In order to be efficient, the crop rotation system requires, among other factors, an adequate choice of species to be installed. Vegetal cultures can feature allelochemical compounds, released by root hairs, roots, stems and leaves in variable amounts, which are able to interfere on subsequent cultures, as well as cause a delay in their production. Thus, this study analyzed the allelopathic potential of black oat (Avena strigosa Schreb) (BO), forage turnip (Raphanus sativus L.) (FT), vetch (Vicia sativa L.) (V), ryegrass (Lolium multiflorum Lam.) (RG) and consortium (CO - BO+V+FT) on soybean seed germination and plantlet growth. This trial was carried out in a laboratory, with sand substrate, where coverage plants were grown, during 30 days. The remaining root portions of plants were kept with and without the remaining aerial part portions. A reduction was observed on the emergence of soybean plantlets under CO, RG and BO. The emergence speed index (ESI), emergence percentage on sand (ES) and the green mass of hypocotyls (GMH) were negatively affected by coverage plants, and due to this, another study is essential to verify whether there is an indication of the allelopathic effect.
crop rotation; winter-season culture; allelopathy
