Abstract
Drought is an important abiotic stress that limits the plant growth and productivity. A pot experiment was conducted by using complete randomized design (CRD) with three replications (each replication contained three plants) to evaluate morphological and physiological attributes that can be used for characterization of drought tolerance in 2 varieties of Marigold (Super Giant & Inca F1). Four drought levels at 100% (control), 80%, 70% and 60% field capacity were maintained throughout the experiment. Morphological characteristics including plant height, number of leaves/plant, leaf firing percentage, leaf area, plant quality, root length, shoot fresh and dry weight, root fresh and dry weight and root-shoot ratio for fresh and dry weights were studied. Physiological parameters studied, were net CO2 assimilation rate (Pn), transpiration rate (E), stomatal conductance (gs), sub-stomatal conductance, leaf water potential, water use efficiency Pn/E and chlorophyll content. Results showed that, overall plant quality of varieties decreased with the progression of drought stress where 70% F.C can be considered appropriate for acceptable plant quality, whereas Inca F1 performed better compared to Super Giant for all attributes studied.