Monitoring genetic gain is crucial to ensure breeding programs' effectiveness and identify potential challenges and areas for their improvement. Our study provides a first overview of the trends in genetic gain for tuber yield and disease resistance traits in the IITA's (International Institute of Tropical Agriculture) yam breeding program. We used historical data (2010–2022) from multiple generations of past breeding cycles evaluated at 31 sites in the white Guinea yam (Dioscorea rotundata Poir) breeding pipeline and 28 sites in the water yam (Dioscorea alata L.) breeding pipeline of IITA and its national partners in West Africa. Our result shows positive genetic trends in fresh tuber yield while recording a gain of 1.38% or 99.17 kg ha⁻¹ per year in the white Guinea yam and 2.18% or 252.41 kg ha⁻¹ per year in the water yam breeding pipelines. Genetic trends for virus and anthracnose resistance were in the desired direction but negligible in white Guinea yam, while significant for virus and nonsignificant for anthracnose resistance in water yam. Our findings indicate that while the breeding program has succeeded in enhancing tuber yield, post-harvest tuber dry matter content and disease resistance (yam mosaic virus and anthracnose) did not follow a similar trend in the material being developed. This implies that the yam breeding program needs to strike a balance between various traits, ensuring that increased yield does not come at a cost to food quality or disease resistance. Our results highlight the importance of continually monitoring and assessing the performance of a breeding program and making informed decisions about which traits to focus on for future improvement.

中文翻译：

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IITA 育种计划中山药遗传增益的趋势


监测遗传增益对于确保育种计划的有效性并确定潜在挑战和需要改进的领域至关重要。我们的研究首次概述了 IITA（国际热带农业研究所）山药育种计划中块茎产量和抗病性状的遗传增益趋势。我们使用了过去多代育种周期的历史数据（2010-2022），对 IITA 的白几内亚山药 (Dioscorea rotundata Poir) 育种管道中的 31 个地点和水山药 (Dioscorea alata L.) 育种管道中的 28 个地点进行了评估。其在西非的国家合作伙伴。我们的结果显示了新鲜块茎产量的积极遗传趋势，同时白几内亚山药每年增产 1.38% 或 99.17 公斤公顷 ⁻¹ ，每年增产 2.18% 或 252.41 公斤公顷 ⁻¹ 当年在水山药养殖管道中。白几内亚山药的病毒和炭疽病抗性的遗传趋势符合预期方向，但可以忽略不计，而水山药的病毒和炭疽病抗性遗传趋势显着，但不显着。我们的研究结果表明，虽然育种计划成功地提高了块茎产量，但收获后块茎干物质含量和抗病性（山药花叶病毒和炭疽病）在正在开发的材料中并未遵循类似的趋势。这意味着山药育种计划需要在各种性状之间取得平衡，确保产量的增加不会以牺牲食品质量或抗病性为代价。我们的结果强调了持续监测和评估育种计划绩效以及就未来改进重点关注哪些性状做出明智决策的重要性。