Silencing of SlPL Gene in Tomato Confers Enhanced Fruit Firmness

Pectate lyase genes have been documented as excellent candidates for improvement of fruit firmness. However, this approach in regulating fruit postharvest deterioration has not been fully explored. Lu Yang from Chongqing University in China, along with colleagues, identified pectate lyase genes in tomato and focused on the pectate lyase gene SlPL.

RNA interference of SlPL resulted in enhanced fruit firmness and changes in pericarp cells. Furthermore, the SlPL-RNAi fruit demonstrated greater anti-rotting and pathogen-resisting ability. Compared to wild types, the SlPL-RNAi fruit exhibited higher levels of cellulose and hemicellulose, while pectin levels were lower.

The activities of peroxidase, superoxide dismutase and catalase were also higher in SlPL-RNAi fruit. RNA-sequencing results showed large amounts of differentially expressed genes involved in hormone signalling, cell wall modification, oxidative stress, and pathogen resistance.

These demonstrate that pectate lyase plays an important role in both fruit softening and pathogen resistance. This could be a foundation for improvement of postharvest fruit preservation in tomato and other fleshy fruits.

For more information on the study, read the article in Plant Biotechnology Journal.