Genetic Parameters and Predictive Genetic Gain in Maize with Modified Recurrent Selection Method

Abstract

The modified recurrent selection method suggests a less productive population to test the other population more productive and itself aiming to have more genetic gains than tradition recurrent selection method that uses one population to test the other one. The objectives of this work were to estimate the genetic components, to predict and to evaluate the genetic gains of the SynFlint and Syndent populations of maize (Zea mays L.), applying a modified recurrent selection method. Two recombination cycles were carried out, with 144 S1 progeny per cycle. These progenies were test crossed with SynFlint, generating a SynFlint × Syndent inter-population and a SynFlint × SynFlint intra-population. The progenies were evaluated in five environments in the first cycle of selection and in three in the second cycle of selection, in a 12 × 12 lattice. Genetic variability in plant height and ear height, ear weight and prolificacy was observed in the first cycle of selection and in plant height and ear height in the second cycle. The intensity of selection practiced in the first cycle exhausted the genetic variability in ear weight and prolificacy. It can conclude that the two maize populations evaluated do not show adequate levels of genetic variability and predicted genetics gains estimates to allow their use in breeding programs to obtain lines and superior hybrids; and the modified recurrent selection method is inefficient to increase in population performance per se for the two populations.

Estimación de parámetros genéticos y selección de líneas S1 en una población segregante de maíz tropical

“…Since there is no significant difference between this value and from the original population, changes is not expected in days to flowering in the population from cycle one. Finally, the expected genetic gain for plant height in selected segregating lines is 17.46 cm, a similar trend for the same trait in genetic gain (11.65 cm) in a intrapopulation selection cycle based on half sibs families in maize (Afonso et al, 2012).…”

“…Dado que no es significativa la diferencia de este valor y el de la población original, no se esperaría cambio en los días a floración en la población ciclo uno. Finalmente, la ganancia genética esperada para la altura de planta en las líneas segregantes selectas es de 17.46 cm, tendencia similar resultó para el mismo carácter en la ganancia genética (11.65 cm) en un ciclo de selección intrapoblacional basado en familias medios hermanos en maíz (Afonso et al, 2012).…”