Impact of quarries emissions on the leaf morpho-anatomy of three olive (Olea europea L) cultivars grown in Palestine

Abstract

To investigate the effects of quarries emissions on the leaf morpho-anatomy of Romi, Nabali and K18 olive cultivars in Taffouh village (Palestine), one set of olive cultivars of two-years old was cultivated close to quarries while the control set was cultivated almost 4 km from quarries. The morphology of six month-old leaves was examined. Leaf segments were fixed in compound fixative of formaldehyde, acetic acid and 70% ethanol (FAA). The segments were then embedded in Paraplast plus and 5 m thick sections were stained with safranin and fast green. A reduction in trichome density was evident for the three cultivars in response to exposure to quarries emission, with high density in the abaxial epidermis. Moreover, the abaxial epidermis of the three cultivars possessed elaborated and well-developed trichomes. The leaves of Romi cultivar exhibit increase in all leaf components except the adaxial epidermis while Nabali cultivar exhibited a reduction in all leaf components. Nevertheless, K18 cultivar exhibited a reduction only in palisade and spongy layers due to exposure to quarries pollutions. In conclusion, quarries emissions led to condensed palisade and spongy cells in all cultivars. In addition, Romi cultivar showed a variegated increase in all morpho-anatomical parameters concomitant with increased sclerophylly of leaves following their exposure to quarries emissions. This cultivar proved to be the most resistant to quarries stress which implies it is well suited for olive production.   Key words: Adaptation, leaf anatomy, Olea europea, olive, quarries stress, trichome.