Badu-Apraku B, Fakorede M A B, Talabi A O, Oyekunle M, Aderounmu M, Lum A F, Ribeiro P F, Adu G B, Toyinbo J O
International Institute of Tropical Agriculture P.M.B. 5320 Ibadan Nigeria.
Department of Crop Production and Protection Obafemi Awolowo University Ile-Ife Nigeria.
Crop Sci. 2020 May-Jun;60(3):1325-1345. doi: 10.1002/csc2.20071. Epub 2020 May 5.
Vitamin A deficiency, drought, low soil nitrogen (low-N), and parasitism of maize ( L.) cause malnutrition and food insecurity in sub-Saharan Africa. The objectives of this study were to determine combining abilities of extra-early provitamin A (PVA) lines, classify them into heterotic groups (HGs), identify testers, and determine yield stability of hybrids under contrasting environments in two trials. In Trial 1, 190 F hybrids plus six checks were tested under infested, drought, and stress-free environments in Nigeria from 2015-2017. In Trial 2, 35 extra-early yellow hybrids were evaluated under low-N, -infested, and stress-free environments in 2018. TZEEIOR 202 and TZEEIOR 205 had PVA concentrations of 23.98 and 22.56 μg g. TZEEIOR 197 × TZEEIOR 205 (20.1 μg g) and TZEEIOR 202 × TZEEIOR 205 (22.7 μg g) contained about double the PVA level of the commercial check, TZEEI 58 × TZEE-Y Pop STR C5 (11.4 μg g). Both general (GCA) and specific (SCA) combining ability variances were significant for most agronomic traits, although GCA was larger than SCA effects, indicating GCA effects primarily controlled the inheritance of those traits. TZEEIOR 97 and TZEEIOR 197 were identified as inbred testers. TZEEIOR 197 × TZEEIOR 205 was identified as a single-cross tester and the most stable and highest-yielding hybrid across environments. TZEEIOR 202 and TZEEIOR 205 should be invaluable resources for breeding for high PVA. Provitamin A level was independent of hybrid yield potential, indicating that selection of superior hybrids with elevated PVA levels should be feasible.
维生素A缺乏、干旱、土壤低氮以及玉米寄生导致撒哈拉以南非洲地区出现营养不良和粮食不安全问题。本研究的目的是测定超早熟维生素A原（PVA）品系的配合力，将它们划分为杂种优势群（HG），鉴定测验种，并在两项试验的不同环境条件下测定杂交种的产量稳定性。在试验1中，2015年至2017年期间，在尼日利亚的虫害、干旱和无胁迫环境下对190个F1杂交种及6个对照进行了测试。在试验2中，2018年在低氮、虫害和无胁迫环境下对35个超早熟黄色杂交种进行了评估。TZEEIOR 202和TZEEIOR 205的PVA含量分别为23.98和22.56μg/g。TZEEIOR 197×TZEEIOR 205（20.1μg/g）和TZEEIOR 202×TZEEIOR 205（22.7μg/g）的PVA含量约为商业对照TZEEI 58×TZEE-Y Pop STR C5（11.4μg/g）的两倍。对于大多数农艺性状，一般配合力（GCA）方差和特殊配合力（SCA）方差均显著，尽管GCA效应大于SCA效应，这表明GCA效应主要控制这些性状的遗传。TZEEIOR 97和TZEEIOR 197被鉴定为自交测验种。TZEEIOR 197×TZEEIOR 205被鉴定为单交测验种，是所有环境中最稳定、产量最高的杂交种。TZEEIOR 202和TZEEIOR 205对于高PVA育种应是非常宝贵的资源。维生素A原水平与杂交种产量潜力无关，这表明选择具有较高PVA水平的优良杂交种应该是可行的。
