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  • Hi guys! As something of a belated Halloween episode, today I'm going to be talking about

  • a couple of really cool parasitic plants. When talking about parasitic plants, there

  • are a couple of terms that come in handy when describing these plants. The first pair of

  • these is facultative and obligate. A facultative parasitic plant can complete its life cycle

  • without its host, though it would prefer to have its host. An obligate parasite has to

  • have its host to complete its life cycle. A second pair of terms is holoparasite and

  • hemiparasite. Now a holoparasite has to no chlorphyll, meaning its completely reliant

  • on its host for nutrients. A hemiparasite, however, might have some chlorophyll, so it

  • can produce some of its own nutrients, but still needs its host.

  • So the first of the parasitic plants I'm going to talk about is a holoparaiste, and that's

  • the Albino Redwood, Sequoia sempervirens. Now most redwoods are large, normal trees

  • that have chlorophyll to produce their own nutrients. And albino redwood is a mutant

  • that doesn't contain chlorophyll, which is why its leaves look like this. And it because

  • it doesn't contain chlorophyll it can't create its own nutrients. As a solution, albino redwoods

  • graft their root systems onto the root systems of healthy redwoods so that they can gain

  • nutrients that way. There are only a handful of these albino redwoods known to exist, and

  • their locations are kept secret to keep them safe.

  • Now a parasitic plant you might not normally think of is mistletoe. Mistletoe describes

  • a lot of plants, but one specific example is Viscum album, European Mistletoe. Mistletoe

  • grows on the trunks of trees and absorbs its nutrients by leeching them from the tree.

  • They would also be a hemiparasite, because they do contain some chlorophyll to produce

  • their own nutrients. Mistletoe is actually poisonous because it contains viscumin, a

  • compound that inhibits protein synthesis in cells.

  • Now this last parasitic plant is a weird one. Its common name is Sandfood, but its scientific

  • name is Pholisma sonorae. Sandfood is a very rare flowering plant that grows in the deserts

  • of the western US. Only the plant's inflorescence, or flower, is visible above the sand level,

  • and its stems grows underground. This stem can be up to 6 feet, or 2 meters, long and

  • it reaches down through the ground to graft onto the root systems of neighboring shrubs.

  • This plant also does not have chlorophyll, as you can tell from this picture, it is not

  • green at all. This means it is also a holoparasite like the Albino Redwood.

  • Thank you for watching this quick video about parasitic plants. For more botanical content,

  • check out www.brilliantbotany.com. Don't forget to like and subscribe, thank you so much for

  • watching, and I will see you next time.

Hi guys! As something of a belated Halloween episode, today I'm going to be talking about

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寄生植物的奇怪世界 (The Weird World of Parasitic Plants)

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    稲葉白兎 發佈於 2021 年 01 月 14 日
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