The majority of paddy fields in sub‐Saharan Africa (SSA) are characterized by nutrient‐poor soils. In such fields, tillering in rice (Oryza sativa L.) plants is severely restricted, which results in a reduced number of panicles and thus a decrease in grain yield. In this study, we evaluated the effects of a quantitative trait locus (QTL), associated with number of panicles and referred as MP3, on rice growth and grain yield in nutrient‐poor soils in Madagascar. We used a high‐yielding rice cultivar, Takanari, and its near‐isogenic line bearing the MP3 allele (NIL‐MP3). A pot experiment with various P application rates demonstrated vigorous tillering in NIL‐MP3 compared to Takanari from the early vegetative stage even under low P levels. This led to enlarged leaf area and thus increased biomass. We then conducted multiple field trials with a total of 12 experimental conditions using the two varieties. The experiments led to a range of grain yield from 1.3 to 4.1 t ha⁻¹ and a range in number of panicles from 107 to 270 m⁻². The results revealed that NIL‐MP3 produced a greater number of panicles and spikelets m⁻² (19 and 12%, respectively) than Takanari across all 12 experiments. Grain yield increased in NIL‐MP3 under some experimental conditions. This study is the first of its kind to demonstrate that MP3 increased number of panicles and spikelets and grain yield in the nutrient‐poor and low‐yielding soils of SSA. Thus, we conclude that MP3 could become a prominent genetic resource for the improvement of rice yields in SSA.

中文翻译：

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马达加斯加营养不良土壤定量性状位点MP3对穗数和水稻生产力的影响

撒哈拉以南非洲（SSA）的大多数稻田以营养贫瘠的土壤为特征。在这样的田地中，水稻（Oryza sativa L.）植物的分till受到严格限制，这导致穗数减少，从而导致谷物产量下降。在这项研究中，我们评估了与穗数相关并称为MP3的数量性状基因座（QTL）对马达加斯加营养不良土壤中水稻生长和谷物产量的影响。我们使用了高产水稻品种Takanari及其带有MP3等位基因（NIL- MP3）的近等基因系。在不同的磷施用量下进行的盆栽试验表明，NIL- MP3中的分till剧烈即使在低磷水平下，从早期的营养阶段相比，也比Takanari高 这导致叶面积增大，从而增加了生物量。然后，我们使用这两个品种在总共12种实验条件下进行了多次田间试验。实验导致谷物产量在1.3至4.1t ha ^-1的范围内并且穗数在107至270m ^{-2的范围内}。结果显示，在所有12个实验中，NIL- MP3产生的穗和小穗m ^-2的数量（分别为Takanari）为19和12％。在某些实验条件下，NIL- MP3中的谷物产量增加。这项研究是首次证明MP3SSA的营养贫瘠和低产土壤中的穗和小穗数量增加，谷物产量增加。因此，我们得出结论，MP3可以成为提高SSA水稻产量的重要遗传资源。