Figure 1.

Some representative parasitic plant species. (a) Triphysaria versicolor, a hemiparasite, a photosynthetically competent species that, facultatively, parasitizes roots of neighboring plants; (b) Orobanche cumana, holoparasite, with absolute nutritional dependence on a host, mainly parasitizes roots of sunflower; (c) Cuscuta pentagona, holoparasite, also known as dodder, that parasitizes aboveground tissues of both monocot and dicot hosts; (d) Striga gesnerioides, an obligate hemiparasite that mainly parasitizes roots of cowpea.