Phosphorus Deficiency Delays the Onset of Nodule Function in Soybean

• Published in: Journal of plant nutrition 2007-09, Vol.30 (9), p.1341-1353
• Main Authors: Qiao, Yunfa, Tang, Caixian, Han, Xiaozeng, Miao, Sujie
• Format: Article
• Language: English
• Subjects: Agronomy. Soil science and plant productions; Biological and medical sciences; Economic plant physiology; fixation; Fundamental and applied biological sciences. Psychology; Glycine max; Metabolism; Metabolism. Physicochemical requirements; nodule formation; Nutrition. Photosynthesis. Respiration. Metabolism; P and N interaction; P deficiency; Plant physiology and development
• ISSN: 0190-4167; 1532-4087
• DOI: 10.1080/01904160701555325

Effects of phosphorus (P) deficiency on nodulation were examined in soybean grown in nutrient solution for 7 weeks. Increasing P supply increased shoot growth of nitrogen (N 2 )-fixing plants from week 5 and that of nitrate-fed plant from week 4 after treatment. Nitrogen (N 2 )-fixing plants had a greater P requirement for maximum growth at week 5. Increasing P supply from 1 to 16 μ M increased N concentration in N 2 -fixing plants at week 4 but did not affect it from week 5. By contrast, P deficiency increased N concentration in nitrate-fed plants. Increasing P supply improved nodule formation from week 3. Nodule mass was affected more by P supply than nodule number, which, in turn, was affected more than plant growth. However, P supply did not decrease nodule specific N 2 fixation from week 5. The results suggest that P deficiency impaired symbiotic N 2 fixation through delaying onset of nodule function and decreasing nodule development.