SUBJECT: Plant physiology/transpiration experiments
DATE: 12/95

Hopefully some one has a creative solution to one of my continuing problems...
In our Fundamentals series, we use geranium cuttings to do a transpiration
experiment. We compare water loss under various conditions (wind, light,
and combination). Unfortunately, the greenhouse where I had been keeping
the donor plants is being taken over for research- no sad little geraniums
allowed! So, I can either buy geraniums every year and use them only once
or come up with some alternative. Obviously, buying geraniums is a drain
for a single lab.

Can anyone suggest alternatives for a basic plant phys lab? We do a plant
anatomy lab and a hormone lab later. I'd appreciate any suggestions.

On a different note, does anyone have a wholesaler for aquarium/ small
animal supplies that will deal with schools? There was one that I used in
Cleveland but they won't deliver orders under 200$.

Thanks,
Brenda Simmers
Lab Coordinator
Dept. of Biology
University of Toledo



Brenda,
I have done similar transpiration experiments using tobacco and tomato
plants- both work fairly well. A plant that really works great is a house
plant called Calladium (also called nerve plant). It has a large blade,
long petiole, and really transpires rapidly. It's available at grocery
stores, etc.

+ - - - - - - - - - - - - - - - - - - - - - - - - - - +
+ Ed Alkaslassy (503) 359-2967 +
+ Dept. of Biology FAX: 503-359-2933 +
+ Pacific University <alkaslae@pacificu.edu> +
+ Forest Grove OR 97116 +
+ - - - - - - - - - - - - - - - - - - - - - - - - - - +


The AP lab book uses bean plants for a tranpiration experiment. They can be
grown in a few weeks so you don't need the greenhouse space for very long.

We used to use an ornamental shrub called redtip (Photinia) here at Clemson.
It doesn't grow in Toledo, but you might find some other plant that is
suitable and abundant at the time of year it's needed (we clipped enough
branches for 1200 students, so it is possible).

We also used potatoes and apples to demonstrate protection (or lack) against
water loss. They were weighed before and after different treatments.

Other ideas for a plant phys experiment? If you have light available mineral
nutrition is always fun. When I was a TA we did a neat experiment on the
effect of ABA on transpiration of wheat seedlings but that also required
having light available.

Jean Dickey
dickeyj@clemson.edu


Brenda: In our first-year biology transpiration experiments, I have
found that we get the best results with clipping branches of cedar,
fir or spruce trees. These are incredibly tough, and with white cedar
in particular have a fast rate of transpiration even when brought in
from well below freezing temperatures (in January) to a warm lab. One
cedar branch can be used several times (and often is still transpiring
rapidly a week later!) if the end is kept under water. Clippings do
not need to be very large. Our source is any evergreen trees in the
campus woodlot.
I hope this is helpful!
Lucy Dyer (Biology Department, University of New Brunswick).


Brenda/Others:

Alan Dickman does a transpiration experiment using evergreen (usually fir
or pine) and deciduous (usually a big leaf maple that is leafed out)
cuttings from trees around campus. He gets the okay from the grounds crew
to take enough cuttings for class without mangling any one tree. Students
then design their own experiments using variables such as air flow (fans),
light, temp., etc.

Stacey

******************************************************************
@ Stacey Kiser Good judgment comes from
@ Research Assistant experience, and often
@ Workshop Biology experience comes from bad
@ Department of Biology judgment.
@ 1210 University of Oregon
@ Eugene, OR 97403-1210 Rita Mae Brown
@ phone (503) 346-5092
@ fax (503) 346-6056

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