Sugarcane Genotype Selection for Sand Soils in Florida.

Selection of high yielding sugarcane (Saccharum spp.) genotypes in Florida has been more successful for organic soils than for sand soils. The purpose of this study was to compare the performance of sugarcane genotypes on sand soils with and without mill mud added at the rate of 1510 m³ ha^-1. Mill mud, a by-product organic waste produced from the clarification of sugarcane juice, is rich in N, P, K, Ca, and Mg. In Florida, mill mud is made up largely of the muck soils that come through the mill with the sugarcane. In a field test, 31 sugarcane genotypes were planted as subplots in a sand soil with two soil treatments (with or without mill mud) as main plots. Cane and sucrose yields were determined about 1 year after planting.  The CV for sucrose yield was 26.9% with mill mud compared with 39.9% without mill mud. The mill mud caused a decrease in recoverable sucrose of 20 g kg^-1. However, the mill mud increased cane and sucrose yields by 113 and 11 Mg ha^-1, respectively. Genotypes CL 90-4725, CP 00-1446, and CP 01-1372 had higher than average cane and sucrose yields with added mill mud, but mediocre yields without mill mud. CPCL 01-0877 was high ranking on the sand soil without mill mud and a low ranking genotype with added mill mud. Previous research indicated that CL 90-4725, CP 00-1446, CP 01-1372, and CPCL 01-0877 yielded well on sand soils. However, perhaps due to the increased variability on the sand soil without mill mud, the added mill mud in this study was necessary to identify CL 90-4725, CP 00-1446, and CP 01-1372 as high yielding genotypes. Conversely, the added mill mud detracted in the identification of CPCL 01-0877 as a high-yielding genotype on sand soils.