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Global climate change associated with increasing temperature and unreliable rainfall events will have consequences for crop production. Therefore, strategizing crop management gained the attention of crop scientists to curtail the adverse impacts of climate change on crop production. However, the projected effects of climate change on wheat may vary in different cropping systems as wheat production is reported to be significantly impacted by future climate change in major cropping systems worldwide. In the present study, ten experiments were conducted under irrigated (2007–2013) and rainfed (2010–2014) cropping systems of Pakistan to quantify the interactive impacts of future climate change (CO 2 , temperature, and rainfall) on wheat phenology, grain yield, crop evapotranspiration (ET c), and water use efficiency (WUE) using the DSSAT-CERES-Wheat. The DSSAT-CERES-Wheat was executed using 17 Global Climate Models (GCMs) and four Representative Concentration Pathways (RCPs; 2.6, 4.5, 6.0, and 8.5) to forecast the climate projections for 2030, 2050, and 2090. The average temperature at both sites will increase by 1.3, 1.9, 1.9, and 2.9 ℃ under RCP 2.6, 4.5, 6.0, and 8.5. The simulated output varies among GCMs, RCPs, CO 2 concentration, and future periods. A general reduction in wheat phenology, grain yield, ET c , and WUE was anticipated. However, higher CO 2 concentration and early maturity improved the WUE of wheat under irrigated and rainfed conditions. Nevertheless, this gain in WUE was at the cost of a relatively higher yield loss. Wheat yield is expected to decline by 2–19% and 9–30% under irrigated and rainfed conditions, respectively by aggregating the simulated future climate change impacts across GCMs and RCPs. Adaptation strategies to mitigate the climate change impacts on wheat production in irrigated and rainfed areas will be required. Our findings will serve as a foundation for designing future climate change adaptation strategies to sustain wheat production in Pakistan's irrigated and rainfed cropping systems. • Climate change jeopardize wheat productivity of irrigated and rainfed wheat world wide. • CERES-Wheat was executed using 17 GCMs and 4 RCPs for 2030, 2050, and 2090. • Increasing temperature and declining rainfall trend was observed for both locations. • Wheat phenology, grain yield, ET c , and WUE declined under future climate change. • Adaptation strategies are required to reduce adverse effects of climate change. [ABSTRACT FROM AUTHOR]

Wheat-fallow rotation is the major land-use system in the rainfed cropping system of Pakistan. Crop production in rainfed cropping systems is often jeopardized due to the scare and erratic seasonal patterns of rainfall. Climate change is further threatening the extent and productivity of rainfed agriculture in Pakistan. Climatic risk reduction strategies such as supplemental irrigation (SI) can assist in sustaining the productivity of rainfed agriculture. However, little has been done to investigate the potential of SI in sustaining the productivity of the rainfed cropping system of Pakistan despite the recent water resource developments in the rainfed regions of the country. For this purpose, a four-year (2010–2014) study was conducted to assess wheat yield and water productivity under rainfed and SI using a crop modeling approach. Calibrated CERES-Wheat was evaluated for its ability to simulate soil moisture dynamics, water productivity, canopy growth, in-season biomass, phenology, grain yield, and biomass at harvest based on soil water balance. Results showed a good to excellent performance of CERES-Wheat during evaluation. For example, combined values of soil moisture content between different layers, root zone soil moisture, seasonal crop evapotranspiration, in-season biomass growth, and canopy cover showed NRMSE values ranging from 13%–89%, 5–11%, 2–17%, 12–26%, and 13–22%, respectively. The NRMSE values of rainfall productivity of biomass and grain yield and water productivity of biomass and grain yield ranged from 18%, 16%, and 17%, 6%, respectively. The model was also applied to determine favorable management practices (appropriate planting dates from 15 October to 15 December at 15-day intervals and SI of 50 mm either at planting or 30 days after planting) as their determination under actual field conditions is laborious. Simulations for the best combination of planting date and SI suggested that higher crop yield and water productivity can be achieved with planting in November with irrigation applied 30 days after planting. • Climate change threatens the productivity of rainfed agriculture in Pakistan. • CERES-Wheat was applied to determine appropriate planting dates. • CERES-Wheat showed good to the excellent performance during evaluation. • Planting in November with irrigation after 30 DAP showed higher grain yield. • Planting in November with irrigation after 30 DAP showed higher water productivity. [ABSTRACT FROM AUTHOR]

