Available online at www.inia.es/sjar
European flint × U.S. dent is a common heterotic pattern used in early maize (Zea mays L..) breeding programs in Europe. Two maize synthetic populations, EZS1 (formed from four Spanish flint populations), and EZS2 (formed from four American dent populations), were developed at Zaragoza, Spain. The synthetics showed heterotic behavior and were subjected to six cycles of S1 recurrent selection for increased grain yield and reduced lodging. The objective of this research was to study the effectiveness of selection on grain yield and other agronomic traits in both synthetics. The original populations, EZS1C0 and EZS2C0, and the six cycles of selection of both, were evaluated in two locations during two years. Over six selection cycles, average yield of EZS1 and EZS2 increased by 0,82 Mg ha-1 and 0.93 Mg ha-1 per cycle, respectively, and lodging decreased by 2.76% and 2.44% per cycle, respectively. Gains due to selection for all traits in both synthetics were significant. It was concluded that S1 selection was effective in improving yield and reducing lodging in each synthetic to start a reciprocal recurrent selection.
Part of this work was financed in the frame of Ministry of Education and Science of Spain project AGL2004-06776-C02-02 and for Basque Government funds.
Peer reviewed