Sugar Composition and Concentrations in Sugarcane Juice As Affected By Sampling Date and Internode Position.

Sugarcane (Saccharum spp. hybrids) harvest season lasts about six months from late-October through mid-April in Florida. Cane juice sugar concentration and composition are important for sucrose yield and profits, however research is lacking on the influence of harvesting time and intermodal position in the commercial varieties in Florida. Stalk juice samples were collected monthly from mid-October through February in four different internodes [Nodes 5 and 10 from ground and Nodes 1 and 5 below the top visible dewlap (TVD) leaf from top] of CP 00-1101 and CP 01-1372 sugarcane cultivars to identify dynamics of juice Brix values, sugar composition, and concentrations as affected by sampling date and internode position. Sampling date and internode position significantly affected sugar composition and concentration. As the stalk internodes from near ground level moved up to the top, juice reducing sugar (glucose and fructose) concentration increased and sucrose level decreased significantly. Although juice sucrose concentration did not differ between two cultivars at most sampling dates, CP 01-1372 had significantly high reducing sugar concentration in juice as compared with CP 00-1101, especially in October through December. Therefore, early harvesting CP 01-1372 (second most cultivated variety in the Florida sugarcane production in 2015 may cause reduction in sucrose yield and profits due to high reducing sugar concentration in juice. Results indicated that variable consequences exist in juice sugar composition and concentration among harvest dates in the Florida sugarcane varieties.