Image 1 - Longitudinal section view of an amaryllis leaf showing helical tracheal elements passing from upper left to lower right diagonally. To the upper right are vacuoles that contain what I believe to be chloroplasts bunching up to one side.
Image 2 - Longitudinal section view of an amaryllis leaf showing helical tracheal elements. Sloppy work in cutting has ruptured one of the tracheids causing it’s helical wall thickenings to spill out.
Image 3 - Longitudinal section view of an amaryllis leaf showing a more flattened view of the helical tracheal elements. This view shows a interesting feature of the elements. From left to right, the tightness or compression of the helix coil is seen to increase a little more on each tracheid. At the top of the image, all six of the elements can be seen. Two partially.
Image 4 - Transverse section view of an amaryllis leaf showing the severed ends of six tracheal elements. Look for the six complete circles left and below center.
Image 5 - Transverse section view of an amaryllis leaf showing the severed ends of six tracheal elements. The torn cut at the location of the termination point has caused the helical coils to spill out onto the surface. Above center.
Helical Tracheary Elements
I have no formal education in botany, but it doesn't stop me from putting a plant under the microscope. In a recent study of a amaryllis leaf I ran across something I had read about in a text book on plant biology. I had taken the bold move of making a longitudinal section of the leaf and was delighted to find some spring coil like features. These turned out to be tracheary elements or tracheids. Tracheary elements are the conducting cells of the plant xylem and carry water and minerals up through the plant. They can even provide support for stems as they are rigid thanks to the lignin in their walls.
I have labeled the tracheids in my images as having helical wall thickenings, but they can also be annular, scalariform, and pitted in construction. All forms I look forward to seeing in the future.
Image three is a real puzzle to me regarding the different coil compression factors. Even more interesting is how they tighten, left to right. Some readings on the subject say that the loose coil on the left shows an immature tracheid. The one to the far right a mature one. Other readings explain the difference as an amount of stretching due to growth, yet they are side by side? They are bunches of six as far as I have seen. Whatever the reason, its been a learning experience I wanted to share.
Walt
Leitz Ortholux, Canon 50D,
Leitz UO 50x Apo., Horizontal F.O.V. approx. 200 microns on all images.
Zerene Stacker, PhotoShop
Interesting.
