اثر اسيد ساليسيليك و متيل جازمونات بر بهبود تحمل پسته به خشكي در شرايط درون شيشه اي

چكيده انگليسي :

74 Effects of Salicylic Acid and Methyl Jasmonate on Improvement of Pistachio Tolerance to Drought Stress under in vitro Conditions Hamed Rahmani h rahmani@ag iut ac ir hamed rahmani90@gmail com January 22 2014 Department of Horticulture Isfahan University of Technology Isfahan 84156 83111 IranDegree M Sc Language FarsiCyrus Ghobadi Cyrus@cc iut ac irBahram baninasab bbanin@cc iut ac irAbstractPistachio nut tree is one of the crops which has drought tolerance and traditionally been cultivated indifferent areas of Iran Soil and water salinity water relative deficiency in arid and semi arid areas arelimiting factors which have restricted acreage of pistachio cultivations Reduced rainfall and low wateravailability for agriculture in recent years has led to carrying out research on the use of plant growthregulators to improve drought tolerance in plants The present study was performed to investigate theeffects of salicylic acid and methyl jasmonate at different concentrations each of them at four levels onenhancing drought tolerance in ghazvini pistachio seedlings under in vitro conditions Various levels ofwater stress were induced using five concentrations of agar 8 10 12 14 and 16 gl 1 in MS medium Water potential of different media were 0 77 0 84 0 91 0 98 and 1 05 Mpa respectively The resultsof the study indicated that growth indicies such as number of leaves shoot and root fresh weightsignificantly decreased under different levels of water potential However water stress had no significanteffect on shoot length The maximum number of leaves and fresh weight of shoots were obtained frommethyl jasmonate at 50 M All concentrations of salicylic acid decreased the number of leaves shootand root fresh weight SA had no significant effect on shoot length There was a significant increase inproline content at 1 05 Mpa water potential and the highest rate of proline was related to the use of 0 3mM salicylic acid although no treatments of methyl jasmonate had significant increase in proline content Increasing the water potential of the medium leads to a decrease in chlorophyll a b a b and thecarotenoid Application of 200 M methyl jasmonate led to the highest increase in all chlorophyllcontents The highest amount of carotenoid was achieved using methyl jasmonate at 50 M Alltreatments of salicylic acid reduced chlorophyll pigments and carotenoid Malondialdehyde rate was notaffected by water potentials and methyl jasmonate Salicylic acid was increased leading to an increase inmalondialdehyde The activity of antioxidant enzymes catalase peroxidase and ascorbate peroxidaseincreased with increasing the water potentials The highest catalase activity was related to the use ofmethyl jsmonate at 200 M and salicylic acid at 0 1 mM Using 0 3 mM Salicylic acid caused the highestenzyme activity of peroxidase and ascorbate peroxidase According to the results of this study it could beconcluded that the use of 50 M methyl jasmonate resulted in improving pistachio status under waterpotential stress Also the use of high concentrations of salicylic acid caused pistachio susceptibility todrought stress Keywords Pistachio Water potential Methyl jasmonate Salicylic acid Antioxidantenzymes

رحماني، حامد

اثر اسيد ساليسيليك و متيل جازمونات بر بهبود تحمل پسته به خشكي در شرايط درون شيشه اي

پتانسيل اسمزي , آنزيم هاي آنتي اكسيدان