EXOGENOUS APPLICATION OF SALICYLIC ACID AT DIFFERENT PLANT GROWTH STAGES IMPROVES PHYSIOLOGICAL PROCESSES IN MARIGOLD (Tagetes erecta L.)

Abstract

Marigold (Tagetes erecta L.) is a famous flowering plant in the world which has medicinal and industrial values. In Pakistan, it is an important floricultural crop and used widely as bedding plant. Pakistan is facing water shortage, which is affecting crops growth and productivity including marigold badly. Drought stress reduces plant growth, physiological and biochemical processes and flower yield in marigold. Salicylic acid (SA) is a phytohormone and its exogenous application is an effective approach to support plant during drought stress and mitigate its harmful impacts. Present study was planned to evaluate the effect of exogenous salicylic acid application on growth response and drought tolerance potential of marigold. For this purpose, a pot experiment was conducted in rain out shelter with four treatments of SA i.e., no SA application, SA foliar @ 100 mg L-1 application at vegetative growth, reproductive growth and at vegetative plus reproductive growth stages, under normal irrigation as well as under drought stress conditions were imposed. Drought stress was applied by skipping every alternate irrigation. The results showed that SA application at reproductive growth stage of marigold improved plant growth by improving its physiological processes during drought stress. It was concluded that exogenous application of SA, not only increased bioproductivity of marigold plants but also ameliorated the negative impacts of drought stress by enhancing drought tolerance potential in plants.