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Being a primary toxic heavy metal, lead (Pb) contamination presents an imposing environmental and public health concern worldwide. A Bacillus subtilis PbRB3, displaying higher Pb tolerance, was isolated from the textile effluent. The bacterial culture was able to remove >80% of Pb from culture solution. Upon screening in the presence of Pb, PbRB3 strain exhibited significant plant growth promoting potential. A 3 weeks long pot experiment was established to examine the capability of PbRB3 strain for physiological and biochemical traits, and Pb accumulation tendency of mung bean at 250 and 500 mg kg−1 of Pb toxicity, respectively. With respect to control treatments, photosynthetic pigments, protein synthesis, net assimilation rate, transpiration rate and stomatal conductance were significantly constrained by Pb toxicity levels. Intrinsic and instantaneous water use efficiencies were considerably improved in inoculated plants under Pb toxicity. Compared to inoculated control, significantly higher superoxide dismutase activity in both Pb toxicity treatments, while higher malondialdehyde contents only at Pb500 treatment was recorded with PbRB3 inoculation. Catalase activity between Pb250 and Pb500 treatments was comparable at both inoculation level. Moreover, PbRB3 inoculation led to significantly higher peroxidase activity under Pb toxicity treatments compared to inoculated control. The PbRB3 inoculation led to comparable differences in root Pb content between Pb250 and Pb500 treatments. These results suggest that inoculation of Pb tolerant, Bacillus subtilis PbRB3, could be employed to improve mung bean growth potential and adaptation against Pb toxicity, and thereby accelerated Pb rhizoaccumulation from metal contaminated environment. • A Bacillus subtilis PbRB3 was isolated from textile effluent. • PbRB3 removed >80% of Pb from spiked culture solution. • Photosynthetic pigments impaired by Pb toxicity even upon inoculation. • PbRB3 improved plant water use efficiency at Pb250 and Pb500. • PbRB3 mediated Pb translocation from root to aerial part. [ABSTRACT FROM AUTHOR]

Excessive use of nitrogenous fertilizers and their improper management in agriculture causes nitrate contamination of surface and groundwater resources. This study was conducted along the seasonally flooded alluvial agricultural area of Indus River Basin to determine the spatial and temporal dynamics of nitrate concentrations in the groundwater along the river. Total of 112 samples were collected from shallow (30–40 ft) and deep groundwater (120–150 ft) wells at seven sites, 25 km apart from each other and covered an area of 170 km along the river, during four sampling campaigns between October 2016 to May 2017 i.e. in start, mid and end of dry season. The study period covered the whole agricultural cycle including the wet summer season with no agricultural activities under flooding and the sampling sites were always less than 2 km from the river bank. Nitrate concentrations of shallow wells were 15–54 and 20–45 mg L−1 during the start and middle of dry season, respectively. However, at the end of the dry season, the highest nitrate concentrations of 35–75 mg L−1 were recorded and 70% of these samples contained nitrate concentrations above the permissible limit 50 mg L−1. Similar seasonal patterns of nitrate concentrations were observed in deep wells, however, δ18O data suggested lower recharge in deep well than shallow wells. The results illustrated that high nitrate concentrations in shallow wells were associated with high δ18O values indicating that the quantity of evaporated water infiltrated from the floodplain, possibly from distribution channels, along with the nitrate polluting shallow wells more than the deep wells. At the end of the dry season, nitrate concentrations exceeded the permissible limits in both shallow and deep wells, which possibly happened due to the horizontal movement of groundwater along with the nitrate mixing during vertical seepage of river water to the aquifers. Image 1 • Patterns of nitrate in groundwater along the Indus River Basin (IRB) were studied. • Shallow wells had higher nitrate concentrations than deep wells. • Nitrate concentrations of 70% samples were 35–75 mg L−1 after flooding. • δ18O values showed strong flooding effects on groundwater nitrate concentrations. [ABSTRACT FROM AUTHOR]

