Abstract

This research was aimed to investigate the application of weed species forphytoremediation of soil polluted with boron. A greenhouse experiment was conducted to study the effect of increasing boron (B) application on the growth and B uptake of common weed species, Sorghum halepense L. Pers., Cyperus rotundus L., Cynodon dactylon L. Pers., Amaranthus retroflexus L., Echinochloa Cruss-gali L. and Chenopodium album L. Four levels of B (0, 10, 20 and 30 mg kg^-1soil) were applied to six weed species. Results revealed that, shoot and root dry weight of species decreased with increasing B application. There was a considerable variation among weed species in terms of their responses to B applications. The species having rhizomes such as S. halepense, C. rotundus andC. dactylon Pers. were more tolerant to the B toxicity than species growing from the seeds of A. retroflexus, E. Cruss-gali and C. album. The shoots contained higher concentration of B than the roots. Boron content of weed species was notably different and was affected by B applications. The high aboveground biomass and B accumulation in the shoot of any of weed species used in the experiment cannot be considered a potential parameter for the phytoextraction of B.

Key words: Boron toxicity, tolerance, dry weight, hyperaccumulator.