Study of Growth, Mineral Uptake and Photosynthesis of GF677 (Peach and Almond Hybrid) Rootstock in Response to Iron Source under In Vitro Conditions

Influence of organic iron (Fe-EDTA) and inorganic iron (FeCl3) on growth, mineral uptake and photosynthesis parameters of GF677 (Prunus persica × Prunus amygdalus) rootstock were studied under in vitro conditions. Plantlets of GF677 rootstock were subcultured to modified Murashige and Skoog (MS) medium containing 1 mg l-1 6Benzyladenine (BA) and 0.1 mg l-1 naphthaline acetic acid (NAA) 0, 0.05, 0.1 and 0.2 mM concentrations of Fe-EDTA and FeCl3. The experiment was containing on a completely randomized design with five replicates in eight weeks. Results showed that, treatments of 0.1 and 0.2 mM Fe-EDTA and 0.2 FeCl3 had a significant effect on measured parameters. The highest fresh weight, dry weight, proliferation rate, shoot length, leaf chlorophyll index, photosynthesis rate and stomatal conductance of plantlets were observed in 0.2 mM FeEDTA, Meanwhile, control (iron free) and 0.05 mM FeCl3 treatment had the, highest leaf chlorosis and lowest growth rate, leaf chlorophyll index, photosynthesis rate and stomatal conductance. Both iron sources caused increasing Fe uptake by plantlets, but 0.1 and 0.2 mM Fe-EDTA had a significant effect on Fe uptake in comparison to FeCl3. Treatment of FeCl3 decreased P, Zn and Mn uptake by plantlets. Increasing Fe-EDTA concentration in the medium increased Mn uptake and decreased P and Zn uptake. So, according these results, replacing Fe-EDTA instead of FeCl3 in in vitro culture of GF677 rootstock, improve growth response and photosynthesis parameters.