Sugarcane (Saccharum X officinarum): A Reference Study for the Regulation of Genetically Modified Cultivars in Brazil

Abstract

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.

Fig. 1

Sugarcane production in regions of Brazil (Source: Conab 2009)

Fig. 2

Kuijper’s leaf numbering system (1915)

Fig. 3

Diagram of a sugarcane propagule: a evident propagule, cupulate coma, empty pedicel and rachilla plus sessile spikelet. The other figures depict the different parts of the spikelet. b Glume I. c Glume II. d Palea. e Flower with two lodicules, three stamens, and gynoecium with ovary and two feathered stigmas (Illustration: Klei Sousa)

Fig. 4

Sugarcane caryopses. Note the presence of the remains of styles at the tip of the caryopsis and the differentiated embryo region (at the opposite extremity of the style remains) (Photograph: Alellyx)

Fig. 5

Flowchart of a sugarcane breeding program. T1: seedling selection. T2: clone selection. T3: local trial. T4: regional trial. Source: CanaVialis

Fig. 6

Sugarcane crossing conducted under domes (lanterns). Source: CanaVialis

Fig. 7

Sugarcane phenological cycle. a Stalk pieces used in planting; b Beginning of bud sprouting and rooting; c Tillering initiation; d Intense tillering; e Beginning of maturation; f Manufacturable stalks in optimal sucrose concentration; g Harvesting; h Ratoon sprouting. Illustration: Rogério Lupo

Fig. 8

Sugarcane industrial processing

Fig. 9

Flow chart of artisanal sugarcane processing