Rehabilitation with annual pasture mixtures in different Mediterranean regions.

There is a general need of setting up new plant mixtures to rehabilitate degraded lands and to improve pasture productivity in the Mediterranean rainfed areas. The use of legume mixtures under sub-optimal and variable environmental conditions, like many agro-pastoral regions, could be essential to achieve persistent and high quality pasture swards. Because of their cool-season growth habit, high adaptation to summer drought through the ability to regenerate dense populations from year to year, and plasticity of response to seasonal fluctuations due to the buffering function of the seed reserves in the soil, the annual self-regenerating legumes are extraordinarily suited to Mediterranean-type climates (Piano and Talamucci, 1996). The use of annual legume mixtures, including new species and varieties recently released, could improve pasture quality and persistence. Moreover the lengthening of the grazing season seems more effective when different species of annual self-reseeding legumes such as subterranean clover and burr medic are combined in mixtures (Pardini et al., 1996).