Allelopathic effects of leaf litters from four coniferous pure forests on three leguminous shrubs and grasses

In order to investigate the feasibility of leguminous shrub and grass species applied in coniferous artificial forests renovation and silvopastoral vegetation construction, allelopathic effects of different concentrations (10, 20 and 40 mgmL-1) of water extracts from decomposed leaf litters of P.tabulaeformis, P.orientalis, L.principisrupprechtii and P.sylvestris on seed germination and seedling growth of A.fruticosa, V.villosa and M.officinalis were studied. The results indicated that 1) P.tabulaeformis litter extracts inhibited the seed germination of V.villosa and M.officinalis, and showed the law of lowerstimulation and highinhibition on the seed germination of A.fruticosa and seedling growth of V.villosa; 2) P.orientalis litter extracts decreased the germination rate of V.villosa, and promoted seed germination of M.officinalis and the growth of V. villosa seedling and A.fruticosa radicals, and showed the law of lowerstimulation and highinhibition on the seed germination of A.fruticosa and the growth of A.fruticosa seedling and M.officinalis seedling; 3) L.principisrupprechtii litter extracts inhibited the seed germination of A.fruticosa and V.villosa, promoted the seed germination of M. officinalis and the growth of V.villosa seedling and M.officinalis radicals, and showed the law of lowerstimulation and highinhibition on the seedling growth of A.fruticosa; 4) P.sylvestris litter extracts showed the law of lowerstimulation and highinhibition on the seed germination of A.fruticosa, inhibited seed germination of V.villosa and M.officinalis and the seedling growth of A.fruticosa, while they could promote the growth of V.villosa seedling and A.fruticosa radicals, lower concentration extract promoted the seedling growth of M.officinalis significantly; 5) Analysis results of three leguminous shrub and grass seedlings MDA content and their seedling growth analysis results were consistent. MDA content might be the most sensitive indicator to measure the allelopathic effect.