Production of cultivars and native populations of Trifolium subterraneum L. in the south of France (Corsica)

Abstract

On the northern Mediterranean island of Corsica, 28 populations of subterranean clover were tested during 3 years: 18 French native ecotypes, and 5 Australian and 5 Spanish cultivars. A principal component analysis showed that dry matter yields, seasonal growth rhythms, and maturity date were the most important factors in the observed variability. By cluster analysis, 6 groups of subterranean clover were defined from these factors. Seasonal and total yields were linked to annual rainfall, but with a specific coefficient for each group. For 100 mm of rainfall, we obtained a range of production from 0.4 t DM/ha for the least productive group to 1.1 t DM/ha for the highest yielding group. The Australian cultivar, Clare, and 9 native Corsican ecotypes were the most productive genotypes (up to 10 t DM/ha.year in a wet year, with 2 t DM/ha during the winter period). These highest yielding ecotypes could be exploited to breed new mid-to- late-maturing cultivars better adapted to northern Mediterranean environments. In the short term, Clare may be used on large scale, for establishment of improved pastures in this region.