Understanding the reproductive biology and ecology of sugarcane to manage the safe release of genetically modified cultivars

Abstract

This project set out to obtain basic and previously unavailable information on the ecology and sexual reproduction of sugarcane primarily so advances in sugarcane biotechnology can be utilised to the benefit of the Australian sugarcane industry and the broader Australian economy. The production and commercialisation of genetically modified (GM) sugarcane has attracted increased international interest in recent years, and this has been exemplified by significant, sustained investment in sugarcane biotechnology by large national and international companies. To commercialise GM sugarcane, the proposed cane has to undergo rigorous regulatory assessment including safety to humans and the environment. A significant part of this assessment relates to how a given sugarcane clone functions in the environment (s) where it will be grown, and the likelihood and impact of transfer of the modified trait to other commercial sugarcane or other sympatric sexually compatible species. While such assessments are performed for each proposed GM sugarcane cultivar under consideration, general information about the sexual reproduction and ecology of sugarcane is also important to help understand potential hazards. For sugarcane, this basic information is scant, largely because the stalk not the seed is the harvested product (i.e. sugarcane is vegetatively propagated) and so the sexual reproduction process have not previously been studied in commercially grown sugarcane. This project undertook a series of studies to help fill the ‘information void’ on sugarcane. The project involved several surveys and experiments using cane in farmers’ fields to understand the level of flowering and viable seed production under commercial production. Species that could be sexually compatible with sugarcane were determined through analysis of the breeding literature to see what crosses had been achieved with human intervention. This was followed by comparison with botanical records to determine which of the potential species were present in sugar growing regions.