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Mid parent and coefficient of parentage as predictors for screening among single crosses for their inbreeding potential

José Francisco Ferraz de Toledo

Centro Nacional de Pesquisa de Soja - EMBRAPA, Caixa Postal 1061, 86001 Londrina, PR

ABSTRACT

A method that allows the early comparison of the proportions of the distributions of inbred lines derivable from single crosses scoring above or below given standards is presented. The method uses information usually already available to the breeder. The mean and genetic variability of the random inbreds are estimated from the mid parental values and the inverse of the Malècot's parentage coefficient, respectively. The mid parental values are available from the line or cultivar testing experiments and the Malècot's coefficients an easily calculated from the ancestry of the parents. The method was efficient for selecting superior crosses.

Keywords: Mid parent; Inbreeding potential.

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