University of Florida

Mabry McCray

Scientist, Agronomy
Specialty: Sugarcane nutrition

Research Focus

The objectives of my research program are to determine useful relationships between sugarcane yield and soil and plant nutrients, to update IFAS fertilizer recommendations for phosphorus and other nutrients, and to evaluate fertilizer and amendment needs required to sustain sugarcane as a viable crop as there are changes in cropping systems or environmental conditions in the area. In my extension program I work closely with other researchers and extension agents to promote increased efficiency of nutrients and cost-effective use of fertilizers and amendments by providing growers with effective nutrient management information and access to reliable soil and leaf analytical services. We also promote best management practices that will enable growers to achieve optimum economic yields while protecting water quality.

Active Projects

  • Leaf nutrient analysis for diagnosis and nutrient management
  • Phosphorus soil-test calibration on organic soils
  • Silicon soil-test calibration on organic and mineral soils
  • Nitrogen rate study on mineral soils
  • Elemental sulfur study on organic soils
  • Organic amendments on mineral soils
  • Lysimeter study of vinasse (ethanol by-product) application on organic soil
  • Potassium rate study on organic soils

Web Sites

DRIS Calculator is available on the EREC web site (40KB zip). This is an Excel spreadsheet that converts sugarcane leaf nutrient concentrations into DRIS indices which provides additional information about nutrient balance.

Selected Publications

  • McCray, J. M., and S. Ji. 2012. Calibration of sugarcane response to calcium silicate on Florida Histosols. J. Plant Nutrition. In press.
  • McCray, J. M., R. W. Rice, Y. Luo, and S. Ji. 2012. Phosphorus fertilizer calibration for sugarcane on Everglades Histosols. Commun. Soil Sci. Plant Anal. In press.
  • McCray, J. M., A. L. Wright, Y. Luo, and S. Ji. 2012. Soil phosphorus forms related to extractable phosphorus in the Everglades Agricultural Area. Soil Sci. 177:31-38.
  • Ye, R.*, J. M. McCray, and A. L. Wright. 2011. Microbial response of a calcareous Histosol to sulfur amendment. Soil Sci. 176:479-486.
  • Ye, R.*, A. L. Wright, and J. M. McCray. 2011. Seasonal changes in nutrient availability for sulfur-amended Everglades soils under sugarcane. J. Plant Nutrition. 34:2095-2113.
  • McCray, J. M., S. Ji., G. Powell, G. Montes, and R. Perdomo. 2010. Sugarcane response to DRIS-based fertilizer supplements in Florida. J. Agron. Crop Sci. 196:66-75.
  • McCray, J. M., S. Ji, G. Powell, G. Montes, R. Perdomo, and Y. Luo. 2010. Boundary lines used to determine sugarcane production limits at leaf nutrient concentrations less than optimum. Commun. Soil Sci. Plant Anal. 41:606-622.
  • McCray, J. M., R. W. Rice, Y. Luo, and S. Ji. 2010. Sugarcane response to phosphorus fertilizer on Everglades Histosols. Agron. J. 102:1468-1477.
  • Ye, R.*, A. L. Wright, J. M. McCray, K. R. Reddy, and L. Young. 2010. Sulfur-induced changes in phosphorus distribution in Everglades Agricultural Area soils. Nutrient Cycling in Agroecosystems 87:127-135.
  • Ye, R.*, A. L. Wright, W. H. Orem, and J. M. McCray. 2010. Sulfur distribution and transformations in Everglades Agricultural Area soil as influenced by sulfur amendment. Soil Sci. 175:263-269.
  • McCray, J. M., S. Ji, G. Powell, G. Montes, R. Perdomo, and Y. Luo. 2009. Seasonal concentrations of leaf nutrients in Florida sugarcane. Sugar Cane International 27(1):17-24.
  • Gilbert, R. A., D. R. Morris, C. R. Rainbolt, J. M. McCray, R. E. Perdomo, B. Eiland, G. Powell, and G. Montes. 2008. Sugarcane response to mill mud, fertilizer, and soybean nutrient sources on a sandy soil. Agron. J. 100:845-854.
  • Gilbert, R. A., C. R. Rainbolt, D. R. Morris, and J. M. McCray. 2008. Sugarcane nutrient content, growth and yield responses to a three-month summer flood. Agric. Water Management 95:283-291

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