A field study was conducted to test the potential of 5-year consecutive application of fresh industrial sludge (FIS) and composted industrial sludge (CIS) to restore soil functions at surface (0–15 cm) and subsurface (15–30 cm) of the degraded agricultural land. Sludge amendments increased soil fertility parameters including total organic carbon (TOC), soil available nitrogen (SAN), soil available phosphorus (SAP) and soil available potassium (SAK) at 0–15 cm depth. Soil enzyme activities i.e. dehydrogenase (DHA), β-glucosidase (BGA) and alkaline phosphatase (ALp) were significantly enhanced by FIS and CIS amendments in surface soil. However, urease activity (UA) and acid phosphatase (ACp) were significantly reduced compared to control soil. The results showed that sludge amendments significantly increased microbial biomass nitrogen (MBN) and microbial biomass phosphorus (MBP) at both soil depth, and soil microbial biomass carbon (MBC) only at 0–15 cm depth. Significant changes were also observed in the population of soil culturable microflora (bacteria, fungi and actinomycetes) with CIS amendment in surface soil suggesting persistence of microbial activity owing to the addition of organic matter source. Sludge amendments significantly reduced soil heavy metal concentrations at 0–15 cm depth, and the effect was more pronounced with CIS compared to unamended control soil. Sludge amendments generally had no significant impact on soil heavy metal concentrations in subsoil. Agronomic viability test involving maize was performed to evaluate phytotoxicity of soil solution extract at surface and sub-surface soil. Maize seeds grown in solution extract (0–15 cm) from sludge treated soil showed a significant increase of relative seed germination (RSG), relative root growth (RRG) and germination index (GI). These results suggested that both sludge amendments significantly improved soil properties, however, the CIS amendment was relatively more effective in restoring soil functions and effectively immobilizing wastewater derived heavy metals compared to FIS treatment. [ABSTRACT FROM AUTHOR]

The environmental and economic impacts of chemical fertilizer have encouraged farmers to integrate them with organic materials, an important nutrient management strategy for sustainable agriculture production. In the present study, we conducted field experiments to study the effects of nitrogen enriched compost (NEC) and mineral nitrogen (MN) fertilizer with a selected plant growth promoting rhizobacterial (PGPR) strain, Pseudomonas aeruginosa QS40, on productivity of sunflower and soil fertility. The results demonstrated that integrated application of PGPR with organic-inorganic N significantly increased shoot and root length, leaf area, total chlorophyll, head diameter, fresh biomass, straw-achene yield and N uptake in sunflower compared to unamended control and PGPR alone. The results also showed that integrated N biofertilizer regime enhanced soil microbial biomass, enzymatic activities and soil nitrogen contents. We also observed significant changes in rhizosphere soil pH, abundance of cultivable bacteria and arbuscular mycorrhizae fungi (AMF) root colonization. Treatment and year interaction was significant for dissolved organic carbon (DOC) and microbial biomass carbon (MBC) only. These results suggest that the efficiency of PGPR could be improved with increased availability of labile C substrate resource in NEC amended aridisol. We conclude that the application of NEC fertilizer with efficient PGPR biofertilizer may improve sunflower productivity and soil chemical and biological fertility in nutrient-poor agroecosystems of arid and semi-arid regions. [ABSTRACT FROM AUTHOR]

• Pakistan is only contributing 0.9% to global greenhouse gas (GHG) emissions and is facing devastating floods. • Every governments must turn and listen to science urgently. • The NASA, NSF, and USDA should provide funding to the developing countries for better climate change predictions. [ABSTRACT FROM AUTHOR]

Abstract: Eighteen rhizobacterial isolates, with ACC deaminase activity, were screened for their growth promoting activity in maize under axenic conditions. Out of these, two strains Pseudomonas thivervalensis (STF3) and Serratia marcesens (STJ5), demonstrating maximum growth promotion effect, were characterized and used in the field experiments. The classical triple response assay supported the involvement of ACC deaminase in growth promotion. Selected rhizobacterial strains were investigated for their growth and yield promoting potential under field conditions with 50, 75 and 100% recommended chemical fertilizers (CF). Results of the study revealed that the rhizobacterial isolates, with 75 and 100% CF, significantly improved the growth and yield of maize compared to the uninoculated control treatment. The growth and yield promoting effect of rhizobacterial strain P. thivervalensis (STF3) with 75% CF were similar to that of CF alone. However, with 100% CF, same rhizobacterial strain significantly increased plant height, total biomass, grain yield, 1000-grain weight and chlorophyll content compared to the uninoculated control. Varied ACC deaminase activity might be responsible for differential behavior of P. thivervalensis (STF3) and S. marcesens (STJ5) under axenic and filed conditions. However, the selected rhizobacterial isolates differed markedly for presence of multifarious growth promoting characteristics which may also partly explain the variations in their efficiency to promote growth and yield of maize. [Copyright &y& Elsevier]

