Kamweru Isaac, Beyene Yoseph, Anani Bruce, Adetimirin Victor O, Prasanna Boddupalli M, Gowda Manje
International Maize and Wheat Improvement Center, Nairobi, Kenya.
Life and Earth Sciences Institute (Including Health and Agriculture), Pan African University, Ibadan, Nigeria.
Plant Breed. 2023 Oct;142(5):607-620. doi: 10.1111/pbr.13129. Epub 2023 Jul 11.
Fall armyworm (FAW, ) emerged as a major lepidopteran pest destroying maize in sub-Saharan Africa. A diallel mating design was used to generate 210 experimental hybrids from 21 lines. Experimental hybrids and four checks were evaluated in two locations. Commercial checks suffered higher foliar and ear damage compared to the top 15 hybrids. Mean squares associated with the genotypic variation were higher than genotype-by-environment interactions for foliar and ear damage traits. Heritabilities were moderate to high. Significant correlations were observed between grain yield (GY) with ear rot (-0.54) and ear damage (-0.45). Positive and significant GCA effects were observed for GY in seven parental lines, which were developed from multiple insect resistance breeding programmes. CKSBL10153 has the highest GCA value for GY and shows significant GCA effects for foliar and ear damage traits. These lines were identified as the ideal combiners for GY and FAW resistance and are therefore recommended for utilization as testers in the development of FAW-resistant three-way cross-hybrid maize with correlated response for increased GY. GCA and marker-based prediction correlations of GY were 0.79 and 0.96, respectively. Both GCA effects and marker-based models were effective in predicting hybrid performance for FAW resistance.
草地贪夜蛾成为撒哈拉以南非洲地区破坏玉米的一种主要鳞翅目害虫。采用双列杂交设计，从21个品系中产生了210个实验杂交种。在两个地点对实验杂交种和4个对照品种进行了评估。与排名前15的杂交种相比，商业对照品种遭受的叶片和穗部损害更高。对于叶片和穗部损害性状，与基因型变异相关的均方高于基因型与环境的互作。遗传力为中度到高度。在籽粒产量（GY）与穗腐病（-0.54）和穗部损害（-0.45）之间观察到显著相关性。在7个亲本品系中观察到了对GY的正向且显著的一般配合力（GCA）效应，这些品系是通过多个抗虫育种计划培育出来的。CKSBL10153在GY方面具有最高的GCA值，并且在叶片和穗部损害性状方面表现出显著的GCA效应。这些品系被确定为GY和抗草地贪夜蛾的理想组合亲本，因此推荐将其用作测试品种，用于培育具有相关响应以提高GY的抗草地贪夜蛾三交种玉米。GY的GCA效应与基于标记的预测相关性分别为0.79和0.96。GCA效应和基于标记的模型在预测草地贪夜蛾抗性的杂交种性能方面均有效。
