Abstract
Allelopathy of common lambsquarters (Chenopodium album) has been reported. It was found that crude extracts of plant leaves or residues have inhibitory activity to other plant germination and/or growth and that root exudates collected from the solution culture of lambsquarters also reduce other plant growth. So we assembled stairstep experiment apparatus, a sort of sand culture, connecting the pot with pipe so that root exudates of one plant can flow into another plant, and CRETS (continuous root exudates trapping system) and used them for the discrimination of allelopathy. The results showed that common lambsquarters cultivated in stairstep apparatus and CRETS inhibit the growth of cucumber plant. In both cases, the inhibition of upper part of the cucumber plant was more prominent than that of roots. These results show that growth-inhibiting effect of common lambsquarters in the mixed culture with cucumber plant is not attributed to the competitions for light and nutrients but to allelopathic interference. In CRETS test, XAD-4 resin could eliminate the inhibitory activity of common lambsquarters to cucumber plant. The crude extract of XAD-4 resin, to which the phenolic exudates of common lambsquarters was trapped, also contained plant growth-inhibiting activity. We concluded that common lambsquarters have an allelopathic potential by their root exudates.
