TITLE:
Phosphorus Fertilization Differentially Influences Fatty Acids, Protein, and Oil in Soybean
AUTHORS:
Xinhua Yin, Nacer Bellaloui, Angela M. McClure, Don D. Tyler, Alemu Mengistu
KEYWORDS:
Phosphorus, Fatty Acids, Protein, Oil, Yield, Soybean
JOURNAL NAME:
American Journal of Plant Sciences,
Vol.7 No.14,
October
17,
2016
ABSTRACT: Information is limited about phosphorus (P)
fertilization effects on soybean seed composition. A field experiment was
conducted to investigate the effects of P application rates on the
concentrations of various fatty acids, protein, and oil in soybean under
no-tillage on low and high testing P soils at Jackson and Milan, Tennessee from
2008 through 2011. Five P rates 0, 10, 20, 30, and 40 kg·P·ha-1 plus
the recommended P fertilizer rate based on soil P testing results were arranged
in a randomized complete block design with four replicates. Protein, oil, and
fatty acid concentrations in seed responded differently to P fertilization. In
general, protein concentrations were enhanced but oil levels decreased with
increased P application rate. Palmitic and oleic concentrations responded
positively to P application rate up to a certain level. However, the response
of linolenic acid concentration was inconsistent (negative or positive).
Stearic concentration was not influenced by P fertilization. Application of 10
kg·P·ha-1 resulted in higher production of protein and palmitic,
oleic, and linolenic acids than zero P and the higher P application rates as
well on the P deficient soil. Excessive P application rates could lower seed
yield and the quality of some attributes in seed. In conclusion, linoleic acid
concentration, a key quality attribute in soybean seed for human and animal
consumption, can sometimes be enhanced by P fertilization; the indigenous soil
P level and P application rate should be taken into account in breeding soybean
cultivars with low linolenic acid level.