RESUMO
Bacteria that enhance plant growth and development and are found in the vicinity of roots are referred to as plant growth-promoting rhizobacteria. Some beneficial bacteria help plant tolerance to many hazardous chemical elements. In this context, Cupriavidus basilensis , Novosphingobium humi , Bacillus zanthoxyli , Bacillus sp., Paenibacillus alvei , Ancylobacter aquaticus and Ralstonia syzygii metal-tolerant rhizospheric bacteria were isolated from rhizospheric soil associated with Bacopa monnieri . The beneficial effects of rhizospheric bacteria on B. monnieri plant physiology and biochemical responses were investigated under pot conditions at two levels (100µM and 500µM) of CuSO4 or FeCl3 . N. humi , A. aquaticus and R. syzygii bacterial strains were associated with significantly increased height and biomass under normal and stress conditions. An assay for indole acetic acid in isolated rhizospheric bacteria found differential secretion except Bacillus zanthoxyli . Bacoside A is a major phytocompound in B. monnieri with medicinal value; maximum induction was observed in the R. syzygii treatment. High concentration of copper and iron salts negatively influenced height, biomass and photosynthetic pigments; however N. humi , A. aquaticus , Bacilllus sp. and R. syzygii beneficial bacterial helped plants under stress conditions. Moreover, a significant enhancement in chlorophyll a and b was noticed in C. basilensis , B. zanthoxyli , Bacilllus sp., P. alvei and R. syzygii treatments, without much influence on carotenoid levels. Therefore, the present study emphasises the importance of isolating plant growth-promoting rhizobacteria for use in bacopa plants exposed to metals such as copper and iron in soil.
Assuntos
Bacopa , Gallionellaceae , Cobre/farmacologia , Ferro/farmacologia , Bacopa/química , Clorofila A/farmacologia , Bactérias , SoloRESUMO
Carbapenemase-producing Klebsiella pneumoniae is an emerging threat worldwide. The appropriate therapy for infections due to these multidrug-resistant pathogens is not well defined and depends upon the susceptibilities of individual isolates, and the choices are often severely limited. We report a case of a 8-year-old male child with ARDS with left-sided tubercular pleural effusion who developed ventilator-associated pneumonia due to multidrug-resistant Klebsiella pneumoniae treated successfully with a regimen comprising a combination of colistin and double carbapenem.