Genotype and harvest time affect the allelopathic activity of Cynara cardunculus L. extracts on Amaranthus retroflexus L. And Portulaca oleracea L.

1. Scavo, A.
2. Pandino, G.
3. Rial, C.
4. Varela, R.M.
5. Molinillo, J.M.G.
6. Macias, F.A.
7. Mauromicale, G.