Transgenic Plant Production & Development

Introduction

Transgenic plant production & development has made great advances since the birth of genetic engineering in the early seventies. The various techniques have enabled the modification of an array of agronomically important characteristics, including seed storage products (Knauf, 1987), fatty acid content of the oil, herbicide, disease & pest resistance, as well as other growth traits. However, the stability of transgene expression and inheritance must first be established before the introduction of commercial varieties.

Brassica oilseed crops have proven to be one of the few commercially important crop plants to respond to all the biotechnologies. Fortunately anther and microspore cultures are now routinely used in breeding programmes to produce pure breeding double haploid plants.

Protoplast fusion has also been used in B. napus to combine successfully in a single plant, with the introduction of cytoplasmically inherited traits such as resistance to the triazine family and cytoplasmic male sterility (Downey, 1990).

Transformation is providing numerous opportunities to modify the rapeseed germ line, with its ability to integrate many different genes from outside the Brassica gene pool.

The modification of the major existing oilseed crops to synthesise novel and improved types of oils (industrial uses) can be achieved by the insertion of new genes, or the selective removal or deactivation of present genes in order to modify the lipid biosynthetic pathways (Knauf, 1987). Early work involved the manipulation of triacylglycerol biosynthesis, by two mechanisms: