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Contaminated land, that is unsuitable for food production, represents an alternative option for crops producing feedstock for bioproducts and bioenergy, which would otherwise be in competition with food production. It has been estimated that there are more than 10 million major contaminated sites worldwide, while in the European Economic Area (EEA)-39 countries the registered contaminated sites are up to 650000. Even though often perceived solely as a problem, contaminated areas could instead become a real asset that needs to be valued. One of the aims of MAGIC project was to screen the most promising industrial crops for cultivation on contaminated and saline soils. The effects of the heavy metals Cd, Pb, Ni and Zn on fifteen industrial crops were examined, namely on: biomass sorghum, camelina, cardoon, castor bean, crambe, Ethiopian mustard, giant reed, hemp, lupin, miscanthus x giganteus, pennycress, safflower, switchgrass, tall wheatgrass, and wild sugarcane (African fodder cane). The experiments were conducted following the same methodology and protocols by all partners involved.

Uncertainty in predictions of long-term yields of perennial grasses makes business plans untenable in the short run. Long-term data across varied environments, including marginal lands, will help in preventing uncertainty while providing farmers and entrepreneurs with sound information to estimate reliable and affordable strategies on what, where, and how long to grow perennial grasses. In the present study, the long-term yields (11 to 22years) of switchgrass (Panicum virgatum L.), miscanthus (Miscanthus × giganteus Greef et Deuter), and giant reed (Arundo donax L.) grown in northern and southern Mediterranean environments are reported. Switchgrass was grown in Greece and northern Italy, giant reed in southern and northern Italy, and miscanthus in southern Italy. Furthermore, lowland and upland switchgrass ecotypes were compared in Greece. Despite similar biomass productions (9.8 and 10.0Mg DM ha−1 for uplands and lowlands, respectively), the upland ecotypes showed a significantly higher yield stability (CV of 24 and 32% for uplands and lowlands, respectively) over a 17-year period. Biomass yield varied considerably across years and locations; giant reed outperformed switchgrass under northern Italy environment (21.2 and 13.6Mg DM ha−1 for giant reed and switchgrass, respectively). Annual yield of switchgrass was 30% higher in the north than south Mediterranean; miscanthus showed intermediate production compared to giant reed and switchgrass (average of 22years) and a CV similar to switchgrass. In summary, these results evidence that multi-location, long-term trials are strongly needed to reduce uncertainties on crop yield variability and provide more accurate data from which optimized socio-economic and environmental predictions can be achieved.

Research is needed to look for plants or lines that can thrive on soils affected by water deficit or other constraints. The present work investigated the potentiality of Saccharum spontaneum L. spp. aegyptiacum (Willd.) Hack., a lignocellulosic, perennial, rhizomatous, no-food crop in semi-arid Mediterranean area. A 3-year field trial was carried out with the aim to evaluate its physiology, biomass yield, water use efficiency, and biomass quality under different soil water availability. During 2011/2012, 2012/2013, and 2013/2014 growing seasons (hereinafter referred as 2011, 2012, and 2013, respectively), three levels of maximum evapotranspiration restitution (ETm) were compared: I 100 (100% ETm restitution), I 50 (50% ETm restitution), and I 0 (rainfed condition). Net photosynthesis, stomatal conductance, and transpiration rate were strictly related to the available soil water content (ASWC), with maximum gas exchange at field capacity. However, gas exchange between plants and atmosphere was also measured when ASWC was close to wilting point. Biomass dry matter (DM) yield and main morpho-biometric traits (e.g., stem height and basal stem diameter) were significantly affected by ASWC. A non-linear model showed that maximum DM yield, 37.86 Mg ha −1 , can be achieved when 1150 mm of water were used by the crop. Water use efficiency (WUE) was always highest in rainfed condition ( I 0 ), however, only in 2013 I 0 was significantly higher than I 50 and I 100 (5.89 g L −1 vs 4.26 and 3.33 g L −1 ). Within the variables employed, a linear model showed that WUE was negatively related to crop water use (CWU). The fiber content was not affected by the irrigation treatments. In the average, hemicellulose, cellulose, and lignin accounted for 23.9 (% w/w), 35.0 (% w/w), and 19.9 (% w/w), respectively. On the other hand, moisture and ash content, bulk density, low heating value, and ash melting point resulted significantly affected by the treatment. Present results suggested that S. spontaneum spp. aegyptiacum possesses a range of agronomically desirable traits of biomass crop: C4 plant, high biomass yield, active assimilation rates during drought–stress periods, able to use water efficiently, and satisfactory biomass quality.

