A comparative study of oilseed crops (Brassica napus L. subsp. oleifera and Brassica carinata A. Braun) in the biodiesel production chain and their adaptability to different Italian areas

The Extravalore project aims to give added value to oilseed crops, considering them also for producingmultiple products with the same economic value and being interesting for the market thanks to theirvarious utilizations.An evaluation of the main cultivars of Brassica napus subsp. oleifera and Brassica carinata has beenperformed within the project, analyzing them in three Italian locations with different climatic condi-tions (Palazzolo dello Stella - North Italy, Osimo - Central Italy, Cassibile - South Italy) to assay theiradaptability and production potential.During the 2010-2013 period, 43 varieties of rapeseed were evaluated, but only 13 of them for all theperiod considered; moreover, also 4 varieties of B. carinata were tested.The seed yields of tested cultivars of rapeseed varied a lot among locations, depending also by theseasonal trend. Central Italy was the less disadvantaged by climatic conditions: on average, it was reacheda seed yield of 4 t ha-1, a theoretical oil production of 1.63 t ha-1and more than 8 t ha-1of crop residues.In Northern and Southern Italy, if compared with Central Italy values, the seed yields were both lowerthan 30% and theoretical oil productions lower than 60%; moreover, crop residues in Northern Italy were12% lower than in Central Italy while in Southern Italy 65% lower. The agronomic behavior of varietiesdiffered a lot among the three experimental areas: DK Expower was the best at North; Albatros, Artoga,Exagone and Excalibur in Central Italy; Excalibur, Zoom and PR46W14 at South Italy but none of themreached a seed yield of 2 t ha-1.Concerning B. carinata, the cultivars did not give good productions in any of the experimental areas,mainly because of the low oil content in the seeds. Even in Central Italy, where the best results wereregistered, the seed yield was on average 28% lower than in rapeseed and oil production 10% lower; thecrop residues were double than rapeseed. In any case, the valorization of the crop residues is importantwith a wide range of possible utilization from the direct energetic use to the biochemicals extractionwith consequent environmental advantages due to the substitution of dedicated or fossil feedstock with crop residues.