How to Identify the Parts of a Wheat Plant

This is a mature wheat field.

Wheat is a grass, and as such has the same basic structures other grasses. Wheat is more than just roots, leaves, and grain. It has various other structures that become apparent as it develops from a seed into a mature plant. Identification of these structures is important to botanists. It is also important to farmers and field men. They need to know what stage the wheat is in prior to spraying herbicides. The plant structures help the farmers know what developmental stage the wheat is in.

Things You'll Need

• Mature wheat plant
• Bucket
• Water
• Forceps
• Sharp knife
• White cardboard
• Pins
• Jeweler's loop

Instructions

Dissection of the Wheat Plant

1. Remove the wheat plant from the pot or soil media it has been growing in. Pour a gallon of water in the bucket. Thoroughly wash the roots in the bucket of water. Pin the wheat plant onto the white cardboard.

2. Remove roots by cutting then off at the crown of the plant. The crown is the part of the plant were the roots and the stem meet. The root system is composed of many small rootlets that branch out in many directions. This is called a fibrous root system.

3. Dissect the leaf and stem. With the forceps holding the tip of the leaf, pull leaf away from the stem. The leaf is wrapped around the stem beginning at the leaf collar down to the node. The node is the small swelling at the terminal end of the leaf. The area between the nodes are called inter nodes.

4. Cut the leaf collar away from the rest of the leaf. Inspect the collar area with the loop or a magnifying class. There will be two small arms of tissue that stick out from the collar. These are the auricles of the leaf, and when intact they wrap around the plant stem. The auricles are hairy in the wheat plant. Inspect the inside of the leaf surface at the collar. You will be able to cut away a small papery structure that stands up from the collar. This is the ligule.

5. Dissect the seed head, which is composed of many individual seeds. With your fingers remove one seed. The seeds are covers with a small bit of chaff on each side. These structures are called the lemma and the palea. Each seed is protected by these structures. Barley also has a lemma and a palea on each seed, but these structures are fused to the seed itself and are not easily removed.

Tips & Warnings

• When the wheat plant reaches the four leaf stage it will usually produce a second stem. This second stem is called a tiller. If the conditions are right and there is enough sun and fertility, this tiller will produce a second seed head on the wheat plant.

• Be careful when using the knife to cut the various plant parts. It is recommended that your use gloves when using the knife to protect your hands.

References

• "Growth Staging of Wheat;" James Nelson; 1988
• "Principles of Field Crop Production;" John Martin; 2006

Resources

• "Botany of the Wheat Plant;" E. Kirby