Side by side biomass productivities, harvesting time (autumn vs. winter) and frequency (annual vs. biennial) of three perennial grasses were compared under northern and southern Mediterranean climates. Miscanthus ( Miscanthus × giganteus Greef et Deu.) was compared to giant reed ( Arundo donax L.) in Catania (37°24′N, 15°03′E), and to switchgrass ( Panicum virgatum L.) in Bologna (44°55'N, 11°45′E). Generally, giant reed produced about 50% higher biomass than miscanthus in Catania. Miscanthus almost halved biomass productivity in the driest year, while giant reed reduced biomass yield by only 30% under the same conditions. In Bologna, miscanthus and switchgrass produced similar amounts of cumulative biomass over 6 years. Switchgrass kept more stable annual yields than miscanthus, which, however, evidenced a higher potential under favorable climate conditions. Autumn harvest significantly reduced biomass productivity and quality (moisture content, ashes, cellulose and hemicellulose), particularly under South Mediterranean climate. In Catania, autumn biomass was 50% (giant reed) to 85% (miscanthus) lower than winter biomass, while in Bologna, autumn cut reduced switchgrass yield by 20%. Biennial harvesting resulted in almost 40% lower cumulative biomass yield than annual cut, after 6 years.

In the frame of OPTIMA project (Optimization of Perennial Grasses for Biomass production, 289642) four perennial grass species (Saccharum spontaneum spp. aegyptiacum, Sorghum halepense, Oryzopsis miliacea and Cimbopogon hirtus) were established at the Experimental Field of Catania University (Catania plain, 10 m a.s.l., 37°27'N, 15°03'E) in spring 2010 in a Mediterranean environment. Gas exchange measurements, using a gas exchange chamber (LICOR 6400 system, LI-COR Bioscience), have been carried out in the dry season between spring and summer 2012, therefore before the water stress (May), during water stress (June-July) and severe water stress (August), respectively, while productive measurements in winter 2011 and 2012. A long term plantation of giant reed managed in the same condition and grown in the same experimental field has been used as reference crop. Giant reed has been chosen as the reference crop since something is already known about this species regarding physiological traits in south Mediterranean environments. During the measurement time (May, June, July and August) the air temperature, relative humidity, intercepted PAR and soil moisture at 0-30, 30-60 and 60-90 cm were recorded. Cymbopogon and Oryzopsis behaved differently respect to giant reed, even though a decrease in net photosynthesis was observed from May to August. Before the water stress those two species reached 10 µmol CO2 m­ 2 -1-2 -1 s , while only 5 µmol CO2 m s during the severe water stress condition. Saccharum and Sorghum showed, instead, the same trend of the reference crop during the measurement time. Saccharum reached the highest value -2 -1 before the water stress (24-26 µmol CO2 m s ), while it was about two unit value lower than both Sorghum and -2 -1 giant reed during severe water stress (16 vs 14.5 µmol CO2 m s ). It is worth to mention that during the measurement of July and August the leaf temperature was close to 41 °C. Saccharum was the significantly highest yielding species both at the first and second year (9.8 and 18 t DM ha-1, respectively), while Sorghum, Cymbopogon and Oryzopsis were all not significantly different both at first and second year harvest (2.7 and 5.5 for Sorghum, 2.6 and 4.0 for Cymbopogon, 3.5 and 3.6 t DM ha-1 for Oryzopsis). These results show that there are significant differences among the wild perennial grasses both in terms of physiological and productive characters. Water and severe water stress lead to a reduced gas exchange of water transpired to the CO2 uptaken. Further studies need to be carried out to understand physiological mechanism of these new species., Proceedings of the 21st European Biomass Conference and Exhibition, 3-7 June 2013, Copenhagen, Denmark, pp. 326-329

Perennial grasses considered as ideal feedstock for biobased products and bioenergy production. During the last two decades several grasses have been tested at european level in the framework of research projects. According to 4FCROPS project the most importnat perennial crops for Europe are: miscanthus, reed canary grasses, switchgrass, giant reed and cardoon. Two of them (reed canary grass and miscanthus) cultivated in a commercial scale with a total area of cultivation 29500 ha. Miscanthus and giant reed established by using rhizomes or plantlets, while all the other established by seed. Their lifetime is 15 years, while for cardoon it is reporting that its rotation cycle last 4 to 5 years. In 4FCROPS the yields of these crops as well as the raw material characteristics based on the findings of the main research projects that have been carried out in Europe the last two decades. Addionally, the economic viability of these crops were investigated though the developing of several economic case studies for specific sites in EU27 when the crops cultivated in both agricultural and marginal lands as well as with low an high inputs. In the same project the environmental impact analysis of the five selected perennial crops with annual energy crops and conventional crops potato showed that the perennial crops had lower impact compared to the annual ones and the conventional crops. Currently, the perennial grasses are being investigated in three research projects entitled: OPTIMA, OPTIMISC GRASSMARGIN and EUROBIOREF., Proceedings of the 20th European Biomass Conference and Exhibition, 18-22 June 2012, Milan, Italy, pp. 201-206

