Researchers
from the University of Cape Town's (UCT's) Department of Botany are aiming to design crop
plants that are more disease and drought-resistant.
Associate
Professor Jill Farrant and her team are investigating the genes involved in desiccation
tolerance and immunity to disease.
The team
are using "resurrection plants", a type unique to southern Africa, which can
tolerate extreme water loss for up to two years. Once watered, they "resurrect",
turning green in a few days.
"Water
has become a limiting factor in world agriculture," said Prof. Farrant. "Most
crops are sensitive to even mild dehydration stress. There are, however, a few genera of
plants unique to southern Africa called 'resurrection plants', which can tolerate extreme
water loss or desiccation. Their unique ability to withstand severe water loss (greater
than 90%) makes them an ideal system to study."
Xerophyta
viscose and Xerophyta humilis, representative of the monocotyledonous
resurrection plants, are being used to isolate genes that are associated with desiccation
stress tolerance.
The team
have isolated a number of genes, using approaches such as differential screening and
microarray analysis of gene libraries, which are unregulated during drying and/or
rehydration of these plants. In collaboration with Prof. Jennifer Thomson, these genes are
being transferred into model "crop" species (Digitaria Sanguinalis and Arabidopsis
thaliana) and will ultimately be used to transform crops such as maize, sorghum,
wheat and rice for improved drought tolerance.
The
project team includes Associate Professor Nicci Illing, Dr Katherine Denby and Dr
Sagadevan Mundree from the Department of Molecular and Cell Biology.