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Quantitative performance as well as product quality traits among a group of durum wheat cultivars developed and selected in different eras from 1915 to 2003 were examined in an south Italian growing region under organic management. Experiments were conducted over four years. Fertilization treatments included the application of 80 kg organic nitrogen (N) fertilizer and fertilization by only the N residue from leguminous pre-crop. Genetic, agronomic and environmental effects for the investigated traits and significant interactions between factors were found. Application of organic N fertilizer increased grain yield and protein concentration, the mean increase compared to the treatment without applied fertilizer was 14.8% and 12.0%, respectively. Moreover, a significant improvement of gluten quality was observed for higher N availability. Significant cultivar by treatment interactions were observed for all quality traits. Cultivars significantly differed in grain yield and semolina protein content; mean values ranged from 2.54 to 3.50 t/ha and from 10.83 to 11.91% d.m., respectively. Modern cultivars showed the highest values. Although, significant cultivar by environment interactions were detected for agronomic and quality traits, cultivars with a stable high performance in regard to grain yield and semolina protein could have been identified. These results evidenced different adaptability of “old” and “modern” cultivars to organic production and identified only one of the “modern” cultivars as suitable to use organic nutrients in order to achieve high grain yield and quality.

In this study elevated temperature effects on protein quality parameters and in particular on protein sulfhydryl-disulfide contents were assessed. Four Italian durum wheat cultivars which differed for the qualitative trait changes produced by heat stress were employed. During grain filling two different thermal regimes were imposed on the plants grown in a typical area of durum wheat cultivation (Southern Italy). Results confirmed significant effects of high temperatures on the quality of products in the durum wheat chain and indicated that elevated temperatures determined changes on protein redox status, particularly evident on S-S bond content. For most of the examined traits significant cultivar x treatment interactions were also evidenced.

During the 1996/97 season twenty durum wheat cultivars were grown in Foggia, a typical area of durum wheat cultivation in Italy, in order to assess the varietal response to the effects of heat stress on characteristics affecting grain and milling quality. In the field trial high temperature stress was imposed during grain filling by covering the plots from ten days after anthesis until ripeness with PVC film tunnels, obtaining maximum temperatures about 10°C higher in the tunnels than in the open. Results evidenced that, in general, the percentage of gluten, total and insoluble proteins increased with high temperature whereas a reduction was observed for kernel and specific weight. Considerable differences among the varieties examined in the response to heat stress were observed pointing out different sensitivity levels to this environmental factor. Therefore, on the basis of the changes of insoluble protein percentage, important qualitative parameter of durum wheat, the varieties were arranged in tolerant and sensitive groups and, in relation to grain qualitative characteristics, the different performance of the two groups was also evidenced.

Plastic is probably the fraction of the waste of electrical and electronic equipment (WEEE) most challenging to manage and the market of recycled plastics from WEEE is limited to few cases. In this study, twenty WEEE plastic samples collected in two material recovery facilities (MRFs) from manually sorted housings and components and among some discarded devices stored in Casaccia Research Center were analysed through infrared identification and chemical-physical characterization. The analyses were carried out in order to select the suitable samples for mechanical recycling in 3D printer filaments. Eleven different polymers or blends were found in the WEEE samples and the majority of those collected in the MRFs resulted as mixtures of different plastics, although often of styrene-based nature. On the other hand, many WEEE samples showed a good similarity to the corresponding virgin polymers with a content of halogens and inorganic fillers less than 0.2 and 5 wt%, respectively. The thirteen selected WEEE plastic samples were washed, reduced to < 4 mm and extruded in filaments with the proper diameter. The polymeric heterogeneity and the presence of foreign materials in some samples were the main critical issues highlighted during the extrusion. The suitable filaments were used to print test objects with different geometries. The quality control of the scanned objects, through a structured-light 3D scanner, showed that specimens printed with WEEE plastic filaments had no significant higher deviation from the model design in comparison to the same object produced using the commercial filaments.