The influence of transplanting time of Arundo donax L. in relation to vegetative clone plant propagation systems was studied for two subsequent growing seasons (2008-2011) at the Experimental farm of Catania University (Italy). A factorial experiment was carried out combining three times of transplanting (November 5th 2008, March 17th 2009, April 30th 2009), two clone propagation methods (rhizome cuttings and stem cuttings) at two soil water availability (irrigation only at the transplanting dates and irrigation from transplanting dates to end of summer). At each transplanting dates 23 mm of water were applied; in the irrigated treatment, from May to end of August, other 250.0 mm of water were applied. The time span between planting to emergence of the first stems has been 168 days (first planting dates), 41 days and 24 days for second and third planting dates respectively. Stem cuttings have shown a good plant establishment in the first and second planting dates; furthermore in all planting dates showed a positive effect on planting density due to supplementary irrigation whereas rhizomes did not. On the contrary rhizomes have a good establishment in the second and third planting dates. Generally speaking the second planting dates was the best for all propagation methods., Proceedings of the 20th European Biomass Conference and Exhibition, 18-22 June 2012, Milan, Italy, pp. 527-530

As different sectors – food, feed, fiber, and fuels – compete for land, the yielding potential of the future non­food crops has to be as efficient as possible in order to minimize the competition for land. The main objective of 4F CROPS project was to survey and analyze all the parameters that play an important role in successful non­food cropping systems in the agriculture of EU27 alongside the existing food crop systems. The work started with the prediction of the future land use in short term (2020) and long term (2030), taking under consideration restrict factors for agriculture and the market were determined. This group of non­food crops was subjected to a comparative cost analysis with conventional crops for the same time framework. Socio­economic impacts, like farmers’ income, rural development, public development, and public acceptance were analyzed. Then environmental implications were assessed compared to their respective conventional products (fossil energy, conversional materials). Several environmental impacts were assessed like soil quality and soil erosion, air quality and climate change, water issues, biodiversity and landscape by using LCA and EIE methods. The regulatory framework of the non­food crops were considered including existing policies, co­existence and safety measures when the crops used for both food and non­food crops. The collected information was used for the formation of scenarios for the successful non­food cropping alongside food cropping systems answering whether a completive bioeconomy is a viable option for EU27., Proceedings of the 19th European Biomass Conference and Exhibition, 6-10 June 2011, Berlin, Germany, pp. 253-259

The influence of transplanting time of Arundo donax L. in relation to vegetative clone plant propagation systems was studied in 2009 at the Experimental farm of Catania University (Italy). A factorial experiment was carried out combining three times of transplanting (November 5th 2008, March 17th 2009, April 30th 2009), three clone propagation methods (rhizome cuttings, horizontal stem cuttings and vertical stem cuttings ) at two soil water availability (irrigation only at the planting dates and irrigation from planting dates to end of summer). At each planting dates 23 mm of water were applied; in the irrigated treatment, from May to end of August, other 250.0 mm of water were applied. The time span between planting to emergence of the first stems has been 172.8 days (first planting dates), 50.3 days and 40.1 days for second and third planting dates respectively. Horizontal stem cuttings produced the significantly highest stem density (4.2 stem m-2); horizontal stems have shown, in all planting dates, a positive effect on planting density due to supplementary irrigation whereas rhizomes and vertical stems did not. Generally speaking the second planting dates was the best for all propagation methods. Horizontal stems have shown a good plant establishment in the first and second planting dates; on the contrary rhizomes in the second and third while vertical stems have shown the worst establishment rate., Proceedings of the 18th European Biomass Conference and Exhibition, 3-7 May 2010, Lyon, France, pp. 522-525

The stem cuttings of giant reed crop with a certain number of dormant viable buds are suitable to produce new plants (by growth of node shoots and development of adventitious roots); preliminary studies show that the uses of stem cuttings is less expensive than rhizome cuttings. However in the semi-arid Mediterranean environment the soil water content can be a limiting factor. Bearing this is mind, an experimental research was carried out in spring-summer 2009, in the Catania plain (Southern Italy) to compare sprouting rate of giant reed cuttings from basal (BS), median (MS), apical (AS) area and a mix (XS) of them, in two soil water conditions: Irrigated (100% ETm restoration from transplant to end of dry summer season, 267.5 mm); Rainfed (irrigation only at the planting date, 17.5 mm ). The results indicate that the number of sprouted nodes at the end of August were 0.7 nodes m-2 (11.53% of the buried nodes), without any difference between part of the stems while in percentage of buried nodes, significantly higher in BS portion (17.88%) than in AS portion (6.27%). The sprouted nodes were significantly higher in the well watered condition (0.95 viable nodes m-2) than in rainfed ones (0.45 viable nodes m-2); equally stem density at the end of the number of stems per square meter emission was significantly affected by soil water conditions (1.63 and 4.28 stems m-2 in rainfed and irrigated condition respectively). Moreover the research allowed to point out that the minimum water requirement for stem sprouting was 25% of the available soil water content., Proceedings of the 18th European Biomass Conference and Exhibition, 3-7 May 2010, Lyon, France, pp. 518-521