Studies on the Role of Phytohormones as Senescence Retardants

Photosynthesis is the most important Physico-chemical process on which plant growth and development depend. Various intrinsic factors such as aging (senescence) and extrinsic factors like several abiotic stress conditions influence the photosynthetic process. Hence in this investigation, an attempt has been made to study the effect of phytohormones on senescence by incubating the primary leaves of 8th-day old maize plants for different intervals (24-72h) in dark in the presence and absence of phytohormones (Aux/ GA/ CK at the concentration of 25M). Due to its agronomical and economical importance, maize has been chosen as an experimental system. After incubation in the presence and absence of phytohormones, leaves have been sampled and thylakoid membranes have been isolated and proceeded to measure the phytochemical activities using polarographic, spectroscopic analysis and electrophoretic studies. our results clearly demonstrated that CK is delaying senescence than that of others.