Search

Choice of an appropriate donor of alleles for use in reselection programs of existing inbred lines of maize (Zea mays L.) is crucial to the success of such programs. Well-adapted local populations or exotic improved populations might be used as donors to improve a target genotype. The objectives of this study were to: (i) evaluate U.S. and Yugoslav maize populations as donors of favorable alleles for improvement of two single cross hybrids, (ii) estimate Dudley's relationship values to determine which inbred parent should be improved, and (iii) compare four estimators of the value of populations: Dudley's minimally biased estimators (Lplµ*), minimum upper bound (UBND), predicted three-way cross (PTC), and net improvement (NI). Lplµ*, UBND, PTC, and NI showed significant differences among donors for grain yield. The highest values of favorable alleles were detected in populations, which had already undergone some type of family-based recurrent selection for grain yield. The evaluation of Dudley's relationships between donors and parents of elite hybrids generally agreed with pedigree information. The improvement of both hybrids should be done with populations EP1, BS12C8, BS26, and ZPSyn1. The population EP1 can be used for comparative improvement of all three traits in the hybrid B73 x Mo17. Simultaneous improvement of grain yield and ear length in the hybrid A82/9 x L155 can be achieved with several donor populations. Rank correlations among applied estimators were positive and generally highly significant. The largest correlation values for grain yield were detected between Lplµ* and PTC., THE UTILIZATION PERIOD OF MAIZE HYBRIDS is limited and they are usually replaced with newer hybrids with better agronomic traits and properties required on the market. Reselection of inbred parents [...]