International Institute of Tropical Agriculture (IITA) Yaoundé, Yaoundé, Cameroon.
World Vegetable Center (AVRDC), Shanhua, Tainan, Taiwan.
J Econ Entomol. 2024 Oct 14;117(5):2123-2134. doi: 10.1093/jee/toae165.
Various aphid species, including Aphis gossypii Glover (Hemiptera: Aphididae), are considered important pests of okra and other vegetables. Previous studies under 1 environment in Cameroon, Central Africa, had found multiple okra genotypes with resistance to A. gossypii. However, the stability and yield performance of the "resistant" genotypes across different environments were unknown. Ten previously identified aphid-resistant okra genotypes along with 1 commercial variety and a local landrace (specific to a given location) were compared during 2 seasons in replicated trials in 4 agro-ecological zones of Cameroon that also represent large areas of Central Africa. Aphid populations and okra yield parameters were evaluated. Breeding values were predicted using a linear mixed model for all data, and genotypes by location interactions were identified. The area under the infestation pressure curve (AUIPC) was calculated using aphid count data and subjected to resistance analysis. The Local-the most susceptible with the highest breeding value (+2.33)-and VI060794-one of the moderately resistant-genotypes had the highest yield per hectare. The only resistant genotype VI036213 had the lowest breeding value (-2.20). Genotype × location interactions were significant for yield, pod width, and plant height, while location variance was significant for all parameters evaluated. When considering that higher aphid densities could lead to greater pesticide use and, therefore higher production and environmental costs, the high-yielding VI060794-with moderate aphid resistance across multiple environments-presents an alternative or substitute for local landraces across multiple agro-ecologies of Cameroon and (by extension) Central Africa.
多种蚜虫物种，包括棉蚜（半翅目：蚜科），被认为是秋葵和其他蔬菜的重要害虫。在中非喀麦隆的一个环境中进行的先前研究发现，多种秋葵基因型对 A. gossypii 具有抗性。然而，“抗性”基因型在不同环境中的稳定性和产量表现尚不清楚。在喀麦隆的 4 个农业生态区的重复试验中，在两个季节中比较了 10 个先前确定的抗蚜虫秋葵基因型，以及 1 个商业品种和 1 个当地地方品种（特定于特定地点）。评估了蚜虫种群和秋葵产量参数。使用线性混合模型预测所有数据的育种值，并确定基因型与位置的相互作用。使用蚜虫计数数据计算侵染压力曲线下的面积（AUIPC），并进行抗性分析。局部-最敏感，最高育种值（+2.33）-和 VI060794-一种中度抗性基因型-每公顷产量最高。唯一的抗性基因型 VI036213 具有最低的育种值（-2.20）。产量、豆荚宽度和株高的基因型×位置互作显著，而所有评估参数的位置方差均显著。考虑到更高的蚜虫密度可能导致更多的农药使用，从而导致更高的生产成本和环境成本，高产量的 VI060794-在多个环境中具有中等的蚜虫抗性-为喀麦隆和（扩展）中非的多个农业生态区的地方品种提供了替代或替代方案。
