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Heavy metals occur naturally in very small amounts in living organisms, but exposure to their higher concentrations is hazardous. Heavy metals at hazardous levels are commonly found in foodstuffs of Bangladesh, mainly due to the lack of safety guidelines and poor management of industrial effluents. Several lines of evidence suggest that the level of heavy metals in foodstuffs of Bangladesh is higher than the acceptable limits set by World Health Organization/Food and Agriculture Organization. Literature survey revealed that the sources and transport pathways of heavy metals in the ecosystem and the abundance of heavy metals in the food products of Bangladesh are potential threats to food safety. However, an extensive assessment of the toxicity of heavy metals in food webs is lacking. Although widespread heavy metal contamination in various foodstuffs and environmental matrices have been summarized in some reports, a critical evaluation regarding multi-trophic transfer and the health risk of heavy metal exposure through food chain toxicity in Bangladesh has not been performed. This systematic review critically discussed heavy metal contamination, exposure toxicity, research gaps, existing legislation, and sustainable remediation strategies to enhance Bangladesh's food safety. In particular, this study for the first time explored the potential multi-trophic transfer of heavy metals via food webs in Bangladesh. Furthermore, we recommended a conceptual policy framework to combat heavy metal contaminations in Bangladesh.

Salinity is abiotic stress, which causes adverse environmental conditions for rice cultivation. In particular, local aromatic rice cultivation is heavily influenced by soil salinity stress, which has an impact on global food security. This study aimed to screen local aromatic rice genotypes in a hydroponics experiment using Yoshida solutions to evaluate the effect of increasing NaCl concentrations on the early growth stages of rice seedlings. Genetic diversity along with phylogenetic relationship was assessed using the random amplified polymorphic DNA (RAPD) markers. Out of 20 RAPD markers, 17 markers produced reproducible polymorphic bands. Individuals of all genotypes shared 88 (89.80%) of the 98 total RAPD elements amplified. The genetic distance-focused similarity index ranged from 0.05 to 0.94. The highest genetic distance (0.94) was discovered between genotypes Nayanmoni and Kalijira Barisal, and the lowest was between Badshabhog and Kataribhog (0.05). In addition, the OPS 3(510bp) and OPA 14(1100bp) markers could be used to identify salt-tolerant genotypes. According to genetic distance, the salt stress tolerant check genotype, Pokkali was genetically related to Chinigura as well as Kalijira Barisal. This study established a simple and consistent method for evaluating variability across various aromatic rice genotypes, which will benefit in genotype selection for breeding salinity stress tolerant aromatic rice varieties in Bangladesh.

Soil salinity has emerged as a serious issue for food security due to global climate change. It is estimated that currently about 62 million hectares or 20 percent of the world’s irrigated land is affected by salinity. Salinity is a serious problem in the coastal areas of Bangladesh. Isolation of salt-tolerant plant growth-promoting bacteria (PGPB) and applying them as bioinoculants in crop plants are considered promising and effective biotechnological approaches to combat soil salinity. This study aimed to screen salt-tolerant PGPB from the root, leaf, and rhizospheric soils of rice plants collected from salt-affected coastal areas including Chattogram, Noakhali, Lakshmipur, and Cox’s Bazar districts of Bangladesh and evaluated their performances on the seedling growth of rice. Out of forty-one salinity-tolerant bacterial isolates screened, Brevibacterium sediminis showed salinity tolerance up to 12% NaCl (w/v). In vitro bioassay revealed that B. sediminis promoted the seedling growth of rice cv. BRRI dhan29 (salinity susceptible) and BINAdhan-10 (salinity tolerant), and the growth-promoting effects were higher in BINAdhan-10. This study for the first time identified B. sediminis strain IBGE3C as a salt-tolerant PGPB from a widely cultivated rice variety, BRRI dhan28 in the Lakshmipur district of Bangladesh. Our results suggest that salt-tolerant PGPB isolated from the root, leaf, and rhizospheric soil of rice plants could be used as a low cost and environmentally friendly option for overcoming the detrimental effects of salt stress on rice plants in the southern coastal regions of Bangladesh. However, further studies are needed for assessing the efficacy of B. sediminis on enhancement of salinity tolerance, and growth and yield of rice under salinity stressed conditions.

