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Wheat (Triticum aestivum L.) often faces salt stress and delayed sowing practices. These two events usually occur simultaneously in real field conditions that cause severe consequences on mineral balance, osmotic adjustment, reactive oxygen species (ROS) rampaging and antioxidant machinery. To address these issues, a two-year field-based study was directed at Jalalpur Pirwala Research Farm (JPRF), Multan-Pakistan. The experiment consisted of the following factors, a) timely sown under normal conditions (NS) and late sowing under normal conditions (LS) b) timely sown on saline conditions and late sown under saline conditions (LS+SS) c) foliar application of plant growth promoters hydrogen peroxide (H 2 O 2), salicylic acid (SA), thiourea (TU) and control (no spray) firstly to assess the influence of plant growth promoters (PGPRs) on the nutrient acquisition, osmoprotectants metabolism, ROS homeostasis and antioxidant clustering under SS, LS and their combined treatments. Results revealed that PGPRs foliar applications such as TU, followed by SA and H 2 O 2 played plausible roles in maintaining nutrient balance, osmoregulation, and circumventing the ROS. Exogenous application of TU increases the proline (18.24–20.01 %), total free amino acids (29.09 %-33.99 %), glycine betaine (3.43 %-15.34 %), total -soluble proteins (10.98 % -15.96 %) and total soluble sugars (15.21 %-20.36 %) for both years, under control conditions. Moreover, LS+SS followed by SS and LS declined the grain nutrient quality, shoot mineral content, and demolished the equilibrium between ROS and antioxidants, however, plants up-regulate the defensive mechanisms by enhancing the substantial content of antioxidants and osmoprotectants. So, wheat is moderately tolerant to combined LS+SS stress that evidently deteriorates its nutritional quality, but its performance can be enhanced by using PGPRs in delayed-sown wheat that often grows in marginally saline areas. [Display omitted] • Late-sown wheat faces severe nutrient imbalance under saline conditions. • Nutrient acquisition and, antioxidant metabolism play key role in wheat tolerance. • Plant growth promoters (PGPRs) improved the defence mechanisms and combat the effect of combined stress. • PGPRs maintain the nutrient balance and osmoregulation in late-sown wheat under salt stress. [ABSTRACT FROM AUTHOR]

Studies on the wheat response under late sowing (LS) and salinity stress (SS) are available, however, in rice-wheat and cotton-wheat cropping systems, wheat planting is often delayed resulting in co-occurrence of LS and SS in salt affected soils. This two-year field study was conducted to evaluate the influence of foliar application of plant growth regulators (PGRs) [thiourea (TU), salicylic acid (SA) and hydrogen peroxide (H2O2); water and no application were taken as control] on the productivity, grain quality and economic returns of timely-sown (TS) and LS wheat under normal (NC) and natural saline conditions (SS; EC 11.27 dS m− 1). Delay in sowing and planting in naturally saline soils caused a significant decrease in plant growth, grain yield, grain quality and net economic returns during both years of study. Late planting and SS caused a significant reduction in grain yield reduction by 40.58% and 34.72% (LS) and 40.66% and 42.89% (SS) compared with respective controls during 2021 and 2022, respectively. However, the influence of co-occurrence of LS and SS was more devastating than the individual stress causing 62.17% and 60.18% reduction in grain yield than the respective control during 2021 and 2022, respectively. However, the application of all PGRs improved the grain yield, grain quality and economic turnover under SS and LS stress. The order of improvement in grain yield by the application of PGRs treatments was TU > SA > H2O2. In conclusion, the application of different plant growth regulators improved economic returns, grain yield and quality attributes of late-sown wheat under saline conditions. In this regard, TU application was the most effective. [ABSTRACT FROM AUTHOR]