Pollution from potentially toxic metals (PTMs) is one of the most pressing global environmental challenge with soaring human health concerns. It is now critical to seek out effective remediation technologies to control PTMs in the terrestrial environment. Biochar has piqued the interest of researchers due to its ability to immobilize PTMs, particularly in soil, with the assumption that biochar having unique physico-chemical properties may influence PTM mobility. A meta-analysis was performed using 1503 observations extracted from 80 peer-reviewed articles to determine: (a) the effects of various physico-chemical properties of biochar on the bioavailability of PTMs (As, Cd, Cu, Ni, Pb, Zn) in soil and plants, and (b) the best specification of physico-chemical properties of biochar for effective remediation of these PTMs. The findings revealed that the reduction rate of PTM bioavailability is heavily influenced by the physico-chemical properties of both biochar and soil. The physico-chemical parameters of biochar that have effective response to PTMs immobilization were as; 101–500 m2 g−1 surface area, neutral to alkaline pH, pyrolysis temperature > 500 °C, with best application rate of 1.1–3%. However, overall results indicate that the biochar, with given specification of physico-chemical attributes, can decrease the bioavailability of PTMs by 40% in soil and 22% in plants. Moreover, edaphic factors such as soil pH, texture, and crop type can also influence the biochar mediated PTMs adsorption and transformation under field or pot conditions. Furthermore, research gaps remain to be filled in order to investigate the efficiency, high specificity, and secondary pollution aspects of biochar, particularly on large-scale applications as an amendment for PTM remediation. [Display omitted] • Eighty peer reviewed publications were used to conduct this meta-analysis. • Biochar addition can reduce PTMs concentration in soil by 40% and in plants by 22%. • Biochar pyrolyzed at >500 °C with 101–500 m2 g−1 surface area showed effective results. • Immobilization of PTMs can be a function of physicochemical properties of biochar. • Criteria should be established for uniform classification of biochar. [ABSTRACT FROM AUTHOR]

The production and soil accumulation of nanoparticles (NPs) from the industrial sector has increased concerns about their toxic effects in plants which needs the research to explore the ways of reducing NPs toxicity in pants. The gibberellic acid (GA) has been found to reduce abiotic stresses in plants. However, the effect of GA in reducing zinc oxide (ZnO) NPs-mediated toxicity in plants remains unclear. In this study, foliar application of GA was used to explore the possible role in reducing ZnO NPs toxicity in wheat (Triticum aestivum L.) plants. The plants were grown in pots spiked with ZnO NPs (0, 300, 600, 900, 1200 mg/kg) and GA (0, 100, 200 mg/L) was foliar sprayed at different times during the growth period under ambient environmental conditions. Our results demonstrated that GA inhibited the toxicity of ZnO NPs in wheat especially at higher levels of NPs. The GA application improved the plant biomass, photosynthesis, nutrients, and yield under ZnO NPs stress. The GA reduced the Zn accumulation, and reactive oxygen species generation in plants caused by toxicity of NPs. The protective effect of GA in decreasing ZnO NPs-induced oxidative stress was related to GA-mediated enhancement in antioxidant enzymes in plants. The role of GA in enhancing tolerance of wheat against ZnO NPs was further confirmed by the enhancement in nutrient contents in shoots and roots of wheat. Overall, our study provides the evidence that GA can reduce ZnO NPs-induced toxicity in wheat and probably in other crops which needs further in-depth investigation. Image 1 • Gibberellic acid (GA) can alleviate ZnO NPs-induced growth inhibition of wheat. • GA increased the chlorophyll contents in wheat under ZnO NPs stress. • GA increased P, K, Fe and Mn and decreased Zn concentrations in wheat under ZnO NPs stress. • GA alleviates ZnO NPs-induced oxidative stress by mediating antioxidant system in wheat. Gibberellic acid alleviated the zinc oxide nanoparticles-induced toxicity in wheat by enhancing biomass, photosynthesis and by reducing oxidative stress in plants. [ABSTRACT FROM AUTHOR]

