The extensive use of broad-spectrum antibiotics, of which humans and animals metabolize less than 30

Soil contamination with cadmium (Cd) poses a serious threat to wheat production by impairing soil biological health and reducing grain quality. Organic materials such as pressmud may mitigate metal-induced stress to wheat by restoring soil microbial activities, improving nutrient uptake and limiting Cd absorption from soil. In this study, a pot experiment was conducted using salt-affected sandy loam soil spiked with Cd at 0, 25 and 50 mg kg⁻1. After two weeks, pressmud was applied to soil at 0, 10 and 20 g kg⁻1, and wheat was sown. Plants were harvested at the seedling stage and at maturity to assess soil biological activity, plant antioxidants, growth, yield and grain Cd accumulation. Cadmium contamination significantly suppressed soil biological activity, reducing soil respiration by 6–19

Iodine uptake by plants is thought to be affected by iodine form, soil pH and organic matter content. We investigated time-dependent water-soluble iodine in soil and its uptake by maize in limed and humic acid amended soil fertilized with iodide and iodate. A laboratory incubation and a wire-house pot experiment were conducted. In both, iodine was applied at 3 mg kg⁻1 soil, while lime (CaCO₃) and humic acid were each applied at 3 g kg⁻1 soil. Water-soluble iodine (WSI) in iodide-fertilized soil stabilized within one month, except in limed soil where a slight decline occurred after the second month. In contrast, iodate-fertilized soil showed 2–6 times higher WSI than iodide, gradually decreasing from 938 to 562 µg kg⁻1 over three months. Humic acid did not affect WSI in iodide-treated soils but reduced it by 24–48

BackgroundSelenium (Se) concentration is low in animal meat and human beings due to its insufficient levels in forage and feed sources.AimsThis study investigates the effects of nitrogen (N) rates and N forms to improve the biomass and Se concentration in maize forage.MethodsThe soil in the pots was fertilized with N at the rates of 165 and 330 mg kg-1 without and with 3,4-dimethylpyrazole phosphate (DMPP). DMPP was added to soil at the rate of 0.01% of added N, whereas Se was added at the rate of 40 mu g kg-1. In the following experiment, the effect of N forms (NH4+-N, NO3--N and NH4+-N +O3--N) was evaluated on the growth and the accumulation of Se, N and phosphorus (P) in maize shoots in Se-fertilized (40 mu g kg-1) and control soils. The Se-fertilized and controls soils were designated as Se(+) and Se(-), respectively. The soil texture was sandy and its pH was moderately acidic (5.40).ResultsThe DMPP-treated soil had 27%-42% higher NH4+-N content at harvest than the non-treated soil. The DMPP treatment of soil also increased shoot Se content by 19%-23% and Se uptake by 37%-42%. A negative correlation was found between NO3--N: NH4+-N ratio and shoot Se uptake, suggesting that NO3--N negatively affected Se uptake by maize. Results of second experiment depicted that applying NH4+-N led to higher shoot Se content and uptake than NO3--N. In case of Se-unfertilized soil, adding NH4+-N produced 14% and 56% more shoot Se content and uptake, respectively, whereas these increases were 39% and 83% on Se-fertilized soils. Similar to Se uptake, plants fed with NH4+-N had higher P and N uptake by maize shoots than that fed with NO3--N. The SPAD value and shoot biomass were also higher by applying NH4+-N than NO3--N.ConclusionThese results imply that N fertilization, specifically combined application of Se and ammonium-based fertilizers could improve biomass yield and Se content of maize, which is likely to yield maize grains with improved Se contents.

The textile industry generates a substantial quantity of wastewater containing carcinogenic and mutagenic dyes, posing significant environmental risks. Using microalgae to remove dyes from wastewater offers an eco-friendly solution to this issue. Accordingly, this study aimed to characterize textile wastewater and evaluate the potential of Chlorella sorokiniana strain HIN-3 for dye removal. Twenty textile wastewater samples were analyzed for pH, electrical conductivity, total dissolved solids (TDS), chlorides, cadmium, lead, chromium, nickel and color. The ability of strain HIN-3 to biodegrade seven structurally distinct dyes was investigated. The effects of metals (cadmium, lead and copper), TDS (1300–5200 mg L−1) and nitrogen sources (NaNO3, NH4Cl and urea) on dye degradation were evaluated. Additionally, six dye-rich industrial effluents were treated with microalgae for dye removal, and the activities of dye-degrading enzymes were measured. Results revealed that 25

