Influence of drought stress on growth and mineral uptake of GF677 (peach and almond hybrid) rootstock under in vitro conditions

The effect of drought stress induced by polyethylene glycol (PEG-6000) on the growth and mineral uptake of GF677 (peach and almond hybrid) rootstock was investigated in vitro using solid and liquid mediums. Plantlets of the GF677 rootstock were subcultured into the Murashige and Skoog (MS) proliferation medium containing 1 mg/l BA (6-Benzyladenine) and 0.1 mg/l NAA (naphthaline acetic acid) under four different drought stress conditions: 0 (control), 1, 2, and 3 percent polyethylene glycol. After six weeks, results indicated that the highest drought level reduced fresh weight, dry weight, shoot length, and proliferation rate, with the reduction being greater in the solid medium than in the liquid medium. Leaf abscission was greater in the solid medium than in the liquid medium. In the liquid medium, the GF677 rootstock absorbed more nitrogen (N) than in the solid medium. Drought stress had no effect on phosphorus (P) uptake. Potassium (K) uptake increased when drought levels were evaluated in both mediums, but was greater in the liquid medium than in the solid medium. Calcium (Ca), magnesium (Mg), and iron (Fe) uptake decreased in both mediums as drought levels increased. The GF677 rootstock was capable of uptake of N and K at a high concentration. Mineral uptake was greater in a liquid medium than in a solid medium. In conclusion, the GF677 rootstock exhibited a high capacity for N and K uptake under drought stress.