Effects of Plant Essences on Physiological Characteristics of Two Cultivars of Iranian Commercial Pistachio Nuts

To study the effects of thyme, savory, mint, and eucalyptus essences on photosynthetic efficiency, chlorophyll fluorescence, changes of transpiration, and leaf temperature of two cultivars of pistachios, namely, abbasali and shahpasand, a research was done in one of the commercial gardens of damghan in 2012. this experiment was implemented in split, split plot as complete randomized block design, by two essences in five levels (4 experimental essences and one control sample). cultivar type was evaluated at two levels and three replications and effects of treatments on physiological properties of the samples were studied. type of essence regarding variance analysis table indicates significant effect on the rate of photosynthesis as %1. also, effects of cultivars, cultivars × essence, concentration of essence, cultivars × concentration of essence, type of essence × concentration of essence and interaction of type and concentration, were not significant. thyme essence had more pronounced effects on photosynthesis measure than other essences and was at higher rank with average of 12.22 μmolm^-2s^-1.