Iron-EDTA becomes unstable above pH 6.5, resulting in competition among metal ions (Fe, Cu, Zn, and Mn) for EDTA and reduced Fe availability. This study examined nutrient precipitation dynamics and interactions between chelated and sulfate forms of Zn, Mn, and Cu with Fe-EDTA in fava bean and maize under increasing alkalinity (0, 5, and 15 mM NaHCO3). In fava bean, chelated micronutrients significantly increased shoot Fe, P, and Zn concentrations and improved metabolic activity and oxidative stress tolerance. Maize was more sensitive to alkalinity but showed similar nutrient responses at 5 mM NaHCO3. Speciation modeling (MINEQL+5.0) indicated Fe displacement from Fe-EDTA at high pH, forming insoluble FePO4 and Fe(OH)3. Incubation studies demonstrated that Fe-HBED maintained higher Fe, Ca, and P solubility than Fe-EDTA and Fe-DTPA under alkaline conditions. SEM-EDX analysis linked stable Fe chelates to lower P in precipitates. Results highlight Fe-HBED's effectiveness in ensuring Fe and P availability under alkalinity.

Wastewater can be used in hydroponic systems to grow crop plants, offering a sustainable solution to water scarcity and nutrient recycling. However, contaminants like Cu and Zn can affect crop yield. This study aimed to assess the effects of Cu- and Zn-induced toxicity on growth, physiology, photosynthesis, biochemical characteristics, element concentrations, and leaf distribution patterns in buckwheat. The experiment consisted of nine treatments (0, Cu5, Cu10, Zn50, Zn100, Cu5Zn50, Cu5Zn100, Cu10Zn50 and Cu10Zn100 mg L−1) with four replications in a completely randomized design. The obtained data were analyzed by ANOVA and Tukey's HSD tests. A two-way clustering based on Euclidian distance was performed to understand the relationships between the measured parameters better. The results showed that Cu and Zn at higher and combined levels notably decreased fresh and dry weight, nitrogen balance index, chlorophylls, photosystem II (PSII) efficiency, and PSII quantum yield compared to the control. Conversely, the anthocyanin and flavonoids contents were increased compared to the control. Shoot Cu and Zn concentrations and uptake were dose-dependent; however, Cu and Zn interactions at higher levels were antagonistic. Micro-XRF element distribution analysis of leaves showed that Cu and/or Zn treatment affected element partitioning between mesophyll and vascular tissue. Mesophyll to vein metal concentration ratios (MeVeR) showed that at higher Cu levels (Cu10), more Cu was transported into the mesophyll, making Cu more toxic due to interference with photosynthesis, while at high Zn levels (Zn100), Zn was more efficiently sequestered in veins.

A comparative pot study was performed to assess the toxic effects of copper (Cu) and/or zinc (Zn) contaminated wastewater (WW) irrigation on the growth, physiology, and element concentration of wheat grown for two months. The treatments included irrigation with uncontaminated wastewater (WW) as control, Cu-contaminated WW (CuWW), Zn-contaminated WW (ZnWW), and Cu + Zn contaminated WW (CuZnWW) in a completely randomized design. Compared to ZnWW, irrigation with CuWW or CuZnWW had severe effects on growth, physiology, and mineral absorption by wheat. Irrigation with CuWW or CuZnWW reduced shoot length, root length, root and shoot dry weights by 44-45%, 54-56%, 5-6%, and 33-34%, respectively, against WW control. Similarly, these treatments diminished chlorophyll a, b, carotenoids, and SPAD by 33-34%, 59-60%, 49-51%, and 26-27%, respectively. Conversely, contaminated irrigation improved the total polyphenols, polyphenolic acids, total flavonoids, and antiradical activity, however, a maximum increase in these parameters up to 65% was observed when irrigated with ZnWW. Pearson correlation showed that the decline in growth and physiology of wheat was negatively correlated with shoot metal concentration and uptake. Dehydrogenase activity is severely hampered by CuWW or CuZnWW and to a lesser extent by ZnWW as well. These results suggest that irrigation with contaminated WW adversely affects wheat growth and physiology, however, ZnWW is found to be less toxic to wheat crops than Cu. Thereby, this data highlights the need for a tailored approach to prioritize the metal (Zn) with lower toxicity during the use of WW in irrigation practice. PRACTITIONER POINTS: Cu-contaminated wastewater (20 ppm Cu) substantially reduced the growth and physiology of wheat. Zn (80 ppm) contaminated wastewater was found lesser toxic compared to Cu. Wheat irrigation with contaminated wastewater increased biologically active compounds in wheat shoot. Contaminated wastewater affected minerals concentration in the root and shoot part of wheat. Dehydrogenase activity in soil is less affected by Zn-contaminated wastewater. Irrigation with wastewater and leftover crop residues resulted in the accumulation of organic matter in soil.

