GA 2017

The ambition to employ natural plant products as efficient and biosafe insecticide agents has encouraged the study of essential oil producing plants. Insecticidal and antimicrobial activities of wild pistachio have been attributed to its essential oils [1] Volatile metabolites of this dioecious tree have been investigated [2]. Seasonal variation and antioxidant activity of Pistacia atlantica leaf essential oils are also reported [3]. Meanwhile, no data exists on the oil secreting structure in this medicinally popular tree, and the relation between its oil production and leaf development has not been elucidated so far. This research aimed to correlate leaf structural and developmental traits with terpenoid pattern in Pistacia atlantica Desf.ssp mutica. Samples were collected from wild growing male and female trees in Fars province, south western Iran. Leaves harvested at three developmental stages, from emergence to maturity, were double fixed with glutaraldehyde and osmium tetroxide, dehydrated in acetone series, coated with gold-palladium and viewed with SEM. Essential oils obtained by hydrodistillaion were analysed by GC-MS. SEM observation revealed four types of glandular trichomes on both leaf surfaces of male and female trees, at all the developmental stages. Young expanding leaves of both male and female trees showed all the trichome types in active secretory phase, and had the highest amount of the essential oil. The oils were rich in monoterpenes hydrocarbons and oxygenated sesquiterpenes. The main components of the leaf essential oils were not significantly different in male and female trees, but their relative percentage was affected by the leaf developmental stage. The total number of essential oil components showed positive and negative correlations with the leaf development in female and male trees, respectively. References: [1] Rouma A, et al J Plant Pathol 2009; 91:339-345 [2] Tzakou O, et al. Flavour Fragr J 2007; 22: 358-362 [3] Gourine N, et al. J Am Oil Chem Soc 2010; 87:157-166.