title: Microbe-based technology ameliorates glandular trichomes, secondary metabolites and antioxidants in Pelargonium graveolens L'Hér.
abstract: BACKGROUND
  Despite the vast exploration of microbes for plant health, there is a lack of knowledge about the synergistic effects of specific microorganisms in sustainable agriculture, especially in medicinal plants such as Pelargonium graveolens L'Hér. The aim of this study was to evaluate how synergistic microbes Trichoderma harzianum ThU, Glomus intraradices and Bacillus subtilis CIM affected crop productivity, secondary metabolites and glandular trichome number in P. graveolens.
  
  
  RESULTS
  The results demonstrated a significant (P < 0.05) increase in plant growth, secondary metabolites, total chlorophyll, carotenoids, carbohydrates, total phenolics, total flavonoids, free radical-scavenging activity and total antioxidant capacity of P. graveolens treated with synergistic bioinoculants as compared with the control. Most interestingly, an increase in essential oil by 32% in the treatment with all three microbes was observed. Furthermore, the principal aroma compounds citronellol and geraniol also increased in the same treatment. A positive and direct correlation was observed between essential oil content and number of glandular trichomes in all treatments.
  
  
  CONCLUSIONS
  The present study highlights an explicit amalgamation of prospective microbes showing potential for synergism that act as biostimulants in enhancing plant production and improving the antioxidant and aroma profile of P. graveolens. © 2016 Society of Chemical Industry.
authors.affiliation: Department of Microbial Technology and Nematology, CSIR - Central Institute of Medicinal and Aromatic Plants, PO CIMAP, Lucknow, 226015, India.
authors.forename: Rupali
authors.initials: R
authors.lastname: Gupta
authors.affiliation: Department of Microbial Technology and Nematology, CSIR - Central Institute of Medicinal and Aromatic Plants, PO CIMAP, Lucknow, 226015, India.
authors.forename: Akanksha
authors.initials: A
authors.lastname: Singh
authors.affiliation: Department of Microbial Technology and Nematology, CSIR - Central Institute of Medicinal and Aromatic Plants, PO CIMAP, Lucknow, 226015, India.
authors.forename: Rakesh
authors.initials: R
authors.lastname: Pandey
mesh_terms: D000383:Agriculture / Q000379:methods; D000975:Antioxidants / Q000032:analysis* / Q000378:metabolism; D001412:Bacillus subtilis / Q000502:physiology*; D018533:Biomass; D016166:Free Radical Scavengers / Q000032:analysis; D055137:Glomeromycota / Q000502:physiology*; D056265:Microbial Interactions; D009822:Oils, Volatile / Q000032:analysis; D031316:Pelargonium / Q000737:chemistry / Q000378:metabolism / Q000382:microbiology*; D010936:Plant Extracts / Q000032:analysis; D010946:Plants, Medicinal / Q000737:chemistry / Q000378:metabolism / Q000382:microbiology; D064210:Secondary Metabolism; D014242:Trichoderma / Q000502:physiology*; D064201:Trichomes / Q000737:chemistry / Q000378:metabolism / Q000382:microbiology*
chemical_list: D000975:Antioxidants; D016166:Free Radical Scavengers; D009822:Oils, Volatile; D010936:Plant Extracts
keywords: Pelargonium graveolens; microbes; secondary metabolites; trichome