Conventional P fertilizers, like di-ammonium phosphate (DAP), are highly reactive in alkaline calcareous soils, and exhibit low phosphorus use efficiency (PUE 20

Green waste compost (GWC) could alleviate the toxicity of Cu/Zn-contaminated wastewater (WW) to plants, but its differential behaviour in neutral and acidic soils remains unelucidated. Therefore, this pot study evaluated the alleviative effect of GWC on the toxicity of Cu and/ or Zn contaminated wastewater to soil dehydrogenase activity (DHA), growth, physiology and metal accumulation by common pea in acidic and neutral soils. The four WW treatments were: uncontaminated WW, Cu-contaminated WW, Zn-contaminated WW, and Cu+Zn-contaminated WW. Thus, there were 16 treatment combinations (4 wastewater- × 2 soils- × 2 compost levels), each having three replicates. Contaminated WW had statistically similar negative effects on soil DHA, growth and chlorophyll contents of pea plants in both soils. Pea plants accumulated more Cu and Zn in acidic-pH soil than in neutral soil. The ameliorative effect of the GWC amendment was statistically similar in both soils. The GWC improved soil organic matter (30–49

A huge volume of industrial wastewater laden with toxic heavy metals, including cadmium, lead, nickel and copper, is discharged into the environment without treatment. Pressmud, a byproduct of sugar industry, could serve as an efficient, low-cost and environment friendly amendment for the biosorptive removal of lead (Pb) from wastewater. This study aimed to assess the biosorption efficiency of pressmud in removing Pb from water. Primarily, it evaluated the biosorption potential of pressmud for Pb, and compared it with other amendments such as, citrus waste, rice straw, biochar and activated carbon. Subsequently, the biosorption of Pb by the pressmud was measured at different temperatures (20-45 °C), pH (5-10) and biosorbent doses (2-10 g L-1). The kinetics of Pb biosorption onto pressmud were studied by pseudo-first-order (PFO), pseudo-second-order (PSO) and Elovich models. The equilibrium isotherms were studied for a range of Pb concentrations (25-500 mg L-1) using Freundlich, Langmuir and Sips models. Moreover, the pressmud was characterized by Fourier-transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), Scanning electron microscope (SEM) and Brunauer-Emmett-Teller (BET). The pressmud exhibited a biosorption capacity of 5.30 mg g-1 for Pb, while surpassing other biosorbents. The biosorption capacity of rice straw, biochar, and activated carbon for Pb was 4.44, 1.94, and 0.49 mg g⁻¹, respectively. The highest biosorption capacity of pressmud was observed with contact time of 4 h, biosorbent dose of 8 g L-1, temperature of 37 °C, pH 7 and Pb concentration of 500 mg L-1. The biosorption of Pb onto pressmud followed the PFO reaction with R2RMSE and SSE of 0.981, 0.0333 and 0.0067, respectively. Langmuir model best described the adsorption behavior of Pb and predicted the maximum biosorption capacity of 43.7 mg g-1. FTIR, SEM and BET depicted that the adsorption of Pb by pressmud could be attributed to the presence of various functional groups, highly porous nature and a large surface area. Thus, pressmud could be used as a highly effective biosorbent for removal of Pb from industrial wastewater prior to its discharge into the environment.

