Evaluation of Early and Late/Intermediate Maize Varieties for Grain Yield Potential and Adaptation to a Southern Guinea Savanna Agro-ecology of Nigeria

Drought-tolerant maize varieties belonging to two different maturity (10 early and 10 late/intermediate) groups were evaluated for yield and other related characters in the southern Guinea savanna (SGS) of Nigeria for two years (2009 and 2010). The differences among genotypes between and within maturity groups differed significantly (P<0.01) for grain yield, plant height, days to anthesis and silk. The effect of year x maturity group and year x maturity within group interactions was highly significant (P<0.01) only for grain yield. The rainfall patterns were favourable in both cropping years with comparable values of growth parameters. Late/intermediate maturing varieties (TZL COMP1-W C6 F2, SUWAN-1-SR-SYN, TZB-SR, OBA SUPER I, EV 8435-SR) out-yielded early maturing ones with yield advantage of 34.29% and taller by 17.04% compared to early ones. However, early varieties were early to anthesis with 6.57% advantage over late/intermediate cultivars. Four early varieties (DMR-ESR Y CIF2, AC 90 POOL 16 DT, STR, TZE-W DT STR C4 and ACR 95TZE COMP4 C3) were superior for grain yield withn a range of 4.39 to 4.68 t/ha. These genotypes could be used either as cultivar per se to escape the prolonged moisture stress during the later part of the cropping season or introgressed with favourable cultivars for high yield adaptable to drought-prone areas in the southern Guinea savanna agro-ecology.