PHYSIOLOGICAL AND DEVELOPMENTAL RESPONSES OF 'TRAKYA ILKEREN' GRAPEVINES TO SEAWEED (Ascophyllum nodosum L.) EXTRACT PULVERIZATIONS UNDER CONTINENTAL CLIMATE CONDITION

Multiple environmental stressors pressurized the agriculturists to implement much more fertilizers, pesticides and waters for higher production. Such an intensified agriculture technique threatens the natural sources and exacerbates the adverse effects of climate change on agriculture. Therefore, this study was performed to investigate the effects of different concentrations (0.0, 0.1, 0.3, 0.5, 1.0 and 2.0%) of foliar seaweed extract, a natural plant biostimulator, pulverizations on grapevine (Vitis vinifera L. cv. Trakya ilkeren) physiology and development under the multiple stressors of continental climate condition. A total of nine homogenously grown plants in three replication per treatment was used. As the seaweed substance, 100% water soluble extract of Ascophyllum nodosum L. (0.1% N, 4% K2O, plant hormones, vitamins and enzymes) was used. Seaweed treatments were performed three times with one month interval, beginning from the early vegetative development stage. Among the doses, 0.3% and 0.5% providing similar results, were the most effective applications in improving the leaf stomatal conductance (gs), although higher seaweed doses were also beneficial for several parameters. The seaweed applied at 0.3% dose the greatest effects on the leaf chlorophyll concentration, leaf area, shoot length and shoot diameter. Therefore, application of the 0.3% seaweed on grapevine leaf would be recommended as eco-friendly sustainable practice for a precision viticulture under the effects of environmental adversities. Keywords: Viticulture, plant stressors, precision agriculture, plant biostimulants