A huge volume of textile wastewater, laden with mutagenic dyes, is discharged into the environment without treatment. Among wastewater treatment strategies, biosorption is a highly effective, low cost and environment friendly process. This study aimed to evaluate the biosorption potential of non-viable biomass of Chlorella sorokiniana strain HIN-3 for various textile dyes. Firstly, the biosorption of Congo Red (direct) and Red-S3B (reactive) from water by different biosorbents was compared. Subsequently, the biosorption of seven dyes by microalgal biomass was determined. Afterward, the biosorption of dyes was measured at different temperatures (15–50°C) and biosorbent doses (0.1–2 g L−1). Biosorption kinetics were studied by pseudo-first-order (PFO), pseudo-second-order (PSO) and Elovich models. The equilibrium isotherms were studied for dye concentration of 25–500 mg L−1 using Freundlich, Langmuir and Sips models. Moreover, the microalgal biomass was characterized by fourier-transform infrared spectroscopy (FTIR), x-ray diffraction (XRD), scanning electron microscope (SEM), Brunauer–Emmett–Teller (BET) and energy dispersive spectroscopy (EDS). The algal biomass exhibited biosorption capacities of 242 and 45 mg g−1 for Congo Red and Red-S3B, respectively, surpassing plant-based biosorbents. Additionally, the microalgal biomass effectively removed other dyes; however, its biosorption capacity for the direct type of dyes was higher. The highest biosorption capacities of algal biomass for Congo Red and Red-S3B occurred with contact time of 8 h, biosorbent dose of 2 g L−1 and temperature of 40°C. The biosorption kinetics followed the PSO in case of Congo Red and PFO in the case of Red-S3B. Langmuir and Sips models best described the adsorption behavior of both the dyes. These models predicted the maximum biosorption capacity of algal biomass for Congo Red and Red-S3B to be 303 and 301 and 55.45 and 57.89 mg g−1, respectively. FTIR, SEM and BET depicted that the adsorption of the dyes by algal biomass could be attributed to the presence of various functional groups, highly porous nature and a large surface area. Thus, microalgal biomass is a highly effective biosorbent for the treatment of textile wastewater containing dyes prior to its discharge into the environment.

This study (pot experiment) investigated and compared the effectiveness of Se(VI) and Se(IV) application at a rate of 1.25 mg Se kg(-1) soil on growth, physiology, yield and As uptake by spring wheat on an uncontaminated and As-contaminated (1.5 mg kg(-1)) soil. Selenate improved wheat grain yield, relative water contents, membrane stability index, total chlorophylls, and antioxidant activities up to 43%, 18.6%, 9.5%, 16.4% and 15-46%, respectively, compared to control under As-contaminated soil. As compared to Se(IV), in accordance with above results, Se(VI) application resulted in 5-fold higher grain Se concentration and 4.4-fold higher grain Se uptake, which are partially explained by 1.3-fold higher root to grain Se translocation factor in Se(VI)-fed plants under As-contaminated soil. Concomitantly, Se(VI) offered a stronger competitive effect on As uptake thereby reducing its concentration in grains by 11% and in shoots by 44%. Translocation factor of As from root to shoots and to grains was 33% and 14.2%, respectively lesser in Se(VI)-fed plants. Thus, it is concluded that Se(VI) application, through its beneficial effects on root morphological traits, improvement in antioxidant activity and physiological behavior, is highly effective in reducing As toxicity on yield and As accumulation in wheat grains.

Climate change has been intensifying soil drying and rewetting cycles, which can alter the soil microbiome structure and activity. Here we hypothesized that a soil drying-rewetting cycle enhances biodegradation and, hence, decreases the effectiveness of nitrification inhibitors (NIs). The effectiveness of DMPP (3,4-Dimethylpyrazole phosphate) and MP + TZ (3-Methylpyrazol and Triazol) was evaluated in 60-day incubation studies under a drying and rewetting cycle relative to constant low and high soil moisture conditions (40% and 80% water-holding capacity, WHC, respectively) in two different textured soils. The measurements included (i) daily and cumulative N 2 O-N emissions, (ii) soil NH 4 + -N and NO 3 − -N concentrations, and (iii) the composition of bacterial soil communities. Application of DMPP and MP + TZ reduced the overall N 2 O-N emissions under drying-rewetting (-45%), as well as under 40% WHC (-39%) and 80% WHC (-25%). DMPP retarded nitrification and decreased N 2 O-N release from the sandy and silt loam soils, while MP + TZ mitigated N 2 O-N production only from the silt loam soil. Unexpectedly, between days 30 and 60, N 2 O-N emissions from NI-treated soils increased by up to fivefold relative to the No-NI treatment in the silt loam soil at 80% WHC. Likewise, the relative abundance of the studied nitrifying bacteria indicated that the NIs had only short-term effectiveness in the silt loam soil. These results suggested that DMPP and MP + TZ might trigger high N 2 O-N release from fine-textured soil with constant high moisture after this short-term inhibitory effect. In conclusion, DMPP and MP + TZ effectively reduce N 2 O-N emissions under soil drying and rewetting.

