Uptake of humic substances

The assertion that humic substances can have a direct effect on 

Although this report demonstrated that HA could move along vascular bundles slowly and stain the cell walls of xylem parenchyma, it did not show that the humic material could be taken up by roots. 

Most investigations into the uptake and incorporation of humic 

Using C -labelled material. Prat and Pospisil showed that HA 

Furthermore, only a small fraction of the radioactivity was transported 

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