The Effect of Seed Priming with Polyamine Spermine on Key Photosynthetic Parameters in Fusarium culmorum Infected Winter Wheat

Photosynthesis is a primary plant physiological process, which can easily be affected by various environmental factors, including biotic stressors. The exogenous application of different substances like plant growth regulators might benefit this process both under normal and stress conditions. It is well known that the polyamine spermine positively modulates photosynthesis. We evaluated the effects of 5 mM spermine seed priming on photosynthesis-related parameters in wheat (Triticum aestivum L.) plants grown from Fusarium culmorum-infected seeds. Under no stress conditions, the spermine seed priming improved leaf gas exchange, chlorophyll a fluorescence, and leaf pigment content compared to the control. In non-primed seedlings exposed to the pathogen, these parameters were significantly affected. The most substantial reductions were seen in the net photosynthetic rate (56%), transpiration rate (63%), and stomatal conductance (58%). In plants cultivated from seeds primed with spermine the pathogen’s adverse effect on the assessed parameters was mitigated. Our study demonstrates the efficacy of spermine seed priming in sustaining photosynthetic activity in wheat plants exposed to biotic stress induced by Fusarium culmorum.