Unity in diversity—food plants and fungi of Sakartvelo (Republic of Georgia), Caucasus

Abstract Background The Republic of Georgia is part of the Caucasus biodiversity hotspot, and human agricultural plant use dates back at least 6000 years. Over the last years, lots of ethnobotanical research on the area has been published. In this paper, we analyze the use of food plants in the 80% of Georgia not occupied by Russian forces. We hypothesized that (1) given the long tradition of plant use, and the isolation under Soviet rule, plant use both based on home gardens and wild harvesting would be more pronounced in Georgia than in the wider region, (2) food plant use knowledge would be widely and equally spread in most of Georgia, (3) there would still be incidence of knowledge loss despite wide plant use, especially in climatically favored agricultural regions in Western and Eastern Georgia. Methods From 2013 to 2019, we interviewed over 380 participants in all regions of Georgia not occupied by Russian forces and recorded over 19,800 mentions of food plants. All interviews were carried out in the participants’ homes and gardens by native speakers of Georgian and its dialects (Imeretian, Rachian, Lechkhumian, Tush, Khevsurian, Psavian, Kakhetian), other Kartvelian languages (Megrelian, Svan) and minority languages (Ossetian, Ude, Azeri, Armenian, Greek). Results The regional division was based primarily on historic provinces of Georgia, which often coincides with the current administrative borders. The total number of taxa, mostly identified to species, including their varieties, was 527. Taxonomically, the difference between two food plant groups—garden versus wild—was strongly pronounced even at family level. The richness of plant families was 65 versus 97 families in garden versus wild plants, respectively, and the difference was highly significant. Other diversity indices also unequivocally pointed to considerably more diverse family composition of wild collected versus garden plants as the differences between all the tested diversity indices appeared to be highly significant. The wide use of leaves for herb pies and lactofermented is of particular interest. Some of the ingredients are toxic in larger quantities, and the participants pointed out that careful preparation was needed. The authors explicitly decided to not give any recipes, given that many of the species are widespread, and compound composition—and with it possible toxic effects—might vary across the distribution range, so that a preparation method that sufficiently reduces toxicity in the Caucasus might not necessary be applicable in other areas. Conclusions Relationships among the regions in the case of wild food plants show a different and clearer pattern. Adjacent regions cluster together (Kvemo Zemo Racha, and Zemo Imereti; Samegrelo, Guria, Adjara, Lechkhumi and Kvemo and Zemo Svaneti; Meskheti, Javakheti, Kvemo Kartli; Mtianeti, Kakheti, Khevsureti, Tusheti. Like in the case of the garden food plants, species diversity of wild food plants mentioned varied strongly. Climate severity and traditions of the use of wild food plants might play role in this variation. Overall food plant knowledge is widely spread all-across Georgia, and broadly maintained.