Isolation and identification of allelochemicals and their activities and functions

Abstract

Allelopathy is the interaction between donor plants and receiver plants through allelochemicals. According to a great number of publications, allelopathy may be involved in several ecological aspects such as the formation of monospecific stands and sparse understory vegetation for certain plant species. Allelopathy also contributes to the naturalization of invasive plant species in introduced ranges. Autotoxicity is a particular type of allelopathy involving certain compounds. Many medicinal plants have been reported to show relatively high allelopathic activity. We selected plant species that show high allelopathic activity and isolated allelochemicals through the bioassay-guided purification process. More than 100 allelochemicals, including novel compounds have been identified in some medicinal and invasive plants, plants forming monospecific stands, plants with sparse understory vegetation, and plants showing autotoxicity. The allelopathic activity of benzoxazinones and related compounds was also determined.

Keywords: allelopathy; autotoxicity; invasive plant; medicinal plant; monospecific stand; phytotoxicity.

Fig. 1. Allelochemicals of neem.

Fig. 2. Allelochemical of Aglaia odorata.

Fig. 3. Allelochemical of ginkgo.

Fig. 4. Allelochemical of Orthosiphon stamineus.

Fig. 5. Allelochemicals of Marsdenia tenacissima.

Fig. 6. Allelochemical of Garcinia xanthochymus.

Fig. 7. Allelochemical of Wedelia chinensis.

Fig. 8. Allelochemicals of Albizia richardiana and Elaeocarpus floribundus.

Fig. 9. Allelochemicals of Hypnum plumaeforme.

Fig. 10. Allelochemical of Dicranopteris linearis.

Fig. 11. Allelochemicals of Gleichenia japonica.

Fig. 12. Allelochemicals of Schumannianthus dichotomus.

Fig. 13. Allelochemicals of Japanese red pine.

Fig. 14. Allelochemical of Citrus junos.

Fig. 15. Allelochemicals of Pueraria montana.

Fig. 16. Allelochemicals of Imperata cylindrica.

Fig. 17. Allelochemicals of Polygonum chinense.

Fig. 18. Allelochemical of Tithonia diversifolia.

Fig. 19. Autotoxic substances of asparagus.

Fig. 20. Autotoxic substance of kiwifruit.

Fig. 21. Benzoxazinones and related compounds.