Lab Notes and Procedures-09 Biology 1004
North Arkansas College
Topic: Plant Growth Regulators
- Auxin - Compounds related in structure to amino acid tryptophan. Cells treated with Auxin elongate.
- Cytokinins - A group of compounds related in structure to adenine. Cytokines stimulate cell division. Cytokinins are thought to be produced at the root tip, but other sources have also been identified.
- Gibberellins - Promotes seed germination as well as cell division and elongation. Plants lacking gibberellins, or plants that cannot respond to the gibberellin signal, are dwarfed.
- Ethylene - Ethylene, the only known plant growth regulator that is a gas, promotes fruit ripening and leaf abscission. Because it is a gas, ethylene produced by one plant can affect other plants surrounding it.
- Abscisic Acid - Inhibits seed germination and promotes the dormancy of plants during winter. Abscisic acid is sometimes referred to as the "stress hormone" because its levels rise in tissues that are subjected to stress, particularly water stress.
Lab Project
12 pots of wild type plants (A)
4 pots of Auxin resistant plants (B)
4 pots of dwarf #1 plants (C)
4 pots of dwarf #2 plants (D)
4 pots of Abscisic Acid resistant plants (E)
8 pots of ethylene over producer (F)
4 pots of grass plants (G)
- Prepare the above-mentioned pots. Fill pots with moist potting soil. Place 3-4 seeds on surface and press gently into the soil. Place pots in trays with water. Cover with Saran Wrap.
- Auxin and Tropism experiment. Prepare 60 mm plates of plant growth agar.
- Wild type seeds
- Auxin resistant seeds
- Wrap in Paraffin or Saran Wrap
- Abscisic Acid and seed dormancy experiment. Prepare 60 mm petri dishes with filter paper (dampen with water).
- Sow with wild type seeds
- Abscisic Acid resistant mutant
- Place 1 ml of Abscisic Acid solution onto filter paper using sterile pipette.
- Prepare 2 plates with medium; prepare 2 plates with filter paper.
