INFLUENCE OF POPULATION SIZE ON ESTIMATES OF GENETIC VARIANCES, HERITABILITY AND PREDICTED GAINS IN TWO TROPICAL MAIZE POPULATIONS

• Q.O. Oloyede-Kamiyo

  Institute of Agricultural Research and Training (IAR&T), Obafemi Awolowo University, P.M.B.5029, Moor Plantation, Apata, Ibadan, Nigeria.

  Author

The cost of evaluating large sample size is a limitation in population improvement programme. A study was conducted in Ibadan and Ikenneto assess the influence of population size on estimates of genetic variability and predicted gains in two maize populations. Four population sizes tagged P-250, P-200, P-150 and P-100 were generated from each of the two maize populations using NCII mating scheme. The experiment was laid out in a randomized incomplete block design in two replications. Data were collected on agronomic and yield traits. Genetic parameters and narrow-sense heritability were estimated from combined analysis of variance. The type of gene action controlling each trait is consistent in all the population sizes although values were higher in other population size compared to P-250 for most of the traits studied. Means, heritability estimates and predicted gains were higher in P-200 and P-150 compared to P-250 especially for yield and yield traits. Estimates of heritability and gains were also high in P-100 but this was not consistent especially for yield traits. Considering the cost of evaluating large number of samples in population improvement programme, sample size of only 150 could be used without compromisingvariability and genetic progress.

1. Q.O. Oloyede-Kamiyo, Institute of Agricultural Research and Training (IAR&T), Obafemi Awolowo University, P.M.B.5029, Moor Plantation, Apata, Ibadan, Nigeria.

   Institute of Agricultural Research and Training (IAR&T), Obafemi Awolowo University, P.M.B.5029, Moor Plantation, Apata, Ibadan, Nigeria.

• PDF