ECOLOGICAL ADAPTABILITY AND ESSENTIAL OIL QUALITY OF MATRICARIA CHAMOMILLA L. UNDER CLIMATE CHANGE CONDITIONS

Аннотация

This study investigated the ecological adaptability and essential oil quality of Matricaria chamomilla L. (German chamomile) under varying climate stress conditions in Uzbekistan's arid and semi-arid regions. Field experiments were conducted across three ecological zones (Tashkent, Samarkand, and Karakalpakstan regions) from 2022-2024, exposing chamomile populations to controlled drought stress, elevated temperature regimes, and varying irrigation schedules. Essential oil extraction was performed using hydrodistillation, followed by GC-MS analysis to determine compositional changes. Results revealed significant adaptability variations among populations, with Samarkand accessions demonstrating superior drought tolerance (survival rate: 78.4% vs 45.2% in control). Water availability emerged as the most critical environmental factor affecting essential oil content, with moderate water stress (50% field capacity) paradoxically increasing oil yield by 23.7% compared to optimal irrigation. Essential oil composition showed notable shifts under stress conditions, with α-bisabolol content increasing from 34.2% to 42.8% under moderate drought stress, while chamazulene concentrations remained stable (8.3-9.1%). Temperature stress above 38°C significantly reduced total oil yield by 31.2% but enhanced the therapeutic value through increased sesquiterpene alcohol content. These findings demonstrate M. chamomilla's remarkable phenotypic plasticity and suggest optimal cultivation strategies for maintaining essential oil quality under projected climatescenarios inCentral Asia. Keywords: Matricaria chamomilla, climate change adaptability, essential oil composition, drought stress, Central Asia, arid zonecultivation,GC-MS analysis