Nitrogen fixation and growth of annual Medicago?Sinorhizobium associations at low temperature

Annual Medicago (medics) represents a great potential of forage production in areas suffering from shortage of livestock feed; however, low winter temperature delays the growth and reduces the nitrogen fixation of medics in Mediterranean dry areas with cool to cold winter. In this context, the identification of medics able to fix nitrogen and produce dry matter at low temperature is necessary to extend the grazing period.