Abstract

Introduction: Pistachios are among the major horticultural products in Iran. The production of strong seedlings is required to give a high crop yield. Materials and Methods: A hydroponic culture medium was used in this study to control the environmental conditions of cultivation more effectively. For this purpose, pistachio seeds, from Badami Zarand cultivar, were planted in 18 pots, with each pot containing 3 seeds. Two quantities of 5 and 25 mM calcium acetate were added to a modified Hoagland solution in a hydroponic culture medium. Next, 60 ppm of 6-benzylaminopurine was sprayed 3 times per 2 weeks on 9 pots, including 3 replications of treatments. As a result, 6 treatments were produced, including a blank one, calcium 5, calcium 25, 6-benzylaminopurine, 6- benzylaminopurine and calcium 5, as well as 6-benzylaminopurine and calcium 25. After 4 months, the seedlings were harvested, with some growth factors, including stem height, stem diameter, as well as root and shoot dry and wet weight measured. Results: The effects of 6-benzylaminopurine were significant on most of the mentioned growth factors, except seedling height. There were different results concerning the treatments of the 2 amounts of calcium acetate, in which calcium 5 as well as 6-benzylaminopurine and calcium 5 yielded better results. In the end, the best treatment was determined to be 6-benzylaminopurine and calcium 5. Conclusion: According to the results of this study, using calcium at low concentrations is useful for the growth of pistachio seedlings. In addition, using growth regulators improves growth factors, such as root dry and wet weight as well as stem diameter. Applying the findings of this study could be useful in producing stronger plants under stressful conditions.