genetic improvement program. The experiment was conducted at Embrapa Agrossilvipastoril, in Sinop-MT, in the 2020/2021 harvest. A total of 169 treatments belonging to the Family Yield Assay of the Embrapa Arroz e Feijão upland rice genetic improvement program were evaluated, with 166 families and three commercial cultivars used as controls. The experimental design used was a simple 13x13 lattice. The characters evaluated were grain yield, plant height and number of days to flowering. Data for all characters were subjected to analysis of variance. For all characters there was a significant difference between the genotypes, indicating the existence of variability between them. The heritability estimates were 79.9%, 66.0% and 54.7% for the flowering, plant height and productivity traits respectively, and the correlations between the characters are mostly positive and significant, however, they are of low magnitudes. The families of the F2:4 generation of the Embrapa breeding program have great potential for the selection of superior genotypes in relation to the evaluated characters.