Tomato fruit is an important and popular commodity worldwide. One of the main challenges for the fresh market tomato industry is postharvest deterioration, which is mainly determined by the rate of softening. This rate can affect tomato shelf-life, pathogen susceptibility, and fruit waste. The softening rate is regulated by multiple factors, but mainly by the pectin composition of the cell wall, which is remodeled, disassembled, and solubilized by enzymes during fruit ripening; a process that induces and determines the fruit softening in fleshy fruits. The main pectin-degrading enzymes that act on the pectin backbone are Polygalacturonases (PG) and pectate lyases (PL). In this study, we generated a double CRISPR knockout PGPL. We investigated the combined functions of SlPG2a and SlPL on fruit quality traits in postharvest, including shelf-life attributes like firmness and water loss, fruit marketability, and disease incidence. We also assessed additional attributes impacting consumer acceptance, such as taste and aroma. Our findings revealed that the tomato ripening enzymes SlPG2a and SlPL act additively, significantly affecting fruit firmness and shelf-life. Additionally, aspects of fruit quality, such as external color, sugar: acid ratio, and aroma volatiles, were improved or not affected in the double CRISPR knockout PGPL when compared to control. The discoveries of this research provide new insights into the influence of pectin backbone degradation on fruit physiology and postharvest quality, which can be used in crop improvement programs to make fruit more resilient in the supply chain without compromising consumer-based quality traits.
