Submitted to: International Society of Sugar Cane Technologists Proceedings
Publication Type: Proceedings
Publication Acceptance Date: 2/14/2007
Publication Date: 8/1/2007
Citation: Eggleston, G., Viator, R.P., Grisham, M.P. 2007. Glyphosate ripener effects on the process quality of different sugarcane tissues. In: Proceedings of the International Society of Sugar Cane Technologists, July 29-August 2, 2007, South Africa. 26:1460-1467. Interpretive Summary: Chemical ripener is routinely applied to sugarcane in the U.S. to increase sucrose yields. However, the effect of this application has not been reported before. This paper reports the results of a study on the processing quality of juice from different tissues of two commercial Louisiana varieties. Generally, ripener treatment causes increased delivery of detrimental brown, dried leaves to the factory. The brown, dried leaves contain starch, a polysaccharide that is detrimental to processing. The effect of ripener treatment on processing is denpendent on the sugarcane variety.
Technical Abstract: Currently, there is a dramatic shift world-wide from the harvesting of burnt to green (unburnt) sugarcane, and an associated increase in the delivery of extra trash impurities, i.e., leaves and tops, to factories putting added burdens on processors. The effect of changing to green cane harvesting on processing has not been properly or fully characterized and, therefore, very few solutions to minimize the detrimental processing effects of trash have been developed or implemented. This paper reports the results of a study on the processing quality of juice from different tissues of two commercial Louisiana varieties: LCP 85-384 and HoCP 96-540. The effect of applying a chemical ripener (glyphosate), an important component of sugarcane production management, on different tissues of the plant was also investigated. Juice was extracted from lower stalk (LS), middle stalk (MS), growing point region (GPR), green leaves (GL), and brown, dried leaves (BL), 27 and 53 days after glyphosate treatment (DAT). Generally, with glyphosate treatment there was more BL than with no treatment, and LCP 85-384 delivered more BL to the factory than HoCP 96-540 as BL adhere more tightly to its stalk. Starch was surprisingly discovered in the BL of both varieties indicating that brown, senescing leaves are still metabolically active, store starch, and not necessarily "dead". Starch was generally higher in all tissues of HoCP 96-540 than LCP 85-384. Overall, 53 DAT, starch decreased because of increased cane maturity, but generally less starch occurred in glyphosate-treated LCP 85-384 tissue than non-treated and vice versa for HoCP 96-540. Other differences in processing quality of the different tissues are discussed.