Wheat grain quality, an important determinant for human nutrition, is often overlooked when improving crop production for stressed environments. Climate change makes this task more difficult by imposing combined stresses. The scenarios relevant to climate change include elevated CO2 concentrations (eCO2) and extreme climatic events such as drought, heat waves, and salinity stresses. However, data on wheat quality in terms of climate change are limited, with no concerted efforts at the global level to provide an equitable and consistent climate risk assessment for wheat grain quality. Climate change induces changes in the quality and composition of wheat grain, a premier staple food crop globally. Climate‐change events, such as eCO2, heat, drought, salinity stress stresses, heat + drought, eCO2 + drought, and eCO2 + heat stresses, alter wheat grain quality in terms of grain weight, nutrient, anti‐nutrient, fiber, and protein content and composition, starch granules, and free amino acid composition. Interestingly, in comparison with other stresses, heat stress and drought stress increase phytate content, which restricts the bioavailability of essential mineral elements. All climatic events, except for eCO2 + heat stress, increase grain gliadin content in different wheat varieties. However, grain quality components depend more on inter‐varietal difference, stress type, and exposure time and intensity. The climatic events show differential regulation of protein and starch accumulation, and mineral metabolism in wheat grains. Rapid climate shifting impairs wheat productivity and causes grain quality to deteriorate by interrupting the allocation of essential nutrients and photoassimilates. © 2022 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

Foliar application of bio-stimulators is a successful strategy to enhance yield and quality in many crops. Moringa leaf extract (MLE) have plenty of antioxidants which are found as beneficial for regulating the physio-logical and metabolic processes in wheat under abiotic stresses. However, the mechanism of their action is not fully examined. This study was aimed to determine how foliar supplementation of MLE influences the nutrients content, antioxidant enzyme activities, and yield attributes of wheat cultivars in salinity conditions. Different concentrations of MLE were sprayed in two contrasting wheat cultivars; Galaxy-2013 (salt-sensitive) and Pasban-90 (salt-tolerant) under saline-sodic condition (9.5 dS m-1). All the foliar treatments were applied at critical growth stage, tillering, and booting stage. Exogenous application of MLE significantly increased chlorophyll (Chi) content and K+ level, and decreased Na+ level for both Pasban-90 and Galaxy-2013 cultivar when comparing with controlled sample that is in an order of Pasban-90>Galaxy-2013 cultivar>controlled sample. Interestingly, antioxidant enzyme activities (SOD, POD, CAT) were also increased for both cultivars. Moreover, exogoneous application of MLE significanlty improved yield attributes (spike length, grains per spike, 1000-grain weight, grain yield and biological yield) in both cultivars under salinity stress conditions. The findings of this study suggested that exogenous application of MLE can remarkably ameliorates salinity stress in wheat and salt tolerance is cultivar-specific. [ABSTRACT FROM AUTHOR]

Delay sowing of wheat is a common problem in Punjab that exacerbates serious yield loss. To reduce yield loss and improve yield, different combinations of foliar-applied bioregulator and micronutrients, control (CK), zinc (Zn), boron (B), thiourea (TU), Zn + B (ZnB), Zn + TU (ZnTU), B + TU (BTU), Zn + B + TU (ZnBTU) were applied at booting and grain filling stages in delayed sown wheat in 2017–18 and 2018–19. The results showed that ZnBTU treatment significantly increased leaf area index by 25.06% and 23.21%, spike length by 15.11% and 19.65% in 2017 and 2018, respectively, compared to CK. The ZnBTU treatment also increased 1000-grain weight by 21.96% and 22.01% in 2017 and 2018, respectively, compared to CK. Similarly, higher Zn, B and N contents in straw and grain were recoded for ZnBTU treatment which was statistically similar to ZnB and ZnTU treatments. Overall, ZnBTU treatment also increased the photosynthetic rate, transpiration rate, stomatal conductance by 46.67%, 26.03%, 76.25% and decreased internal CO2 by 28.18%, compared to CK, respectively. Moreover, ZnBTU also recorded the highest grain yield in 2017–18 (25.05%) and 2018–19 (28.49%) than CK. In conclusion, foliar application of ZnBTU at the booting and grain filling stages of delayed sown wheat could be a promising strategy to increase grain yield. [ABSTRACT FROM AUTHOR]

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Salinity stress can be mitigated by using the physiological seed enhancements. Kharchia 65 (salt tolerant) and PI.94341 (salt sensitive) genotypes were evaluated under salt stress (20 dS/m) by various priming treatments, that is hydropriming and halopriming (50 mmol, KCl and NaCl) in a pot study. Experiment was conducted in completely randomized design under factorial arrangements with three replications. Priming agents improved the final emergence percentage (FEP), emergence index (EI) and reduced the mean emergence time of both wheat genotypes under normal and saline conditions as compared to non-primed seed. Priming treatments elicited the efficiency of wheat seedlings by increasing both Fv/Fm and Ft under both normal and salt stress conditions which were strongly linked with low Na+ and high K+. In conclusion, all three priming agents effectively nullified the deleterious effects of salt stress by improving seed emergence and triggering the physiological attributes of wheat. [ABSTRACT FROM AUTHOR]

