Effects of plot size on the estimation of genetic parameters in sugarcane families

Abstract

An optimization of the use of resources in sugarcane breeding programs that would not interfere with the genetic evaluations is desirable and of great importance. The costs could be reduced and the chances of success would be higher through the possibility of investing rationally in a larger number of available genetic resources. Our study evaluated the smallest number of rows per plots of sugarcane families for yield traits; the variations in the parameter estimates for different plot sizes were discussed; and the ideal plot size was estimated by the maximum curvature method. Plot reduction leads to gradual CV increases and interferes with the ratio CVg/CVe, which in some cases dropped to values below one unit, indicating experimental inaccuracy. Heritability estimates decrease with plot size. The maximum curvature method showed that 2-row plots are enough to evaluate all characteristics.