Oilseed rape (Brassica napus) is one of the most important oil crops in the world and shows sensitivity to low phosphorus (P) availability. In many soils, organic P (Po) is the main component of the soil P pool. Po must be mineralised to Pi through phosphatases, and then taken up by plants. However, the relationship between root‐secreted acid phosphatases (APase) and root morphology traits, two important P‐acquisition strategies in response to P deficiency, is unclear among B. napus genotypes. This study aimed to understand their relationship and how they affect P acquisition, which is crucial for the sustainable utilisation of agricultural P resources. This study showed significant genotypic variations in root‐secreted APase activity per unit root fresh weight (SAP) and total root‐secreted APase activity per plant (total SAP) among 350 B. napus genotypes. Seed yield was positively correlated with total SAP but not significantly correlated with SAP. Six root traits of 18 B. napus genotypes with contrasting root biomass were compared under normal Pi, low Pi and Po. Genotypes with longer total root length (TRL) reduced SAP, but those with shorter TRL increased SAP under P deficiency. Additionally, TRL was important in P‐acquisition under three P treatments, and total SAP was also important in P‐acquisition under Po treatment. In conclusion, trade‐offs existed between the two P‐acquisition strategies among B. napus genotypes under P‐deficient conditions. Total SAP was an important root trait under Po conditions. These results might help to breed B. napus with greater P‐acquisition ability under low P availability conditions.

中文翻译：

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甘蓝型油菜根分泌酸性磷酸酶和根形态特征之间的权衡及其对磷获取的贡献

油菜（甘蓝型油菜）是世界上最重要的油料作物之一，对低磷 (P) 利用率非常敏感。在许多土壤中，有机磷（Po）是土壤磷库的主要成分。 Po必须通过磷酸酶矿化为Pi，然后被植物吸收。然而，根分泌酸性磷酸酶（APase）与根形态性状（应对磷缺乏的两种重要的磷获取策略）之间的关系尚不清楚。B. 甘蓝型油菜基因型。本研究旨在了解它们之间的关系以及它们如何影响磷的获取，这对于农业磷资源的可持续利用至关重要。本研究显示 350 个植物中每单位根鲜重 (SAP) 的根分泌 APase 活性和每株植物的总根分泌 APase 活性 (总 SAP) 存在显着的基因型差异B. 甘蓝型油菜基因型。种子产量与总 SAP 呈正相关，但与 SAP 不显着相关。 18 的 6 个根本特征B. 甘蓝型油菜在正常 Pi、低 Pi 和 Po 下比较具有对比根生物量的基因型。总根长 (TRL) 较长的基因型会减少 SAP，但 TRL 较短的基因型会在磷缺乏时增加 SAP。此外，TRL 在三种 P 处理下的 P 获取中很重要，总 SAP 在 Po 处理下的 P 获取中也很重要。总之，两种 P 获取策略之间存在权衡B. 甘蓝型油菜P缺陷条件下的基因型。总 SAP 是 Po 条件下的一个重要根系性状。这些结果可能有助于繁殖B. 甘蓝型油菜在低磷利用率条件下具有更强的磷获取能力。