1. Unit 2 Plant Anatomy Horticulture
Roots
Unit 2 Plant Anatomy
Horticulture

2. What do roots do? absorb nutrients and moisture
Purpose of roots:
absorb nutrients and moisture
Anchor the plant in the soil
Provide physical support for the stem
Serve as food storage organ

3. Types of Root Systems
Tap Root
Fibrous Roots
Adventitious roots
others

4. Taproot consist of one primary root with few branches
fare well during droughts because their roots go deeper into the ground
Ex. Carrots, dandelions

5. Advantages and Disadvantages of Taproots
Penetrate deeper into the soil
Obtain water from lower levels
Anchor the plant
Disadvantages
Difficult to remove/harvest plants
Do not stabilize the soil well

6. Fibrous Roots
roots consisting of lateral roots near the surface of the soil
responds quicker to fluctuations in water and nutrient levels because they tend to be shallow

7. Advantages and Disadvantages of Fibrous Roots
Less drought resistant
Tend to get exposed during cultivation
Advantages
Shallower, thus respond more quickly to fertilization/irrigation
Stabilize the soil better

9. Adventitious Roots
roots that appear at locations other than the normal root system
develop from aerial portions of the stem
ex. Prop roots on corn plants

10. Adventitious roots

11. Root Anatomy

12. Terminology Meristem- Apex tissue that produces new cells
“Growth Tissue”
Apex
at the tip
Meristematic Apex – at the tip of the root where new cells grow

13. Anatomy of the Root Root cap Zone of Cell Division (Meristematic)
Root is divided into sections: (bottom up)
Root cap
Zone of Cell Division (Meristematic)
Zone of elongation
Zone of maturation/maturation

14. Root Cap Protects the cells of the root
Tough outer covering, pushes through the soil

15. Meristematic Zone/ Zone of cell division
located at the very tip of the root.
manufactures new cells through mitosis (replication)

16. Zone of Elongation
these cells increase in size and push the root through the soil

17. Zone of Maturation
cells undergo changes in order to become specific tissues such as:
the epidermis
cortex,
vascular tissue

18. Other parts of the root and functions.
Epidermis
the outermost layer of cells surrounding the root
responsible for the absorption of water and minerals that are dissolved in water.
root hairs develop here

19. Parts of the root Cortex Vascular tissue
cells involved in the movement of water from the epidermis to plant tissue and in food storage
Vascular tissue
conduct food and water
located in the center of the root in dicots and in bundles in monocots
Xylem and Phloem: tube like structures that carry nutrients to the rest of the plant

20. External Parts of the root
Root hairs
found along the main root
performs much of the actual water and mineral absorption.
produced in the zone of maturation