GIS-Facilitated Seed Germination, Fertilization Effects on Growth, Nutrient and Phenol Contents and Antioxidant Potential in Three Local Endemic Plants of Crete (Greece) with Economic Interest: Implications for Conservation and Sustainable Exploitation

This multidisciplinary study is focused on the conservation and sustainable utilization of <i>Lomelosia minoana</i> (Dipsacaceae; subsp. <i>minoana</i> and subsp. <i>asterusica</i>) and <i>Eryngium ternatum</i> (Apiaceae), three local endemic plants of Crete (Greece) with economic interest. Using Geographical Information Systems and open-source geodatabases, detailed ecological profiles were compiled to illustrate the abiotic environmental conditions prevailing in their wild habitats. We examined for the first time temperature effects (10, 15, 20 and 25 °C) on seed germination and fertilization effects (INM, integrated nutrient management, and chemical fertilization compared to control) on growth parameters and nutrient content of leaves as well as their phenol content and antioxidant potential. <i>L. minoana</i> subsp. <i>asterusica</i> germinated better at 15 °C (61.25%), subsp. <i>minoana</i> at 10 and 15 °C (30% and 27.50%, respectively) while <i>E. ternatum</i> did not show significant differences. The seedling fertilization with INM resulted in 10–15-fold higher absorption of copper without toxicity compared with chemical fertilization and the control; INM was also superior to chemical fertilization in most of the macronutrients in leaves. The total phenol content and the antioxidant capacity of leaf extracts were positively affected by chemical fertilization in <i>L. minoana</i> subsp. <i>minoana</i> and <i>E. ternatum</i>. Both fertilization treatments almost equally affected the morphological and physiological characteristics of the examined taxa. In light of the above-mentioned and the research gaps bridged for the studied taxa, we re-evaluated and updated both the feasibility and the readiness timescale for their sustainable exploitation in economic sectors.