Changes in Metabolite Profiling and Expression Levels of Key Genes Involved in the Terpenoid Biosynthesis Pathway in Garden Sage (Salvia officinalis) under the Effect of Hydrazine Hydrate.

Mutagenesis is a highly efficient tool for establishing genetic variation and is widely used for genetic enhancement in various plants. The key benefit of mutation breeding is the prospect of enhancing one or several characteristics of a variety without altering the genetic background. In this study, we exposed the seeds of Salvia officinalis to four concentrations of hydrazine hydrate (HZ), i.e., (0%, 0.1%, 0.2%, and 0.3%) for 6 h. The contents of terpenoid compounds in the S. officinalis plantlets driven from the HZ-treated seeds were determined by GC-MS, which resulted in the identification of a total of 340 phytochemical compounds; 163 (87.48%), 145 (84.49%), 65 (97.45%), and 62 (98.32%), from the four concentrations of HZ (0%, 0.1%, 0.2%, and 0.3%), respectively. Furthermore, we used the qRT-PCR system to disclose the "transcriptional control" for twelve TPS genes related to terpenoid and terpene biosynthesis, namely, SoGPS, SoMYRS, SoNEOD, SoCINS, SoSABS, SoLINS, SoFPPS, SoHUMS, SoTPS6, SoSQUS, SoGGPS, and SoGA2. Altogether, results are likely to ensure some positive relationship between the concentrations of the chemical mutagen HZ used for treating the seeds, the type and amount of the produced terpenes, and the expression of their corresponding genes.

Effect of silver nanoparticles on tropane alkaloid production of transgenic hairy root cultures of Hyoscyamus muticus L. and their antimicrobial activity.

The utilization of nanotechnology and biotechnology for enhancing the synthesis of plant bioactive chemicals is becoming increasingly common. The hairy root culture technique can be used to increase secondary metabolites such as tropane alkaloids. Agrobacterium was used to induce hairy roots from various explants of Hyoscyamus muticus. The effect of nano-silver particles (AgNPs) at concentrations of 0, 25, 50, 100, and 200 mg/L on tropane alkaloids synthesis, particularly hyoscyamine and scopolamine, was studied in transgenic hairy root cultures. Different types of explants obtained from 10-day-old seedlings of H. muticus were inoculated with two strains of Agrobacterium rhizogenes (15,834 and A4). The antimicrobial activity of an ethanolic extract of AgNPs-induced hairy root cultures of H. muticus was tested. The frequency of hairy roots was higher in hypocotyl, root, leaf, and stem explants treated with A. rhizogenes strain A4 compared to those treated with strain 15,834. In transgenic hairy root cultures, AgNPs application at a concentration of 100 mg/L resulted in the highest total tropane alkaloid production, which exhibited broad-spectrum antimicrobial activity. The study demonstrated the potential of nano-silver as an elicitor for promoting the production of target alkaloids in Hyoscyamus muticus hairy root cultures, which exhibit high biological activity.

Constitutive overexpression of GsIMaT2 gene from wild soybean enhances rhizobia interaction and increase nodulation in soybean (Glycine max).

BACKGROUND: Since the root nodules formation is regulated by specific and complex interactions of legume and rhizobial genes, there are still too many questions to be answered about the role of the genes involved in the regulation of the nodulation signaling pathway. RESULTS: The genetic and biological roles of the isoflavone-7-O-beta-glucoside 6″-O-malonyltransferase gene GsIMaT2 from wild soybean (Glycine soja) in the regulation of nodule and root growth in soybean (Glycine max) were examined in this work. The effect of overexpressing GsIMaT2 from G. soja on the soybean nodulation signaling system and strigolactone production was investigated. We discovered that the GsIMaT2 increased nodule numbers, fresh nodule weight, root weight, and root length by boosting strigolactone formation. Furthermore, we examined the isoflavone concentration of transgenic G. max hairy roots 10 and 20 days after rhizobial inoculation. Malonyldaidzin, malonylgenistin, daidzein, and glycitein levels were considerably higher in GsMaT2-OE hairy roots after 10- and 20-days of Bradyrhizobium japonicum infection compared to the control. These findings suggest that isoflavones and their biosynthetic genes play unique functions in the nodulation signaling system in G. max. CONCLUSIONS: Finally, our results indicate the potential effects of the GsIMaT2 gene on soybean root growth and nodulation. This study provides novel insights for understanding the epistatic relationship between isoflavones, root development, and nodulation in soybean. HIGHLIGHTS: * Cloning and Characterization of 7-O-beta-glucoside 6″-O-malonyltransferase (GsIMaT2) gene from wild soybean (G. soja). * The role of GsIMaT2 gene in the regulation of root nodule development. *Overexpression of GsMaT2 gene increases the accumulation of isoflavonoid in transgenic soybean hairy roots. * This gene could be used for metabolic engineering of useful isoflavonoid production.

Radio-Protective Effects of Stigmasterol on Wheat (Triticum aestivum L.) Plants.

Ionizing radiation is abiotic stress limiting the growth and productivity of crop plants. Stigmasterol has positive effects on the plant growth of many crops. The role of stigmasterol in alleviating the effects of ionizing radiation on plant metabolism and development is still unclear. Therefore, the study aimed to investigate the effects of pretreatments with γ-radiation (0, 25, and 50 Gy), foliar application of stigmasterol (0, 100, and 200 ppm), and their interaction on the growth, and biochemical constituents of wheat (Triticum aestivum L., var. Sids 12) plants. Gamma radiation at 25 Gy showed no significant difference in plant height, root length, no. of leaves, shoot fresh weight, root fresh weight, Chl a, ABA, soluble phenols, and MDA compared to the control values. Gamma rays at 50 Gy inhibited shoot and root lengths, flag leaf area, shoot fresh and dry weights, photosynthetic pigments, total soluble sugars, proline, and peroxidase activity. However, it stimulated total phenols, catalase activity, and lipid peroxidation. On the other hand, stigmasterol at 100 ppm showed no significant effects on some of the physiological attributes compared to control plants. Stigmasterol at 200 ppm improved plant growth parameters, photosynthetic pigments, proline, phenols, antioxidant enzyme, gibberellic acid, and indole acetic acid. Correspondingly, it inhibited total soluble sugars, abscisic acid, and lipid peroxidation. Moreover, the application of stigmasterol caused the appearance of new polypeptides and the reappearance of those missed by gamma radiation. Overall, stigmasterol could alleviate the adverse effects of gamma radiation on wheat plants.