Developmental and Structural Section
Huggett, Brett , Tomlinson, P. Barry .
Vessel length measured in situ in the aerial roots of epiphytic (Araceae).
We present a method of measuring vessel length in plant organs directly and in situ using digital photographic images translated into movies by computer software. This overcomes the disadvantage of traditional methods, such as paint and latex infusion, or blowing air through the organ under pressure, both of which require any vessel to be cut at one or both ends. Our method also looks at vessels directly so that vessel length in relation to other anatomical features can be measured. We have chosen the aerial roots of a number of epiphytic Araceae, Heteropsis, Monstera and Philodendron, which can descend from the canopy for many meters before reaching the ground, anchoring and branching, in order to begin upward transport of water through the xylem. These roots have wide medullary vessels and the length of all vessels visible at the magnification used can be measured. We proposed that roots growing without restriction in space could differentiate vessels of unlimited length. The method requires only a digital camera attached to a compound or dissecting microscope and appropriate computer software. Photographs can be taken of freehand sections or smoothly cut surfaces at low magnification. Overlapping vessel ends can easily be distinguished from oblique perforation plates by their much greater length. The method could have many uses in plant anatomy and, as a teaching tool, help to interest students in the dynamics of plant anatomy.
Log in to add this item to your schedule
1 - Harvard University, Dept of O.E.B., 16 Divinity Avenue, Cambridge, MA, 02138, USA
2 - Harvard University, Harvard Forest, Po Box 68, Petersham, Massachusetts, 01366, USA
Presentation Type: Oral Paper:Papers for Sections
Date: Monday, July 28th, 2008
Time: 9:45 AM