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[en] The topic of energy crops, namely of those crops designed to produce biomass to transform into ethanol, has been explored, in Italy and abroad, in all its technical and agronomical aspects. The microeconomic aspect, including the evaluation of convenience for the farmer in adopting such crops, is, on the contrary, less well researched. RENAGRI has developed a research methodology able to give information about the level of convenience of two energy crops (Sweet Sorghum and Topinambour) and has applied it to different Italian agricultural situations, in order to verify the existence of conditions favourable to the cultivation of the two crops, or to indicate the necessity of eventual subvention. (author)
[en] Highlights: • A model to simulate field drying of sorghum was developed, calibrated and validated. • Late sorghum variety had the highest dry matter production at harvest. • Duration and dynamics of field drying were affected by variety earliness. • Early variety had the highest probability to be baled at suitable moisture content. • Early variety had the shorted drying period and permanence in the field. - Abstract: A major constraint to the use of biomass sorghum varieties (Sorghum bicolor (L.) Moench) to generate electricity by direct combustion is the high biomass moisture content at harvest that, under unfavourable weather conditions during field drying limits the possibility to achieve a suitable moisture content for baling. In this work, the CropSyst model was calibrated and validated with data collected in experimental trials conducted in the Po Valley (northern Italy). It was then used to simulate biomass production of three sorghum varieties of contrasting earliness (early, medium-late, and late). In order to simulate the dynamics of biomass moisture content during field drying, a specific model, “sorghum haying model”, was developed and validated. The two models combined were used to simulate, for three sorghum varieties of contrasting earliness (early, medium-late and late), biomass production and the probability to achieve during field drying a biomass moisture content suitable for baling. In a long term simulation (140 years), the late sorghum variety achieved the highest dry biomass production (16.5 Mg ha−1) followed by the medium-late (15.4 Mg ha−1) and early (15.1 Mg ha−1) variety. The early variety had the highest probability (0.66) of being baled at a moisture content ≤ 18%, followed by the medium-late (0.53) and late (0.37) varieties. The early variety, also having the shortest average field drying (9.2 days), was considered the most suitable for the selected environmental conditions.
[en] The fluxes of incident solar radiation, reflected and net radiation were measured during the growing cicle of two fields of sweet sorghum (Sorghum bicolor L.), cus. BR-501 and BR-503, maintained under convenient irrigation level. Resultant data allowed to estimate the crop albedo as well as the estimates of Rn. (M.A.C.)
[pt]Estudam-se, durante o ciclo de desenvolvimento de duas variedades de sorgo sacarino (Sorghum bicolor L.), BR-501 e BR-503, os fluxos de radiacao solar global incidente, refletida e do balanco de radiacao total, radiacao liquida, em uma area irrigada. Estimam-se o albedo das culturas bem como equacoes de Rn. (M.A.C.)
[en] Several protocols of plant regeneration via somatic embryogenesis from Sorghum bicolor (L.) Moench have been development, however the percentage of calluses with embryogenic structures and plant regeneration are low. Therefore this study aimed to generate somatic embryos in red sorghum variety CIAP 132-R. Different concentrations of 2,4-D for callus formation, and three concentrations of ascorbic acid to remove phenolics exudation were assayed by explant. For the formation of embryos different concentrations of 2,4-D and 6-BAP were evaluated. The highest percentage of callus formation (57.5 %) was achieved with 18.1 μM 2,4-D. With the addition to the culture medium of 50.0 mg.l-1 of ascorbic acid was possible to eliminate the phenolic compounds in the explant and in the culture medium; also it allows increasing the percentage of calluses with embryogenic structures up to 95 %. The highest number of somatic embryos per callus was achieved with a reduction in the culture medium of 2,4-D to 4.52 μM in combination with 2.22 μM 6-BAP. For the first time, the efficiency of somatic embryo formation was obtained from the freshly germinated sprouts of immature seeds as initial explant CIAP 132-R.
[en] We have earlier reported the effects of chemically synthesized copper nanoparticles (CuNPs) on oxalate oxidase (OxOx) activity, extracted from the shoot tissue of germinating grain sorghum i.e. in vitro. Here, we tried to study this effect in vivo and compare it with those of Cu2+. We describe herein, characterization of CuNPs and their effects on oxalate oxidation system i.e. OxOx activity, total oxalate and H2O2 content in vivo i.e. in shoot tissues/leaves of germinating grain Sorghum (Sorghum vulgare L). To achieve it, grain sorghum seeds were grown up to 10 days in laboratory, irrigated with Hoagland's solution containing either CuNPs (1.0 ppm) or Cu2+ (1.0 ppm) after 4 days of germination. Control were irrigated with Hoagland solution only. The shoot/leaves of the seedling plants were harvested at 4, 6, 8 and 10 day of germination and analysed quantitatively for OxOx activity, soluble protein, H2O2 and total oxalate. The growth of the Sorghum seedling plants supplemented with CuNPs and Cu2+ was decreased significantly (P <0.1) at all growth stages compared to control. This inhibitory effect of CuNPs was higher than Cu2+. CuNPs decreased the activity of OxOx but Cu2+ had no effect at day 10. Both CuNPs and Cu2+ decreased the specific activity of OxOx and H2O2 content but increased total oxalate content at day 10. The decrease in H2O2 content in both CuNPs and Cu2+ supplemented shoot tissues with concomitant increase in oxalate content confirmed the decreased activity of OxOx in CuNPs and Cu2+ supplemented seedling plants. (author)