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Key message: Thchit42 constitutive expression for fungal resistance showed synchronisation with leaf augmentation and transcriptome analysis revealed the Longifolia and Zinc finger RICESLEEPER gene is responsible for plant growth and development. Pelargonium graveolens essential oil possesses significant attributes, known for perfumery and aromatherapy. However, optimal yield and propagation are predominantly hindered by biotic stress. All biotechnological approaches have yet to prove effective in addressing fungal resistance. The current study developed transgenic geranium bridging molecular mechanism of fungal resistance and plant growth by introducing cassette 35S::Thchit42. Furthermore, 120 independently putative transformed explants were regenerated on kanamycin fortified medium. Primarily transgenic lines were demonstrated peak pathogenicity and antifungal activity against formidable Colletotrichum gloeosporioides and Fusarium oxysporum. Additionally, phenotypic analysis revealed ~ 2fold increase in leaf size and ~ 2.1fold enhanced oil content. To elucidate the molecular mechanisms for genotypic cause, de novo transcriptional profiles were analyzed to indicate that the auxin-regulated longifolia gene is accountable for augmentation in leaf size, and zinc finger (ZF) RICESLEEPER attributes growth upregulation. Collectively, data provides valuable insights into unravelling the mechanism of Thchit42-mediated crosstalk between morphological and chemical alteration in transgenic plants. This knowledge might create novel opportunities to cultivate fungal-resistant geranium throughout all seasons to fulfil demand. [ABSTRACT FROM AUTHOR]

Background: The flux of isoprenoids and the total accumulation of triterpenoid saponins known as centellosides in C. asiatica are controlled by the key genes of the Mevalonate pathway (MVA). These genes were reported to have positive regulation of the pathway in providing isoprenoid moieties. Though, some information is available on the pathway and secondary metabolites. However, most of the pathway steps are not characterized functionally. Methodology and Results: For the study, full-length pathway gene Hydroxymethyl glutaryl-CoA-synthase (CaHMGS; GenBank accession number: MZ997833), was isolated from previously annotated transcriptome data of Centella asiatica leaves. HMGS has been successfully cloned and heterologously expressed in bacteria E. coli strain DH5α. The cloned gene has been sequenced and further characterized through in silico studies by different bioinformatics tools. Also, the gene sequences have been submitted in NCBI. In silico studies of isolated gene sequence revealed the nature, characteristics of genes. The ORF of HMGS is 1449 bp encoding 482 amino acids. Predicted molecular weight (MW) of HMGS was 48.09 kDa and theoretical pI was 5.97. Blast results and Multiple sequence alignments of the gene showing the similarity with HMGS of other plants of their respective families. The Molecular Evolutionary Genetic Analysis (MEGA) version 10.1.6 was used to construct a phylogenetic tree. Differential tissue-specific expression of different plant parts was also checked. Tissue expression patterns unveiled that the highest expression level of the CaHMGS had been seen in the roots and lowest in the node of the plant. Functional complementation experiment of the CaHMGS in Saccharomyces cerevisiae wild strain YSC1021 and haploid strain YSC1021 which lack HMGS protein confirmed that the CaHMGS gene encodes functional CaHMGS that catalyzed the biosynthesis of mevalonate in yeast. Conclusions: The gene was reported, cloned and characterized first time in Centella asiatica. Understanding this biosynthetic pathway gene will further help in the improvement of plants for enhanced secondary metabolites production. [ABSTRACT FROM AUTHOR]

Gymnemic acids (a group of triterpenoid saponins) found in Gymnema sylvestre (Retz.) R.Br. ex Sm. works as the main hypoglycaemic active components. These can be the potential active pharmaceutical ingredient (API) to be used by pharmaceutical industries in modern medicines against diabetes. The present study aims to investigate the effectiveness of sodium nitroprusside (SNP) treatment for enhancement of cell suspension culture biomass and to quantify the production of deacylgymnemic acid, gymnemagenin, gymnemic acid IV and gymnemic acid XVII contents. Callus was obtained from in vitro derived leaves of G. sylvestre on MS medium fortified with 3.0 mg/L 2, 4-d (2, 4-dichlorophenoxyacetic acid) and 2.0 mg/L Kn (Kinetin), and the same were used further to produce cell suspension cultures. Cell suspensions were exposed to different concentrations of SNP (5, 10, 20 and 40 μM) and data were collected at 20, 30 and 40 days. Out of the tested concentrations, 20 μM SNP had the highest level of cell culture growth (398.94 ± 8.32 g/L Fresh cell weight (FCW) and 40.00 ± 0.75 g/L Dry cell weight (DCW) on 40-day as compared to control (MS with 3.0 mg/L 2, 4-d + 2.0 mg/L Kn). High-performance liquid chromatography analysis showed that maximum accumulation of deacylgymnemic acid (5.51 mg/g DCW), gymnemagenin (2.80 mg/g DCW) and gymnemic acid XVII (2.08 mg/g DCW) in 20 μM SNP treatment which is (13.43, 13.86 and17.33 folds) higher than the respective control at 40 days exposure. This research suggests that G. sylvestre cell suspension culture with optimal SNP elicitation treatment could be used as a good strategy for the large-scale production of these secondary metabolites at the industrial level. Key message: This research suggests that Gymnema sylvestre cell suspension culture with SNP elicitation treatment could be used as a good strategy for the large-scale production of these secondary metabolites at the industrial level. [ABSTRACT FROM AUTHOR]

Publisher's Note Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations. Correction to: Plant Cell, Tissue and Organ Culture (PCTOC) (2021) 146:161-170 https://doi.or... An incorrect concentration of Kn (Kinetin) was specified in the initial online publication. Correction to: Sodium nitroprusside enhances biomass and gymnemic acids production in cell suspension of Gymnema sylvestre (Retz.). [Extracted from the article]