Badu-Apraku, B.Talabi, A.O.Ifie, B.E.Chabi, Y.C.Obeng-Antwi, K.Haruna, A.Asiedu, R.2019-06-202019-06-202018-07DOI: 10.2135/cropsci2018.03.0168http://ugspace.ug.edu.gh/handle/123456789/3099212 Drought is a key maize (Zea mays L.) production constraint in sub-Saharan Africa (SSA). Fourteen, 13 15 and 25 extra-early maturing maize cultivars, with varying Striga resistance, drought and low soil 14 nitrogen tolerance, were developed from 1995 to 2000 (Period 1), 2001 to 2006 (Period 2) and 2007 to 15 2012 (Period 3), respectively. The objectives of this study were to examine yield gains in the cultivars, 16 investigate inter-trait relationships and yield stability under six drought and 17 rain-fed conditions in 17 West Africa, 2013-2016. Annual rate of yield increase across cultivars was 0.034 Mg ha-1 (3.28 %) 18 and 0.068 Mg ha-1 (2.25 %) while yield gains per period were 0.17 and 0.38 Mg ha-1 under drought and 19 rain-fed environments, respectively. Yield gains under drought and rain-fed environments were related 20 to prolonged flowering period, increased plant and ear heights, improved stalk lodging, ear and plant 21 aspects, whereas delayed leaf senescence and increased number of ears per plant (EPP) accompanied 22 yield improvement under drought only. Ear aspect and EPP were primary contributors to yield and 23 could be used as selection criteria for yield enhancement under drought and rain-fed conditions. High 24 yielding and stable cultivars across all environments based on additive main effects and multiplicative 25enArticle