Influence of Silver Nanoparticles, Laser Light and Electromagnetic Stimulation of Seeds on Germination Rate and Photosynthetic Parameters in Pumpkin (Cucurbita pepo L.) Leaves

The study aimed to determine the impact of laser light (L), magnetic stimulation (p) and silver nanocolloid (AgNC) on pumpkin seeds on the germination rate and content of photosynthetic pigments as well as the efficiency of photosynthesis and greenness index in the plant’s development stages. Seeds germinated after the use of various combinations of different refining techniques. The best results were observed for the alternating magnetic field, where the germination energy increased significantly by 20% relative to the control. A similar effect was observed in terms of germination capacity which increased by 4%. A decrease in terms of emergence rate was observed in all study groups. Leaves grown from seeds soaked in nanocolloidal silver on platters were characterised by a significantly higher content of chlorophyll a and b by, respectively, 53 and 11%, as well as 79% higher carotenoid content. The leaves of potted plants contained 42 and 43% more chlorophyll a in groups p and AgNC. In addition, 66 and 81% more carotenoids in groups L and p. At the stage of the onset of flowering of pumpkin, an improvement in terms of photosynthetic efficiency and greenness index was observed in all study groups. The highest improvement was recorded for seeds soaked in silver and reached 23% (intensity of photosynthesis) and 11% (greenness index SPAD).