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Mediterranean climates are characterized by long periods of drought during summer and short dry periods from autumn to spring, what limits plant CO2 assimilation and biomass production to a great extent. The JRC has set a series of thresholds to define marginal lands in terms of biophysical constraints. We focus on climate limitation given by the ratio between precipitations and potential evapotranspiration (P/ET). Areas with P/ET ≤0.60 are classified as affected by “dryness”. The present study follows up a long-term plantation of the C4 perennial grass Saccharum spontaneum ssp. aegypticum under different water regimes in a semi-arid Mediterranean environment.

Mediterranean climates are characterized by long periods of drought during summer and short dry periods from autumn to spring, what limits plant CO2 assimilation and biomass production to a great extent. The JRC has set a series of thresholds to define marginal lands in terms of biophysical constraints. We focus on climate limitation given by the ratio between precipitations and potential evapotranspiration (P/ET). Areas with P/ET ≤0.60 are classified as affected by “dryness”. The present study follows up a long-term plantation of the C4 perennial grass Saccharum spontaneum ssp. aegypticum under different water regimes in a semi-arid Mediterranean environment.

Perennial, no-food grasses have been proposed as the most efficient species for biomass production due to their natural resource use efficiency, agronomic, environmental and social benefits. Nitrogen requirement is a significant issue in intensive agriculture and greatly affects the energetic balance of crops. Hence, reduced nitrogen fertilizer by means of low input cropping systems could directly mitigate greenhouse gas emissions. In the present study long-term plantations of two perennial grasses (Arundo donax and Miscanthus x giganteus) grown in rainfed conditions under two nitrogen regimes were compared in terms of biomass yield and nitrogen use efficiency.

Perennial, no-food grasses have been proposed as the most efficient species for biomass production due to their natural resource use efficiency, agronomic, environmental and social benefits. Nitrogen requirement is a significant issue in intensive agriculture and greatly affects the energetic balance of crops. Hence, reduced nitrogen fertilizer by means of low input cropping systems could directly mitigate greenhouse gas emissions. In the present study long-term plantations of two perennial grasses (Arundo donax and Miscanthus x giganteus) grown in rainfed conditions under two nitrogen regimes were compared in terms of biomass yield and nitrogen use efficiency.

Within a framework of renewed interest in crambe (Crambe abyssinica Hochst ex R.E. Fries) sourcing raw materials for the bio-based industry, the adaptability and productive performances of this oil crop have been evaluated under contrasting Mediterranean environments (i.e., a fertile site in the northern part of Po valley vs. a semi-arid site of southern Sicily) during two consecutive growing seasons, aiming at its possible stable introduction in this area. The trial set in northern Italy compared three commercial varieties of crambe (Galactica, Nebula and Mario) in spring sowing, while in southern Italy only the var. Mario was tested with autumn sowing. Regardless of location and variety, thermal time for maturity was quite stable (1200–1400°C), and the crop provided satisfactory seed yields (grand mean 2.29Mghulledseedsha−1), with average oil content of ∼400gkg−1 (on dehulled seeds) and ∼52% of erucic acid. Significantly higher seed and oil yields were reached in northern than in southern Italy. Furthermore, crambe thermal use efficiency (THUE) was also higher in the north than in the south, possibly due to better environmental adaptability of the crop. The limited intraspecific variability within crambe was confirmed, with better productive performances showed by the domestic selection Mario. Promising traits were revealed in Nebula, showing greater seed weight, root length density and area, and thinner roots, although the root growth of crambe was generally modest compared with modern high erucic acid rapeseed hybrids. Available crambe varieties could be efficiently included in crop rotations across a wide range of environments within the Mediterranean basin. The short growth cycle represents an outstanding added value for this species, allowing the avoidance of prolonged drought and heat stress typical of late spring/early summer months under the Mediterranean climate. However, increased yields are needed to meet the market requests; nonetheless, the little genetic variability suggests that there is large scope for future breeding improvements, maybe exploiting advanced techniques to improve the existing genetic resources.