Sugarcane Response to Water-Table Depth and Periodic Flooding.
Barry Glaz and Dolen Morris. USDA-ARS, USDA-ARS, 12990 US Highway 441, Canal Point, FL 33438
Sugarcane (Saccharum spp.) in the Everglades Agricultural Area (EAA) of Florida is often exposed to high water tables and periodic floods. Growers are concerned that elevated water tables for prolonged periods and during certain phases of growth reduce yields. However, these wet conditions help reduce oxidation of the organic soils of the EAA, and reductions in both soil oxidation and drainage help decrease unwanted phosphorus discharge to natural areas of the Everglades near the EAA. The purpose of this study was to determine the effects, on sugarcane cultivars CP 88-1762, CP 89-2143, CP 89-2376, and CP 96-1252, of water-table depths of 16 and 45 cm with and without 1-week periodic floods applied every 3 weeks during summers. The experiment was planted in lysimeters at Canal Point, Florida in 2004 and harvested the following 2 years in the plant and first-ratoon crops. In the plant crop, theoretical recoverable sucrose (TRS), measured as g sucrose per kg cane, was increased by the 16-cm water-table depth. In the first-ratoon crop, water table did not affect TRS. In the plant-cane and first-ratoon crops, periodic flooding did not reduce yields if the drainage depth was 45 cm. Also, cane and sucrose yields were higher with periodic flooding and drainage at 45 cm compared with a continuous water-table depth of 16 cm. That cane and sucrose yields were not reduced by periodic flooding if drainage was to 45 cm but yields of both traits were reduced by continuously drained water-table depths of 16 cm, suggests that sugarcane roots function well with periodic flooding but may not grow well from drained soil into saturated soil.