In general, plants are chlorophyll-containing autotrophs. In some very rare cases, however, a plant is able to carry on its activity without the use of chloroplasts. These plants are classified as parasitic plants and they obtain nutrients, water, and minerals from host plants through the use of extensions called haustoria. These peg like extensions bore into the host plant and come into contact with the inner tissues in order to tap the plants nutrient/water flow. Plants that depend entirely on this form of nutrient absorption are known as obligate holoparasites, as opposed to the partially parasitic hemiparasites. .
While there are many different types of parasitic plants, I will focus on one in particular- The Dodder. This plant is an obligate holoparasite and is of great significance in the agricultural community.
The Dodder is a parasitic herb composed mainly of twining yellow-orange stems and clusters of small (3mm), waxy, pinkish-white flowers (Watson and Dallwitz, 2000). There are many species generally known as dodders, but there is some disagreement on the genus classification. Some will classify all species as the Genus Cuscuta, while others will split the species in to two genera, Cuscuta and Grammica, based on the shape of the stigma (Swift 1996).
The nature of this plant has engendered numerous descriptive names through the ages. It has been known as love vine, strangleweed, pull-down, hellbine, Beggarweed, hairweed, devil's-hair, devil's-guts, devil's-ringlet, goldthread, hailweed, and several more similarly unflattering names. According to the Ancient Pathway (2001), the dodder has magical properties as an herb. This, and its tendency to leach the life from its host plants, helps to explain the variety of names given to this plant.
As a parasite, the dodder attacks many types of plants including the chrysanthemum, dahlia, helenium, Virginia creeper, trumpet vine, English ivy, petunias, alfalfa, lespedeza, flax, clover, and potatoes (Swift 1996).
