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The study evaluated the fodder potential of 42 promising drought-tolerant (DT) three-way cross maize (Zea mays L.) hybrids, 11 commercial hybrid checks, and 1 local variety check under irrigation. Agronomic and laboratory trials were conducted to determine their morphological traits and fodder potential. Hierarchical cluster analysis (HCA) to group cultivars into clusters is based on quantity, quality, and the combination of both variables. Selection of potential food-feed cultivars was based on the quantity traits (grain and biomass yield) and quality traits crude protein (CP), in vitro organic matter digestibility (IVOMD), and metabolizable energy (ME). Variation was found for dry matter yield (DMY) at harvest as commercial hybrid recording the maximum DMY of 14.1 t ha−1 and the highest grain yield of 1.4 t ha−1 (P < 0.01), while local check produced a minimum grain yield of 0.54 t ha−1 (P < 0.01) with grain moisture content range between 8.4 and 11.6%. The maximum mean ash content was 5.8% for DT hybrids. Average CP was the highest in commercial hybrids with a value of 6.1%. The mean values for ME were similar (P > 0.01) in both commercial hybrids (7.2 MJ/kg DM) and DT hybrid (7.2 MJ/kg DM), while the highest ME (7.6 MJ/kg DM) was recorded for the local check. Ranking of the hybrids based on grain yield, DMY, CP, ME, and IVOMD showed that cluster subgroup A3 (M1124–24, M1527-7, 30F32, and M1427-6) and A4 (M1427-3, SC637, and M1627-11) exhibited the best potential traits and can therefore be recommended for commercial cultivation following adoption trials by farmers. [ABSTRACT FROM AUTHOR]

Vitamin A Deficiency (VAD) is a major public health problem in Sub-Saharan Africa affecting 33 million preschool-age children. Enrichment of maize varieties with provitamin A could provide sustainable and affordable solution to VAD. This study was conducted to understand the extent of GEI effects on both grain yield and provitamin A content in 21 maize synthetics and identify synthetics combining stable performance with high level provitamin A content across diverse environments in West Africa. Combined analysis of variance found significant (p < 0.01) GEI effects that prompted further investigation of the GEI magnitude using mixed model with factor analysis. Factors 1 and 2 explained 71% of the total variability. G5, G4, G12, G18, G2 and G14 were broadly adapted to a range of environments and considered the most stable and high yielding. G8, G1, and G10 were specifically adapted to a group of environments. Whereas, G21, G19 and G17 were found to be the worst and unstable genotypes. G4 combined stable performance with high provitamin A content, whereas G20 and G18 were stable but had low provitamin A contents. Three genotypes, G4, G12 and G14 were found to combine stability with high provitamin A contents. These genotypes can be recommended for production in the low-land tropics of West and Central Africa with similar environments. [ABSTRACT FROM AUTHOR]

There is growing interest for yellow maize among farmers and the food and feed industries in West Africa. Testing of maize hybrids in multi-location trials is crucial for identifying adapted high-yielding candidates for quick release. This study was designed to evaluate yield stability of three-way cross yellow maize hybrids across 17 diverse environments in the savannas of West Africa. Highly significant differences (P < 0.001) were observed among hybrids across locations. The interaction between genotypes and environments was significant for grain yield and most other agronomic traits, with high repeatability (0.68) for grain yield across the test environments. The hybrid A1001-19 was found to be the highest yielding, with yield advantage of 10% over the commercial hybrid Oba Super 2. The genotype, genotype by environment biplot identified hybrid A1001-7 as the most stable hybrid with above-average grain yield, followed by A1001-10. However, A1001-19 was relatively stable and was the best hybrid in 12 of the 17 environments across Mali, Nigeria, and Sierra Leone. Kudu and Zaria 2013 were the most discriminating locations for the hybrids. The stable yield performance of A1001-7 and A1001- 10, and to a larger extent A1001-19, would benefit farmers and seed producers with limited capacity to handle single-cross hybrids. Hybrid A1001-10 was released by partners, and hybrids A1001-7 and A1001-19 have been evaluated in national performance and on-farm trials for potential release. This would provide more food for resource-poor farmers and raw materials for food and feed industries and would result in increased household incomes of smallholder farmers in West Africa. [ABSTRACT FROM AUTHOR]

