Tomato Fruits Regulating Petal Senescence and Affecting Levels of UV-B Absorbing Pigments and Proline in Cut Flowers of Calendula and Two Species of Chrysanthemum

The study was aimed to find out how any exogenous source of ethylene like ‘just ripe’ tomato fruit could regulate petal senescence in some common ornamental cut flowers like Calendula officinalis and two species of Chrysanthemum (C. dendranthema grandiflorum and C. coronarium) where no significant ethylene production has been recorded during senescence. Flowers placed in distilled water as holding solution have ‘just ripe’ tomato fruit and covered with a bell jar showed a marked decline in flower diameter, fresh weight, cumulative uptake of vase solution and vase life in comparison to sets maintained in similar manner without fruit. Presence of fruit has induced greater magnitude of lipid peroxidation in all the flower petals. Between initial and final day, a sharp decrease was noticed in the amount of protein and UV-B absorbing pigments specially in those sets having fruit. It was interesting to note a small decrease in UV-B absorbing pigments in the petals where no tomato fruit was kept. The difference in the amount of UV-B absorbing flavonoids was smaller between two sets (flower with and without ‘just ripe’ tomato fruit) in Calendula petals whereas it was much greater in Chrysanthemum. Amount of proline increased in cut flowers on last day but the increment was of lesser magnitude in sets having fruit inside the bell jar than sets without it. Very high concentration of proline in cut flowers without fruit may point out protective device against wilting and membrane damage. Many fold increment in proline concentration in sets without fruit compared to initial day level in Chrysanthemum spp. may indicate effective measure to tackle the stress. The degree of increment was relatively smaller in Calendula. Inclusion of fruit has accelerated senescence resulting shorter vase life.