Salinity stress is one of the major environmental stresses that impose global socio-economic impacts, as well as hindering crop productivity. Halotolerant plant growth-promoting rhizobacteria (PGPR) having potential to cope with salinity stress can be employed to counter this issue in eco-friendly way. In the present investigation, halotolerant PGPR strains, AP6 and PB5, were isolated from saline soil and characterized for their biochemical, molecular and physiological traits. Sequencing of 16 S rRNA gene and comparative analysis confirmed the taxonomic affiliation of AP6 with Bacillus licheniformis and PB5 with Pseudomonas plecoglossicida. The study was carried out in pots with different levels of induced soil salinity viz. 0, 5, 10 and 15 dSm−1 to evaluate the potential of bacterial inoculants in counteracting salinity stress in sunflower at different plant growth stages (30, 45 and 60 days after sowing). Both the bacterial inoculants were capable of producing indole acetic acid and biofilm, solubilizing inorganic rock phosphate, and also expressed ACC deaminase activity. The PGPR inoculated plants showed significantly higher fresh and dry biomass, plant height, root length and yield plant−1. Ameliorative significance of applied bacterial inoculants was also evidenced by mitigating oxidative stress through upregulation of catalase (CAT), superoxide dismutase (SOD) and guaiacol peroxidase (GPX) antioxidant enzymes. Increase in photosynthetic pigments, gas exchange activities and nutrient uptake are crucial salt stress adaptations, which were enhanced with the inoculation of salt tolerant biofilm producing PGPR in sunflower plants. Although increase in salinity stress levels has gradually decreased the plant's output compared to non-salinized plants, the plants inoculated with PGPR confronted salinity stress in much better way than uninoculated plants. Owing to the wide action spectrum of these bacterial inoculants, it was concluded that these biofilm PGPR could serve as effective bioinoculants and salinity stress alleviator for sunflower (oil seed crop) by increasing crop productivity in marginalized agricultural systems. Image 1 • Biofilm forming PGPR inoculant approach was developed to improve sunflower salt tolerance. • Biofilm PGPR solubilized P, secreted IAA, and expressed ACC-deaminase activity. • PGPR mediated salt tolerance in sunflower was evident by oxidative stress reduction. • Plant physiological and biochemical functions at highest salinity level were improved by biofilm bacteria. • Biofilm PGPR could be an appealing option to improve productivity of salt affected soil. [ABSTRACT FROM AUTHOR]

Heavy metal contamination of agricultural soil has become a serious global problem. This study was aimed to evaluate the effects of two chromium (Cr) tolerant plant growth promoting bacteria (PGPB) in combination with salicylic acid (SA) on plant growth, physiological, biochemical responses and heavy metal uptake under Cr contamination. A pot experiment (autoclaved sand as growing medium) was performed using maize ( Zea mays L.) as a test crop under controlled conditions. Cr toxicity significantly reduced plant growth, photosynthetic pigment, carbohydrates metabolism and increased H 2 O 2 , MDA, relative membrane permeability, proline and Cr contents in maize leaves. However, inoculation with selected PGPB ( T2Cr and CrP450 ) and SA application either alone or in combination alleviated the Cr toxicity and promoted plant growth by decreasing Cr accumulation, H 2 O 2 and MDA level in maize. Furthermore, dual PGPB inoculation with SA application also improved plant performance under Cr-toxicity. Results obtained from this study indicate that PGPB inoculation and SA application enhanced Cr tolerance in maize seedlings by decreasing Cr uptake from root to shoot. Additionally, combination of both PGPB and SA also reduced oxidative stress by elevating the activities of enzymatic and non-enzymatic antioxidant, also indicated by improved carbohydrate metabolism in maize plant exposed to Cr contamination. Comparatively, alleviation effects were more pronounced in PGPB inoculated plants than SA applied plants alone. The results suggest that combined use of PGPB and SA application may be exploited for improving production potential of maize in metal (Cr) contaminated soil. [ABSTRACT FROM AUTHOR]

[Display omitted] • A global meta-analysis of nitrogen inhibitors to reduce N 2 O emissions across agro-system. • Overall, DCD and DMPP mitigated N 2 O emissions by 47% and 39%, respectively. • Relative efficacy of DCD was higher in chemically fertilized and acidic soils. • DCD is the exclusive option for vegetable fields, while DMPP is more suitable for maize fields. The production of biofuels from crop biomass is now seen as a practical renewable energy alternative, reducing overdependence on fossil fuels and limiting global warming from greenhouse gases. With respect to nitrogen emissions from biomass, it is claimed that nitrification inhibitors (NIs), particularly dicyandiamide (DCD) and 3,4-dimethylpyrazole phosphate (DMPP), can reduce these nitrogen losses. Nevertheless, the effectiveness of these NIs to reduce N 2 O emissions and NH 3 volatilization under different environmental conditions remains largely unclear. To this aim, a global meta-analysis was performed using 366 observations from 149 peer-reviewed research studies to quantify the responses of N 2 O emissions and NH 3 volatilization to the application of DCD and DMPP under different conditions. Based on the meta-analysis, DCD and DMPP can significantly reduce N 2 O emissions by 47% and 39%, respectively. The efficiency of DCD in reducing N 2 O emissions was much higher (12%) than that of DMPP when used together with chemical fertilizers. Interestingly, DCD tended to be more effective (9–10%) in incubation and field trials , while DMPP showed 39% higher efficacy. Concerning NH 3 , fertilizer-type, and soil pH, specific effects of NIs were not significant overall. Although DCD (pot experiments) and DMPP (incubation experiments) showed 30% and 46% higher NH 3 emissions, respectively, their effects were not significant under field conditions. According to meta-analysis, DCD and DMPP have demonstrated great potential to reduce N 2 O emissions. Importantly, the efficacy of such eco-friendly interventions could further be improved if the preferences described above are followed. Therefore, it will take further investigation to understand the mechanisms underlying the relatively higher efficacy of one NI over the other under specific conditions, including crop type, the nature of experiment, and other edaphic factors. [ABSTRACT FROM AUTHOR]

