Emerging pollutant in surface water bodies: a review on monitoring, analysis, mitigation measures and removal technologies of micro-plastics.

Water bodies play a crucial role in supporting life, maintaining the environment, and preserving the ecology for the people of India. However, in recent decades, human activities have led to various alterations in aquatic environments, resulting in environmental degradation through pollution. The safety of utilizing surface water sources for drinking and other purposes has come under intense scrutiny due to rapid population growth and industrial expansion. Surface water pollution due to micro-plastics (MPs) (plastics < 5 mm in size) is one of the emerging pollutants in metropolitan cities of developing countries because of its utmost resilience and synthetic nature. Recent studies on the surface water bodies (river, pond, Lake etc.) portrait the correlation between the MPs level with different parameters of pollution such as specific conductivity, total phosphate, and biological oxygen demand. Fibers represent the predominant form of MPs discovered in surface water bodies, exhibiting fluctuations across seasons. Consequently, present study prioritizes understanding the adaptation, prevalence, attributes, fluctuations, and spatial dispersion of MPs in both sediment and surface water environments. Furthermore, the study aims to identify existing gaps in the current understanding and underscore opportunities for future investigation. From the present study, it has been reported that, the concentration of MPs in the range of 0.2-45.2 items/L at the Xisha Islands in the south China sea, whereas in India it was found in the range of 96 items/L in water samples and 259 items/kg in sediment samples. This would certainly assist the urban planners in achieving sustainable development goals to mitigate the increasing amount of emergent pollutant load.

Comparative combustion, emission, and performance analysis of a diesel engine using carbon nanotube (CNT) blended with three different generations of biodiesel.

Nano-additives are being employed in successive generations of biodiesels to increase the performance characteristics and output of diesel engines. In this study, the impact of mixing carbon nanotubes (CNT) with three different generations of biodiesel in a diesel engine is assessed. With 100 ppm of CNT nanoparticles mixed together, pure biodiesels made from first-generation oil (soybean), second-generation oil (neem), and third-generation oil (Nannochloropsis oculata microalgae) are used for the analysis. With an engine load ranging from 0 to 100%, a one-cylinder, four-stroke, direct injection diesel engine is employed. The engine has a water-cooling system, a compression ratio of 17.5:1, and a fuel injection angle of 23° before TDC. The evaluated engines' improved performance and lower emissions serve as proof of the outcomes. The results are evidenced by the lower emissions and higher performance of the tested engines. The biodiesel containing CNT nanoparticles enhanced the cylinder pressure by 0.8-10.69%, the heat release rate (HRR) by 6.38-21.69%, and the brake thermal efficiency (BTE) by 0.32-1.62%. Subsequently, it reduced the brake-specific fuel consumption (BSFC) by 2.53-8.13%, the brake-specific energy consumption (BSEC) by 1.07-3.77%, the smoke opacity (BSN) by 6.26-12.85%, the particulate matter (PM) emissions by 11.04-18.33%, and the carbon dioxide (CO2) emissions by 2.53-8.14% at full engine load. However, an increase in 13.62-18.37% nitrogen emissions (NOx) emissions is also observed with the addition of CNT at 100% load. The investigation supports the use of CNT nano-additives in diesel engines for improved performance and reduced emissions.

Expression of an insecticidal fern protein in cotton protects against whitefly.

Whitefly (Bemisia tabaci) damages field crops by sucking sap and transmitting viral diseases. None of the insecticidal proteins used in genetically modified (GM) crop plants to date are effective against whitefly. We report the identification of a protein (Tma12) from an edible fern, Tectaria macrodonta (Fee) C. Chr., that is insecticidal to whitefly (median lethal concentration = 1.49 µg/ml in in vitro feeding assays) and interferes with its life cycle at sublethal doses. Transgenic cotton lines that express Tma12 at ∼0.01% of total soluble leaf protein were resistant to whitefly infestation in contained field trials, with no detectable yield penalty. The transgenic cotton lines were also protected from whitefly-borne cotton leaf curl viral disease. Rats fed Tma12 showed no detectable histological or biochemical changes, and this, together with the predicted absence of allergenic domains in Tma12, indicates that Tma12 might be well suited for deployment in GM crops to control whitefly and the viruses it carries.

Induction and establishment of somatic embryogenesis in elite Indian cotton cultivar (Gossypium hirsutum L. cv Khandwa-2).

Embryogenesis in cotton is a difficult task due its genome dependency. We used 3 cotton cultivars (Khandwa-2, G. Cot. 10, and BC-68­2) and Coker-312 as control for regeneration. Efficient somatic embryogenesis was induced in agronomically important Indian cotton cultivars, Khandwa-2 and G. Cot. 10. For callusing in all the cultivars, different media combinations were tried. Embryogenesis was initiated on a hormone-free MS medium (MSB). For embryo maturation and recovery excess of L-glutamine and l-asparagine were used. Khandwa-2 somatic embryos were successfully regenerated into plants. However, no plantlet was obtained in case of G. Cot. 10. Callus induction was also observed in BC-68­2 but there was no embryogenesis observed. The study indicated that the medium and genotype significantly effects embryogenesis. An efficient protocol is described here for regenerating plants via somatic embryogenesis in an elite Indian cotton cultivar Khandwa-2.

Development of insect resistant transgenic cotton lines expressing cry1EC gene from an insect bite and wound inducible promoter.

Transgenic cotton lines were developed for high-level expression of a synthetic cry1EC gene from a wound inducible promoter. The tobacco pathogenesis related promoter PR-1a was modified by placing CaMV35S promoter on its upstream in reverse orientation. The resultant chimeric promoter CaMV35S(r)PR-1a expressed constitutively and was further up-regulated at the site of feeding by insects. It was induced more rapidly by treatment with salicylic acid (SA). The CaMV35S(r)PR-1a cry1EC expressing transgenic lines of cotton showed 100% mortality of Spodoptera litura larvae. The tightly regulated low-level expression of PR-1a was modified to a highly expressing constitutive expression by CaMV35S placed in reverse orientation. Salicylic acid treatment and wounding enhanced the expression further by the chimeric promoter. The leaves expressed more delta-endotoxin around the sites of insect bites. The levels of expression and induction varied among different transgenic lines, suggesting position effect. Some of the transgenic lines that expressed Cry1EC from the chimeric promoter at a low level also showed 100% mortality when induced with salicylic acid. A highly expressing insect bite and wound inducible promoter is desirable for developing insect resistant transgenic plants.