Why are seagrasses all monocots?

Question

I have been looking for the answer to this question for a while now. I know it has to do with how the seagrass deals with salt (morphocially, anatomically, etc.) and for some reason dicots cannot achieve this.

Thanks

Answer 1

I'm not sure if/how this is related to monocots but I've found this information:

"Seagrass salt tolerance is due to their maintaining a lower water potential in their cells than the surrounding salt water. They do this by accumulating sodium in the cell vacuoles. Recently, scientists discovered a salt tolerance gene that codes for a transport protein that carries sodium into the vacuole. The salt tolerance gene has been transferred into tomato plants thus making them salt tolerant."

Sea grasses also contain aerenchymatic tissue in their leaves/roots, presumably to aid gas exchange and overcome the anoxic conditions underwater. Some sea grasses, like Zostera, are nitrogen fixing too.

Perhaps you would like to read more of this book, it's the most comprehensive source on sea grass that I was able to find online.

http://books.google.com.au/books?id=emkD...

Monocots are certainly the dominant marine plants, I couldn't tell you if this were just coincidence or what but it's certainly an interesting question you raise.

Answer 2

If you're statement that all seagrasses monocots is true...

Its just tell us that monocot has very advanced features in thriving on salty environment. It must related for the salt excreting process of them that made them well adapated to live on sea.

Answer 3

Great question(s). It looks like you can access good parts of the following book dedicated to seagrasses through the Google Books function:

http://books.google.ca/books?id=emkDvfaz...

You might also want to visit:

http://www.eoearth.org/article/Seagrass_...