Plants which feed on their hosts and keep them alive until they have completed their life cycle are known as parasitic plants. Approximately 3,900 flowering plant species belonging to 20 plant families have been recognized as parasitic plants. Mostly, the life cycle of parasite completes earlier than the one of the host plant which leads to a premature death of the parasitized plants.

Based on their dependency to complete life cycle, two categories of parasitic plants has been recognised, namely, obligate and facultative parasitic plants. Obligate parasitic plants rely totally on their hosts to complete their life cycle but facultative parasitic plants are able to survive on their own in the absence of their host plants.  Additionally, parasitic plants can be divided into hemiparasites that rely only partially on a host plant and are still able to make photosynthesis and holoparasites that are completely dependent on photoassimilates, solutes, and metabolites from their host plants. Further, they may be root parasites or shoot parasites due to their preferred target host organ.


  1. Westwood J. H., Roney J. K., Khatibi P. A., Stromberg V. K. (2009). RNA translocation between parasitic plants and their hosts. Pest. Manag. Sci. 65 533–539 10.1002/ps.1727
  2. Kaiser, B., Vogg, G., Fürst, U. B., & Albert, M. (2015). Parasitic plants of the genus Cuscuta and their interaction with susceptible and resistant host plants. Frontiers in Plant Science, 6, 45.