Isolation and Characterization of a Phosphate-Solubilizing Halophilic BacteriumKushneriasp. YCWA18 from Daqiao Saltern on the Coast of Yellow Sea of China

Abstract

Phosphate-solubilizing bacteria (PSB) function in soil phosphorus cycle, increasing the bioavailability of soil phosphorus for plants. Isolation and application of salt-tolerant or halophilic PSB will facilitate the development of saline-alkali soil-based agriculture. A moderately halophilic bacterium was isolated from the sediment of Daqiao saltern on the eastern coast of China, which also performs phosphate-solubilizing ability. The bacterium was assigned to genus Kushneria according to its 16S rRNA gene sequence, and accordingly named as Kushneria sp. YCWA18. The fastest growth was observed when the culturing temperature was 28°C and the concentration of NaCl was 6% (w/v). It was founds that the bacterium can survive at a concentration of NaCl up to 20%. At the optimum condition, the bacterium solubilized 283.16 μg/mL phosphorus in 11 days after being inoculated in 200 mL Ca3(PO4)2 containing liquid medium, and 47.52 μg/mL phosphorus in 8 days after being inoculated in 200 mL lecithin-containing liquid medium. The growth of the bacterium was concomitant with a significant decrease of acidity of the medium.

Phosphate Solubilizing Microbes: An Overview

“…(Wani et al 2005), Azotobacter (Kumar et al 2001), Xanthomonas (De Freitas et al 1997), Enterobacter, Pantoea, andKlebsiella (Chung et al 2005). Several halophilic bacteria Kushneria sinocarni have also been isolated from the sediment of Daqiao saltern on the eastern coast of China, which may be useful in stress conditions; salt affected agricultural soils (Zhu et al 2011). Among the whole microbial population in soil, PSB constitute 1 to 50 %, while phosphorus solubilizing fungi (PSF) are only 0.1 to 0.5 % in P solubilization potential (Chen et al, 2006) which includes Penicillium and Aspergillus, Rhizoctonia solani, Trichoderma.…”

Effects of phosphate-solubilizing bacteria application on soil phosphorus availability in coal mining subsidence area in Shanxi

“…Phosphate-solubilizing bacteria (PSB) play a crucial role in soil P solubilization (Abd-Alla 1994), increasing the bioavailability of soil P for plants (Zhu et al 2011). PSB can transform insoluble P to available P in the soil, so as to improve fertilizer use efficiency and crop yield (Hao et al 2006;Jiang et al 2012;Hu et al 2012).…”

Isolation and characterization of phosphate solubilizing bacteria (Klebsiella oxytoca) with enhanced tolerant to environmental stress

“…Though, there are some information regarding the stress tolerant PSMs such as Rhodotorula sp., PS4 is highly tolerant to temperature, pH and salt variations (Mundra et al, 2011); Kushneria sp. YCWA18 is tolerant to salt conditions (Zhu et al, 2011); Bacillus megatherium is tolerant to salt conditions (Xiang et al, 2011); Burkholderia vietnamiensis M6 is tolerant to temperature, pH and salt conditions (Park et al, 2010), and Pantoea agglomerans R-42 is tolerant to temperature, pH and salt conditions (Sharan et al, 2008;Son et al, 2006); most of the previously isolated PSMs are reported to perform poorly under stress conditions making them less appropriate for such environments. In this context, PSMs with the genetic potential for increasing tolerance to high temperature, pH and high salt concentration are still considered to be important for the establishment, multiplication and production of environmentally friendly bio-inoculants.…”