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To select and introduce the best rapeseed genotypes under withholding irrigation, two field experiments were carried out in seasons 2015–2016 and 2016–2017 in Iran. Factorial arrangement of treatments was set up as RCBD with three replications. The experiment factors were two irrigation treatments (normal irrigation during the growing season and withholding irrigation from silique setting stage until the end of the growing season) and 17 genotypes of rapeseed. Grain yield, oil content and fatty acid contents were measured. The results revealed that oleic acid (62.15%) was the highest followed by linoleic (19.28%), linolenic (5.65%), palmitic (5.24%) and stearic acids (2.44%). ODR (oleic desaturation ratio) and LDR (linoleic desaturation ratio) were significantly affected by genotypes and irrigation treatments. The biosynthetic pathway of fatty acids affected by drought stress. This means that linoleic acid increases under withholding irrigation condition, while linolenic acid decreases in such a water deficit stress condition. The highest performance of qualitative and quantitative was detected in HL3721 genotype due to high values of grain yield (3892.45 kg ha−1), oil content (437.05 g kg−1), unsaturated fatty acids (87.63%) and low values of saturated fatty acids (7.98%), and it could be used under withholding irrigation in arid and semi-arid climates. [ABSTRACT FROM AUTHOR]

The agricultural production faces the inevitable challenges under the climate change conditions which threaten the food security. Under these circumstances, the increase of productivity can be regarded to ensure the food security. The interaction of genetic management determines the performance of given crop and environmental factors, and these elements should be simultaneously considered to have a sustainable production. To enhance the productivity and eco-efficiency of chickpea agro-ecosystems in the west and northwest of Iran, we optimized the genotype (G) × environment (E) × management (M) interactions to access optimum grain yield and water use efficiency using SSM-legume model. Three genotypes, eight locations, and 3 irrigation regimes were considered G, E, and M factors, respectively. The projections of future climate were conducted due to a 5–multi‐model ensemble under two emission scenarios (RCP4.5 and RCP8.5) for 2040–2070 using a methodology introduced by Agricultural Model Intercomparison and Improvement Project (AgMIP). The results indicated that across two RCPs, the climate change increased chickpea grain yield (11%) due to the positive effects of rising CO 2 concentration which slightly increased WUE (0.03%) based on an increase in the evapotranspiration (10.9%) and mean temperature (3.4%) and a decrease during the chickpea growing period (21.9%). However, these decreases and increases can be mitigated and boosted using an optimal G × E × M combination. ILC482 (mid-maturity genotype) × cold northwest environment × SI Pod-60 (supplementary irrigation of 60 mm at pod filling) was the best G × E × M interaction due to optimum WUE (6.98 kg ha-1 mm-1) and grain yield (1808.4 kg ha-1) for chickpea agro-ecosystems in upcoming period (2040–2070). In general, climate change and rising CO 2 concentration open up the opportunities to produce more grain yield in chickpea agro-ecosystems. Moreover, this production can be sustainably generated regarding WUE by adopting a suitable G × E × M interaction. • SSM-legume model accurately simulated chickpea development and growth. • Current management practices are not optimal for chickpea production. • Mid-maturity genotype × supplementary irrigation boosted grain yield at baseline. • At future, the best G × E × M interaction increased WUE (6.98 kg ha-1 mm-1). [ABSTRACT FROM AUTHOR]

• APSIM-Canola predicted seed yield and biomass reasonably well. • Mid-maturity genotype maximized rapeseed production in temperate agro-climatic zones (up to 2798.4 kg ha−1). • Withholding irrigation regimes were recommended as a solution for water-saving in arid and semi-arid regions. • Shifting towards the cooler climate zone (temperate agro-climatic zone) increased canola production (up to 3761.3 kg ha−1). The current study evaluated the development and growth of three major rapeseed genotypes (Hyola308, Hyola401, and RGS003 as early-, mid-, and late-maturity genotypes, respectively) as well as seed yield under different irrigation regimes (full irrigation, withholding irrigation at the flowering stage, withholding irrigation at the pod initiation stage, and withholding irrigation at the seed filling period) and also the spatial yield potential. APSIM-Canola model was applied to investigate the response of rapeseed genotypes to irrigation regimes in ten locations. Simulated results indicated that yield potential for rapeseed production was higher in the west which is a temperate agro-climatic zone (2852.6 kg ha−1) than in the southwest which is a hot agro-climatic zone (1885.1 kg ha−1). Although Hyola401 (the mid-maturity genotype) had the maximum seed yield (2798.4 kg ha−1), RGS003 (the late-maturity genotype) was found to be more drought-resistant due to a lower decrease in seed yield (18.1 %) under water-limited conditions compared with full irrigation conditions. The current findings suggest that the mid-maturity genotype has more yield potential in the studied locations (with different climates and soils) under full irrigation conditions due to higher seed yield, and the late-maturity genotype can be suggested as a resistant genotype for future breeding programs to introduce new-high-yielding genotypes with high drought tolerance, especially in drought-prone environments. Furthermore, withholding irrigation at seed filling onwards, which showed the lowest decrease in seed yield (13.6 %), can be recommended as a strategy for water-saving at the end of the growing season, and farmers can allocate irrigation water to other crops. [ABSTRACT FROM AUTHOR]