Hyobanche (Orobanchaceae) is a small genus of parasitic plants native to southern Africa. These plants are root parasites, attaching themselves to the roots of other plants and drawing water, mineral nutrients, and carbon from their host plants. Sometimes it’s hard to imagine that a plant can feed on another plant in this way, but there are many thousands of species in the plant kingdom that are parasitic.
There are different kinds of parasitic plants. Some can survive without a host plant, but do better if they are attached to another plant. These are called facultative parasites. Hemiparasitic plants can make their own food through the process of photosynthesis, but draw nutrients from their host plant. Hemiparasites have green leaves and, if they are root parasites, you might not even suspect they are parasitic. Holoparasites, in contrast, have no leaves, are not green, and depend entirely on their host plants for water, mineral nutrients, and the products of photosynthesis (i.e., reduced carbon). The family to which Hyobanche belongs, the Orobanchaceae, encompasses all of these strategies.
I started working on the systematics (evolutionary history and relationships) of Hyobanche in 1996, shortly after the end of the Apartheid era in South Africa. I’ve had nine field seasons in southern Africa to collect museum specimens, tissue samples, and to make ecological observations. My lab group is actively working on the population genetics, phylogenetics, and a variety of projects for this interesting genus.
Here are some images from last year’s field season in South Africa. I was collecting population samples of species of Hyobanche as well as host root tissue samples for a forensic analysis of the host range of this interesting parasitic plant. I’ll be posting more information and pictures as this blog develops.
Just for kicks here’s one of the videos I made from last year’s field season. This one is of a collection site for Hyobanche sanguinea.