Abstract: A field experiment was conducted in Mediterranean conditions to evaluate the effects of different irrigation volumes and water quality on yield performance of tomato crop. The tomato crop was irrigated reestablishing 50 (I1), 75 (I2) and 100% (I3) of the crop evapotranspiration (ETc) with two water quality: fresh water with EC 0.9 dS m-1 (FW) and saline water with EC 6 dSm-1 (SW). At harvest, total and marketable yield, weight, number, total soluble solids (TSS) and dry matter of fruit were calculated, The results showed no statistical differences among the three different irrigation volumes on tomato yield and quality. The salinity treatment did not affect yield, probably because the soil salinity in the root zone on average remained below the threshold of tomato salt tolerance. Instead, salinity improved fruit quality parameters as dry matter and TSS by 13 and 8%, respectively. After the first field application of saline water, soil saturated extract cations (SSEC), electrical conductivity of soil paste extract (ECe), sodium absorption ratio (SAR) and exchangeable sodium percentage (ESP) cations increased; the largest increase of cations, in particular of Na, occurred in the top layer. At the end of the experiment, the absolute value of SSEC, ECe and SAR, for all the effects studied, were lower than those recorded in 2007. This behavior was suitable to the reduced volumes of treatments administered in 2009 in respect to the 2007. Furthermore, the higher total rainfall recorded in 2009 increased the leaching and downward movement of salts out of the sampling depth.

Abstract: In this study at regional scale, the model DSSAT was applied in order to simulate the cultivation of winter durum wheat and tomato to estimate the green water and the blue water through a dual-step approach (with and without supplemental irrigation). The model simulation covered a period of 30 years in three scenario including a reference period and two future scenarios based on forecasted global average temperature increase of 2 and 5°C. In this paper GW e BW contribution for evapotranspiration requirement is presented and analyzed on a distributed scale related to Puglia region (Southern Italy) characterized by high evaporative demand of the atmosphere. For winter durum wheat the GW component was predominant compared to BW, covering almost 90% of the ETc of WW. Under Baseline scenario the weight of BW was of 11%, slightly increasing in the future scenarios. After considering the probability the climate change determine an increase of irrigation practice for WW from climatic point of view we carried out an example of analysis in order to verify the economical convenience of supplemental irrigation for WW cultivation. The probability that irrigation has a negative or zero income ranged between 55 and 60% and the climate change did not impact the profitability of irrigation for WW as simulated for the economic and agro-pedoclimatic conditions of Puglia region considered in this study.For tomato, in the baseline and future scenarios affected by global warming, the analysis of ET components showed with strong evidence the importance of irrigation that is confirmed as irreplaceable practice for obtaining sustainable yield from productive and economical point of view.GW and BW, both in the case of wheat and tomato, appeared dependent on the spatial and temporal distribution of rainfall during the crop cycle, but also on the hydraulic characteristics of soils corresponding to each calculation unit. No Label