Changes in the redox status of tomato fruit play a role in determining the ripening behaviour of tomato varieties
1Division of Genomic Resources, ICAR-National Bureau of Plant and Genetic Resources (NBPGR), Pusa Campus, New Delhi 110 012, India. 2 Division of Plant Physiology, ICAR-Indian Agricultural Research Institute (IARI), New Delhi 110 012, India. 3Division of Basic Sciences, ICAR-Indian Institute of Horticultural Research (IIHR), Hessaraghatta, Lake Post, Bengaluru, Karnataka, 560 089, India. 4Division of Germplasm Conservation, ICAR-National Bureau of Plant and Genetic Resources (NBPGR), Pusa Campus, New Delhi 110 012, India. Corresponding e-mail: vijay_paul_iari@yahoo.com
DOI: https://doi.org/10.37855/jah.2026.v28i01.14
Full text PDF Tomato fruit ripening, being an oxidative phenomenon, is regulated by antioxidants. In this study, the role of non-enzymatic antioxidants was investigated during tomato fruit ripening to determine their contribution to postharvest ripening behaviour across four varieties differing in ripening behaviour. The ripening index (%) of fruits confirmed that varieties Pusa Ruby and Pusa Sadabahar showed fast-ripening behaviour, whereas Pusa Gaurav and Roma showed slow-ripening behaviour. Tomato fruit ripening began with the degradation of chlorophylls and the accumulation of carotenoids, lycopene, vitamin C, total soluble phenols (TSP), total flavonoids (TF) and glutathione (total and reduced). Higher (55.6 to 86.6%) and lower (34.7 to 38.2%) degradation of chlorophyll b along with higher (by 11.8 to 12.0-fold) and lower (by 3.2 to 9.1-fold) accumulation of lycopene fraction (%) in fast- and slow-ripening varieties, respectively, indicated that changes in the levels of antioxidative pigments play a role in deciding ripening behaviour. Progressive increase in TSP, TF and vitamin C was observed in tomato fruits during storage. Fine regulation of ripening behaviour with modulation of glutathione redox status confirmed the differential onset of ripening in fast- and slow-ripening varieties. Early ripening, around the green-mature stage of harvesting, was observed in fast-ripening varieties, whereas it began around 5 days after harvest in slow-ripening varieties. Further, strong associations between the ripening index (%) and levels of non-enzymatic antioxidants during storage also suggest a role in imparting fast- and slow-ripening behaviour to tomato fruits of different varieties.