Salinity is a leading threat to crop growth throughout the world. Salt stress induces altered physiological processes and several inhibitory effects on the growth of cereals, including wheat (Triticum aestivum L.). In this study, we determined the effects of salinity on five spring and five winter wheat genotypes seedlings. We evaluated the salt stress on root and shoot growth attributes, i.e., root length (RL), shoot length (SL), the relative growth rate of root length (RGR-RL), and shoot length (RGR-SL). The ionic content of the leaves was also measured. Physiological traits were also assessed, including stomatal conductance (gs), chlorophyll content index (CCI), and light-adapted leaf chlorophyll fluorescence, i.e., the quantum yield of photosystem II (Fv′/Fm′) and instantaneous chlorophyll fluorescence (Ft). Physiological and growth performance under salt stress (0, 100, and 200 mol/L) were explored at the seedling stage. The analysis showed that spring wheat accumulated low Na+ and high K+ in leaf blades compared with winter wheat. Among the genotypes, Sakha 8, S-24, W4909, and W4910 performed better and had improved physiological attributes (gs, Fv′/Fm′, and Ft) and seedling growth traits (RL, SL, RGR-SL, and RGR-RL), which were strongly linked with proper Na+ and K+ discrimination in leaves and the CCI in leaves. The identified genotypes could represent valuable resources for genetic improvement programs to provide a greater understanding of plant tolerance to salt stress. [ABSTRACT FROM AUTHOR]

A pot study was conducted to explore the effectiveness of zinc oxide nanoparticles (ZnO NPs) foliar exposure on growth and development of wheat, zinc (Zn) and cadmium (Cd) uptake in Cd-contaminated soil under various moisture conditions. Four different levels (0, 25, 50, 100 mg/L) of these NPs were foliar-applied at different time periods during the growth of wheat. Two soil moisture regimes (70% and 35% of water holding capacity) were maintained from 6 weeks of germination till plant harvesting. The results revealed that the growth of wheat increased with ZnO NPs treatments. The best results were found in 100 mg/L ZnO NPs under normal moisture level. The lowest Cd and highest Zn concentrations were also examined when 100 mg/L NPs were applied without water deficit stress. In grain, Cd concentrations decreased by 26%, 81% and 87% in normal moisture while in water deficit conditions, the Cd concentrations decreased by 35%, 66% and 81% compared to control treatment when ZnO NPs were used at 25, 50 and 100 mg/L. The foliar exposure of ZnO NPs boosted up the leaf chlorophyll contents and also decreased the oxidative stress and enhanced the leaf superoxide dismutase and peroxidase activities than the control. It can be suggested that foliar use of ZnO NPs might be an efficient way for increasing wheat growth and yield with maximum Zn and minimum Cd contents under drought stress while decreasing the chances of NPs movement to other environmental compartment which may be possible in soil applied NPs. • Cadmium (Cd) and water stress negatively affected shoot, roots and grain yield of wheat. • Foliar application of zinc oxide nanoparticles (ZnO NPs) improved the growth under stress. • Foliar ZnO NPs improved chlorophyll contents and minimized oxidative stress in shoots. • Foliar ZnO NPs increased Zn and decreased Cd contents in wheat grains under Cd and water deficient stress. [ABSTRACT FROM AUTHOR]

