Abstract

In present study, a total of 104 bacteria and 96 actinomycetes were isolated from rhizosphere plant root of finger millet (Eleusine coracana) from Almora district of Uttarakhand, India. Isolates were characterized using microscopic and morphological methods followed by their biochemical test. Based on functional tests, four most promising isolates were identified using 23S rDNA primers as Streptomyces labedae (SB-9), Streptomyces flavofuscus (SA-11), and 16S rDNA primers as Pseudomonas poae (KA-5), and Pseudomonas fluorescens (KB-7). Influence of Glomus intraradices (G.I.) singly and along with actinomycetes and Pseudomonas spp. were evaluated under irrigated and water deficit conditions. Out of eight treatments studied in this study, a higher significant increase in plant height with S. labedae SB-9 + G.I and P. poae KA-5 + G.I were recorded. In well watered and water deficient conditions, maximum shoot dry matter content was recorded in P. Poae + P. flurosence + G.I and S. labedae + S. flavofuscus + G.I inoculated plants in comparison to their respective control. Under in vitro condition, P. poae KA-5 produced higher amount of indole acetic acid (IAA) among the selected isolates. Anti-oxidant enzyme, superoxide dismutase (SOD) and accumulation of free proline content in leaves were maximum in P. Poae + G.I inoculated plants under water deficit condition. In the presence of Streptomyces and Pseudomonas spp. a better mycorrhizal infection was observed in treated plant roots. This investigation support mutual symbiosis of Streptomyces and Pseudomonas strains with G. intraracides which had synergic effect on finger millet cv. Korchara plant under irrigated as well as under water stress condition.

Key words: Glomus intraradices, Streptomyces, Pseudomonas, anti-oxidants, plant growth promotion, IAA production

Abbreviation

SOD, Superoxide dismutase; G.I., Glomus intraradices; VAM, vesicular arbuscular mycorrhiza; AMF, arbuscular mycorrhiza fungi; MHB, mycorrhiza helper bacteria; H₂O₂, hydrogen peroxide; CAT, catalase; GPX, guaiacol peroxidase; APX, ascorbate peroxidase; PGPR, plant growth promoting rhizobacteria; IAA, indole acetic acid; CAS, chrome azurole S; NBT, nitro-blue tetrazolium; PVK, Pikovaskaya medium.