Alternative use of tobacco as a sustainable crop for seed oil, biofuel, and biomass

Abstract

Tobacco, Nicotiana tabacum, is an industrial crop traditionally used for manufacturing cigarettes. However, due to restriction of European subsidies, an alternative use of tobacco is needed, such as biofuel or biomass. Tobacco is indeed an oilseed crop with an oil yield ranging from 30 to 40 % of seed dry weight. Yet, there is still little information on the cultivation of tobacco for seed oil production. Here, we tested tobacco cultivation as an oilseed crop in Central Italy, where flue-cured tobacco is traditionally cultivated, with an additional trial in Northest Italy. We used the cultivar Solaris, selected for its reduced size and elevated number of flowers, and tested its adaptability to different field management practices in 2013–2014. Results show that in Central Italy fields, at the beginning of ripening, tobacco plants showed on the average a 94–105 cm height and a stem diameter between 1.3–1.6 cm; they had 123–151 capsules and each plant produced on average from 31 to 34 g of seeds. Seed production was evaluated to be 1.1–1.8 t/ha, with an oil yield up to 0.59 t/ha. In Northest Italy, two seed harvests determined a total seed yield of 4.5 t/ha, from which 1.48 t oil/ha could be obtained. The cultivar Solaris was extremely adaptable in terms of morphological parameters and seed yield to different management practices as well as climatic conditions. This study shows for the first time the cultivation feasibility in Italy of a small-size tobacco variety selected for high seed production. With a further optimization of the cultivation protocol to increase the oil yield and to use the by-products, tobacco can really become a novel industrial crop providing renewable sources for both biofuel and biomass as well.