Synthetic fertilizers are widely employed in agriculture relative to biofertilizers. Long-term use affects soil fertility, plant vigor, human and livestock health, and the soil microbial community. Seaweeds were employed as biofertilizers in sustainable agriculture to overcome this issue and boost the agricultural productivity. Therefore, the current study investigates the effect of wheat seeds priming with the aqueous extracts of Ulva linza or Corallina officinalis seaweeds at various concentrations (5, 10, 15, 20, and 30%). Wheat grains were primed with seaweed extracts and grown in petri dishes, and the germination rate, growth attributes, physiological parameters, cytological traits, and molecular analyses were evaluated. The physico-chemical characterization revealed that U. linza possessed higher levels of ash, soluble proteins, and sugars, as well as essential macronutrients and amino acids, than C. officinalis. Seedling growth parameters, physiological characteristics, and mitotic index all showed a substantial increase in low concentrations of both extracts when compared to the control. Higher concentrations, on the other hand, exhibited an inhibitory effect as well as certain chromosomal abnormalities. In the treated seedlings, new proteins were expressed, which could be owing to the activity of bioactive components in the extracts. As compared to untreated seedlings, PCR-RAPD analysis utilizing five markers revealed that both seaweed extracts triggered low and high molecular weight DNA fragments, as well as fragments specific to each extract. Seaweed extracts could be employed as an environmentally friendly and soil-safe alternative to typical chemical fertilizers.

There is a need to enhance the production of bioactive secondary metabolites and to establish new production systems, e.g., for liver-protective compounds of Silybum marianum seeds. Quantifying and identifying the produced phytochemicals, and examining their protective effects against genotoxic agents, is of great interest. This study established a protocol for the qualitative and quantitative production of hepatoprotective compounds in cotyledon-derived Silybum marianum callus through optimized supplementation of the MS medium with the growth regulators 2,4-D, benzylaminopurine, myoinositol, and asparagine. High-performance liquid chromatography (HPLC) coupled with electrospray ionisation mass spectrometry (ESI-MS) allowed for identification and quantification of the produced compounds. None of the growth medium combinations supported a detectable production of silymarin. Instead, the generated calli accumulated phenolic acids, in particular chlorogenic acid and dicaffeoylquinic acid, as revealed by HPLC and mass spectrometric analysis. 4-Nitro-o-phenylenediamine (NPD) was employed in the AMES-test with Salmonella typhimurium strain TA98 because it is a potent mutagen for this strain. Results revealed that callus extract had a high anti-genotoxic activity with respect to standard silymarin but more evident with respect seed extract. The callus produced chlorogenic acid and dicaffeoylquinic acid, which revealed higher bioactivity than silymarin. Both compounds were not formed or could not be detected in the seeds of Silybum marianum Egyptian ecotype.

Drought has been recognized as a potential challenge to maize production around the world, particularly in arid and semi-arid regions. The primary focus of the present study was to investigate the metabolic and physiological adjustment mechanisms as well as drought-responsive gene expression patterns in five maize (Zea mays L.) genotypes (G314, G2, G10, G123, and G326) with varying drought-tolerance capacities at the vegetative stage. Twenty-one days-old maize plants from five maize genotypes were submitted to a well-watered (10 days) watering interval as a control, mild water stress (15 day interval), and severe water stress (20 day interval) treatments in a field experiment for two successive seasons (2019 and 2020). For all maize genotypes, the results showed that water stress significantly reduced plant height, leaf area, biomass, and yield characteristics. However, water stress, which was associated with the length of the watering interval, increased the concentrations of glycine betaine, amino acids, proline, phenols, flavonoids, soluble proteins, and soluble sugars, as well as catalase and peroxidase activities. On the transcriptional level, prolonged water stress increased the expression of drought-responsive genes (LOS5, Rad17, NCED1, CAT1, and ZmP5CS1), with G10 and G123 genotypes being the most drought-resistant. Herein, genotypes G10 and G123 were shown in this study to be relatively water stress tolerant due to improved osmoregulatory, antioxidant, and metabolic activities under water stress conditions, as well as the fact that they were endowed with stress-responsive genes.

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