Abstract
Striga hermonthica (Del.) Benth parasitism, low soil N, and nutritional deficiencies of normal‐endosperm maize (Zea mays L.) threaten maize yield and exacerbate nutritional problems in sub‐Sahara Africa (SSA). This study was conducted (a) to evaluate genetic variation among extra‐early maturing maize hybrids with provitamin A and quality protein characteristics, (b) to investigate gene action governing the inheritance of Striga resistance, grain yield, low N tolerance, and other measured traits under low‐N, high‐N, and Striga‐infested environments, and (c) to identify hybrids with high yield and stability across environments. One hundred and fifty hybrids developed using North Carolina Design II were evaluated with six checks under low‐N, high‐N, and Striga‐infested environments in Nigeria. Mean squares for hybrids were highly significant (P < .01) for grain yield and other traits across environments. Only general combining ability (GCA) for female and/or male mean squares were significant for measured traits under low N. In addition to significant GCA effects for most traits, specific combining ability was significant (P < .05) for Striga emergence count under Striga infestation, and ear height and ears per plant under high N, indicating that additive and nonadditive genetic effects controlled the inheritance of few traits under Striga and high N, whereas additive genetic effect governed the inheritance of the traits under low N. Hybrids TZEEIORQ 55 × TZEEIORQ 26, TZEEIORQ 49 × TZEEIORQ 75, and TZEEIORQ 52 × TZEEIORQ 43 were high yielding and stable across environments and have potential for improving nutrition and maize yields in SSA.
Highlights
Maize (Zea mays L.) is an important cereal crop in West and Central Africa (WCA) as well as the dominant staple food and crop in eastern and southern Africa (Edmonds et al, 2009)
Under low N, general combining ability for male effect (GCAm) and general combining ability for female effect (GCAf) were significant for days to 50% silking (DS), days to 50% anthesis (DA), and plant height (PLHT); only GCAm was significant for ear height (EHT), whereas only GCAf was significant for anthesis–silking interval (ASI) and stay-green characteristic (STGR) (Table 2)
The GCAm and GCAf were significant for DS, SDR1, and SDR2, and GCAm alone was significant for ASI and PLHT, whereas only GCAf was significant for yield, Ears per plant (EPP), Ear aspect (EASP), and husk cover under Striga infestation (Table 3)
Summary
Maize (Zea mays L.) is an important cereal crop in West and Central Africa (WCA) as well as the dominant staple food and crop in eastern and southern Africa (Edmonds et al, 2009). A few varieties and hybrids of maize with Striga resistance and tolerance, low N tolerance, and improved provitamin A content have been developed and commercialized in WCA (Badu-Apraku et al, 2016; Menkir, Maziya-Dixon, Mengesha, Rocheford, & Alamu, 2017), no maize hybrid with Striga resistance and tolerance, tolerance to low N, extra-earliness, and high provitamin A, lysine, and tryptophan contents is available Such hybrids, if developed and commercialized, will help to jointly address Striga and low N constraints, as well as mitigate the adverse effects of vitamin A deficiency and quality protein malnutrition in WCA
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