Inherently low concentrations of zinc (Zn), iron (Fe), iodine (I), and selenium (Se) in wheat (Triticum aestivum L.) grains represent a major cause of micronutrient malnutrition (hidden hunger) in human populations. Genetic biofortification represents a highly useful solution to this problem. However, genetic biofortification alone may not achieve desirable concentrations of micronutrients for human nutrition due to several soil- and plant-related factors. This study investigated the response of genetically biofortified high-Zn wheat genotypes to soil-applied Zn and foliarly applied Zn, I, and Se in India and Pakistan. The effect of soil-applied Zn (at the rate of 50 kg ha−1 as ZnSO4·7H2O) and foliar-applied Zn (0.5% ZnSO4·7H2O), I (0.04% KIO3), Se (0.001% Na2SeO4), and a foliar cocktail (F-CT: combination of the above foliar solutions) on the grain concentrations of Zn, I, Se, and Fe of high-Zn wheat genotypes was investigated in field experiments over 2 years. The predominantly grown local wheat cultivars in both countries were also included as check cultivars. Wheat grain yield was not influenced by the micronutrient treatments at all field locations, except one location in Pakistan where F-CT resulted in increased grain yield. Foliar-applied Zn, I, and Se each significantly enhanced the grain concentration of the respective micronutrients. Combined application of these micronutrients was almost equally effective in enhancing grain Zn, I, and Se, but with a slight reduction in grain yield. Foliar-applied Zn, Zn+I, and F-CT also enhanced grain Fe. In India, high-Zn genotypes exhibited a minor grain yield penalty as compared with the local cultivar, whereas in Pakistan, high-Zn wheat genotypes could not produce grain yield higher than the local cultivar. The study demonstrates that there is a synergism between genetic and agronomic biofortification in enrichment of grains with micronutrients. Foliar Zn spray to Zn-biofortified genotypes provided additional increments in grain Zn of more than 15 mg kg−1. Thus, combining agronomic and genetic strategies will raise grain Zn over 50 mg kg−1. A combination of fertilization practice with plant breeding is strongly recommended to maximize accumulation of micronutrients in food crops and to make significant progress toward resolving the hidden hunger problem in human populations.

Waterlogging has appeared as a major issue for agricultural production and has an adverse effect on rapeseed growth. A pot experiment was conducted to investigate the effect of soil and/or foliar applied S in alleviating the waterlogging stress in rapeseed (Brassica napus L. cv. Campino). The experiment treatments included, no soil S application (-SS), soil S fertilization (SS, 70 mg S kg−1 soil as MgSO4), foliar S application (FS, 300 ppm MgSO4) and both soil and foliar application of S (SS+FS). All the treatments were subjected to normal soil water (control) and waterlogged condition. Foliar S was applied two days prior to the onset of waterlogging treatment, which was imposed at vegetative stage (BBCH-31) for 7 days. The results demonstrated that without foliar S application, both unfertilized (-S) and S-fertilized (+S) waterlogged plants showed elevated level of hydrogen peroxide (35 % and 15 %) and malondialdehyde (84 % and 101 %) and reduced nutrients uptake, net photosynthesis and plant growth compared to their non-waterlogged counterparts. Although all S treatments alleviated the suppressing effects of waterlogging stress, the alleviative effect of soil plus foliar applied S was higher than these individual treatments. It increased dry matter by 17 %, superoxide dismutase activity by 15 %, catalase activity by 15 %, glutathione reductase activity by 14 %, ascorbate peroxidase activity by 18 %, ascorbate content by 19 %, glutathione content by 28 %. The increase in the growth and antioxidant activities of the soil plus foliar S supplemented plants was attributed to the increase in the contents of some nutrients (S 8 %, P 18 %, Mg 9 %, Zn 13 %) and net photosynthesis rate (19 %), whereas decrease in hydrogen peroxide (15 %), malondialdehyde (20 %), oxidized glutathione content (9 %), dehydroascorbic acid content (5 %) compared with untreated (without foliar-S) waterlogged plants. Collectively, the study concludes that foliar-S application supplements soil S fertilization in alleviating waterlogging stress in rapeseed plants, through inducing physiological and biochemical resistance, and improving homeostasis as well.

