Genetic gain in an improvement program of irrigated rice in Minas Gerais
Plínio César Soares, Patrícia Guimarães Santos Melo, Leonardo Cunha Melo, and Antônio Alves Soares
An evaluation of the genetic improvement program of irrigated rice of Minas Gerais estimated the genetic gain obtained in the 90s. Grain yield data of the advanced comparative trials of cultivars and lines of continuously flooded rice, conducted from 1990/91 to 2000/01 were used. The estimate of the genetic gain was obtained by the methodology of the adjusted means proposed by Breseghello (1998). The mean annual genetic gain in the 90s was 42.45 ± 17.89 kg ha-1 (0.7% per year). The improvement program proved auspicious for the development of lines that outmatched the controls. The mean of the cultivars released in the 90s did however not outstrip the mean of the elite lines, which were the genotypes with the highest means in this study and will be further evaluated in the ongoing program.