A long-term energy crisis has resulted in increased combustion of biomass fuel in industrial and household sectors in Pakistan. We report results of a study on the emission characteristics of rice husk, rice straw, corncobs and bagasse since they are frequently used as biomass fuel and differed remarkably in physico-chemical and combustion characteristics. Emission concentrations and emission factors were determined experimentally by burning the biomass fuel using a burning tower. Modified combustion efficiency (MCE) of rice husk, rice straw, corncobs and bagasse was >0.97 indicating that combustion was dominated by flaming mode. Emission factors of gaseous pollutants CO, CO2, NO2, NO, NO x and SO2 for rice straw were calculated to be 17.19 ± 0.28, 1090.07 ± 24.0, 0.89 ± 0.03, 1.48 ± 0.04, 3.16 ± 0.08 and 0.38 ± 0.03 g kg−1 respectively which were significantly (p < 0.05) higher compared to those from rice husk (14.05 ± 0.18, 880.48 ± 8.99, 0.19 ± 0.01, 1.38 ± 0.02, 2.31 ± 0.04 and 0.11 ± 0.03 g kg−1), corncobs (8.63 ± 0.12, 595.44 ± 10.38, 0.16 ± 0.01, 0.70 ± 0.01, 1.23 ± 0.02 and 0.02 ± 0.00 g kg−1) and bagasse (12.39 ± 0.08, 937.03 ± 9.07, 0.36 ± 0.03, 1.44 ± 0.02, 2.57 ± 0.04 and 0.18 ± 0.02 g kg−1). Total emissions of CO, CO2, NO2, NO, NO x and SO2 were estimated to be 3.68, 230.51, 0.05, 0.36, 0.60 and 0.03 Gg for rice husk, 33.75, 2140.35, 1.75, 2.91, 6.20 and 0.75 Gg for rice straw, 1.11, 76.28, 0.02, 0.02 and 0.03 Gg for corncobs and 42.12, 3185.53, 1.22, 4.90, 8.74 and 0.61 Gg for bagasse respectively. Rice straw, however, had significantly (p < 0.05) higher potential of gaseous pollutant emission factors. Bagasse had the highest values of total emissions followed by rice straw, rice husk and corncobs. Rice straw and bagasse, on cumulative basis, contributed more than 90% of total emissions of gaseous pollutants. Results reported in this study are important in formulating provincial and regional emission budgets of gaseous pollutants from burning of agricultural residues in Pakistan. [ABSTRACT FROM AUTHOR]

Soil salinity is one of the most pernicious environmental hazards affecting crop growth and productivity in arid and semi-arid climates. In saline soils, the crop plants encounter nutrients deficient conditions mainly due to antagonistic affinity of sodium (Na+) and chloride (Cl−). The accumulation of salts in the rhizosphere restricts plant growth, the severity of which depends on the source and concentration of the salt. Therefore, we hypothesized that sodium containing salts could have toxic effects on maize plants either in a single or in combined form. To evaluate the interactive effect of sodium salts on plant growth, ionic homeostasis, and seed quality attributes, a pot study was performed using maize as a test plant at the research area of the College of Agriculture, University of Sargodha. Selected salts including, NaCl, Na 2 SO 4 and their combination (NaCl + Na 2 SO 4), were applied in equal ratio for different salinity levels (7, 10, 13 and 16 dS m−1) and the untreated control. The results show that all the measured growth, yield, biochemical and quality attributes of maize were negatively affected with increasing concentration of all the salt sources; however, severity of these effects were more intense when NaCl was applied at all salinity levels. It is concluded that all salts (NaCl, Na 2 SO 4 and NaCl + Na 2 SO 4) had negative effects on biochemical, qualitative, growth and yield characteristics of maize plant. Most importantly, NaCl was found to be more harmful compared to Na 2 SO 4 and mixtures of both salts due to the dominance of Na+ and Cl-ions. Among all salinity levels, the more detrimental effects of NaCl occurred at salinity level of 16 dS m−1. [Display omitted] • A pot study was established for evaluation of salinity sources and their formulations at different levels. • Higher salinity increased the Na: K ratio in maize tissues, and caused reduction in yield. • NaCl was more toxic than Na 2 SO 4 for maize and mixture of both at all salinity levels. [ABSTRACT FROM AUTHOR]

