Screening and evaluation of thermo- and photoinsensitive lines for off-season production of chrysanthemum

Abstract

In the curre nt scenario of climate change it is very necessary to identify heat tolerant chrysanthemum (Denranthema × grandiflora Tzvelev.) cultivars for commercial production in hot areas of the world. In this study screening has been done from the chrysanthemum germplasm available at the Directorate of Floricultural Research (DFR) which are suitable for summer flowering when mean temperature during vegetative stage is (23.17°C) and during flowering stage is (35.10°C). The duration of bright sunshine hours is 5.62 h and 4.20 h during vegetative and flowering stages, respectively. Vegetative characteristics such as plant height, plant spread, number of side branches, and flowering characteristics such as number of buds per branch, number of buds per plant, flower size, flowering duration were recorded. Among the different cultivars 'DFRC-128', 'DFRC-25', 'DFRC-87', 'S-33/533', 'Mother Teresa', 'Royal Prince', 'Cinderella Yellow', 'Vanity Pink', 'Khoshoo' have appropriate cut stem length for standard cut flower production and 'DFRC-123', 'DFRC-128', 'Royal Prince', 'DFRC-125', 'Mother Teresa', 'Kaul', 'Khoshoo', 'Autumn Joy' are suitable for cut spray production during the summer season. Maximum flower size was observed in cultivars 'Moria', 'Red Devil', 'Autumn Joy' (7.34 cm). A maximum flowering duration of 11 days was recorded for 'Autumn Joy'.