Use of Cell and Molecular Genetic Manipulation to Improve Pasture Plants

Cell culture and genetic engineering techmques can be used to develop improved pasture plants. To utltise these methods we have developed procedures for regenerating plants from tissue cultures of perennial ryegrass and white clover. In both, the plant genotype influences regeneration capacity. There was significant genetic variation among regenerated perennial ryegrass plants in a wde range of characteristics. Most of the regenerants were resIstant to crown rust and this trait was highly heritable. This rust resistance is being used to breed a new ryegrass cultwar. A system for introducing cloned genes into white clover is described. This capability is bemg used to incorporate genes with the potential to improve nutritional quality and pest resistance. Other possibilities for engineering genetic improvements in white clover, genes conferring herbicide tolerance and resistance to white clover mosaic wrus, are briefly outlined.