Soil Phosphorous Status and Phosphorus Cycling as Influenced by Soybean Genotypes on an Acidic Low-Phosphorus Soil of Southern China

Abstract

Low soil phosphorus (P) availability is the primary limiting factor to soybean production in southern China. Field experiments with P-efficient (BX10 and BX11) and P-inefficient (BD2 and GD3) soybean genotypes were conducted to study the effects of soybean cultivation on P status and budget. The results showed that after four seasons of cultivation (2003–5), zero application of P resulted in a decrease of soil-available P and total P but high-P (80 kg ha⁻¹) treatment resulted in an increase; there were no significant differences among genotypes. All genotypes had deficit of P under zero application of P, P-efficient genotypes had a larger deficit, and there was significant difference between BX10 and BD2. There was surplus P under high-P application, but there were no significant differences among soybean genotypes. These findings imply that it is necessary to apply P fertilizer for P-efficient genotypes although they can better adapt to low-P soil.

Keywords:

• Available P
• P budget
• P cycling
• P efficiency
• P loss

Acknowledgments

This study was financially supported by grants from the McKnight Foundation Collaborative Crop Research Program. We are grateful to Dr. Jonathan Lynch (Pennsylvania State University) for helpful comments and suggestions on the manuscript.