The effect of biostimulants applied on some cool-season turfgrass on germination and seedling traits and quality

This study was carried out to determine the effect of biostimulants on the germination and plant gowth characteristics of some cool season gass (Lolium perenne, Festuca arundinaceae, Festuca rubra, Poa pratensis). Seaweed (Ascophyllum nodosum) was applied by spraying at doses of 3,3 and 6,6 g/L in a field experiment and at a dose of 1/500 for priming seeds in the laboratory. On the other hand, due to the low germination of P. pratensis, pre-chill (Control-room temperature, +4 °C wet and +4 °C dry) treatments and priming with different plant gowth regulators (Control-Dry, Control-Water, MS, MS+50 mg/L BA, MS+100 mg/L BA, MS+100 mg/L GA3, MS+250 mg/L GA3, MS+500 mg/L GA3) were conducted in the laboratory. It was determined that a 6,6 g/L dose was more effective for NDVI, chlorophyll content, and canopy temperature in field experiments, and P. pratensis species showed a higher response to this dose. In terms of germination percentage, seaweed was either similar to the application with water or caused a negative effect. On the other hand, the seeds with water and seaweed treatments germinated in a shorter time than the control. While seaweed increased shoot length more in F. arundinacea, water application increased in other gass species. In terms of root length, water application in L. perenne and P. pratensis species, and water and seaweed application in F. arundinaceae and F. rubra showed higher and similar results. Seedling fresh weight was found to be higher in untreated seeds and this effect was similar in dry matter ratio. On the other hand, dry matter ratios of control and seaweed applications are higher and similar to water applications. As a result of prechill and seed in P. pratensis, the highest total germination percentage was determined with 81,5% at +4 °C dry prechill and MS+50 mg/L BA application. In this species, the highest emergence percentage was obtained from MS treatment after wet prechilling at +4 °C with 90,5%. In conclusion; 6,6 g/L seaweed application in field conditions affected the development of gass species positively. However; in terms of germination and seedling characteristics of cool-season gasses, seaweed did not indicate the expected effect, and seed with water was more successful. In other germination and emergence experiments on P. pratensis, germination and emergence rates, and seedling development were increased with pre-chilling and seed applications. Keywords: Seaweed (Ascophyllum nodosum) germination, emergence, P. pratensis, GA3, BA