title: Induced drought tolerance through wild and mutant bacterial strain Pseudomonas simiae in mung bean (Vigna radiata L.).
abstract: The present study focused on the overproducing mutant of a plant growth promoting rhizobacterium (PGPR) Pseudomonas simiae strain AU (MTCC-12057) for significant drought tolerance in mung bean plants. Five mutants namely AU-M1, AU-M2, AU-M3, AU-M4 and AU-M5 were made after treatment of wild type strain with N-methyl-N-nitro-N-nitrosoguanidine. Mutant strain AU-M4 was recorded for enhanced ACC deaminase (ACC-D) activity, indole acetic acid (IAA) production and inorganic phosphate (Pi) solubilization compared to wild strain and other four mutant strains under drought condition. AU-M4 showed higher phosphate solubilization index (8.17) together with higher ACC-D activity (98 nmol/mg/h) and IAA concentration (69.35 µg/ml) compared with the wild type P. simiae strain AU ACC-D activity (79 nmol/mg/h) and IAA concentration (38.98 µg/ml) respectively. In this report, we investigated the effect of both wild and mutant type bacterial strain on mung bean plants under drought stress. Results showed that mutant AU-M4 and wild type strain AU inoculated plants exhibited superior tolerance against drought stress, as shown by their enhanced plant biomass (fresh weight), higher water content, higher proline accumulation and lower osmotic stress injury. Mutant AU-M4 and wild strain AU inoculated plants reduced the ethylene level by 59 and 45% respectively, compared to the control under stress condition. Furthermore, bacterial inoculated plants showed enhanced induced systemic drought tolerance by reducing stomata size and net photosynthesis resulting higher water content in mung bean plants that may help in survival of plants during drought condition. To mitigate the effects of drought stress, use of PGPR will be needed to ensure sufficient production of food from crop plants. Taking current leads available, concerted future research is needed in this area, particularly on field evaluation with application of potential microorganisms.
authors.affiliation: Department of Biological Science, College of Arts, Science and Humanities (CASH), Mody University of Science & Technology, Lakshmangarh, Sikar, Rajasthan, 332311, India.|Amity Institute of Microbial Technology (AIMT), Block 'E-3', 4th Floor, Amity University Campus, Sector-125, Gautam Buddha Nagar, Noida, UP, 201303, India.
authors.forename: Sarita
authors.initials: S
authors.lastname: Kumari
authors.affiliation: Department of Biological Science, College of Arts, Science and Humanities (CASH), Mody University of Science & Technology, Lakshmangarh, Sikar, Rajasthan, 332311, India.|Amity Institute of Microbial Technology (AIMT), Block 'E-3', 4th Floor, Amity University Campus, Sector-125, Gautam Buddha Nagar, Noida, UP, 201303, India.
authors.forename: Anukool
authors.initials: A
authors.lastname: Vaishnav
authors.affiliation: Department of Biological Science, College of Arts, Science and Humanities (CASH), Mody University of Science & Technology, Lakshmangarh, Sikar, Rajasthan, 332311, India.|Amity Institute of Microbial Technology (AIMT), Block 'E-3', 4th Floor, Amity University Campus, Sector-125, Gautam Buddha Nagar, Noida, UP, 201303, India.
authors.forename: Shekhar
authors.initials: S
authors.lastname: Jain
authors.affiliation: Amity Institute of Microbial Technology (AIMT), Block 'E-3', 4th Floor, Amity University Campus, Sector-125, Gautam Buddha Nagar, Noida, UP, 201303, India.
authors.forename: Ajit
authors.initials: A
authors.lastname: Varma
authors.affiliation: Department of Biological Science, College of Arts, Science and Humanities (CASH), Mody University of Science & Technology, Lakshmangarh, Sikar, Rajasthan, 332311, India. devmicro@rediffmail.com.|Amity Institute of Microbial Technology (AIMT), Block 'E-3', 4th Floor, Amity University Campus, Sector-125, Gautam Buddha Nagar, Noida, UP, 201303, India. devmicro@rediffmail.com.
authors.forename: Devendra Kumar
authors.initials: DK
authors.lastname: Choudhary
mesh_terms: D018533:Biomass; D050260:Carbohydrate Metabolism; D019755:Carbon-Carbon Lyases / Q000378:metabolism; D055864:Droughts; D005030:Ethylenes / Q000378:metabolism; D007887:Fabaceae / Q000254:growth & development / Q000382:microbiology* / Q000502:physiology*; D007210:Indoleacetic Acids / Q000378:metabolism; D009154:Mutation; D009997:Osmotic Pressure; D011392:Proline / Q000378:metabolism; D011549:Pseudomonas / Q000235:genetics / Q000254:growth & development / Q000378:metabolism / Q000502:physiology*; D012231:Rhizobium / Q000254:growth & development; D012988:Soil Microbiology
chemical_list: D005030:Ethylenes; D007210:Indoleacetic Acids; C030737:indoleacetic acid; C036216:ethylene; D011392:Proline; C033634:1-aminocyclopropane-1-carboxylate deaminase; D019755:Carbon-Carbon Lyases
keywords: ACC deaminase; Drought stress; Ethylene; Mutant; N-methyl-N-nitro-N-nitrosoguanidine; Pseudomonas simiae