The effect of low ascorbic acid content on tomato fruit ripening

BALDET, PIERRE; JUST, DANIEL; GANGANELLI, INTI; STEELHEART, CHARLOTTE; ROTHAN CHRISTOPHE; OKABE, YOSHIHIRO; GERGOFF GROZEFF, GUSTAVO ESTEBAN; ALEGRE, MATÍAS LEONEL; BRÈS, CÉCILE; EZURA, HIROSHI; BARTOLI, CARLOS GUILLERMO

PLANTA

SPRINGER

Lugar: Berlin; Año: 2020

0032-0935

Ripening of tomato fruit is associated with several modifications suchas loss of cell wall firmness and transformation of chloroplasts tochromoplasts. Besides a peak in H2O2, reactive oxygenspecies (ROS), are observed at the transition stage. However, the role ofdifferent components of oxidative stress metabolism in fruit ripening has been scarcelyaddressed. Two GDP-L-galactose phosphorylase (GGP) Solanum lycopersicum L cv Micro-Tom mutants which have fruit with lowascorbic acid content (30 % of wild type) were used in this work to unravel theparticipation of ascorbic acid and H2O2 in fruitmaturation. Both GGP mutants show delayed fruit maturation with no peak of H2O2;treatment with ascorbic acid increases its own concentration and acceleratesripening only in mutants to become like wild type plants. Unexpectedly, thetreatment with ascorbic acid increases H2O2 synthesis inboth mutants resembling what is observed in wild type fruit. Exogenoussupplementation with H2O2 decreases its own synthesisdelaying fruit maturation in plants with low ascorbic acid content. The site ofROS production is localized in the chloroplasts of fruit of all genotypes as determinedby confocal microscopy analysis. The results presented here demonstrate thatboth ascorbic acid and H2O2 actively participate intomato fruit ripening.