Plants express various antimicrobial peptides including thionins to protect themselves against pathogens. It was recently found that, in addition to four thionin genes, Arabidopsis contains 67 thionin-like (ThiL) genes including six pseudogenes. It is known that thionins have antimicrobial activity and are part of the plant defense system, however, nothing is known about ThiL genes. In this study, we present a bioinformatic analysis of the (ThiL) gene family in Arabidopsis. We identified 15 different motifs which positioned the ThiL peptides in four groups. A comparison of amino acid sequences showed that the ThiL peptides are actually more similar to the acidic domain of thionin proproteins than to the thionin domain. We selected 10 ThiL genes to study the expression and possible function in the Arabidopsis plant. RT-PCR and promoter:GUS fusions showed that most genes were expressed at a very low level but in several organs and at different developmental stages. Some genes were also expressed in syncytia induced by the beet cyst nematode Heterodera schachti in roots while others were downregulated in syncytia. Some overexpression lines supported lower number of nematodes that developed on the roots after inoculation. Two of the genes resulted in a strong hypersensitive response when infiltrated into leaves of Nicotiana benthamiana. These results indicate that ThiL genes might be involved in the response to biotic stress. ThiL genes have been expanded in the Brassicales and specifically the Brassicaceae. The most extreme example is the CRP2460 subfamily that contains 28 very closely related genes from Arabidopsis which are mostly the result of tandem duplications.

Water pollution damages the aquatic environment due to the presence of organic contaminants, which in turn is distressing to the ecosystem. Photocatalytic activity is a greener and promising method to degrade these organic contaminants. In this research, we present the degradation of diverse water pollutants through zinc/iron oxide nanoparticles serving as photocatalysts. The photocatalyst was studied for its efficiency to photodegrade congo red, brilliant green and para nitro phenol. Moreover, it also presented an antibacterial activity against the bacterium E. coli. Photocatalyst was characterized via X-ray diffraction, scanning electron microscopy-energy dispersive X-ray spectroscopy, and fourier-transform infrared spectroscopy. Tauc plot was used to measure the optical band gap (1.84 eV). The effect of various parameters such as catalyst dose, contact time, dye dose/concentration and pH were also investigated to determine the optimum point of maximum degradation through response surface methodology. A face-centered composite design was used, and a quadratic model was followed by congo red, brilliant green dyes and para nitrophenol. The maximum photodegradation efficiencies were 99%, 94.3%, and 78.5% for congo red, brilliant green and phenol, respectively. Quantum yield for congo red, brilliant green and para-nitrophenol were 9.62 × 10⁻⁸, 1.17 × 10⁻⁷ and 4.11 × 10⁻⁷ molecules/photons, while the reaction rates were 27.1 µmolg⁻¹h⁻¹, 29.61 µmolg⁻¹h⁻¹ and 231 µmolg⁻¹h⁻¹, respectively.

Zinc as a micronutrient is highly essential for animals and plants to attain optimum growth and development. Zinc-deficient soils result in stunted and abnormal growth of plants. Three wheat varieties, i.e., Zincol-2016 (biofortified), Galaxy-2013, and Punjab-2011 (both non-biofortified), were sown in pots containing fertile soil in a completely randomized design with four replicas. The seedlings were sprayed with four zinc solutions (Control, 0.03%, 0.06%, and 0.09% of Zn as ZnSO₄.7H₂O) 40 days after sowing. It was observed that the impact of 0.06% zinc spray was more pronounced on wheat plants as compared to that of 0.03% and 0.09%. More pronounced improvement in growth, chlorophyll content, total soluble proteins, and sugars was observed in cv. Zincol-2016 as compared to that in the other two varieties, Galaxy-2013 and Punjab-2011. Similarly, Zn foliar spray significantly enhanced root, straw, and grain K⁺, Cu²⁺, Zn²⁺, and Fe²⁺ contents in all three cultivars. In contrast, grain phytate contents were reduced with increased supplementation of Zn. Data revealed that grain yield was improved significantly by exogenous application of zinc, especially at 0.06% in all three wheat varieties, but being more promising in Zincol-2016. Furthermore, Zincol-2016 accumulated higher zinc contents in grains as compared to that in Galaxy-2013 and Punjab-2011. Foliar application of zinc resulted in higher uptake and accumulation of this element from soil to seeds, thereby resulting in improved vegetative growth.

Chlorophyll a fluorescence (CF) is an effective tool to measure the photosynthetic efficiency, functional capacity and structural stability of photosystem-II and the overall health status of plants in normal or stress environment. The present study was designed to investigate the response of PSII through CF in pearl millet (Pennisetum glaucum L.) grown under saline stress (200 mM NaCl). In first round, eighteen varieties were screened for salinity tolerance at vegetative stage. The relative rate of reduction in biomass, pigments, Na⁺ and K⁺ indicated YBS-93, YBS-94 and YDR-8-1 varieties as tolerant and the YBS-98, YCMP-19 and YCMP-34 varieties as salt sensitive varieties. While the chlorophyll-a fluorescence transient analysis, raw OJIP induction curves, Fo and Fm normalised curves exhibited that substantial variation in CF occurred at the O, J, I and P steps in salt sensitive varieties. The comprehensive investigation of JIP test attributes proposed that salinity stress triggered photoinhibition of PSII via disturbance in absorption of light from reaction centres (ABS), low electron transport and photochemical fluxes (ETo, ψ0 & ɸEo) and increased dissipation fluxes (DIo & ɸDo). However, increased dissipation energy (DIO/RC) under salinity stress acts as a preventative control to protect PSII from photooxidative damage in the thylakoid membrane. While photoinhibition of PSII resulted in decrease in quantum yield of PSII (Fv/Fm) and performance index (Pi) under salinity stress. These findings provided important understanding of the salinity tolerance in pearl millet and have opened avenues to further explore the molecular signalling pathways involved in salinity tolerance.