ESTIMATION OF GENETIC VARIANCES USING SELFED LINES AS PROGENITORS IN MAIZE

Abstract

Genetic variances, assuming no epistasis, are frequently estimated in maize (Zea mays L.) with North Carolina mating designs I and II. However, in obtaining the design progenies problems arise concerning the hand pollination work and the limited amount of seed per progeny. The latter is of particular importance in the evaluation of the progenies in several environments in order to consider the effect of genotype-environment interaction. In this research it is suggested the use of selfed lines of the original non-inbred population to make the genetic designs as mating units instead of the individual plants from which they were derived. This process, though would take longer to obtain the design progenies, would facilitate the hand pollination and would produce a much greater amount of seed per progeny. It is found that only with S1 lines, or with inbred families constituited with subfamilies St , it is possible to estimate the genetic variances as if with S0 plants from which they were derived.