In the context of water restriction, the adoption of innovative technology and water saving strategies is crucial to sustainable agriculture production. Thus, we sought to emphasize the contribution of precision irrigation based on Internet of Things (IoT) technology and smart sensors for optimizing irrigation water use. The effects of different drip irrigation regimes on total dry matter (TDM), grain yield (GY) and water use efficiency (WUE) of winter wheat grown on clay-loam soil under semi-arid conditions of Tunisia have been assessed for three consecutive growing seasons. The trial included fully irrigated (FI) treatment (100% of crop evapotranspiration (ETc)), two deficit irrigation treatments (DI1, DI2 corresponding to 75 and 60% of ETc, respectively) and rainfed treatment DI3, replicated three each. The results showed that TDM and GY increase with increasing irrigation amount. At harvest, the highest TDM and GY values were recorded under FI and DI1. Reducing irrigation amount by 40% (DI2) resulted in a significant grain yield reduction, quantified as 52.7, 45.7, 30.4%, respectively, for the three cropping seasons. Across all growing seasons and treatments, WUE_TDM values ranged between 4.11 and 6.32 Kg m⁻³. The highest values were achieved under rainfed treatment. However, no significant difference was observed between irrigated treatments, in particular, during 2022–2023 and 2023–2024. In terms of WUE_GY, no significant difference was observed between the FI and DI1 treatments, while significant reductions were registered under DI2 and DI3. The adoption of deficit irrigation at 75% ETc based on smart tensiometers can be used as an effective strategy to optimize water use in winter wheat without compromising yield.

In Tunisia, water used for irrigation is often saline, increasing the risk of salinization for soils and crops. In this study, an experiment was conducted on a tomato crop cultivated on a silty-clay soil irrigated with three different water qualities: 0, 3.5, and 7 dS·m⁻¹. Experimental data were then used to calibrate and validate the Hydrus-1D model, which simulates water flow and salt transfer in soils. The successfully-calibrated and validated model was then used to study the combined effects of the soil osmotic and soil matrix potentials on root water uptake. The values of the root mean square error (RMSE), the coefficient of determination (CD), the modeling efficiency (EF), and the coefficient of residual mass (CRM) were close to their optimal values for both soil water content and soil electrical conductivity profiles, indicating the reliability of the model to reproduce water and salt dynamics. Relative yields (Y_r), indirectly estimated using actual and potential root water uptake (transpiration), indicated that the multiplicative stress response model (using the S-shape model) satisfactorily simulates measured yields and reproduces the effects of irrigation with saline waters on crop yields. An alternative scenario using a reduction of water requirements by 50% was investigated to assess an irrigation method with considerable water savings. As the results show that relative yields, Y_r, were only slightly reduced, the crop water requirements estimated by CROPWAT 8.0 must have been overestimated. The variation of the soil salinity in the root zone highlighted a high salinization risk in the short-term when water of 7 dS·m⁻¹ is used for irrigation.

On-farm trial was conducted from 2005 to 2008 to test the hypothesis that reduction of total dry matter (TDM) in crops can occur after a decreased radiation use efficiency (RUE) due to shortage of nitrogen and irrigation, we applied three irrigations treatments (D1, D2 and D3) and four nitrogen rates (N1, N2, N3 and N4). Photosynthetic active radiation absorbed or cumulative light interception (PARabs) and RUE of Durum wheat were measured. Results showed that D1N1 treatment recorded the highest LAI, PARabs, TDM and RUE. The maximum LAI was obtained 140 DAS (days after sowing) under treatment D1N2 (6.42) and the lowest LAI at the same phase belonged to treatment D2N4 (3.86). At the harvest, the maximum of TDM was 1487 g m-2 recorded under treatment D1N1. The minimum value obtained was 930 g m-2 under treatment D3N4. Also, PARabs was improved under D1N1 and D1N2 treatments. With reduced N application rates and irrigation doses, PARabs was decreased and the lowest values were observed under D3N4 condition. The RUE, varied from 1.55 g MJ-1 (D1N1) to 1.24 g MJ-1 (D3N4), was affected and decreased under deficit irrigation and low nitrogen conditions. In conclusion, the results of this study seem to show that D1N1 and D1N2 treatments can be beneficial for Durum wheat under field conditions in semi arid zone of Tunisia, for the purpose of improving RUE and maximizing grain yield.

Internet of Things (IoT) based precision irrigation system has proven to be promising tool for optimizing water use and crop production. In this study, two irrigation water-saving techniques, double-line drip irrigation (DI) and partial-root zone drying (PRD) were assessed on 27-year-old...

Three field experiments were conducted in the plot of Technical Centre for Potato and Artichoke during three cropping season 2009, 2010 and 2011.The objective of this research is to evaluate the effect of the partial root-zone drying irrigation technique (PRD) on the dry matter, yield, water consumption and water use efficiency of potato (Spunta Variety). Four treatments were applied from the initiation of tuberisation stage to potato harvesting: FI treatment received 100% of Etc; PRD80, PRD70, and PRD60 treatments received respectively: 80, 70 and 60% of FI at each irrigation event and it was shifted between the two sides of the plants every 2 to 10 days. The highest water consumption was observed in FI as 336.5, 376, and 341.8 mm in the 2009, 2010 and 2011 respectively, and the lowest was found in PRD60 as 280.4, 294.5, and 256.1 mm in the 2009, 2010 and 2011 respectively. The maximum tuber yield was obtained from the FI as 25.6, 42.9 and 39.1 tha-1, in the 2009, 2010 and 2011 respectively. There was no significant difference between FI and PRD60 with respect to tuber yields (LSD 5%).The highest water use efficiency (WUEY) was found in PRD60 as 13.4 kg m-3, in the second experiment (2010) and the lowest was found in PRD80 as 6.8 kg m-3 in the first experiment (2009). In the other hand, a linear relation between the accumulated total dry matter and the accumulated water consumption was able to be revealed.

Under climatic change and water scarcity conditions, the use of a precision irrigation system and crop-adapted irrigation strategy that takes into account climatic conditions is a major objective for scientists and farmers. The current study investigated the effects of different irrigation strategies, using low-cost smart tensiometers, on the vegetative growth, relative water content, gas exchange, and fruit quality of two young apple cultivars (Galaxy and Richared) in dry climate. Four irrigation treatments were considered: Control Irrigation [CI, 100% crop evapotranspiration (ETc)], Continuous Deficit Irrigation (CDI at 50% ETc), and Partial Root-zone Drying (PRD75 and PRD50 irrigated at 75% and 50% ETc, respectively). Results showed that shoot growth significantly decreased under CDI50% and PRD50% with a reduction of approximately 31.65% and 38.63% for Galaxy and Richared, respectively. A slight decrease in gas exchange parameters was recorded during the fruit ripening period, especially for Richared under CDI50% and PRD50%, while under PRD75%, the decrease was negligible. Moreover, a significant improvement in fruit quality was reported by an increase in firmness, TSS, that reached 19.50 and 17.50°Brix in Galaxy and Richared, respectively, under PRD75% and a decrease in acidity mainly in Richared. In conclusion, the deficit irrigation strategy PRD75% based on smart tensiometers data is the most recommended strategy in the region of the present study, considering its moderate effect on tree physiology and improvement in fruit quality.