Plant Anatomy Roots Part 2

Topics Taproot system Taproot system Xylem/ Phloem Xylem/ Phloem Healthy Roots Healthy Roots Root Tuber Root Tuber Fibrous root system Fibrous root system Understand what healthy roots look like Understand what healthy roots look like Identify the internal layers of a root Identify the internal layers of a root Know the different types of root systems Know the different types of root systems Objectives

A. Cortex – this is where the root stores the food produced by the leaves A. Cortex – this is where the root stores the food produced by the leaves B. Endodermis –controls the movement of water and minerals into the xylem and phloem B. Endodermis –controls the movement of water and minerals into the xylem and phloem C. Pericycle – a layer found inside the endodermis which may produce lateral roots C. Pericycle – a layer found inside the endodermis which may produce lateral roots Layers of Cells in the Root

D. Vascular cylinder – forms the central cylinder of the root; it is made out of two secondary transport tissues D. Vascular cylinder – forms the central cylinder of the root; it is made out of two secondary transport tissues 1. Xylem – carries the water taken in by the root up the plant to the stems and leaves 1. Xylem – carries the water taken in by the root up the plant to the stems and leaves 2. Phloem – carries the food produced by the leaves down to the roots to be stored 2. Phloem – carries the food produced by the leaves down to the roots to be stored

Internal Layers of the Root Lateral Root Xylem Phloem Pericycle Endodermis Cortex Root Hairs Vascular Cylinder

What Are the Two Types of Root Systems? Plant root systems are organized in two basic ways Plant root systems are organized in two basic ways Taproot Taproot One main root One main root Ex. Carrot Ex. Carrot Their roots reach far into the ground; they can be several feet long. Their roots reach far into the ground; they can be several feet long.

Examples of Taproots CarrotBeetSweet potato

Root Tubers Another form of root that produce a large food storage root Another form of root that produce a large food storage root Sweet Potato Sweet Potato Used in propagation. Used in propagation.

Fibrous Root Fibrous Root No primary root-made of many roots of similar size No primary root-made of many roots of similar size EX: Grasses, EX: Grasses, They usually never grow below the first 6-12 inches of soil They usually never grow below the first 6-12 inches of soil Fibrous root system of grass

What Does a Healthy Root System Look Like? A healthy root system is white or nearly white in color and smells fresh, or earthy A healthy root system is white or nearly white in color and smells fresh, or earthy If roots are black, brown, or dark orange and smell rotten or sour, the root system is having some problems If roots are black, brown, or dark orange and smell rotten or sour, the root system is having some problems

Proper Watering Proper Watering If in pots, be sure that there are drainage holes in the bottom for extra water to drain If in pots, be sure that there are drainage holes in the bottom for extra water to drain Water plant till soil is saturated and water drips out of the drainage holes Water plant till soil is saturated and water drips out of the drainage holes This encourages the roots to grow through the entire pot This encourages the roots to grow through the entire pot Allow the pot to dry out slightly between watering Allow the pot to dry out slightly between watering Too much water is a common cause of root death Too much water is a common cause of root death Keeping a Healthy root