Maize (Zea mays L.) is a key component of the daily diet in Angola, but its grain yield remains low at about 1 t ha-1 due to several factors including the use of low-yielding local varieties. The purpose of this study was to evaluate the grain yield of two hybrid maize varieties grown in Sumbe, Cuanza Sul province to increase current yield levels. The study was laid in a randomized split-plot block design with three replications over three growing seasons 2018-2021 using crop variety (ZM521-y vs. GV664-A) as the main treatment and N-fertilization (control vs. 150 kg ha-1) as sub-treatment. Sowing dates were March 26, April 16, and March 10 in 2018, 2020, and 2021, respectively, using 80cm?40cm row spacing. The overall yield was 3.6 t ha-1 across all treatments with significant effects of crop variety (p = 0.012) and growing seasons (p < 0.001) despite the non-significant effect of N-fertilization. Significant growing season?crop variety interactions showed that a maximum yield of 6.9 t ha-1 was obtained from the ZM521-y variety in 2020. Therefore, there is clear potential to increase yield levels of maize grown in Sumbe municipality, particularly if the ZM521-y variety is used with supplementary irrigation.

Keywords: Maize, productivity, Sumbe, grain yield