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Phosphorus Soil Test Correlation to Sugarcane Grown on Histosols in the Everglades
Author(s) -
Korndörfer G. H.,
Anderson D. L.,
Portier K. M.,
Hanlon E. A.
Publication year - 1995
Publication title -
soil science society of america journal
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.836
H-Index - 168
eISSN - 1435-0661
pISSN - 0361-5995
DOI - 10.2136/sssaj1995.03615995005900060021x
Subject(s) - histosol , phosphorus , soil water , agronomy , crop , soil test , acetic acid , yield (engineering) , crop yield , cultivar , chemistry , environmental science , soil organic matter , biology , soil science , organic chemistry , soil biodiversity , biochemistry , materials science , metallurgy
Sugarcane ( Saccharum spp.) in Florida is principally grown on Histosols in the Everglades Agricultural Area. Soil‐test‐based P fertilization recommendations have not been addressed since the 1970s. The objectives of this research were to evaluate the most acceptable soil test P extractant that best correlates to crop yield, and to define soil test P groupings associated with crop response to applied P. Results will be used in the future to recalibrate soil test data to yield and rate of P application. Phosphorus trials were conducted at four sites on organic soils between 1968 and 1972 and additionally at eight sites on organic soils between 1982 and 1990. Phosphorus applications ranging from 0 to 98 kg P ha −1 were broadcast or row‐applied in combination with different cultivars, and/or K, Si, or S rates at 12 sites (multiple experiments used per site per crop). The effectiveness of water, acetic acid, and Mehlich‐1 extractable soil P as yield response predictors was determined. Acetic acid extractable P was more highly correlated to sugar and cane yields ( r = 0.72* and 0.63**, respectively) than water‐extractable P ( r = 0.27** and 0.39**, respectively). Mehlich‐1 extractable P was poorly correlated to sugar ( r = 0.25*) and cane ( r = 0.05 ns ) yields. Acetic acid extractable P was selected as the best‐suited extractant related to crop yield response to P fertilization. Soil test calibration curves (i.e., relative yield as a function of acetic acid extractable P) were determined from the choice of seven types of regression models, in which the reciprocal function was chosen with the highest coefficient of determination ( R 2 ) and minimized residuals. Soil acetic acid extractable P criteria were developed to define soil test level groups associated with yield response conditions: low soil test levels ranged from 0 to 9 mg L −1 , medium from 9 to 39 mg L −1 , and high exceeded 39 mg P L −1 .