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Sunflower is a major oil seed crop worldwide, and it is also an important crop in Mediterranean areas where salinity is an increasing problem. In this paper, the effect of saline irrigation water on seed yield and quality of sunflower was evaluated. A pot experiment was carried out over two crop seasons on two hybridsa standard one (Carlos) and a high oleic one (Tenor) -submitted to five salinity levels of irrigation water (0.6, 3, 6, 9 and 12 dS m 21 ). Soil salinity was monitored over the entire crop cycle, and leaf ion content was determined at maturity. Tenor showed higher Na + and Mg 2+ content but lower K + values. No difference between the two hybrids was observed for Cl 2 content. A progressive increase in leaf Na + , K + and Cl 2 contents and Na + /K + ratio with increasing salinity level was observed. Seed weight per head, 1000 achene weight, number of seeds per plant and oil yield significantly decreased under salt stress in both hybrids. The percent seed yield decrease was higher per unit increase in electrical conductivity of irrigation water, ECw (8%), than per unit increase in electrical conductivity of saturated-soil extracts, ECe (5%). Concerning oil fatty acid composition, the main significant difference as result of salt stress was a progressive increase in oleic acid content, from 82.2% to 86.7% for Tenor and from 21.8% to 27.3% for Carlos, which was consistent with a decrease in linoleic acid content, from 5.9% to 3% for Tenor and from 66% to 61.3% for Carlos. These results confirm the possible inhibition of oleate desaturase under salt stress.

Durum wheat (Triticum durum Desf.) is widely cultivated in the Mediterranean area where plants generally suff er from water stress during grain-fi lling period. Th is study was conducted to evaluate the infl uence of N levels and water regimes on N translocation and nitrogen use effi ciency for protein (NUEP) in durum wheat grown under Mediterranean conditions. A 2-yr experiment was performed in southern Italy using four cultivars, two water regimes (irrigated and rainfed) and three N levels (0, 60, and 120 kg ha -1 ). Among the cultivars under study, Simeto showed the highest N translocation in both years and, together with Ofanto, also the highest NUEP values, especially in rainfed condition. Th is highlights their good adaptability to dry southern Italy environment. Nitrogen fertilization caused a general decrease of NUEP and its components in both growing seasons; this was more evident in the fi rst drier year, mainly due to a decrease in N uptake. Under water stress the higher N level caused a decrease in N translocation, N translocation effi ciency, and grain N content. Th e contribution of translocated N to grain N content was 75% in the wetter year and 57% in the drier year, showing that in drought condition preanthesis N assimilation was lower. In conclusion under water stress condition the higher N level (120 kg ha -1 ), despite determining an increase in plant N content, did not imply an increase in grain N content, due to a decrease in N translocation and effi ciency.

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.