GIS-Facilitated Germination of Stored Seeds from Four Wild-Growing Populations of Petromarula pinnata (L.) A. DC.—A Valuable, yet Vulnerable Local Endemic Plant of Crete (Greece)

Abstract

The ex situ conservation and sustainable exploitation of neglected or underutilized plant species (NUPs) is an urgent and vital endeavor. To this end, we focused on Petromarula pinnata (Campanulaceae), a vulnerable local plant endemic to Crete (Greece) that has been garnering interest for its agro-alimentary, medicinal, and ornamental value. A GIS ecological profile was established herein based on the natural distribution of this species in Crete. This profile contains detailed information on the climatic conditions (minimum, maximum, and mean temperatures; precipitation), as well as information on 19 bioclimatic variables that shape its natural adaptations. This profiling contributed to a better understanding of the species’ ecological requirements and facilitated germination trials employing stored seeds from four distinct populations (two from lowlands and two from semi-mountainous areas) at four temperatures (10, 15, 20, and 25 °C) and two light conditions. The results presented here show that both incubation temperature and population of origin, as well as the interaction between these variables, significantly affected seed germination rates. Incubation temperatures of 10 and 15 °C were the most appropriate for the successful germination of this species (>81.25% for both temperatures in three out of four populations), with light conditions having no effect on seed germination (86% in light and 80% in darkness). The establishment of a protocol for the successful germination of P. pinnata seeds opens avenues for further sustainable exploitation of this valuable yet vulnerable NUP as a new Greek native crop.