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Global interest in sugarcane has increased significantly in recent years due to its economic impact on sustainable energy production. Sugarcane breeding and better agronomic practices have contributed to a huge increase in sugarcane yield in the last 30 years. Additional increases in sugarcane yield are expected to result from the use of biotechnology tools in the near future. Genetically modified (GM) sugarcane that incorporates genes to increase resistance to biotic and abiotic stresses could play a major role in achieving this goal. However, to bring GM sugarcane to the market, it is necessary to follow a regulatory process that will evaluate the environmental and health impacts of this crop. The regulatory review process is usually accomplished through a comparison of the biology and composition of the GM cultivar and a non-GM counterpart. This review intends to provide information on non-GM sugarcane biology, genetics, breeding, agronomic management, processing, products and byproducts, as well as the current technologies used to develop GM sugarcane, with the aim of assisting regulators in the decision-making process regarding the commercial release of GM sugarcane cultivars.

Sucrose is the major product of photosynthesis in many higher plants. It is transported from the source tissue through the phloem to various sink tissues to support plant growth, development and reproduction. Knowledge on the signal transduction pathways involved in sucrose synthesis in mature leaves is limited. Using a microarray approach, we analyzed the expression profiles of 1920 sugarcane genes encoding signal transduction elements, transcription factors and stress-related proteins. We used individuals from a population segregating for sugar content and gene expression profiles were obtained from seven individuals with highest and seven with lowest sugar content. Surprisingly, from the 24 differentially expressed genes, 19 were more expressed in plants containing low-sugar content. Three of these genes encoded 14-3-3 like proteins, which have been found to reduce sucrose phosphate synthase (SPS) activity. Another encoded an SNF1-related protein similar to a protein kinase that phosphorylates SPS in vitro making it a target for the interaction with 14-3-3 proteins. The up-regulation of eight stress related genes in the lower sugar content plants supports a view that sugar levels modulate a complex signal transduction network that seems to involve responses that are related to stress. Evidence that hormone signaling is related to the sucrose content was also found. These data reinforced the usefulness of genomic approaches to uncover how sucrose metabolism can be regulated in sugarcane.