Affiliation:
1. Division of Crop Protection Indian Institute of Pulse Research, IIPR Kanpur Uttar Pradesh India
2. Division of Nematology ICAR‐Indian Agricultural Research Institute Pusa New Delhi India
3. Division of Plant Pathology ICAR‐Indian Agricultural Research Institute Pusa New Delhi India
4. Division of Plant Quarantine ICAR‐ National Bureau of Plant Genetic Resources Pusa New Delhi India
Abstract
AbstractThe effects of four nematicidal rhizobacterial isolates; Bacillus subtilis, Bacillus pumilus, Bacillus megaterium, and Bacillus cereus on infection and multiplication of root‐knot nematode, Meloidogyne incognita on tomato were compared with the application of a chemical nematicide, fluopyram 34.48% SC (Velum Prime). The bio‐efficacy trial conducted in pots preinoculated with the above isolates followed by M. incognita inoculation resulted in a significant reduction in percent root galling viz. 91.95 in B. subtilis, 84.21 in B. pumilus, 83.70 in B. megaterium, and 81.8 in B. cereus, at 75 days after inoculation (DAI). The reproduction factor of the nematode was the lowest (15.83) in B. subtilis, followed by B. pumilus (21.00), compared with 48.16 in control, with enhanced photosynthetic and transpiration rates. The mechanism of induced resistance was assessed using quantitative reverse‐transcription polymerase chain reaction (qRT‐PCR) for quantification of three key defense genes (PR‐1b, JERF3, and CAT) at 0,2,4,8 and16 days DAI. The defence genes, PR‐1b, JERF3, and CAT were expressed at 2.5–7.5‐folds in rhizobacterialtreated plants, but not in nematicide treatment. The defense enzymes viz., super oxide dismutase (SOD), polyphenol oxidase (PPO), peroxidase (PO), and phenylalanine ammonia lyase (PAL) when quantified (μmol/mg protein) showed an increase from 1.5 to 17.5 for SOD, 2.1 to 7.8 in PPO, 1.8 to 10.2 in PO, and 1.8 to 8.7 in PAL during 0 to 16 DAI, in rhizobacteria‐treated plants.
Subject
Applied Microbiology and Biotechnology,General Medicine