Genetic zones of Neltuma flexuosa, the algarrobo tree from the Monte desert in Argentina

The advance of the agricultural frontier and deforestation are leading to the loss of native forests in the Monte desert (Argentina). Recently, revegetation with native material has emerged as an option to reverse landscape deterioration. Neltuma flexuosa is a valid and valuable alternative due to its ecological and economic characteristics. To propose a good sourcing strategy and guidelines for the appropriate use of this species, we studied neutral (NGV) and adaptive (AGV) genetic variation. We evaluated eight microsatellite molecular markers and measured the quantitative variation for height and basal diameter in individuals from eight provenances (40 families) growing in a common garden. Based on neutral genetic variability, differentiation, and structure, and considering morphological variation, we propose considering at least three genetic zones in the Monte ecoregion: northern (including Fiambala, Pipanaco, Chilecito and Mogna populations), central (including Niacunian and Lavalle populations) and southern (including Alvear and Aguila Limay populations). To recover most of the NGV and AGV for seed banking purposes, at least three populations are recommended. According to AMOVA, special care should be taken in the sampling of material due to the important genetic variation that occurs among families within provenances. The comparison between morphological and neutral differentiation helps unveil the evolutionary forces that shape the morphological variation suggesting that both height and diameter would respond, in the long term, to the different environmental conditions, resulting in different optima at each site. Alternative sampling strategies for delineating future particular restoration plans are discussed, considering both neutral and adaptive genetic variation results. Fil: Bessega, Cecilia Fabiana. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Ecología, Genética y Evolución de Buenos Aires. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Ecología, Genética y Evolución de Buenos Aires; Argentina Fil: Cony, Mariano Anibal. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mendoza. Instituto Argentino de Investigaciones de las Zonas Áridas. Provincia de Mendoza. Instituto Argentino de Investigaciones de las Zonas Áridas. Universidad Nacional de Cuyo. Instituto Argentino de Investigaciones de las Zonas Áridas; Argentina