Performance prediction and stability of maize hybrids in contrasting Striga environments

Maize yield and production are significantly hampered by Striga hermonthica, causing up to 100 % yield loss under severe infestation in Africa. This research sought to: (i) assess whether extra-early maize hybrids' yield and plant aspect performance under Striga-free conditions could respectively predict yield and Striga host damage performance in Striga-infested environment; (ii) identify Striga-resistant/tolerant biofortified hybrid maize and; (iii) identify maize hybrid with stable yield and tolerance/resistance to Striga stress. To achieve the above, 150 maize hybrids (obtained from the hybridization of 30 lines using the factorial mating design II) and six checks, were examined in Striga-free and Striga-infested environments at different locations in Nigeria over two years. The regression coefficients and R² obtained when plant aspect and grain yield across Striga-free conditions were used to predict Striga host damage and grain yield across Striga infestation and vice versa were below 25 % and 4 %, respectively. These indicate that extra-early maize hybrids' response in one environment did not reliably predict the maize response in the other with respect to the traits concerned. Mean yields of the maize hybrids were 4.9 and 3.3 t/ha in Striga-free environment and under Striga infestation, respectively. Among the 150 hybrids, LINE 61 × LINE 49 exhibited the highest Striga base index value of 13.6, marking it as the most Striga-resistant/tolerant hybrid identified in the study. Genotype main effect plus genotype × environment biplot analysis identified LINE 44 × LINE 55 and LINE 61 × LINE 49 as stable and high-yielding hybrids in Striga-free and Striga-infested conditions, respectively. These hybrids are recommended for on-farm evaluation, and if found superior, should be subsequently released to maize growers in areas affected by Striga hermonthica to boost maize production and contribute to food security in Africa.