Performance of tropical early-maturing maize cultivars in multiple stress environments

Maize (Zea mays L.) production in west Africa (WA) is constrained by drought, Striga hermonthica infestation and low soil nitrogen (N). Maize varieties resistant to Striga, drought, and low N are ideal for WA, but genotype × environment interaction on these traits are usually significant due to differential responses of cultivars to growing conditions. Three studies were conducted from 2007 to 2009 at five locations in Nigeria to evaluate the performance of selected early-maturing cultivars under drought stress versus well-watered, Striga-infested versus Striga-free, and in low- versus high-N environments. Drought stress reduced grain yield by 44%, Striga infestation by 65%, and low N by 40%. GGE biplot analysis showed that the genotypes TZE-W DT STR C4, Tillering Early DT, TZE-W DT STR QPM C0 and TZE-Y DT STR C4 performed relatively well in all study environments. TZE-W DT STR C4 and TZE Comp3 C1F2 were outstanding under drought, TZE-W DT STR C4, EVDT-W 99 STR QPM C0 and TZE-W DT STR QPMC0 under Striga i...