|Cade-Menun, Barbara - STANFORD UNIVERSITY|
|Toor, Gurpal - UNIV OF DELAWARE|
|Sims, J Thomas - UNIV OF DELAWARE|
Submitted to: ASA-CSSA-SSSA Annual Meeting Abstracts
Publication Type: Abstract Only
Publication Acceptance Date: September 10, 2005
Publication Date: November 6, 2005
Citation: He, Z., Cade-Menun, B.J., Toor, G.S., Honeycutt, C.W., Sims, J. 2005. Comparison of P forms in animal manure identified by enzymatic hydrolysis and solution P-31 nmr. ASA-CSSA-SSSA Annual Meeting Abstracts. ON CD Technical Abstract: Both enzymatic hydrolysis and solution phosphorus-31 NMR spectroscopy have been used in characterizing P forms in animal manure. To date, however, there are no reports comparing the P identified by the two methods. In this study, P in 0.25 M NaOH/0.05 M EDTA extracts of dairy manure and poultry litter was comparatively investigated by the two methods. Enzymatic hydrolysis revealed that the extracted P in a dairy manure was 56% inorganic P, 9% simple monoester P, 6% polynucleotide-like P, 10% phytate-like P, and 18% non-hydrolyzable P. The P forms in the extracts of a poultry manure were 71% inorganic P, 1% monoester P, 3% polynucleotide-like P, 15% phytate-like P, and 9% non-hydrolyzable P. NMR analysis indicated that total P in the dairy manure extracts was 64% inorganic P, 6% phytic acid, and 14% other monoesters. Phospholipids were 6% and DNA, phosphonates, pyrophosphate and polyphosphates constituted 1% each. The P distribution in poultry manure was 63% inorganic P, 24% phytic acid, 6% other monoesters, 3% phospholipids and 1% DNA. These observations show that P forms detected by the two methods were not always the same due to different identities and/or stability to hydrolysis. Thus the two methods may complement one another to provide a full spectrum of manure P characterization.