Leaf Arrangement
Phyllotaxis refers to the arrangement of plant leaves on a stem. The basic arrangements are alternate and opposite leaf positioning. Sometimes it can also be whorled if many leaves appear to rise from the same node. In the opposite arrangement, two leaves face opposite sides of the plant stem.
Alternate Phyllotaxy
Alternate phyllotaxy is the most common type of leaf arrangement. As per the name, the leaves are arranged in an alternate fashion. Here, only one leaf is present at a single node. This means each leaf will arise from a different node from the sides. Examples – Hibiscus, Sunflower, etc.
Whorled Phyllotaxy
This type of leaf arrangement is rarely seen in plants. Here, two or more leaves arise from a single node. It is usually seen in plants with short internodes. Sometimes they can be seen as basal leaf structures attached to a small basal shoot. This basal whorl can give a rosette-like appearance. Example – Macadamia, Barbejum stellatifolium
Difference between Alternate and Whorled Phyllotaxy
Alternate Phyllotaxy |
Whorled Phyllotaxy |
| It is a type where leaves are arranged in an alternate fashion. | Here, many leaves arise from the same point on a stem. |
| Only one leaf arises from a single node. | Two or more leaves arise from a single node. |
| It is the most common type of leaf arrangement in plants. | It is a fairly unusual arrangement of leaves. |
| Example – Hibiscus syricus, Helianthus, etc. | Example – Macadamia, Barbejum stellatifolium |
Also see: Morphology of Leaf
Frequently Asked Questions
What is a rosette?
It is the circular arrangement of the leaf or leaf-like structures in a plant. Rosettes are usually formed at the basal portion near the soil. Here, the internodes between the leaves are almost non-existent. Example – Ricciocarpos (liverwort).
What are internode and node?
A node is a point where the leaves attach to the stem. The interval between two nodes is called an internode. The internodal area is vital in deciding the plant height.
What is distichous phyllotaxis?
It is a ‘two-ranked’ arrangement of leaves on a stem. They can be in either alternate or opposite fashion. Here, the leaves are placed in two vertical ranks on opposite sides. It is seen in Gasteria, Clivia and Boophone plants.
The arrangement of leaves on the stem is called?
The arrangement of leaves on the stem is known as phyllotaxy.
Also Read: Parts of Plants
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