Growth stimulatory effect of Ochrobactrum intermedium and Bacillus cereus on Vigna radiata plants.
OBJECTIVE
This study assessed the plant growth-promoting ability of the bacterial strains Ochrobactrum intermedium (isolate CrT-1) and Bacillus cereus (isolate S-6).


RESULTS
Two chromium resistant bacterial strains isolated from chromium-contaminated wastewater and soils were identified as O. intermedium CrT-1 and B. cereus S-6. These strains were inoculated on seeds of mungbean Vigna radiata var NM-92, which were germinated and grown under chromate salts (300 microg ml(-1) of CrCl(3)or K(2)CrO(4)). The data show that Cr(VI) was more toxic because of its better availability to plants roots when compared with Cr(III). The major part of Cr(VI) supplied to the seedlings was reduced to Cr(III) in the rhizosphere by the bacterial strains, thus lowering the toxicity of chromium to seedlings.


CONCLUSIONS
Strains have significant Cr(VI) resistance and reduction potential and have ability to enhance mungbean plant growth under chromium stress.


CONCLUSIONS
These strains could be utilized for the growth of economically important cash crops as well as for the bioremediation of chromium-polluted soils.
Faisal
M
M
Department of Botany, University of the Punjab, Quaid-e-Azam Campus, Lahore, Pakistan.
Hasnain
S
S
D001409:Bacillus cereus / Q000187:drug effects / Q000235:genetics / Q000502:physiology*; D002857:Chromium / Q000737:chemistry / Q000633:toxicity; D024881:Drug Resistance, Bacterial; D007887:Fabaceae / Q000187:drug effects / Q000254:growth & development* / Q000382:microbiology; D006863:Hydrogen-Ion Concentration; D042041:Ochrobactrum / Q000187:drug effects / Q000235:genetics / Q000502:physiology*; D018517:Plant Roots / Q000187:drug effects / Q000254:growth & development / Q000382:microbiology; D012336:RNA, Ribosomal, 16S / Q000235:genetics; D036226:Seedlings / Q000187:drug effects / Q000254:growth & development / Q000382:microbiology
D012336:RNA, Ribosomal, 16S; D002857:Chromium