Oluwaseun Olatise, Badu-Apraku Baffour, Adebayo Moses, Abubakar Adamu Masari
Department of Crop Production and Soil Science, Ladoke Akintola University of Technology, Ogbomoso PMB 4000, Nigeria.
International Institute of Tropical Agriculture, Oyo Road, Ibadan PMB 5320, Nigeria.
Plants (Basel). 2022 Apr 1;11(7):964. doi: 10.3390/plants11070964.
Availability of maize ( L.) hybrids with elevated provitamin A (PVA) levels and tolerance to contrasting stresses would improve food self-sufficiency and combat malnutrition in sub-Saharan Africa (SSA). This study was conducted to (i) analyze selected PVA inbreds of extra-early maturity for carotenoid content, (ii) estimate the combining abilities of the inbred lines for grain yield and other agronomic traits, (iii) assign inbred lines to distinct heterotic groups (HGs), (iv) identify testers among the inbred lines, and (v) determine grain yield and stability of the PVA hybrids across contrasting environments. Thirty-three extra-early maturing inbred lines selected for high carotenoid content were crossed with four inbred testers to obtain 132 testcrosses. The testcrosses, six tester × tester crosses and two hybrid checks, were evaluated across three -infested, four drought and five optimal growing environments in Nigeria, 2014-2016. Results of the chemical analysis revealed that inbred lines TZEEIOR 109, TZEEIOR 30, TZEEIOR 41, TZEEIOR 97, TZEEIOR 42, and TZEEIOR 140 had intermediate PVA levels. Both additive and nonadditive gene actions were important in the inheritance of grain yield and other measured traits under stress and optimal environments. However, additive gene action was preponderant over the nonadditive gene action. The inbred lines were classified into three HGs across environments. Inbreds TZEEIOR 249 and TZEEIOR 30 were identified as testers for HGs I and II, respectively. The hybrid TZEEI 79 × TZEEIOR 30 was the most outstanding in terms of grain yield and was stable across environments. This hybrid should be tested extensively in on-farm trials for consistency in performance and commercialized to combat malnutrition and food insecurity in SSA.
拥有富含维生素A原（PVA）且能耐受不同胁迫的玉米（L.）杂交种，将有助于提高撒哈拉以南非洲（SSA）的粮食自给自足水平，并对抗营养不良问题。本研究旨在：（i）分析特早熟的选定PVA自交系的类胡萝卜素含量；（ii）估计自交系在籽粒产量和其他农艺性状方面的配合力；（iii）将自交系划分为不同的杂种优势群（HG）；（iv）在自交系中鉴定测验种；（v）确定PVA杂交种在不同环境下的籽粒产量和稳定性。选择了33个高类胡萝卜素含量的特早熟自交系与4个自交测验种杂交，获得132个测交组合。这些测交组合、6个测验种×测验种杂交组合以及2个杂交对照品种，于2014 - 2016年在尼日利亚的3个病虫害高发、4个干旱和5个最佳生长环境中进行了评估。化学分析结果表明，自交系TZEEIOR 109、TZEEIOR 30、TZEEIOR 41、TZEEIOR 97、TZEEIOR 42和TZEEIOR 140具有中等PVA水平。在胁迫和最佳环境下，加性和非加性基因作用在籽粒产量和其他测定性状的遗传中都很重要。然而，加性基因作用比非加性基因作用更为突出。不同环境下，自交系被分为3个杂种优势群。自交系TZEEIOR 249和TZEEIOR 30分别被鉴定为杂种优势群I和II 的测验种。杂交种TZEEI 79×TZEEIOR 30在籽粒产量方面表现最为突出，且在不同环境下都很稳定。该杂交种应在田间试验中进行广泛测试，以验证其性能的一致性，并进行商业化推广，以对抗SSA地区的营养不良和粮食不安全问题。
