Cistanche tubulosa

Taisha is the author for this entry.

Today’s photo is of Cistanche tubulosa. It was taken by Ton Rulkens (aka tonrulkens@Flickr) in its natural habitat on a beach near Chocas- Mar (Mossuril District) in northern Mozambique. Thank you Ton for the picture!

Cistanche tubulosa (Orobanchaceae) is an obligate parasite, meaning it relies on a host plant to complete its life cycle. For Cistanche tubulosa, the host plant is often a species that grows in coarse, sandy soils under dry, arid conditions. The germinated seedlings of Cistanche tubulosa lack the tissues of typical eudicot seedlings, such as the radicle (embyronic root), hypocotyl (embryonic stem) and cotyledons (embryonic leaves). Instead, the germinating embryo develops a tube-like organ that comes into contact with the root of the host plant, penetrates it, and forms the primary haustorium. Once it reaches the central core of root xylem of the host plant, the haustorium replaces the metaxylem cells and ensures physical support and nutritional supply for the parasitic Cistanche tubulosa plant. Collectively, the haustorial cells can look pith-like (despite roots being devoid of a pith) due their likeness to parenchyma cells. The tube-like organ that remains exterior to the root develops into a tubercle, which later differentiates into the stem of the parasite. This stem develops underground in the late summer or autumn. It will remain dormant until spring or summer, then eventually project above ground to reveal the spiked inflorescence. After seed set and release, the inflorescence first withers (usually within 2-3 weeks), followed by the underground stem. It is thought that the remaining stem below the withered spike may redevelop the following spring (see: Ilahi, I., et al. 2010. Cistanche tubulosa (Schenk) R. Wight an important medicinal plant occurring in sand dunes of Karak, N.W.F.P., Pakistan. Pakistan Journal of Botany. 42(1):537-547).

This fleshy herbaceous species is distributed in northern Africa, Arabia, and western Asia to Pakistan, India and central Asia. It grows anywhere from 15-150cm tall, but typically between 30-60cm. As the stem and leaves both lack chlorophyll, it can be also classified as a holoparasite (meaning it relies entirely on the host plant for photosynthates). The alternate leaves, in the form of scales, are arranged spirally around the stem. These scales have no well-developed stomata, instead relying on hydathodes for gas and water exchange. The flowers are bluish or crimson-coloured when young, but turn white, yellow or purplish-yellow at maturity.

Cistanche tubulosa

11 responses to “Cistanche tubulosa”

  1. Jane / MulchMaid

    There’s something so fascinating about parasites. This one is great!

  2. Douglas Justice

    This may be its natural habitat (as stated above), but not its natural ecology if the opuntia pictured is its host. Opuntia is a New World genus. Fascinating plant, and well described.

  3. Denis

    As with Douglas, I noticed the Opuntia. This may have just been a passing photo, but perhaps it was taken while the plant was being studied. Was there any information available as to whether it was using the Opuntia as a host? Or was there another, more compatible host nearby?

  4. liz

    I see the Opuntia too Is it the host?

  5. Jessica

    That is one wild and craaaazy plant. Very beautiful, in a creepy sort of way.
    Thanks for all the description of this fascinating parasite.
    Hey, everybody’s gotta make a living somehow.
    🙂

  6. Lewis H

    Is it using the Opuntia as the host?
    Or perhaps it is utilising another plant nearby?
    Here in Australia some of our native mistletoes which are usually found on eucalypts have adapted to using a range of exotic trees (including deciduous) as hosts.

  7. Ton Rulkens

    When I made the pictures I noted the large stands of Opuntia. Those introduced American plants often grow in Mozambique in a naturalized state (seeds spread by birds?). I will have a look at my other pictures, to draw some conclusions about the possible host plant

  8. Dana D

    I was at a Native (U.S.) Plant Conference last week and one speaker mentioned Dodder as being native and attracting butterflies. I wonder if Cistanche tubulosa also may become part of the ecosystem by attracting some sort of insect.

  9. Wendy McClure

    Reminds me of Orobanche pinorum which is parasitic on Holodiscus in the Pacific Northwest.

  10. Daniel Mosquin

    I had a quick look into what genera it might parasitize, and it seems to have a broad range of hosts (as Douglas Justice suggested to me in a hallway conversation). These include: Calitropis (Apocynaceae) and Acacia (Fabaceae) with this species. Other species in the genus (and perhaps this one) are observed to parasitize Tamarix (Tamaricaceae) and Haloxylon (Amaranthaceae). So, perhaps that Opuntia is being parasitized.

  11. S.Mason

    since opuntia is non-native to Africa, and often a pest, it’s unlikely to be a host plant. Orobranche seems in fact rather similar to squaw root in north america

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