Rhizosphere continued microorganisms

Phytotoxins synthesized in the rhizosphere by microorganisms may play a greater role in plant growth than those derived from the breakdown of crop residues. This is chiefly because the rhizosphere flora feeds on a continuous supply of exuded food that is especially suitable for antibiotic-producing microorganisms. The antibiotics produced ... 

Organic compounds released from sloughed-off root cells and tissues are a major carbon source for rhizosphere microorganisms but may indirectly have an impact as microbial metabolites on nutrient availability and on exclusion of toxic elements in the rhizosphere (Brimecombe et al., 2007). Continuous root turnover is a general feature of plant development, and insoluble root debris may comprise 50-90% of total rhizodeposition (Darrah, 1991). 

In the rhizosphere, the presence of hiomolecules continuously released hy plants as root exudates or microorganisms play a crucial role in the dynamics and bioavailability of metals and metalloids for plants and biota. The influence of biomolecules as well as of biotic and abiotic components on trace elements transformation and mobility deserves to be studied with particular attention. 

---