Performance and Stress Tolerance of Poppy (Papaver somniferum L.) in Response to Biostimulant Treatments

The goal of the study was to identify the effects of fulvic acid (FULV) and methyl jasmonate (MEJA) in increasing the yield, alkaloid content and drought-resistance of poppy (Papaver somniferum L.). The trials were carried out in both field and controlled conditions; in the latter, with two water supply regimes (50 and 75% soil water capacity). The treatments were applied by exogenous foliar spraying. In the field experiment, we observed a 22.4% increase in yield (capsules with seeds) under of FULV and a 44.2% increase due to MEJA. The treatments could not intensify the concentration of alkaloids. Under controlled conditions, MEJA decreased total biomass but capsule yield was not lower, its proportion even increased. Antioxidant capacity (AC) and total phenolic content (TPC) increased (11 and 22%, respectively) together with proline concentration (by 134%) under dry conditions. In addition, biostimulant sprayings stimulated the AC (by 6.6% MEJA and by 11.5% FULV). FULV was effective also in graising the TPC (by 14.5%) and producing a 417% rise in the concentration of soluble sugars. Our results may contribute to the protection of poppy under drought as well as to a more detailed understanding of its stress responses.