Reusing organic wastes in land applications would enhance the recovery of resources, following the concepts of the circular economy. The sugarcane-based sugar industry produces various by-products (e.g., sugarcane filter mud, molasses, and bagasse) that have the potential to contribute to crop production and soil fertility, owing to their high contents of organic matter and nutrients. Although the agricultural benefits of compost utilization in agriculture have been well-documented, to the best of our knowledge, few scientific data are currently available on the effects of sugarcane filter mud combined with the application of compost for increasing crop production. Thus, a field experiment was carried out to study how sugarcane filter mud, in combination with two compost sources, affected the growth and yield of sweet maize (Zea mays var. saccharata). We compared (i) two types of compost made from brassica residue and household waste applied at a rate of 9 t ha−1, and (ii) two application rates of sugarcane filter mud: 0 and 2 t ha−1 to two controls without any compost application: one with (+SFM) and one without (−SFM) sugar filter mud. The results highlighted that all crop growth and yield parameters benefited more from the domestic waste compost than from the brassica straw compost. Moreover, the addition of sugar filter mud to the compost further boosted the crop performance. Based on the above results, we concluded that the addition of sugarcane filter mud to locally available composts is a feasible approach for more sustainable production of sweet maize, combining efficient waste disposal and the provision of organic matter to the soil.

Waterlogging significantly impacts plant growth and development by altering nutrient uptake and antioxidant enzyme functions, resulting in reduced yield. Plants need sulfur (S) to produce reduced glutathione (GSH), a thiol compound that combats abiotic stresses. It is hypothesized that supplying S to high S-demanding oilseed rape plants beyond its growth requirements can reduce the adverse effect of waterlogging stress. Therefore, this study evaluated the comparative effect of different S doses (mg kg − 1 soil), i.e., no-S (S 0 ), low-S (S 1 , 35), medium-S (S 2 , 70), and high-S (S 3 , 140) on growth, yield and antioxidant defense systems of normal growing and waterlogged oilseed rape plants. Waterlogging was imposed at the inflorescence emergence stage for 7 days by retaining a 3-cm layer of water above the soil surface. Waterlogged plants supplemented with high-S showed improved growth and higher yield than those supplemented with lower S levels, and this response was associated with improved activity/contents of antioxidants, including ascorbate (AsA), GSH, ascorbate peroxidase, catalase, glutathione reductase, glutathione peroxidase, glutathione S-transferase, monodehydroascorbate reductase, and dehydroascorbate reductase, with concomitant lowering of hydrogen peroxide, dehydroascorbate and malondialdehyde content. Furthermore, leaf S concentration was enhanced in waterlogged plants treated with high-S, while anions were regulated whereby Cl − uptake was decreased. However, under control conditions, high-S did not provide additional benefits of improved plant growth, yield, and antioxidant activities compared to the medium-S application. Thus, it is concluded that additional S supplementation mitigates the adverse effects of waterlogging stress on oilseed rape, and needs to be employed as a potential strategy to alleviate the negative effects of this abiotic stress.

Owing to a competitive interaction, zinc (Zn) contained in highly Cu-contained wastewater was hypothesized to mitigate Cu toxicity-induced negative effects on the growth and quality of lettuce. Thus, growth, metal accumulation and biochemical responses of lettuce irrigated with simulated wastewater (SW, control), Cu-contaminated SW (CuSW, 20 mg Cu L−1), Zn-contaminated SW (ZnSW, 100 mg Zn L−1) and both Cu- and Zn-contaminated SW (CuZnSW, 20 mg Cu and 100 mg Zn L−1) were evaluated. Results revealed that irrigation with CuSW negatively affected growth (dry matters, root length and plant height) and quality (low mineral concentrations) of lettuce, which were associated with higher Cu uptake. Irrigation with Zn + Cu-contaminated SW retrieved Cu toxicity and improved root and shoot dry matters and root length by 13.5