This study involved analysis and method validation of spirotetramat applied to two phenotypically different Korean vegetables (e.g. Korean cabbage and shallots) to determine the safe pre-harvest residue limit (PHRL) and comparative dissipation patterns. Two steps of the investigation involved greenhouse monitoring during crop cultivation followed by LC-MS/MS analysis. Commercial spirotetramat was sprayed twice with seven-day intervals according to the spray schedule (0, 3, 7, 10, 14, and 21 days before harvest) at the dose recommended by the Ministry of Food and Drug Safety (MFDS), Korea. During the validation of the analytical method, good linearity, specificity, and acceptable recoveries (82%–114% for Korean cabbage and 82%–111% for shallot) were established for spirotetramat and its four metabolites. The calculated biological half-life derived from the first-order reaction (t1/2) of spirotetramat was 4.8 days for Korean cabbage and 4.0 days for shallot, respectively. The safe PHRL for Korean cabbage was suggested at 7 days, due to permissible spirotetramat concentration in terms of an acceptable MRL. The findings of the study will be used as the analytical reference point for developing spirotetramat safety guidelines for use in the vegetables investigated.

Conservation tillage (CA) is an option for maintaining soil health and the surrounding environment for intensive agriculture, especially on the tropical climate. A three years lengthy research experiment was performed in arid climate from 2014 to 2016 at Bangladesh Agricultural Research Institute (BARI) to evaluate the effect of conservation tillage approaches on environmental sustainability and water productivity of irrigated maize cultivation. The conservation tillage practices (Zero tillage-ZT and Minimum tillage-MT) are evaluated in comparison to the traditional farmer’s practices. Amongst these, the treatment combination having MT with optimum irrigation best suits for cost-effective sustainable technique in maize cultivation without compromising with the yield at the dry season in the red brown terrace soil of Bangladesh. This combination of CA treatment is environment-friendly for maize cultivation as the treatment combination consumes the lowest amount of fuel (29.70 L/ha) for tilling purposes and required fewer water resources (only 2 time irrigation) for irrigation purposes and thus reduces the amount of carbon dioxide and other emitted toxic gaseous molecules to the surrounding environment. Therefore, MT with optimum irrigation is evaluated as the best options for continuous maize cultivation in the red brown terrace soil without any yield penalty.

Genetic variability, heritability, genetic advance, correlation coefficient analysis, path coefficient analysis and genetic divergence between yield and its contributing traits were estimated using fifteen (15) different chilli genotypes in northern region of Bangladesh. The aim of this study is to screen out suitable parents for next hybridization program. The phenotypic coefficient of variations was found slightly higher than the genotypic coefficient of variations for all characters studied, indicating that the apparent variation is not only genetic but also influenced by the growing environment in the expression of the traits. High genotypic and phenotypic coefficient of variation was observed in length of fruit (27.27% and 27.81%). High heritability coupled with high genetic advance in percent of mean in fruit yield per plant (71.23 and 39.38), number of fruits per plant (71.26 and 31.18), weight of individual fruit (88.52 and 43.80), length of fruit (96.13 and 70.59) and diameter of fruit (79.58 and 35.79) suggested that these characters would be considered for varietal selection. The correlation studies revealed that fruit yield per plant showed significant positive correlation with plant height (0.369), number of fruits per plant (0.587), weight of individual fruit (0.634) and length of fruit (0.450) which can be considered for selection of a good variety. Path analysis revealed weight of individual fruit (0.293), plant height (0.205), number of branches per plant (0.186), length of fruit (0.164), number of fruits per plant (0.132) and diameter of fruit (0.078) had direct positive effect on yield per plant, indicating these traits are the main contributors to fruit yield per plant. The divergence value for cluster analysis showed the highest inter-cluster distance between clusters II and IV which indicates that these genotypes may provide high heterosis in hybridization and expected to show wide variability in genetic architecture.

