Growth promotion of wheat seedlings by Exiguobacterium acetylicum 1P (MTCC 8707) a cold tolerant bacterial strain from the Uttarakhand Himalayas

Abstract

Exiguobacterium acetylicum strain 1P (MTCC 8707) is a gram-positive, rod-shaped, yellow pigmented bacterium isolated from soil on nutrient agar plates at 4°C. The identity of the bacterium was arrived on the basis of the biochemical characterization, BIOLOG sugar utilization pattern and sequencing of the 16S rRNA gene. It grew at temperatures ranging from 4 to 42°C, with temperature optima at 30°C. It expressed multiple plant growth promotion attributes such as phosphate solubilization, indole acetic acid (IAA), siderophore and hydrogen cyanide (HCN) production, differentially at suboptimal growth temperatures (15 and 4°C). At 15°C it solubilized phosphate (21.1 μg of P ml -1 day -1 ), and produced IAA (14.9 μg ml -1 day -1 ) in tryptophan amended media. Qualitative detection of siderophore production and HCN were possible at 15°C. At 4°C it retained all the plant growth promotion attributes. Seed bacterization with the isolate, positively infl uenced the growth and nutrient uptake parameters of wheat seedlings in glass house studies at suboptimal cold growing temperatures.

Characterization of plant growth-promoting rhizobacterium Exiguobacterium NII-0906 for its growth promotion of cowpea (Vigna unguiculata)

“…Important contributing feature of NII-0906 was the increased P-solubilization, which was four times higher than that of any other Exiguobacterium species. Selvakumar et al (2008) reported 22.6 ± 2.16 µg/mL per day of P-solubilization at 30…”

Novel plant growth promoting rhizobacteria—Prospects and potential

“…Further it is also been reported to increase the growth and nutrient uptake of wheat seedlings under glass house conditions (Selvakumar et al, 2010). Phosphate solubilizing Exiguobacterium strains were isolated from acidic soils of Argentina (Collavino et al, 2010) and paddy fields of Eastern Uttar Pradesh in India (Kumar et al, 2010).…”

Prospecting cold deserts of north western Himalayas for microbial diversity and plant growth promoting attributes

“…Several bacteria support plant growth indirectly, via production of antagonistic substances or by inducing resistance against plant pathogens (7,10,11). By producing plant growth regulators, these organisms are reported to influence seed germination and seedling growth (7).…”