The agronomic variability of a collection of sainfoin accessions

Sainfoin (Onobrychis viciifolia Scop.) is a perennial forage legume appreciated for its feed value and rusticity. Two types are characterized via their growth habit and persistence: the common form which does not flower in the sowing year, and the giant form that does. In order to evaluate the degree of belonging to either of these types, thirty-eight Spanish sainfoin accessions and six foreign cultivars (44 accessions) were studied. The study involved three trials of 36 plants per accession in three locations in the northeast of the Iberian Peninsula during 2002-2004. Two locations received no irrigation while one was irrigated. The variables analysed were: percentage flowering in the sowing year, autumn regrowth, stem length at the end of winter, and the capacity for summer regrowth after the first cut. A cluster dendogram showed two large groups encompassing common or giant sainfoins. These could be divided into three subgroups each according to the degree of contamination or crossing between the two major groups. Two easily identified characteristics-percentage flowering in the sowing season, and the speed of regrowth after the spring cut-help in the classification of these plants into one or the other form, and could facilitate cultivar selection.