Genetic potential of maize populations derived from commercial hybrids for interpopulation breeding

ABSTRACT Our objective was to evaluate the genetic potential of two maize populations derived from commercial hybrids for beginning a reciprocal recurrent selection (RRS) program. For this, 280 interpopulation half-sib (HS) progenies were produced from two populations (140 HS from each population), which were derived from the selfing of the commercial hybrids AS1598 (Pop1) and RB9210 (Pop2). We then evaluated the 280 HS progenies, the two base populations, and the two hybrids for grain yield (GY) and ear and plant architecture traits in southwestern Goias during the 2020 winter season. Variance components and genetic values of each progeny were estimated using the REML/BLUP (Restricted Maximum Likelihood/Best Linear Unbiased Prediction) methodology. Genetic gains by selection of the top 20% of progenies were predicted using two strategies: i) selection for GY and ii) selection for GY and days to silking (DTS) simultaneously. We observed genetic variability in both populations for all tested traits; therefore, it is possible to obtain genetic gains from the interpopulation improvement of both Pop1 and Pop2. The genetic gain estimates with the selection based on GY were 9.03 and 3.45% for Pop1 and Pop2, respectively. Simultaneous selection for GY and DTS resulted in positive (>4%) genetic gains for GY in both populations and decreased the cycle in Pop1, but we did not observe any alteration of the cycle in Pop2. We concluded that both populations derived from commercial hybrids have genetic potential for interpopulation improvement using RRS.