راسة التأثير الأليلوبداثي للمستخلص المائي لنبات الشيح Artemisia herba-alba على إنبات ونمو بادرات نبات البطيخ الأحمر Citrullus lanatus L

Abstract

Allelopathy is a major ecological interaction mediated by secondary metabolites released by plants, which can either stimulate or inhibit the growth of neighboring species depending on their concentration. Artemisia herba-alba, a perennial species widely distributed in arid and semi-arid ecosystems of North Africa, is rich in allelopathic chemical compounds such as phenolics and terpenoids. Although numerous reports document its allelopathic effects on cereals and woody plants, its influence on cucurbit crops remains poorly understood. This study aimed to evaluate the allelopathic potential of aqueous extracts from the aerial parts of A. herba-alba on the germination and seedling growth of watermelon (Citrulluslanatus L.). Four extract concentrations (0%, 10%, 20%, and 30%) were prepared according to standard protocols and applied in a completely randomized design with three replicates. Parameters assessed included germination percentage, water uptake, root and shoot length, and dry biomass under controlled laboratory conditions. Results indicated a clear, concentration-dependent response consistent with a stimulatory model: lower concentrations (10% and 20%) significantly enhanced water absorption, root and shoot elongation, and seedling biomass compared to the control, while the highest concentration (30%) reduced germination (70% versus 100% in the control) and inhibited seedling growth. Overall, our findings demonstrate that aqueous extracts of A. herba-alba exert dual allelopathic effects on watermelon, with stimulatory responses at lower doses and inhibitory effects at higher doses. These results provide a scientific basis for exploring the potential use of Artemisia extracts in sustainable crop management, highlighting the need for further phytochemical analyses to identify the active allelochemicals and optimize application strategies under field conditions.