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BACKGROUND: Low recovery of conventional fertilizers remains a significant bottleneck for maize production globally. In particular, with phosphate fertilization, zinc (Zn) is prone to precipitation in soil, reducing recovery of both phosphorus (P) and Zn by maize. RESULTS: The present study was designed to investigate the synergistic effect of zinc oxide (ZnO) nanoparticles (NPs) and P on maize crop growth, yield, and nutrient uptake under ZnO seed coating and foliar application in a randomized complete block design. However, plants were subjected to two ZnO NPs levels (0.5 and 12 kg ha−1) amended with two P levels (45 and 90 kg ha−1). ZnO NPs, especially in the form of foliar application, with a P dose of 90 Kg ha−1 significantly (P < 0.05) improved maize crop growth, yield, and nutrient uptake compared with control. In comparison with the control group, plants grown in these conditions absorbed higher levels of Zn and P. Zn uptake rose to 16.34 g ha−1, 137.88 g ha−1, and 166.89 g ha−1 in roots, grains, and stover respectively, and P uptake increased to 0.80 mg kg−1, 10.066 mg kg−1, and 12.17 mg kg−1 respectively. Additionally, seed emergence rate, plant height, and cob length increased by up to 2%, 1177 cm2, and 3.3 cm respectively compared with control. Furthermore, Zn use efficiency was increased up to 38.55% in ZnO NPs foliar application. CONCLUSIONS: Application of ZnO NPs at 0.5 kg ha−1 in the form of foliar application with 90 kg ha−1 P dose produced a more pronounced increment in the parameters studied than ZnO NPs seed coating did. © 2024 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

Zinc-oxide nanoparticles (ZnO-NP) effect on crop physiology and zinc recovery remains poorly studied for acidic-sandy soils. To address this, greenhouse pot (plastic-pots, 6 kg soil, maize) experiments with ZnO-NP (50, 100, 150, 200 mg kg−1) applied via different methods (soil-drench, seed-coating and foliar-spray) was conducted in a 60 days study. Results revealed that ZnO-NP via seed-coating (100 mg kg−1) and soil-drench (150 mg kg−1) enhanced shoot and total P uptake, while ZnO-NPs (foliar) (50 mg kg−1) enhanced maize growth (6–11%), with agronomic and physiological improvements ultimately resulted in greater biomass (16–20%), Zn agronomic efficiency and uptake. Compared to ZnSO4 treatment and the control, seed-coating with 100 mg kg−1 ZnO-NP increased leaf chlorophyll and pigment content by 12–127%. Principal component analysis revealed a close association among growth traits, plant pigments, fluorescence parameters, total Zn and P concentration, and uptake with total biomass as influenced by ZnO-NPs. Thus, compared to conventional ZnSO4 and higher dosages of ZnO-NPs, foliar-spray of ZnO-NP at 50 mg kg−1, seed-coating at 100 mg kg−1, or soil-drench at 150 mg kg−1 increased maize biochemical characteristics, growth, biomass, and Zn agronomic efficiency. These elucidate important implications of ZnO-NP application for increasing plant development and Zn biofortification in acidic-sandy soils. [ABSTRACT FROM AUTHOR]

Introduction: Low agricultural nutrient input efficiency remains a significant impediment for crop production globally. To address this issue in cotton agroecosystems, there is a need to develop sustainable crop nutrient management strategies to achieve high crop yields. We hypothesized that organic liquid fertilizer (OF) combined with reduced chemical fertilizer (CF) would enhance cotton yield by improving leaf functioning and soil properties. However, the underlying mechanism and its related process is poorly understood. Methods: This study explored the effects of OF combined with reduced CF on cotton yield, physiology and soil properties. Treatments included a single application of CF (CF: N, P2O5 and K2O applied at 228, 131 and 95 kg ha-1) and combined applications of OF and CF (OF0.6-OF1.4) in the following ratios: OF0.6, OF+60% CF; OF0.8, OF+80% CF; OF1.0, OF+100% CF; OF1.2, OF+120% CF; OF1.4, OF+140% CF. Results and discussion: The result showed that compared with CF, OF0.8, OF1.0 and OF1.2 increased soil organic matter (SOM) content by 9.9%, 16.3% and 23.7%, respectively. Compared with CF, the OF0.6, OF0.8, OF1.0, and OF1.2 treatments increased leaf area (LA) by 10.6-26.1%, chlorophyll content (Chl content) by 6.8 -39.6%, and the efficiency of photosystem II (PSII) light energy (Y(II)), electron transfer rate of PSII (ETR) and photochemical quenching (qP) by 3.6-26.3%, 4.7 -15.3% and 4.3-9.8%, respectively. The OF0.8 treatment increased net photosynthetic rate (Pn), stomatal conductance (Gs) and transpiration rate (E) by 22.0%, 27.4% and 26.8%, respectively, resulting in higher seed cotton yield. The seed cotton yield and economic coefficient were positively correlated with Pn, E, Gs and Y(II) from the full boll stage to the boll opening stage. In summary, the OF0.8 treatment can maintain a high SOM content and photosynthetic performance with reduced chemical fertilizer input without sacrificing yield. The integration of OF+80% CF (OF0.8) is a promising nutrient management strategy for highly efficient cotton production undermulch drip irrigation systems. [ABSTRACT FROM AUTHOR]

