In recent years, the use of green manure in vineyards has increased significantly. Green manure has been shown to be effective in soil fertility maintenance and erosion control, increasing soil macro and microporosity by penetration and decomposition of roots, increasing organic matter levels, besides the possibility of reducing herbicide usage in vineyards. A number of cover crop species have been used without knowing the side effects they can cause to the grapevine and few studies have been conducted to assess these effects. The purpose of this study was to evaluate allelopathic effects of winter green manure species on the development of the grapevine rootstock VR 043-43. The experiment was arranged in a completely randomized design, with 19 treatments and 4 replicates. Extracts from the aerial part and roots of nine species used as winter green manure were evaluated for allelopathic effects. Rooted cuttings were planted in pots containing sand and were watered with an aqueous solution of each extract and fertilizer twice a week, for 45 days. After this period, the root length, root number per cutting, the fresh weight of roots and shoots were recorded. The results showed that among the species studied, the highest allelopathic effect was found for the extract of the aerial part of corn spurry (Spergula arvensis L.), followed by the extracts of the aerial part of dandelion (Taraxacum officinale L.). Rye (Secale cereale L.) and radish (Raphanus sativus L.) showed no allelopathic effect.
viticulture; allelochemicals; rooting
