Plant growth-promotion tests and organic pollutant
tolerance and degradation tests were conducted on all strains isolated in bioassay A), and on those
proving to be pure cultures from bioassay B). The selected landfill is described as are isolation and test
procedures. Results indicate that plants did not show toxicity symptoms when exposed to BaP but did
when grown in landfill soil. Some endophytes demonstrated plant growth-promotion capacity and
tolerance to BaP and other organic compounds (diesel and PCB commercial mixtures). A few strains may
even have the capacity to metabolize those organic pollutants. The overall decline in plant growthpromotion
capacity in those strains isolated from the landfill soil experiment, compared with those
from the bioassay with BaP, may indicate that lupin endophytes are not adapted to metal concentration
in roots and shoots and fail to grow. As a result, most isolated root endophytes must have colonized root
tissues from the soil. While preliminary degradation tests showed promising results (some strains
exhibiting the potential to use organic pollutants as their sole source of carbon), these are not conclusive
and further in-depth degradation assays need to be performed.