TY - JOUR
T1 - Brassinosteroid-Mediated Improvement of Rice Yield and Phosphorus (P) use Efficiency Under P Deficiency
T2 - A Root-Rhizosphere Perspective
AU - Zhu, Kuanyu
AU - Peng, Shiyan
AU - Xu, Zhihan
AU - Shi, Ke
AU - Duanmu, Qingyue
AU - Shen, Xingyu
AU - Xu, Yuemei
AU - Zhang, Yajun
AU - Zhou, Tianyang
AU - Zhang, Weiyang
AU - Xu, Yunji
AU - Gu, Junfei
AU - Zhang, Hao
AU - Wang, Zhiqin
AU - Zhang, Jianhua
AU - Yang, Jianchang
N1 - This work was supported by the National Natural Science Foundation of China (32272198, 32301930), the Ministry of Agriculture and Rural Affairs of China (FSNK202218080316), the National Key Research and Development Program of China (2022YFD2300304) and the Priority Academic Program Development of Jiangsu Higher Education Institutions (PAPD-2020-01).
Publisher Copyright:
© 2025. The Author(s).
PY - 2025/12/5
Y1 - 2025/12/5
N2 - Brassinosteroids (BRs) play important roles in regulating nutrient uptake, and phosphorus (P) deficiency severely limits rice productivity. However, whether and how BRs mediate P use efficiency (PUE), particularly via root-rhizosphere processes, remains unclear. Over three years, we ran two pot experiments in a low-P soil (Olsen-P 6.8 mg kg⁻¹). Experiment 1 (Genotype × P): YG2 (strong low-P tolerant variety) and ZD88 (weak low-P tolerant variety) were grown under no P (0P) and normal P (NP) conditions. Experiment 2 (Chemical application× P): plant roots were irrigated with 2,4-epibrassinolide (2,4-EBL) or a BRs biosynthesis inhibitor under both 0P and NP rates, with distilled water as the control. Results showed that, relative to NP, 0P significantly decreased root BR (2,4-epibrassinolide and 2,8-homobrassinolide) content in both genotypes, with a smaller reduction in YG2 than in ZD88 under 0P. YG2 outperformed ZD88 in grain yield and PUE at both P rates, especially at 0P, mainly due to the enhancement of early-stage (before panicle initiation) P accumulation driven by its elevated BR content. Under 0P, YG2 also exhibited superior root morph-physiological traits, viz. root length, root activity, malate secretion, along with higher pyrroloquinoline quinone biosynthesis protein C (pqqC) gene copies and greater resin-P content in the rhizosphere. At 0P, applying 2,4-EBL increased root BR content, activated BR-signaling gene expression, improved root and rhizosphere traits, and enhanced early-stage P accumulation, whereas applying BRs biosynthesis inhibitor had opposite effects. Applying 2,4-EBL additionally favored recruitment of the phosphate-solubilizing bacterium Massilia. Correlation and structural equation model analyses supported a pathway whereby elevated BR content activated BR signaling and downstream cascades that strengthened root performance and enriched Massilia, thereby increasing absorptive capacity and rhizosphere P supply. Overall, BRs mediate grain yield and PUE by optimizing root-rhizosphere cooperation under P-deficiency conditions.
AB - Brassinosteroids (BRs) play important roles in regulating nutrient uptake, and phosphorus (P) deficiency severely limits rice productivity. However, whether and how BRs mediate P use efficiency (PUE), particularly via root-rhizosphere processes, remains unclear. Over three years, we ran two pot experiments in a low-P soil (Olsen-P 6.8 mg kg⁻¹). Experiment 1 (Genotype × P): YG2 (strong low-P tolerant variety) and ZD88 (weak low-P tolerant variety) were grown under no P (0P) and normal P (NP) conditions. Experiment 2 (Chemical application× P): plant roots were irrigated with 2,4-epibrassinolide (2,4-EBL) or a BRs biosynthesis inhibitor under both 0P and NP rates, with distilled water as the control. Results showed that, relative to NP, 0P significantly decreased root BR (2,4-epibrassinolide and 2,8-homobrassinolide) content in both genotypes, with a smaller reduction in YG2 than in ZD88 under 0P. YG2 outperformed ZD88 in grain yield and PUE at both P rates, especially at 0P, mainly due to the enhancement of early-stage (before panicle initiation) P accumulation driven by its elevated BR content. Under 0P, YG2 also exhibited superior root morph-physiological traits, viz. root length, root activity, malate secretion, along with higher pyrroloquinoline quinone biosynthesis protein C (pqqC) gene copies and greater resin-P content in the rhizosphere. At 0P, applying 2,4-EBL increased root BR content, activated BR-signaling gene expression, improved root and rhizosphere traits, and enhanced early-stage P accumulation, whereas applying BRs biosynthesis inhibitor had opposite effects. Applying 2,4-EBL additionally favored recruitment of the phosphate-solubilizing bacterium Massilia. Correlation and structural equation model analyses supported a pathway whereby elevated BR content activated BR signaling and downstream cascades that strengthened root performance and enriched Massilia, thereby increasing absorptive capacity and rhizosphere P supply. Overall, BRs mediate grain yield and PUE by optimizing root-rhizosphere cooperation under P-deficiency conditions.
KW - Brassinosteroids
KW - Grain yield
KW - P deficiency
KW - P use efficiency
KW - Rice
KW - Root and rhizosphere
UR - https://link.springer.com/article/10.1186/s12284-025-00872-7#Abs1
U2 - 10.1186/s12284-025-00872-7
DO - 10.1186/s12284-025-00872-7
M3 - Journal article
C2 - 41350960
SN - 1939-8425
VL - 19
JO - Rice
JF - Rice
IS - 1
M1 - 2
ER -