Being analogue to arsenic (As), phosphorus (P) may affect As dynamics in soil and toxicity to plants depending upon many soil and plant factors. Two sets of experiments were conducted to determine the effect of P on As fractionation in soils, its accumulation by plants and subsequent impact on growth, yield and physiological characteristics of sunflower (Helianthus annuus L.). Experimental plan comprised of two As levels (60 and 120 mg As kg−1 soil), four P (0-5-10-20 g phosphate rock kg−1 soil) and three textural types (sandy, loamy and clayey) with three replications. Among different As fractions determined, labile, calcium-bound, organic matter-bound and residual As increased while iron-bound and aluminum-bound As decreased with increasing P in all the three textural types. Labile-As percentage increased in the presence of P by 16.9–48.0% at As60 while 36.0–68.1% at As120 in sandy, 19.1–64.0% at As60 while 11.5–52.3% at As120 in loamy, and 21.8–58.2% at As60 while 22.3–70.0% at As120 in clayey soil compared to respective As treatment without P. Arsenic accumulation in plant tissues at both contamination levels declined with P addition as evidenced by lower bioconcentration factor. Phosphorus mitigated the As-induced oxidative stress expressed in term of reduced hydrogen peroxide, malondialdehyde while increased glutathione, and consequently improved the achene yield. Although, P increased As solubility in soil but restricted its translocation to plant, leading to reversal of oxidative damage, and improved sunflower growth and yield in all the three soil textural types, more profound effect at highest P level and in sandy texture. [Display omitted] • Arsenic can have serious repercussions both for human and animal health by compromising the soil, water and food quality. • Phosphorus could alter As fractions in soils, an increase in L-As, Ca–As, OM-As and R–As while decrease in Fe–As and Al–As. • Arsenic-induced oxidative stress in term of H 2 O 2 and MDA could efficiently be ameliorated with P in sunflower. • Phosphorus could increase As solubility and mobility in soil, but restricted its accumulation in plant tissues. Ameliorative effects of P against As toxicity in sunflower were more profound at highest P level and in sandy texture. P had a marked effect on As fractionation in all the three textured soils but the effect was highest at elevated P level, and in sandy soil. P-induced resistance to As toxicity was associated with an inhibition in As accumulation, and protection against oxidative stress by activating the antioxidant system. [ABSTRACT FROM AUTHOR]

Micro- and nano-plastics have widely been recognized as major global environmental problem due to its widespread use and inadequate waste management. The emergence of these plastic pollutants in agroecosystem is a legitimate ecotoxicological concerns for food web exchanges. In agriculture, micro/nano plastics are originated from a variety of different agricultural management practices, such as the use of compost, sewage sludge and mulching. A range of soil properties and plant traits are affected by their presence. With the increase of plastic debris, these pollutant materials have now begun to demonstrate serious implications for key soil ecosystem functions, such as soil microbial activity and nutrient cycling. Nitrogen (N) cycle is key predictor of ecological stability and management in terrestrial ecosystem. In this review, we evaluate ecological risks associated with micro-nano plastic for soil-plant system. We also discuss the consequence of plastic pollutants, either positive or negative, on soil microbial activities. In addition, we systematically summarize both direct and hypothesized implications for N cycling in agroecosystem. We conclude that soil N transformation had showed varied effects resulting from different types and sizes of plastic polymers present in soil. While mixed effects of microplastic pollution on plant growth and yield have been observed, biodegradable plastics have appeared to pose greater risk for plant growth compared to chemical plastic polymers. Image 1 • Micro and nano-plastic sourced from a variety of agricultural practices. • Micro and nano-plastic can alter soil N biogeochemistry. • Micro and nano-plastic effects on crop are inevitable. • Nano-plastic may ends up in human/animal body. [ABSTRACT FROM AUTHOR]