Low Zinc (Zn) availability in alkaline calcareous soil is one of the major causes of low cereal yield and quality. Conventional application of Zn sulfate (ZnSO4) fertilizer through soil application attains minimal Zn efficiency as it is readily fixed in such soils. Oxozinc nanofiber (ZnONF) was evaluated for wheat Zn biofortification using different application methods to tackle this issue. Pots in triplicate (each with 7 kg soil) were arranged in a completely randomized design with a control treatment without Zn application. The conventional ZnSO4 fertilizer recommended dose (5.5 µg Zn kg−1 of soil) was used for comparison and applied through soil addition, foliar spray, and seed priming, while the ZnONF was applied through foliar spray, seed coating, and seed priming (@ 0.5 kg ha−1) either alone or in combination with ½ZnSO4 applied to the soil. The application of ZnONF significantly improved wheat plant growth as evidenced by increased plant height (14.5%), spikelets per spike (13.7%), and Zn use efficacy (611%) regardless of application methods as compared to control. The highest Zn uptake efficiency (34%) for nanofibers was obtained for theseed primed, followed by seed coating (23%) and foiar application (7%), respectively. Moreover, at the combined ZnONF and ½ZnSO4 application, further improvements for spike length, number of spikelets spike−1, grain, leaf, root, and stem Zn concentrations, as well as their respective Zn contents, were noted. These results elucidated that Zn nutrition with ZnONF was either at par with or higher than the conventional ZnSO4 fertilizer application despite significantly reduced ZnONF quantity, irrespective of the application method used. Additionally, the combined ZnONF and ½ZnSO4 (foliar spray, seed coating, or seed priming) maximized the crop Zn accumulation, wherein the ½ZnSO4 + ZnONF through foliar application exceeded grain Zn biofortification. Thus, various Oxozinc nanofibers application modes may be recommended for wheat biofortification either separately or in combination with ZnSO4 in Zn deficient calcareous soils for improved Zn nourishment. [ABSTRACT FROM AUTHOR]

Biochar fertilization improves soil fertility and carbon sequestration, implying agricultural and environmental advantages. The effect of different sized previously applied biochar and biofertilizer agents on succeeding crops remains poorly known for legume–cereal cropping cycles. This study compared different particle-sized biochar and biofertilizer strains applied to lentils for their residual impact on subsequent maize growth, nutrition, and soil fertility without further polluting the environment. Three particle sizes (<2, 2–5, 5–10 mm) of Babul tree (Acacia arabica) wood biochar was obtained through grinding and sieving and applied prior to the lentil (first) crop at a rate of 500 g m−2. The commercial Rhizobium leguminosarum products Biozote-N and Rhizogold were inoculated to lentil seeds before sowing. The effect of biochar and biofertilizer agents on the succeeding maize (second) crops was evaluated for soil and crop performance. Findings revealed that particle sizes of <2 mm biochar and Biozote-N inoculation enhanced plant height, leaf area and leaf area index, biological yield, and thousand grain weight of the subsequent maize crop. Maize grain yield was enhanced by 2.5%, tissue N uptake by 15%, nitrogen uptake efficiency by 17%, grain protein content by 15%, extractable P by 17%, and soil bulk density by 3% with a residual biochar particle size of <2 mm and Biozote-N inoculation. It was concluded that the finely grounded (<2 mm) biochar particle combined with inoculation of Biozote-N was superior to larger particle sizes for enhancing crop growth and improving soil fertility status at the residual level, benefiting the subsequent crop in a legume–cereal rotation system. [ABSTRACT FROM AUTHOR]

