CALIBRATION OF SUGARCANE RESPONSE TO CALCIUM SILICATE ON FLORIDA HISTOSOLS

Abstract

Silicon is considered a beneficial nutrient for sugarcane (Saccharum spp.) and yield responses to Si applications on Florida organic soils have been well documented. Growers need calibrated Si recommendations to be able to make cost-effective decisions regarding Si applications. The objective of this study was to develop a soil-test Si calibration based on yield responses to Ca silicate on Everglades Histosols. Twelve paired commercial field comparisons and three small-plot tests of Ca silicate application were conducted. Strong responses in t cane ha⁻¹ and t sucrose ha⁻¹ were determined with acetic acid-extractable soil Si <15 g m⁻³, with some response to approximately 25 g m⁻³. Recommendations were developed over this range with a maximum Ca silicate rate of 6.7 t ha⁻¹. Optimum leaf Si concentration was determined to be ≥ 6.0 g kg⁻¹, with 0.95 and 0.80 relative yield at 5.0 and 2.5 g kg⁻¹, respectively.

Keywords:

• calcium silicate
• calibration
• Histosols
• leaf analysis
• nutrient management
• rice
• silicon
• slag
• sugarcane

ACKNOWLEDGMENTS

The authors would like to thank the following growers for their participation and support of the study: Florida Crystals Corporation (FC), United States Sugar Corporation (USSC), and Sugar Cane Growers Cooperative (SCGC). The authors also gratefully acknowledge the assistance of Robert Taylor (SCGC), Gerald Powell (FC), German Montes (FC), Qian Hou (USSC), and Bruce Hutcheson (formerly of USSC) in data collection and laboratory analysis. The study was supported by donations from the Florida Sugar Cane League, Inc.—Sugarcane Industry Research Committee and Calcium Silicate Corporation. Dolomite for some tests was donated by AgLime Sales, Inc. Fertilizer for some tests was donated by Wedgworth's, Inc.