Studies on post-harvest attributes of tuberose (Polianthes tuberosa) cultivars as influenced by tinting with edible colours

Tuberose (Polianthes tuberosa) is a popular cut flower having white coloured fragrant blooms. In order to increase the value and appeal of flower along with fragrance, the spikes of tuberose can be tinted with artificial colours. Therefore, three cultivars viz. Shringar, Calcutta Double and Prajwal were selected to carry out tinting and post harvest studies. The freshly harvested cut flower spikes were treated with five edible dyes (Respberry Red, Orange Red, Green, Yellow and Chocolate brown) alone or in combination with 8-HQC to observe the effect of edible dyes on quality and vase life of tuberose. The cut ends of tuberose spikes were immersed in dye solution for six hours and after that they were transferred to distilled water. Minimum weight loss (6.09 g) and percent weight loss (17.71%) was observed in cut spikes of cultivar prajwal, however, maximum weight loss (12.85 g) and percent weight loss (25.04%) was recorded in cv. Calcutta Double. Maximum volume of dye uptake (6.89 ml) was recorded with 0.2% green dye; among cultivars the spikes of cv. Calcutta Double showed maximum dye uptake (5.29 ml). Maximum water uptake (32.80 ml) was recorded in flowers treated with 0.2% yellow dye + 200 ppm 8HQC (T₉). Among three cultivars maximum water uptake (31.46 ml) was recorded in cv. Shringar. Minimum floret drying (26.26%) throughout the studies was observed in flowers treated with 0.2% raspberry red dye+200ppm 8HQC. Among cultivars, Prajwal showed minimum floret wilting (24.63%). The maximum vase life (12.58 days) was observed with 0.2% raspberry red dye while minimum vase life (9.15 days) was observed with orange red dye. The cultivar Calcutta Double flowers exhibited maximum vase life (12.60 days) while cv. Prajwal flowers showed minimum vase life (8.81 days).