A DEMETER-like DNA demethylase governs tomato fruit ripening.

In plants, genomic DNA methylation which contributes to development and stress responses can be actively removed by DEMETER-like DNA demethylases (DMLs). Indeed, in Arabidopsis DMLs are important for maternal imprinting and endosperm demethylation, but only a few studies demonstrate the developmental roles of active DNA demethylation conclusively in this plant. Here, we show a direct cause and effect relationship between active DNA demethylation mainly mediated by the tomato DML, SlDML2, and fruit ripening- an important developmental process unique to plants.

Effects of exogenous glucose on carotenoid accumulation in tomato leaves.

To investigate the effect of carbohydrate on carotenoid accumulation in leaves, excised plants of tomato (Lycopersicum esculentum var. cerasiformae, wva 106) were supplied with glucose through the transpiration stream for 48 h. We report here that sugar accumulation in leaves led to a decrease of carotenoid content, which was related to the reduction of Chl.

Sucrose deficiency delays lycopene accumulation in tomato fruit pericarp discs.

Tomato (Solanum lycopersicum) fruit ripening is characterized by a massive accumulation of carotenoids (mainly lycopene) as chloroplasts change to chromoplasts. To address the question of the role of sugars in controlling carotenoid accumulation, fruit pericarp discs (mature green fruits) were cultured in vitro in the presence of various sucrose concentrations. A significant difference in soluble sugar content was achieved depending on external sucrose availability.