The objective of this work was to study the effects of aqueous extracts of Bermudagrass structures (Cynodon dactylon (L.) Pers) and soil exudates, on the germination and initial growth of rice, corn and wheat seedlings. The aqueous extracts of above-ground and subterranean parts and of the whole plant, as well as of stolons, leaves + culm, stolons + leaves + culm, rhizome, root and rhizome + root of Bermudagrass, were prepared from 100 g L-1 of dry plant material. It was also investigated if these extracts and the one obtained from soil removed from the rhizosphere of the subterranean plant parts, and of the stolons would show any interference. Inhibition or stimulation of the initial seedling development was dependent on the tested species and the structure employed in the preparation of the extract. Radicle protrusion was inhibited more than radicle and plumule growth. The stimulus of radicle and plumule growth was more evident when the extract was prepared from the root system structures, above-ground plant parts and whole plant than from the separated plant structures of Bermudagrass. Rice and corn were more inhibited by extracts prepared from the above-ground and subterranean plant part respectively. Wheat inhibition or stimulation effects were dependent on the variable analysed. The development of radicle and plumule of rice, corn and wheat was stimulated by extract prepared from the whole plant. The extract prepared from the clay + silt soil fraction in which the grass grew stimulated growth of corn radicle and wheat plumule.
allelopathic potential; Cynodon dactylon; Oryza sativa; Zea mays; Triticum aestivum
