Relationships between Nitrogen Utilization and Grain Technological Quality in Durum Wheat: II. Grain Yield and Qualities

Abstract

Th e relationships between grain quality and N utilization in durum wheat (Triticum durum Desf.) have not been very thoroughly investigated. Th e aim of this study was to evaluate the eff ects of N fertilizer rate and water regime on grain yield and quality under Mediterranean conditions in relation to N utilization. Four durum wheat cultivars (Appio, Creso, Ofanto, and Simeto) were grown in fi eld trials under two water regimes (irrigated and rainfed) at three N levels (0, 60, and 120 kg ha -1 ) in southern Italy during two cropping seasons. At harvest, grain yield and its main components, protein and gluten content, gluten index, sodium dodecyl sulfate sedimentation test, rheological indices dough strength alveograph index (W) and tenacity/extensibility ratio (P/L), and grain yellow index were determined. For the rainfed treatment in the fi rst (drier) year, a decrease in grain yield consistent with an increase in protein content, gluten index, and W and P/L indices was observed. With increasing N level, protein content increased in both growing seasons but a signifi cant improvement in technological parameters was observed only in the fi rst year, mainly under rainfed conditions. Among the investigated cultivars, only Simeto always showed both good yield and quality performance. Th e positive correlation between plant N content at anthesis and protein content indicated a signifi cant contribution of pre-anthesis assimilation. Th e high correlations found for both N translocation and N harvest index with technological indices suggest that lately remobilized N might increase the protein polymerization degree, with a consequent improvement in grain quality.

Agronomic, nutritional and nutraceutical aspects of durum wheat (Triticum durum Desf.) cultivars under low input agricultural management

“…The observed protein levels were in line with those previously reported for old and modern durum wheat varieties cropped under low N input management (Quaranta et al, 2010;De Vita et al, 2007b) and were also comparable with those obtained at higher nitrogen rates by Giuliani et al (2011). The protein accumulation was shown to be highly dependent on genotype, soil fertility (available N) and environmental conditions (temperature, water) (Giuliani et al, 2011;Dupont et al, 2006). In our study, the growing season was observed to have a big effect on protein content, with a significant increase from 143.5 to 161.4 g/kg during the second year compared to the previous one.…”

“…All the varieties studied presented protein amounts that were higher than the minimum industry standard set at 125 g/kg (De Vita et al, 2007a). The observed protein levels were in line with those previously reported for old and modern durum wheat varieties cropped under low N input management (Quaranta et al, 2010;De Vita et al, 2007b) and were also comparable with those obtained at higher nitrogen rates by Giuliani et al (2011). The protein accumulation was shown to be highly dependent on genotype, soil fertility (available N) and environmental conditions (temperature, water) (Giuliani et al, 2011;Dupont et al, 2006).…”

“…strength, tenacity, extensibility). However, the technological quality is only guaranteed when these genotypes are cropped under high nitrogen supply (conventional agriculture) ( Giuliani et al, 2011). In our study, the highest gluten content was obtained for the old variety Senatore Cappelli (120.1 g/kg), while some modern cultivars, such as Anco Marzio, Orobel and Solex, presented very low gluten levels: within 84.8-96.9 g/kg (Table 3).…”

Agronomic traits and deoxynivalenol contamination of two tetraploid wheat species (Triticum turgidum spp. durum, Triticum turgidum spp. turanicum) grown strictly under low input conditions

“…The observed protein content was in line with the values reported by Stagnari et al (2013), but it was lower with respect to our previous study which involved old and modern durum wheat varieties grown under low-input agricultural management (Dinelli et al, 2013). The main factors affecting protein accumulation are N availability and soil organic matter as well as climatic conditions (Giuliani et al, 2011) and their effects, which are particularly significant under organic and biodynamic management, which excludes the use of fertilizers throughout the crop cycle.…”

Cultivar and N Fertilizer Rate Affect Yield and N use Efficiency in Irrigated Durum Wheat

“…Previous research on wheat response to N fertilizer has focused mainly on bread wheat, and limited information is available regarding the effects of cultivar and N fertilizer rate on durum wheat NUE (López-Bellido et al, 2008;Giuliani et al, 2011b). Previous research on wheat response to N fertilizer has focused mainly on bread wheat, and limited information is available regarding the effects of cultivar and N fertilizer rate on durum wheat NUE (López-Bellido et al, 2008;Giuliani et al, 2011b).…”