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

Abstract

This multidisciplinary study is focused on the conservation and sustainable utilization of Lomelosia minoana (Dipsacaceae; subsp. minoana and subsp. asterusica) and Eryngium ternatum (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. L. minoana subsp. asterusica germinated better at 15 °C (61.25%), subsp. minoana at 10 and 15 °C (30% and 27.50%, respectively) while E. ternatum 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 L. minoana subsp. minoana and E. ternatum. 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.

GIS-Facilitated Germination of Stored Seeds from Five Wild-Growing Populations of Campanula pelviformis Lam. and Fertilization Effects on Growth, Nutrients, Phenol Content and Antioxidant Potential

“…asterusica (Greuter) Greuter & Burdet, and Eryngium ternatum Poir. were affected in the same direction regarding these physiological characteristics from the application of fertilization regimes [43]. More specifically, the INF treatment that resulted in this study in increased root dry biomass in C. pelviformis in a similar pattern to the observations related with M. aschersonii, while L. minoana subsp.…”

“…Measurements conducted on the leaves of other local endemic plants of Crete revealed that L. minoana subsp. minoana benefited from the INF application in terms of all macronutrients examined except for Na [43]. E. ternatum showed benefits in terms of N and K, while L. minoana subsp.…”

“…Similar results have been recently reported for another chasmophytic local endemic plants of Crete, namely Campanula saxatilis L. subsp. saxatilis [43]. Previous studies have indicated that various taxa of the genus Campanula can germinate even at 25 • C under specific pretreatment methods [32], i.e., 99% for Campanula merxmuelleri Phitos, 91% for Campanula pangea Hatvig, and 80% for C. glomerata.…”

“…We employed the Folin-Ciocalteu method [43] for the determination of total phenol content (TPC) in samples. Each sample (0.5 mL) was diluted in MeOH (1:50 v/v) with the addition of 2.5 mL of the Folin-Ciocalteu solution (1:10 v/v).…”

“…We employed the 2,2-diphenyl-1-picrylhydrazyl (DPPH) method [43] for the determination of antioxidant capacity (AC). In 0.2 mL of samples dissolved in 80% v/v MeOH (1:20 v/v), the amount of 2.8 mL 4% w/v DPPH was added, vortexed and incubated in darkness for 30 min at room temperature.…”