Title : Influence of salt stress on morphological and biochemical characteristics of peach (prunus persica l.) nemaguard rootstock in vitro
This investigation was carried out during the period from 2017 to 2018 to study the effect of NaCl on growth of Peach Nemaguard rootstock. MS media supplemented with 1.0 mg /L and 0.1 mg/L IAA caused the maximum shoot number, shoot length (cm) and shoot fresh weight (g) in starting stage. Adding 1.0 mg /L of both BA and KIN to MS media led to the maximum shoot number and shoot fresh weight (g) in multiplication stage. Salt stress induced by adding sodium chloride (NaCl) at 0.0, 15, 30, 60 and 120 mM into the Murashige and Skooge medium was applied for four weeks. NaCl-induced salt stress reduced the morphological characteristics such as shoot number, shoot length, leaves number, shoot fresh weight (g), shoot dry weight (g) and survival percentage in Peach Nemaguard rootstock. Also, NaCl reduced relative water content, chlorophyll a, b, total chlorophyll and carotenoids. Elements accumulation and proline content in plant leaves in relation to salt stress were increased by increasing salt concentration. Results showed that adding NaCl from 30 to 120 mM to MS media caused the reduction in K, Ca and P elements while this led to an increase in Na and Cl elements in leaf Peach Nemaguard rootstock. Results indicated that adding 30 and 60 mM NaCl to MS media attained a severe reduction in stomata density, length, and width of stomata and inside or outside cell guard in comparison with control. Peach Nemaguard rootstock realized maximum salt tolerance up to 3500 ppm of NaCl.