The coastal zone of Bangladesh, with a population density of 1278 people per square kilometer, is under serious threat due to heavy metal pollution. To date, many studies have been conducted on the heavy metal contamination in soils, water, aquatic animals, and plants in the coastal zone of Bangladesh; however, the available information is dispersed. In this study, previous findings on the contamination levels, distributions, risks, and sources of heavy metals in sediments and organisms were summarized for the first time to present the overall status of heavy metal pollution along coastal regions. Earlier research found that the concentrations of various heavy metals (HMs), particularly Co, Cd, Pb, Cu, Cr, Mn, Fe, and Ni in water, sediment, and fish in most coastal locations, were above their permissible limits. High concentrations of HMs were observed in sediments and water, like Cr of 55 mg/kg and 86.93 mg/l in the ship-breaking areas and Karnaphuli River, respectively, in coastal regions of Bangladesh. Heavy metals severely contaminated the Karnaphuli River estuary and ship-breaking area on the Sitakundu coast, where sediments were the ultimate sink of high concentrations of metals. Sedentary or bottom-dwelling organisms like gastropods and shrimp had higher levels of heavy metals than other organisms. As a result, the modified PRISMA review method was used to look at the critical research gap about heavy metal pollution in Bangladesh's coastal areas by analyzing the current research trends and bottlenecks.

Citrus fruits are extensively cultivated, consumed and major processed horticulture crops around the globe. High processing and consumption generate huge quantities of solid organic wastes. Citrus waste represents approximately 40-50% of total fruit weight, which consists of rag (membranes and cores), pulp, seeds, and peel (albedo and flavedo), which are a potential source of value-added products including essential oils, carotenoids, pectin, dietary fibers, and polyphenols biofuel, etc. However, waste produced is discarded as waste in the environment, which causes a serious threat due to the presence of bioactive compounds. Recent research strategies on the integrated biorefinery approach explore various ways to utilize the waste obtained from the citrus wastes for their subsequent recovery of value-added products. Moreover, the citrus waste can be turned into various bio-products, viz., enzymes, biofuels, and biopolymers using the integrated biorefinery approach, which can optimize the development of green waste for sustainability and economic benefits. Given the sustainable solution for resource recovery and environmental management, the article reviews the latest advances in the novel valorization approach and valuation of the existing state-of-the-art green technologies for citrus waste utilization to bring a sustainable solution for increasing demand for food, fuel, and energy security. To achieve the zero-waste approach and industrial viability, more efforts should be given to scale-up green recovery techniques along with diverse product profiling.

A quantitative assessment was attempted to determine concentrations of total arsenic (As) in farmer's field soils and fruits of brinjal collected from two famous brinjals producing Upazila's, namely Melandaha and Islampur of Jamalpur district, Bangladesh. The study also evaluated cancer and non-cancer health risks for both males and females caused by dermal exposure of soils and dietary intake of brinjal grown in farmers' fields and sold at different markets of four country districts. The study findings revealed that 75% of soil sampling locations had enrichment factor (EFc) values 1.5, indicating the anthropogenic sources of As, and 50% of the sites possessed EFc values within the range of 2.0-5.0 indicated moderate enrichment of As. The mean concentrations of As in brinjal grown in farmers' fields and retailers of different markets of four districts were 0.18 and 0.39 µg g

Food waste management is a critical environmental issue in many developing countries, including Bangladesh, due to unplanned food waste disposal and lack of dedicated food waste legislation. In those countries, a significant amount of food waste is discarded to the environment rather than being recycled. In Bangladesh, food waste is traditionally often used for composting, landfilling, and feeding animals, as there is no valorization option. In addition, food waste and food waste streams of food industries are utilized for the recycling and production of diverse economically valuable bioactive compounds. Therefore, we conducted a detailed literature review on food waste management and valorization options in Bangladesh and discussed the findings in the context of global status. The amount of food waste in Bangladesh is quite high, and it needs to be recycled to promote the circular economy of this developing nation. In this study, it is revealed that various research uncertainties and gaps regarding sustainable food waste management exist in Bangladesh, which should be investigated as priority research. Furthermore, a logical and global synchronization of the contemporary approach to food waste valorization with policy advocacy is proposed, to ensure efficient food waste decontamination and recycling in Bangladesh. This is the first and most comprehensive evaluation of the present research trend and prospects for sustainable recycling of food waste for the circular economy of Bangladesh.

The impact of stress on crop productivity and the ecosystem have been magnified by climate changes and mispractices in the agriculture field. Soil microbiome is a diverse system consisting of vario...

