Hamideh Heydari, - Department of Biology, and Center of Excellence in Phylogeny of Living Organisms in Iran, School of Biology College of Science University of Tehran
Vahid Niknam - Department of Biology, and Center of Excellence in Phylogeny of Living Organisms in Iran, School of Biology College of Science University of Tehran
Hassan Ebrahimzadeh - Department of Biology, and Center of Excellence in Phylogeny of Living Organisms in Iran, School of Biology College of Science University of Tehran

Sesame (Sesamum indicum L.) is a drought tolerant plant. However; this species is sensitive to drought at germination and seedling stages. Sesame is one of the oldest and important oilseed crops. It is usually cultivated in arid and semi-arid regions of the world for its highquality edible oil and it is very responsive to the changing environmental conditions. The aim of the present study was to investigate the effect of salt stress on some physiological and biochemical parameters and to assess the possibility of improving salt tolerance of sesame by application of penconazol (PEN). Four weeks after sowing, plants were treated with different concentrations of NaCl (0, 50, 100, and 200) with or without PEN (15 mg l−1). The results showed that salt stress decreased pigments content that this is more abundant in Darab and Naz tak shakheh than Ultan. Under NaCl concentrations, MDA content increased Darab and Naz tak shakheh was superior to Ultan. Under 200 mM NaCl concentrations proline content increased Ultan and Naz tak shakheh but decreased in Darab. PEN treatment with 200 mM NaCl concentration increased pigments content. Darab more than two other cultivars. In addition to PEN application with 200 mM, NaCl concentration increased proline content in Ultan and Darab. Also, PEN application with 200 mM NaCl concentration reduced the MAD content in Ultan and increased in Darab and Naz tak shakheh

Sesame, Salt stress, PEN