Flood defence assets such as earth embankments comprise the vital part of linear flood defences in many countries including the UK and protect inland from flooding. The risks of flooding are likely to increase in the future due to increasing pressure on land use, increasing rainfall events and rising sea level caused by climate change also affect aging flood defence assets. Therefore, it is important that the flood defence assets are maintained at a high level of safety and serviceability. The high costs associated with preserving these deteriorating flood defence assets and the limited funds available for their maintenance require the development of systematic approaches to ensure the sustainable flood-risk management system. The integration of realistic deterioration measurement and reliabilitybased performance assessment techniques has tremendous potential for structural safety and economic feasibility of flood defence assets. Therefore, the need for reliability-based performance assessment is evident. However, investigations on time-dependent reliability analysis of flood defence assets are limited. This paper presents a novel approach for time-dependent reliability analysis of flood defence assets. In the analysis, time-dependent fragility curve is developed by using the state-based stochastic deterioration model. The applicability of the proposed approach is then demonstrated with a case study.

This paper presents a new analytical method for evaluating concrete crack development, estimating reinforcing bar bond strength degradation and predicting residual flexural strength of concrete beams affected by reinforcement corrosion. First, cracking development in cover concrete due to reinforcement corrosion is investigated by using the reinforcing bar-concrete model where realistic concrete properties such as bilinear tension softening law for the cracked concrete are considered. Then, the bond strength evolution of the corroded reinforcing bar is evaluated by considering the contributions from adhesion, concrete confinement, and corrosion pressure acting at the bond interface. The effects of cover concrete cracking on the corroded reinforcing bar bond strength are analytically investigated. On the basis of the estimated concrete crack width and reinforcing bar bond strength degradation due to corrosion, the residual flexural strength of corroded concrete beams is predicted by assuming new strain compatibility at the reinforcing bar bond interface. Finally, the results obtained from the proposed methods are examined by experimental and field data available from various sources. From the results, the residual flexural strength of corroded reinforced concrete beams can be largely dependent on the residual bond strength of corroded reinforcing bar, and the failure mode of the beams may be changed from reinforcing bar tensile yielding to reinforcing bar anchorage failure due to reinforcing bar bond strength degradation. The results also show that the proposed analytical approach is capable of providing accurate predictions for concrete cracking, bond strength degradation, and residual flexural strength of corrosion-damaged reinforced concrete beams. [ABSTRACT FROM AUTHOR]

The reliability of reinforced concrete structures is frequently compromised by the deterioration caused by reinforcement corrosion. Evaluating the effect caused by reinforcement corrosion on structural behaviour of corrosion damaged concrete structures is essential for effective and reliable infrastructure management. In lifecycle management of corrosion affected reinforced concrete structures, it is difficult to correctly assess the lifecycle performance due to the uncertainties associated with structural resistance deterioration. This paper presents a stochastic deterioration modelling approach to evaluate the performance deterioration of corroded concrete structures during their service life. The flexural strength deterioration is analytically predicted on the basis of bond strength evolution caused by reinforcement corrosion, which is examined by the experimental and field data available. An assessment criterion is defined to evaluate the flexural strength deterioration for the time-dependent reliability analysis. The results from the worked examples show that the proposed approach is capable of evaluating the structural reliability of corrosion damaged concrete structures. [ABSTRACT FROM AUTHOR]

Bond strength deterioration in corrosion-damaged reinforced concrete structures significantly affects serviceability and load-carrying capacity in their remaining service life. This paper presents a new analytical model for predicting the cracking development in the surrounding concrete and the residual bond strength of rebar in concrete structures due to reinforcement corrosion. The proposed analytical method adopts the thick-walled cylinder model for the cover concrete and considers the realistic properties of the corrosion-induced cracked concrete such as anisotropic behavior, residual tensile strength, and reduced tensile stiffness. As corrosion progresses, three phases for bond strength evolution associated with concrete cracking development are defined and the corresponding corrosion levels in each phase are determined. By using the constructed new governing equation, the crack width growth in the concrete cover and the radial bursting pressure at the bond interface are evaluated. The ultimate bond strength is then estimated from the contributions of adhesion, confinement, and corrosion pressure as a function of corrosion level. Finally, the effectiveness of the proposed analytical model is demonstrated by comparing the predicted results with experimental data available, and the results show that the proposed model is useful for predicting the bond strength evolution of the corroded rebar in concrete structures. [ABSTRACT FROM AUTHOR]