Phosphorus uptake and rhizosphere properties of alfalfa in response to phosphorus fertilizer types in sandy soil and saline-alkali soil

• Published in: Frontiers in plant science Vol. 15; p. 1377626
• Main Authors: Zhang, Tianchan, Wan, Weifan, Sun, Zhi, Li, Haigang
• Format: Journal Article
• Language: English
• Published: Switzerland Frontiers Media S.A 2024
• Subjects: alfalfa; phosphorus fertilizer; rhizosphere process; saline-alkali soil; sandy soil; soil type; soil type; phosphorus fertilizer; saline-alkali soil; alfalfa; rhizosphere process; sandy soil
• ISSN: 1664-462X; 1664-462X
• DOI: 10.3389/fpls.2024.1377626

Phosphorus (P) fertilizer is critical to maintain a high yield and quality of alfalfa (Medicago sativa L.). There are several fertilizer types and soil types in China, and the application of a single type of P fertilizer may not be suitable for present-day alfalfa production. In order to select the optimal combination of alfalfa and soil type and fertilizer type for improving P utilization efficiency. We conducted a greenhouse pot experiment, calcium superphosphate (SSP), diammonium phosphate (DAP), ammonium polyphosphate (APP), potassium dihydrogen phosphate (KP), and no-fertilizer control treatments were applied to alfalfa in sandy and saline-alkali soils. The response of alfalfa root morphology and rhizosphere processes to different P fertilizers was investigated. The results showed that shoot biomass of alfalfa was slightly higher in sandy soil than in saline-alkali soil. Shoot biomass of alfalfa increased by 223%-354% in sandy soil under P treatments compared with the control, and total root length increased significantly by 74% and 53% in DAP and SSP treatments, respectively. In saline-alkali soil, alfalfa shoot biomass was significantly increased by 229% and 275% in KP and DAP treatments, and total root length was increased by 109% only in DAP treatment. Net P uptake of alfalfa in DAP treatment was the highest in both soils, which were 0.73 and 0.54 mg plant , respectively. Alfalfa shoot P concentration was significantly positively correlated with shoot and root biomass ( < 0.05, 0.01 or 0.001) whereas negatively correlated with acid phosphatase concentration ( < 0.05). Improvement of plant growth and P uptake induced by P fertilizer application was greater in sandy soil than in saline-alkali soil. DAP and KP was the most efficient P fertilizers in both sandy soil and saline-alkali soil.