Exploring on-farm agro-biodiversity: a study case of vegetable landraces from Puglia region (Italy)

This paper reports the results of a survey carried out in the Foggia province (Puglia Region, Italy) with the aims of: (1) assessing the level of diversity and distribution of the on-farm vegetable landraces, (2) identifying vegetable landrace-rich areas, and (3) analysing the main agro-ecological, socio-economic factors affecting their maintenance. Several territorial surveys were performed over four years and a total of 163 vegetable crop landraces were found at 52 sites, mostly cultivated on small farms or home gardens by elderly farmers. The surveyed landraces belong to nine botanical families and 34 species, with the highest number for Solanaceae, Cucurbitaceae, Brassicaceae, Liliaceae and Leguminosae. The diversity status of the landraces was evaluated by adopting a landscape scale approach considering the provincial landscape types (LT) (3) and, within each LT, the landscape units (LU) accounting for the incidence of high-productive and marginal agricultural systems and of natural/seminatural systems. Principal component analysis clearly separated one landscape unit for each LT for their higher abundance of landraces and higher diversity, richness and evenness of species. These LUs are characterized by high-ecological and agricultural marginal land where the low fertility of soil seems conducive to landraces maintenance. Additionally, the preservation of vegetable diversity may be linked to the distance of the surveyed sites from the most important urban centres along with the commitment of local people and/or tourists to traditional products and their related cultural aspects.