• Combined heat and drought stress (H + D) impact grain development in bread development. • H + D stress arrests cell division and expansion and damages pollen grains. • The stresses also cause pollen sterility and reduces stigma receptivity. • Crop breeding, genomics and agronomic practices can help improve stress tolerance. High temperature and drought stress during grain formation in wheat affect grain development. Along with the increasing human population pressure are predicted increases in temperature and decline in water resources. Wheat genotypes that can better tolerate combined heat and drought stress (H + D) are needed to ensure sustainable food production. Wheat can tolerate water-deficit conditions, but few studies have investigated the associated wheat grain developmental characteristics and stress tolerance mechanisms. H + D stress disrupts meiosis, arrests cell division and expansion, damages pollen grains and the pollen sac, causes pollen sterility and shrivels anthers, reduces stigma receptivity, aborts ovules, and disrupts cell division in the central and peripheral endodermis, thus reducing the breadth and length of the endodermis. The subsequent reduction in grain sink potential eventually leads to reduced mature grain mass and shriveled grain to a considerable extent. However, genotypic variability exists for drought and heat-induced disruption and tolerance in wheat. Combined H + D tolerance can be induced through genetic engineering, agronomic practices, and marker-assisted selection. This review describes the current state of knowledge on the effect of combined H + D stress and possible management strategies to avert damage to wheat grain during grain development and maturation. [ABSTRACT FROM AUTHOR]

Amid rising energy crises and greenhouse gas (GHG) emissions, designing energy efficient, GHG mitigation and profitable conservation farming strategies are pertinent for global food security. Therefore, we tested a hypothesis that no-till with residue retaining could improve energy productivity (EP) and energy use efficiency (EUE) while mitigating the carbon footprint (CF), water footprint (WF) and GHG emissions in rice-wheat double cropping system. We studied two tillage viz., conventional and conservation, with/without residue retaining, resulting as CT0 (puddled-transplanted rice, conventional wheat -residue), CTR (puddled-transplanted rice, conventional wheat + residue), NT0 (direct seeded rice, zero-till wheat -residue), and NTR (direct seeded rice, zero-till wheat + residue). The overall results showed that the NTR/NT0 had 34% less energy consumption and 1.2-time higher EP as compared to CTR/CT0. In addition, NTR increased 19.8% EUE than that of CT0. The grain yield ranged from 8.7 to 9.3 and 7.8–8.5 Mg ha−1 under CT and NT system, respectively. In NTR, CF and WF were 56.6% and 17.9% lower than that of CT0, respectively. The net GHG emissions were the highest (7261.4 kg CO 2 ha−1 yr−1) under CT0 and lowest (4580.9 kg CO 2 ha−1 yr−1) under NTR. Notably, the carbon sequestration under NTR could mitigate half of the system's CO 2 -eq emissions. The study results suggest that NTR could be a viable option to offset carbon emissions and water footprint by promoting soil organic carbon sequestration, and enhancing energy productivity and energy use efficiency in the South Asian Indo-Gangetic Plains. • Net GHG emissions were 58.5% greater in CT0 compared to NTR. • No-till with residue returning (NTR) decreased water and C footprints. • Overall, no-till had ∼18% less input cost than conventional tillage. [ABSTRACT FROM AUTHOR]

Excess amount of cadmium (Cd) in arable soils and shortage of good quality water are the major abiotic factors affecting the crop yield which needs immediate solution to feed the increasing population worldwide. Recently, nanoparticles (NPs) are widely used in various industries including agriculture which is due to the unique properties of NPs. Among NPs, iron (Fe) NPs might be used to alleviate the abiotic stresses in crops but limited informations are available in the literature about the role of Fe-NPs in crops under metal stress. The present study was designed to highlight the efficiency of Fe-NPs on Cd accumulation in Cd and drought-stressed wheat. Wheat plants were grown in Cd-contaminated soil after the supply of different levels of Fe-NPs and two water regimes were introduced in the soil in latter growth stages of the plants. Cadmium and drought stress negatively affected the wheat photosynthesis, yield and caused oxidative stress in leaves with excess accumulation of Cd in grains and other plant tissues. The NPs improved the photosynthesis, yield, Fe concentrations and diminished the Cd concentrations in tissues. The NPs alleviated the oxidative stress in leaves and the efficiency depends on the NPs concentrations applied in the soil. The results obtained indicated that Fe-NPs may be employed aiming to get wheat grains with excess Fe and decreased Cd contents. However, field investigations with various sizes, shapes and levels of NPs are needed before final recommendations to the farmers. • Combined cadmium (Cd) and drought decreased the yield of wheat. • Drought stress increased the Cd concentration in grains of wheat. • Iron oxide nanoparticles (Fe NPs) increased the wheat growth under Cd + drought stress. • Fe NPs increased photosynthesis and reduced oxidative stress in Cd and drought-stressed wheat. • Fe NPs decreased Cd and increased Fe concentrations in wheat grains. [ABSTRACT FROM AUTHOR]