Maize (Zea mays L.) is a major staple crop in West Africa and has the potential to mitigate the food insecurity in the subregion. However, maize grain yield is severely constrained by drought. A study was conducted at 13 locations in West Africa for 2 yr to determine genetic gains in yield of cultivars developed during three eras, 1988 to 2000 (first-generation cultivars), 2001 to 2006 (second-generation cultivars), and 2007 to 2010 (third-generation cultivars) under drought and optimal conditions. Under drought, yield ranged from 1346 kg ha-1 for first-generation cultivars to 1613 kg ha-1 for third-generation cultivars with a genetic gain of 1.1% yr-1. Under optimal conditions, yield gain ranged from 3363 kg ha-1 for first-generation cultivars to 3956 kg ha-1 for third-generation cultivars with genetic gain of 1.3%. The average rate of increase in yield was 14 and 40 kg ha-1 yr-1 under drought and optimum conditions. Genetic gains in yield from first- to third-generation cultivars under drought was associated with improved plant aspect and husk cover, whereas under optimum conditions it was associated with plant and ear aspects, increased ears per plant, plant and ear heights, and improved husk cover. Cultivars TZE-W DT C2 STR, DTE-W STR Syn C1, DT-W STR Synthetic, 2009 DTE-W STR Syn, and EV DT-W 2008 STR were high yielding and stable across drought environments. Substantial progress has been made in breeding for drought tolerance during the last three decades. [ABSTRACT FROM AUTHOR]

Improving maize productivity in the savannas of West Africa will depend on improving soil fertility and ensuring the efficient use of inputs and the relevant maize varieties tolerant to low nitrogen (N) that have been developed for this region. Several cycles of full-sib family selection that combine agronomic performance under low N with yield under high N to maximize gains under both environments have been used to improve three such developed populations. Evaluation of different cycles of selection revealed that desirable changes in gene frequencies had taken place after three cycles of selection in two of the three populations, leading to a yield gain of over 200 kg/ha/cycle under 30 kg N/ha and over 270 kg/ha/cycle under 90 kg N/ha. Trends in performance of the third population under low N simply indicated that additional cycles of selection would be required to shift gene frequencies significantly in the direction of increased yield production. This yield gain did not adversely affect other agronomic traits. Therefore, improving maize for tolerance to low soil N in West and Central Africa is feasible without compromising grain yield performance under high-N application. [ABSTRACT FROM PUBLISHER]

Maize (Zea mays L.) production in west and central Africa (WCA) is constrained by the parasitic weed Striga hermonthica (Del.) Benth and recurrent drought. Two early maize populations, TZE-W Pop DT STR C0 (white) and TZE-Y Pop DT STR C0 (yellow), developed from diverse genetic backgrounds, were subjected to three cycles of S1 recurrent selection under artificial Striga infestation. lnbreds and synthetic cultivars were developed from the different cycles of selection. The populations (C0), derived cultivars, and check cultivars were evaluated in 2002 and 2003 under Striga-infested and Striga-free environments in WCA. The objective was to assess the performance of the derived cultivars from the different cycles of selection. Under Striga infestation, ACR 94 TZE Comp5-Y and ACR 94 TZE Comp5-W, which were not from the selection program, were the highest-yielding group (2158 and 2124 kg ha-1, respectively). The second group comprised six products of the selection program, with grain yield ranging from 1806 to 1954 kg ha-1. The third group, with grain yield of 1498 to 1759 kg ha-1 contained mostly Striga- susceptible cultivars and the C0 of the selection program. Under Striga-free conditions, the performance of several cultivars from the selection program was equal to or better than ACR 94 TZE Comp5-Y and ACR 94 TZE Comp5-W. The genotype plus genotype x environment interaction biplot analysis demonstrated that EV DT-Y 2000 SIR C1 and TZE-W Pop DT STR C3 from the selection program, along with ACR 94 TZE Comp5-W, had stable grain yield under Striga-infested and noninfested conditions. [ABSTRACT FROM AUTHOR]

The article describes 26 maize germplasm lines which were resistant to the parasitic weed, Striga hermonthica. These inbred lines, GP-428 through GP-453 and PI 639925 through PI 639950, were developed by the International Institute of Tropical Agriculture. They also possessed resistance to southern corn leaf blight, southern corn rust and Maize streak virus. Presently at the S6 to S8 stages of inbreeding, these lines were released as Striga resistance source germplasm through regional trials in and outside of west and central Africa.