Allelopathic potentials of traditional Chinese medicinal plant spp.

China has rich plant biodiversity and many plants show bioactivities on human and animals. Allelopathic studies on traditional Chinese medicinal plant species have started recently. Twenty three traditional Chinese medicinal plant species were selected to test their allelopathic activities on wheat and cucumber. The allelopathic activities of S. alopecuroides, C. komarovii, V. officinalis, R. officinale, R. glutinosa, C. komarovii, S. nux-vomica and L. lucidum on plants are reported first time on agricultural pests. The extract from L. radiata drastically inhibited (> 90%) the growth of monocotyledon and dicotyledon plants, its inhibitory effects stopped the germination of wheat and cucumber seeds. C. komarovii and C. hederacea plants extracts were most inhibitory (>80%) to root growth of both monocotyledon and dicotyledon plant roots. C. komarovii also inhibited the plant shoot elongation. The other plant species with higher allelopthic activity only inhibited either monocotyledon or dicotyledon plants. Fourteen plant species inhibited the growth of monocotyledons, but only 3 plants spp. (L. radiata, Artemisia scoparia and C. komarovii) were inhibitory to the root and shoot growth of dicotylecon plants. Extracts of R. glutinosa, L. radiata, A. scoparia, L. lucidum, C. ambrosiodes and S.nux-vomica strongly inhibited the shoot length of endosperm removed wheat seedlings, indicating that the extracts might inhibit the photosynthesis. The traditional Chinese medicinal plant spp. possess numerous allelochemicals with different mechanisms and selectivity. This study clearly demonstrated that the medicinal plant species are potent sources of allelochemicals, which could be used for sustainable weed management and ecofriendly environment.