Sodium toxicity caused by soil salt stress can hamper plant growth. Fei Li
of Nanjing Agricultural University in China, together with a team of
researchers, studied the chrysanthemum (Dendranthema grandiflora) gene
CmHSFA4 and its role in salt stress tolerance.
The team found that the gene was inducible by salt stress and is found
mostly in the nucleus. They then developed transgenic chrysanthemum
overexpressing CmHSFA4 for further analysis of the gene. The transgenics
displayed enhanced tolerance to salt stress. The enhanced tolerance was a
result of limited build up of sodium ions and constant levels of potassium
in the plants. Further analysis revealed that these were done by
upregulation of ion transporters, CmSOS1 and CmHKT2.
These results suggest that CmHSFA4 can confer salinity tolerance in
chrysanthemum by regulating the levels of sodium and potassium ions in