Several different approaches to improve the stress tolerance of plants by foreign gene transfer have been attempted. The most consistently successful approach is the introduction of genes encoding enzymes that catalyse the conversion of a naturally occurring substrate into a product with osmoprotective properties. Other important genes encode membrane-modifying enzymes; radical-scavenging enzymes; stress-induced proteins; and hypoxia/anoxia-reducing proteins.

Improved Plants

This section contains brief summaries of experiments where successful stress tolerant plants have been developed.

Phytoremediation

Phytoremediation is a relatively new approach to removing contaminants from the environment. It may be defined as the use of plants to remove, destroy or sequester hazardous substances from the environment. It involves using plants that are stress tolerant to a varitey of compounds which are sometimes found at very high, toxic levels.