Characterisation of germoplasm of annual medics (Medicago polymorpha L.) in the "Bairro Ribatejo" region

This work corresponds to the first stage of a project whose aim is the further selection of cultivars of annual medics for the limestone massif of Central Portugal, and it reports on the characterisation and preliminary evaluation of 45 populations of annual medics (Medicago polymorph L.) collected in the “Região Agrária do Ribatejo e Oeste”. Thirty six traits, decided after the descriptors for annual medics of the International Board for Plant Genetic Resources (IBPGR), were observed throughout the vegetative and reproductive stages. Data were analysed by means of the NTSYS-pe (Numerical Taxonomy and Multivariate System) Program. Traits that showed greater variation were peduncle hairiness, left surface hairiness at mean flowering leaf area one month after transplantation, seed yield per plant, single pod weight and basal internode length. Relatively long life cycles (140 to 181 days from sowing to flowering) were observed in all populations. Forage and see yield were high in most populations. Hard-seededness, evaluated in the months of August, September and October following seed ripening, was always very high, though it decreased with time