EVALUATION OF HERBICIDE POTENTIAL OF SESQUITERPENE LACTONE AND FLAVONOID: IMPACT ON GERMINATION, SEEDLING GROWTH INDICES AND ROOT LENGTH IN ARABIDOPSIS THALIANA

Abstract

Plants produce a vast array of natural products that mediate their interaction with the environment. Artemisinin is important sesquiterpene lactones, mostly isolated from the Artemisia annua plant, has a wide range of biological activities, including insecticidal, antibacterial and antifungal, antifeedants, and allelopathic properties. Flavonoids (rutin) have attracted attention, primarily as natural antioxidants, and many are allelopathic agents, commonly present in Fagopyrum esculentum Moench. In the present study, phytotoxic effect of artemisinin and rutin on germination and seedling growth of Arabidopsis thaliana were tested under controlled bioassays. Total germination % age was reduced in A. thaliana after treatment with artemisinin at 10, 20, 40, 80, 160 µM concentration; while maximum reduction in germination %age was observed at highest concentrations of 160 and 80 µM. Rutin at 100, 250, 500, 750 and 1000 μM concentration decreased germination % age in A. thaliana but the concentration 1000 μM proved to be most deleterious. Artemisinin at 10, 50, 40, 80, 160 μM concentration inhibited the speed of germination (S) of A. thaliana. Similarly, Rutin-delayed the A. thaliana “S” at all the concentration tested and maximum inhibition was recorded at 1000 μM concentration. The effect of artemisinin and rutin on radicle length (RL) of A. thaliana was concentration dependent. There was a gradual decrease in RL of A. thaliana due to rutin at all concentration. Seedling vigour index (SVI) of A. thaliana was decreased after treatment with both artemisinin and rutin at all concentration while the maximum reduction was observed at highest concentration tested.