Abstract
The hydroxamate siderophores ferrioxamine B (FOB) and the pseudobactin siderophores st3 (PSBst3) and 7NSK2 (PSB7nsk2) were evaluated as iron (Fe) sources to cotton (Gossypium herbeceum) rhizosphere bacteria. About 13% of the total bacterial CFUs were able to utilize FeFOB as the sole Fe source in an Fe-deficient medium, as compared to 1.6 and 2.6% being able to utilize the chelated Fe supplied as Fe-pseudobactins St3 and 7NSK2, respectively. Cotton plants grown in soil amended with 55Fe-EDDHA had about ten times more Fe in their leaves than when supplied with 55Fe-PSBst3. In a treatment in which the cells of strain 3 (St3) were added to the soil, about twice as much radioactivity was associated with the roots (on a gram fresh weight basis) of plants irrigated with PSBst3 than in the non-inoculated control treatment. These data suggest that pseudobactin is intrisincally a less available source of Fe to microbes than FOB and that the composition of the bacterial population of the rhizosphere may play an important role in transport and mobilization of Fe in this environment.
| Original language | American English |
|---|---|
| Pages (from-to) | 2183-2192 |
| Number of pages | 10 |
| Journal | Journal of Plant Nutrition |
| Volume | 15 |
| Issue number | 10 |
| DOIs | |
| State | Published - 1 Oct 1992 |
Bibliographical note
Funding Information:This reaserch was made possible by a grant from the U.S.-Israel Binational Agricultural Research and Development Fund (BARD).