α-Tocopherol Protection Against Drought-Induced Damage In Rosmarinus Officinalis L. And Melissa Officinalis L.

摘要: Summer diurnal variations of photosynthesis and α-tocopherol content were measured in relation to natural drought field-grown rosemary (Rosmarinus officinalis L.) lemon balm (Melissa plants. During the summer relative water contents (RWC) ca. 40% Rosmarinus 30% Melissa attained, indicating severe drought. Both species showed similar patterns net CO₂ assimilation rates (A) with a wide plateau maximum at midday absence one peak early morning under conditions. Net decreased by 75% due both species. plants significant decrease quantum efficiency PSII photochemistry (ΦPSII), ratio variable fluorescence yield (Fᵥ/Fₘ) chlorophyll leaves 25% conditions midday. In contrast, ΦPSII, Fᵥ/Fₘ remained constant throughout experiment R. Although non-photochemical quenching increased from 1.8 3 a-tocopherol rose fifteen fold response drought, only able avoid oxidative damage joint increase carotenoids