Impact of biochar on the yield and nutritional quality of tomatoes (Solanum lycopersicum) under drought stress.

BACKGROUND: Undeviating climatic instabilities have increased the incidents of drought. Crop performance and yield attributes of tomatoes are negatively affected by drought stress. Biochar is an organic amendment that can increase crop yield and nutritional value under water-deficient conditions by retaining water and providing nutrients (nitrogen, phosphorus, potassium, and other trace elements). RESULTS: The present study was designed to investigate the effects of biochar on tomato plant physiology, yield, and nutritional quality under deficit moisture regimes. Plants were subjected to two biochar levels (0.1% and 0.2%) and four moisture levels [100%, 70%, 60%, and 50% field capacities (FCs)]. Drought stress, especially 50D (50% FC), severely affected the plant morphology, physiology, yield, and fruit quality attributes. However, plants grown in biochar-amended soil showed significant increase in the studied attributes. Plant height, root length, fresh and dry weight of root, the number of fruits per plant, fruit fresh and dry weight, ash percent, crude fat, crude fiber, crude protein, and lycopene contents were increased in plants grown in biochar-amended soil under control and drought stress. CONCLUSION: Biochar at 0.2% application rate depicted a more pronounced increment in the studied parameters than 0.1% and can save 30% water without compromising tomato crop yield and nutritional value. © 2023 Society of Chemical Industry.

Phyto-Synthesis, Characterization, and In Vitro Antibacterial Activity of Silver Nanoparticles Using Various Plant Extracts.

Aloe vera, Mentha arvensis (mint), Coriandrum sativum (coriander), and Cymbopogon citratus (lemongrass) leaf extracts were used to synthesize stable silver nanoparticles (Ag-NPs) by green chemistry. UV-vis spectrophotometry, X-ray diffraction (XRD), thermogravimetric analysis (TGA), scanning electron microscopy (SEM), and energy dispersive X-ray (EDX) spectroscopy techniques were used to characterize these biosynthesized nanoparticles. The data indicated that the silver nanoparticles were successfully synthesized, and the narrower particle size distribution was at 10-22 nm by maintaining a specific pH. As a short-term post-sowing treatment, Ag-NP solutions of different sizes (10 and 50 ppm) were introduced to mung bean seedlings, and the overall increase in plant growth was found to be more pronounced at 50 ppm concentration. The antibacterial activity of Ag-NPs was also investigated by disc diffusion test, minimum inhibitory concentration (MIC), and minimum bactericidal concentration (MBC) test. The zones of inhibition (ZOI) were shown by Escherichia coli (E. coli) (1.9, 2.1, 1.7, and 2 mm), followed by Staphylococcus aureus (S. aureus) (1.8, 1.7, 1.6, and 1.9 mm), against coriander, mint, Aloe vera, and lemongrass, respectively. MIC and MBC values of E. coli, and S. aureus ranged from 7 to 8 µg/mL. Overall, this study demonstrates that Ag-NPs exhibit a strong antimicrobial activity and thus might be developed as a new type of antimicrobial agent for the treatment of bacterial infection.

Floral Characterization of Pomegranate Genotypes to Improve Hybridization Efficiency.

Pomegranate (Punica granatum) has staminate (male), androgynous (hermaphrodite), and intermediate flower types. Floral characterization is difficult for breeding efficiency across many pomegranate genotypes in Pakistan, which is essential for pomegranate cultivar enhancements. The present research focused on the floral characterization and breeding efficiency of fifteen pomegranate genotypes. Flower sex ratio, floral morphological parameters, i.e., flower length, ovary width, flower notch, flower tip and stigma with style length, and fruit set percentage were examined during the experiment. In terms of sex ratio, male flowers were found to be higher among all genotypes. Due to clear differences in flower length, width, and heterostyly facilitating visual identification of the hermaphrodite flowers, genotype Ternab-2, Kandhari White, and Kandhari Red had higher fruit set (≥70%) among all cross combinations attempted. Genotype Sava had higher flower length and heterostyly of hermaphrodite flower type, but ovary width was not very distinct, leading to average crossing success (85-34%). In conclusion, single or combination of morphological characters can be used for accurate identification of hermaphrodite flowers, which can improve hybrid efficiency and fruit set after artificial cross-pollination.

Interface-Induced Near-Infrared Response of Gold-Silica Hybrid Nanoparticles Antennas.

We proposed an IR absorber hybrid nanoantenna comprise of two overlapping gold nanoparticles residing over larger a silica nanoparticle. A wet chemical route was employed to prepare the hybrid structure of nanoantenna. High-resolution transmission electron microscope was used to measure the size and morphology of the nanoantenna. The Hybrid nanoantenna was excited by electron beam to investigate the optical response over a large wavelength range using Electron Energy Loss Spectroscopy. The beam of the electron was focused and we measured the electron energy loss spectra at different point of interest, which confirmed the of Low Energy Surface Plasmon Politron resonances in the IR region. The optical response of the nanoantenna was simulated numerically by employing Electric Hertzian dipole using finite element method with frequency domain solver in CST Microwave Studio. We used the Electric Hertzian dipole approach for the first time to model the Electron Energy Loss Spectroscopy experiment. The Electron Energy Loss Spectroscopy experimental results with their numerically simulated values confirmed the plasmonic resonance at the interface of the two overlapped gold nanoparticles.