When this opuntia's (most likely stricta) flower is disturbed, it rapidly pulls all disturbed anthers towards the pistil and in the process self-pollinates. I just noticed this today and I'm amazed, what could possibly be the reason for it to do this? Normally cacti avoid self-pollination/fertilization. Anthers return to their normal position once the flowers is left alone.
https://i.imgur.com/SHGe2E3.mp4
Edit: My theory, when any insect land on the flower, it starts crawling down to get to nectar. Meanwhile the anthers all close up like in my video, so now when it crawls back up, it will get coated in a lot of pollen.
Rapid plant movement in Cacti
- One Windowsill
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Re: Rapid plant movement in Cacti
I would say your theory is probably correct.
It is an example of thigmonasty, various plant responses to touch. Many cactus flowers have this, including Notocactus, opuntioids (Opuntia and Puna, definitely), Pediocactus and Pterocactus.
Here are some videos:
https://www.youtube.com/watch?v=cag90Fp6bgs
https://www.youtube.com/watch?v=Hd1Ci2NC-FY
https://www.youtube.com/watch?v=FjV--NPPjlU
https://www.youtube.com/watch?v=TzkQ2NxLpec
It is an example of thigmonasty, various plant responses to touch. Many cactus flowers have this, including Notocactus, opuntioids (Opuntia and Puna, definitely), Pediocactus and Pterocactus.
Here are some videos:
https://www.youtube.com/watch?v=cag90Fp6bgs
https://www.youtube.com/watch?v=Hd1Ci2NC-FY
https://www.youtube.com/watch?v=FjV--NPPjlU
https://www.youtube.com/watch?v=TzkQ2NxLpec
Re: Rapid plant movement in Cacti
How awesome, just when you think you can't possibly love cacti more than you already do, they prove you wrongOne Windowsill wrote: ↑Sun Jun 13, 2021 12:23 pm I would say your theory is probably correct.
It is an example of thigmonasty, various plant responses to touch. Many cactus flowers have this, including Notocactus, opuntioids (Opuntia and Puna, definitely), Pediocactus and Pterocactus.
Here are some videos:
https://www.youtube.com/watch?v=cag90Fp6bgs
https://www.youtube.com/watch?v=Hd1Ci2NC-FY
https://www.youtube.com/watch?v=FjV--NPPjlU
https://www.youtube.com/watch?v=TzkQ2NxLpec
Re: Rapid plant movement in Cacti
As you say it is usually to coat the nectar drinking insect in pollen in order to carry it to pollinate the next flower. In many flowers the stigma is only receptive before its own pollen sacks burst in order to prevent self pollination, or in self fertile plants to delay self pollination so it can outcross with another plant if possible? If it was in order to self pollinate it would move the anthers in to the stigma automatically rather than needing the stimulus of an insect to cause the movement?
See also:-
https://awkwardbotany.com/2015/06/10/ye ... kly-pears/
https://www.britannica.com/science/poll ... ationfirst
See also:-
https://awkwardbotany.com/2015/06/10/ye ... kly-pears/
https://www.britannica.com/science/poll ... ationfirst