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 Plants
 Pollen Tube Growth

I used Stargazer lilies, but I think any lily would do. I selected pollen from a variety of sources, like fresh flowers...

Pollen Tube Growth Lab

And I also selected pollen from mature flowers. I think this older pollen sprouted better, but you should experiment for yourself.

Pollen Tube Growth Lab

The epidermis of onions (that thin layer of cells that peels away between layers of onion bulb) was removed in strips and laid with inner side facing upwards on microscope slides. Pollen was dabbed onto the exposed inner surface of the onion epidermis and then a wet mount was made (water plus coverslip). The slides were placed and kept in a humid box lined with moist paper towel. I just used a Chinese food container with a cover. I kept them there for the day. The pollen tube growth shown in photos below was seen by end of day (4 hours of elapsed time)

Pollen Tube Growth Lab

Isn't that just so cool!!

Pollen Tube Growth Lab

In 2009, I tried Amaryllis and was equally successful. Sometimes I get more pollen tube growth than others, but whenever I get a student who says, "I can't find any.", I take a look, turn the light down via the diaphragm, and I can always find some within a minute. Try looking along the edges of the coverslip. This year I found more germination there than in th center of the slide, so keep looking!
Pollen Tube Growth Lab

Pollen Tube Growth Lab

Pollen Tube Growth Lab

Pollen Tube Growth Lab

Pollen Tube Growth Lab

Do you think we are seeing two sperm nuclei here???

Pollen Tube Growth Lab

Do you think we are seeing two sperm nuclei here???

Pollen Tube Growth Lab







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