The residual characteristics and risk assessment with respect to cyazofamid and its metabolite 4-chloro-5-p-tolylimidazole-2-carbonitrile were monitored in case of Korean cabbage at different preharvest intervals during a greenhouse trial. The 0.02 kg a.i/ha of cyazofamid was sprayed twice on seven-day intervals (i.e., on day 0, 7, 14, and 21 before harvest). The liquid chromatography–tandem mass spectrometry analysis was used to monitor the residual amount of fungicide. The matrix-matched calibration curves with respect to the cyazofamid in Korean cabbage exhibited good linearity (R2 ≥ 0.999) and acceptable recoveries of 84.1%–114.9%. The biological half-life of cyazofamid in Korean cabbage was 3.18 days. During the treatment, the preharvest residue of cyazofamid in Korean cabbage 14 days before harvest (0.80 mg/kg) was lower than that specified by the MFDS–MRL (Ministry of Food and Drug Safety-Maximum Residue Limit, 2.0 mg/kg) and should be recommended as the safe preharvest-interval application limit. The hazard quotient showed low toxicity (70.58%) during the risk assessment study of cyazofamid.

Microplastics (MP) are a persistent and silent threat to the environment and are already considered a significant problem in aquatic environments. However, the presence of MP in soils and terrestrial ecosystems has been largely unexplored. Recent research has identified the risk of MP transfer from terrestrial agriculture to the human food chain. Thus, MP should be treated as a future threat to food safety and sustainable agriculture. Several reviews have focused on MP effects within global environmental matrices. However, scant investigations on the disposition, ecological impact and remediation strategies of MP have been reported in case of unexplored soil ecosystems as compared to aquatic ecosystems. Therefore, this review focuses on the contemporary global MP research with respect to research opportunities and related challenges of MP for the soil and terrestrial ecosystem from a Bangladesh perspective.

In modern agriculture, chemical pesticides are widely used to protect crop plants from insects and microbial pests, but the improper application of synthetic chemicals is hazardous for non-targeted organisms and the environment of the applied sites. The disposition mechanism of applied pesticides is highly variable in global farmlands; therefore, the sustainable remediation of pesticide-contaminated sites is a priority research area for the ecofriendly management of these pollutants. Furthermore, researchers discourage the physical and chemical remediation of pesticides and their metabolites because of issues related to time consumption, cost effectiveness, and sustainability compared to microbial and enzymatic remediation. Microorganisms from diverse taxonomic groups, such as bacteria, fungi, and algae, are known to effectively metabolize pesticides and/or alter the chemical structures facilitating their degradation and making the contaminated environment free from harmful pesticide residues. Similarly, catalytic enzymes, such as laccase and peroxidase, can also efficiently remediate most organic and chemical pesticides. The elite strains of microorganisms, singly or as a mixed consortium, can be used for compelling biological pesticide remediation. However, several research uncertainties, including inconsistent performance, adaptation under varying weather conditions, and application difficulties, may limit the wider practical application of these potential ecofriendly bioremediation approaches. This study reviews recent literature on the prospect and challenges of ecofriendly bioremediation approaches for the reclamation of pesticide-contaminated sites. This study also discusses the underlying mechanism of the microbe- and enzyme-mediated bioremediation of pesticides with a sustainable research prospective.

Phosphorus (P) fixation limits availability of P to plants in tropical soil, which is a major constraint for crop production. The aim of our research was to isolate, screen and characterize phosphate solubilizing bacteria (PSB) from wheat and evaluate their efficacy in P nutrition in wheat. Upon screening, 9 isolates showing varying level of phosphate solubilizing activity in both agar plate and broth assays using Pikovskaya’s medium were obtained. The pH of the culture media was decreased with increased bacterial growth suggesting that they might secrete organic acids to solubilize insoluble phosphorus. In vitro wheat seedling bioassay with two superior PSB isolates (PSB1 and PSB8) and varying sources of P revealed that both isolates significantly enhanced seedling growth (shoot and root length, shoot and root dry weight) and nutrient contents (%N, %P and %K) in plant tissue compared to control (no PSB). The performance of PSB8 was superior to PSB1 in respect of all the parameters studied. The PSB8 was tentatively identified as Pseudomonas sp. through 16S rRNA gene sequencing. Our results suggest that Pseudomonas sp. PSB8 isolated from wheat might be useful for improving P nutrition in wheat in soils with low available P.