Starter irrigation in sulla as a promising practice to climate change adaptation of Mediterranean rainfed forage systems

Possible climate change scenarios which are projecting altered rainfall patterns and extreme events have the potential to undermine the regeneration ability of Mediterranean rainfed forage systems. Within these systems Sulla coronaria (sulla), a much appreciated short-lived Mediterranean legume, to-lerates summer drought. Under a rainfed regime, sulla plants regrow due to late summer rain in the year after sowing. The research was performed in Sardinia (Italy) in order to investigate the feasibility of starter irrigation (the land was moistened to restart vegetative regeneration in a timely manner) and to evaluate the productive, environmental and economic implications of cultivating sulla. During a severe autumn drought, the starter-irrigated vs. the rainfed crop were compared. The application of the planned starter irriga-tion assured a prompt plant restart and positively affected the leaf traits and crop performances. In December, leaf length and area reached 42 cm and 90 cm2, twice the level as the rainfed leaves. Forage dry matter and crude protein yields reaching 5.2 and 1 t ha-1 were 9, 8-fold higher. Additionally, seasonal net gains of 120 kg ha-1 of fixed N, 548 kg ha-1 of saved CO2 eq. emissions, and an economic gain of 881 euro ha-1 were recorded. Starter irrigation acted as an effective adaptation strategy to climate change and supplied contextual, productive, environmental and economic benefits.