Biochemical and Physiological Changes in Artemisia herba-alba Plants under Water Stress Conditions

Abstract: Container experiments were carried out in order to underline the main effects of water stress on physiological and biochemical behaviour of Artemisia herba–alba Asso. After germination, seedlings were well-watered until the age of 4 months when they were subjected to a limiting water supply (70 % and 40 % of container capacity, CC). This first treatment (T1) lasted 36 days and was followed by a re-watering treatment of 40 days period (T2). Several parameters known as indicators of plant status were monitored after drought treatment and subsequent re-watering. It was specially, about biomass production, plant water content, chlorophyll, sugars and proline contents and osmotic potential. Water drought led to a significant decrease of biomass accumulation, water content and chlorophyll content under both 70 % and 40 % CC. However, the intensity of water stress showed a positive correlation with sugars and proline accumulation. Well watered plants showed the higher biomass production but the lowest organic components concentration unlike treated plants which showed the contrary evolution of these parameters. Drought stress, again, had a significant impact on the osmotic potential of plants, thereby it showed a significant decrease (p< 0.05) when irrigation was reduced to 70 % CC or 40 % CC. The stop of stress and the re-watering allowed the progressive return to the initial values and helped in the recovery of plants. Altogether, these data indicate that A.herba–alba has high aptitude permitting adaptation to unkind environmental conditions of the natural habitat