Researchers Find New Candidate Genes for Disease Resistance in Tomato

Tomato (Solanum lycopersicum) is threatened by a number of major diseases worldwide, and developing management practices against them has been difficult. University of Florida researchers, led by Juliana Pereira, aimed to improve tomato disease resistance by overexpressing genes encoding the Arabidopsis thaliana Elongator subunits, AtELP3 and AtELP4.

Overexpression of AtELP3 and AtELP4 significantly enhanced resistance to tomato bacterial speck caused by  Pseudomonas syringae pv. tomato without clear detrimental effects on plant growth and development. Interestingly, the transgenic plants only exhibited resistance to Pst when inoculated through foliar sprays but not through infiltration into the leaf apoplast.

Further analysis revealed that a group of defense-related genes were highly induced after infection in the AtELP4 transgenic tomato plants compared to control plants. This suggests that the enhanced resistance of the transgenic plants may be attributed to elevated induction of defense responses.

Furthermore, the tomato genome contains single-copy genes encoding all six Elongator subunits (SlELPs), which share high similarities with the AtELP genes. The SlELP3 and SlELP4 also complemented the Arabidopsis Atelp3 and Atelp4 knock-out mutants, respectively, suggesting that the AtELP and SlELP genes have similar functions.

These results reveal potential candidate genes for engineering disease resistance in tomato.

For more information, read the article in Frontiers in Plant Science.