International Institute of Tropical Agriculture, PMB 5320, Oyo Road, Ibadan 200285, Nigeria.
Council for Scientific and Industrial Research-Savanna Agricultural Research Institute (CSIR-SARI), Tamale 00233, Ghana.
Genes (Basel). 2023 Sep 30;14(10):1900. doi: 10.3390/genes14101900.
The major challenges of maize production and productivity in Sub-Saharan Africa (SSA) include infestation, recurrent drought, and low soil nitrogen (low N). This study assessed the following: (i) accelerated genetic advancements in grain yield and other measured traits of early-maturing maize hybrids, (ii) ideal test environments for selecting early-maturing multiple-stress tolerant hybrids, and (iii) high-yielding and stable hybrids across multiple-stress and non-stress environments. Fifty-four hybrids developed during three periods of genetic enhancement (2008-2010, 2011-2013, and 2014-2016) were evaluated in Nigeria, The Republic of Benin, and Ghana under multiple stressors ( infestation, managed drought, and Low N) and non-stress environments from 2017 to 2019. Under multiple-stress and non-stress environments, annual genetic gains from selection in grain yield of 84.72 kg ha (4.05%) and 61 kg ha (1.56%), respectively, were recorded. Three mega-environments were identified across 14 stress environments. Abuja was identified as an ideal test environment for selecting superior hybrids. The hybrid TZdEI 352 × TZEI 355 developed during period 3 was the most outstanding under multiple-stress and non-stress environments. On-farm testing of this hybrid is required to verify its superior performance for commercialization in SSA. Considerable progress has been made in the genetic improvement of early-maturing maize hybrids for tolerance of multiple stressors and high yield. The identified core testing sites of this study could be used to enhance the testing and selection of promising hybrids.
撒哈拉以南非洲（SSA）玉米生产和生产力面临的主要挑战包括虫害、频繁干旱和土壤氮素含量低（低氮）。本研究评估了以下内容：（i）早熟玉米杂交种在粒产量和其他测量性状方面的遗传进展速度加快，（ii）选择早熟多胁迫耐受杂交种的理想测试环境，以及（iii）在多胁迫和非胁迫环境下具有高产量和稳定性的杂交种。在 2017 年至 2019 年期间，在尼日利亚、贝宁共和国和加纳的多胁迫（虫害、管理干旱和低氮）和非胁迫环境下，评估了在三个遗传增强期（2008-2010 年、2011-2013 年和 2014-2016 年）开发的 54 个杂交种。在多胁迫和非胁迫环境下，分别从粒产量选择中获得了 84.72 公斤/公顷（4.05%）和 61 公斤/公顷（1.56%）的年度遗传增益。在 14 个胁迫环境中鉴定出三个大环境。阿布贾被确定为选择优良杂交种的理想测试环境。在第三个时期开发的杂交种 TZdEI 352×TZEI 355 在多胁迫和非胁迫环境下表现最为出色。需要在田间对该杂交种进行测试，以验证其在 SSA 商业化的优越性能。在早熟玉米杂交种对多种胁迫和高产的耐受性的遗传改良方面已经取得了相当大的进展。本研究确定的核心测试地点可以用于增强有前途的杂交种的测试和选择。