Presence of heavy metals in agricultural soils is of major environmental concern and a great threat to life on the earth. A number of human health risks are associated with heavy metals regarding their entry into food chain. Various physical, chemical and biological techniques are being used to remove heavy metals and metalloids from soils. Among them, phytoremediation is a good strategy to harvest heavy metals from soils and have been proven as an effective and economical technique. In present review, we discussed various sources and harmful effects of some important heavy metals and metalloids, traditional phytoremediation strategies, mechanisms involved in phytoremediation of these metals, limitations and some recent advances in phytoremediation approaches. Since traditional phytoremediation approach poses some limitations regarding their applications at large scale, so there is a dire need to modify this strategy using modern chemical, biological and genetic engineering tools. In view of above, the present manuscript brings both traditional and advanced phytoremediation techniques together in order to compare, understand and apply these strategies effectively to exclude heavy metals from soil keeping in view the economics and effectiveness of phytoremediation strategies. [ABSTRACT FROM AUTHOR]

Wheat production in rainfed cropping systems is highly vulnerable to climate change, particularly in developing countries. Therefore, assessing the climate change impacts on rainfed wheat production is needed for ensuring global food security. Nitrogen (N) application has been reported to mitigate the impact of climate change on crop production, but its impact in rainfed cropping systems remains uncertain and/or rarely explored. Crop models have been commonly used for projecting the impacts of climate change on crop production. However, uncertainties from single-model simulation analyses call for multi-model simulation capabilities. Here, three models (APSIM-Wheat, CERES-Wheat, and Nwheat) were calibrated and evaluated for simulating phenology, agronomic traits, rainwater use efficiency (RWUE), and N use efficiencies under rainfed conditions in Pakistan. Five Global Circulation Models examined from 2041 to 2070 (RCP8.5) indicated an increase in mean growing temperature and changes in growing season rainfall between 1.6 and 4.9 ℃ and − 34 and + 39 %, respectively. Therefore, cool and dry, cool and wet, middle, hot and dry, and hot and wet projections were selected. All crop models successfully simulated the investigated parameters for different wheat cultivars and N application rates. APSIM-Wheat showed the best performance for validating the RWUE, plant N uptake, N utilization efficiency, and N uptake efficiency (NRMSE = 11.2–14.5 %), while CERES-Wheat performed well for grain yield and N use efficiency (NRMSE = 5.1–6.1 %). Nwheat showed a minimum average NRMSE for plant dry mass and harvest index (3.8–7.8%). All crop models predicted the maximum reduction in grain yield under hot and dry conditions. Compared to baseline, future climate change caused minimum and maximum grain yield reductions for Faisalabad-2008 (6 %) and AUR-809 (11 %), respectively, whereas, for N application rates, the minimum and maximum grain yield reductions were observed for N 0 (7 %), and N 140 (10 %), respectively. There were no significant differences in grain yield and RUWE across N application rates under future climate change. However, applying N from N 0 to N 70 significantly increases grain yield (82 %) and RWUE (77 %) across cultivars under future climate change. The findings would have valuable implications in tackling the negative impacts of future climate change on wheat production through the selection of suitable cultivars and formulating crop N management strategies for rainfed areas. • Performance of various crop-climate models was evaluated under rainfed conditions. • Future climate change jeopardizes wheat growth and development of rainfed wheat. • Selection of suitable cultivar can optimize wheat productivity under climate change. • Application of N can improve wheat productivity under future climate change. • Adaptation strategies are required to mitigate the negative effects of climate change. [ABSTRACT FROM AUTHOR]