Return to
K-12
Plant Path-Ways
Menu Page

If you would like to contribute to this section, see Instructions for Authors.

Education Center | K-12 Plant Path-Ways to Science

K-12 Teacher's Guide
to Lessons and Laboratories

Water Molds by Gail L. Schumann and Claudia A. Jasalavich
An introduction to an important group of soil and water organisms (the Oomycetes) and an opportunity to conduct some simple biodiversity exercises. This exercise could be used for all K-12 age groups and learning levels, but will be most useful for grades 7-12 in classrooms where dissecting and compound microscopes are available. It requires minimal materials (jars, popcorn, and natural water sample) and preparation.

Crime Scene Investigation (CSI) with Powdery Mildew Fungi by Gail Ruhl
This exercise can be used to stimulate the investigative nature of your students as they use forensic plant pathology techniques with powdery mildew cleistothecia (the sexual stage of powdery mildew fungi) to prove their innocence in a mock murder investigation. The exercise is suitable for grades 7 -12 and does not require the purchase or maintenance of special cultures, since cleistothecia produced by powdery mildew fungi are easy to find on plants in nature. Dissecting and compound microscopes are required.

DNA the Easy Way (and "Gram Stain" Without the Mess) by Gail L. Schumann and Claudia A. Jasalavich. This demonstration can be used to help students visualize DNA by lysing (breaking open) bacterial cells on a slide and “stringing up” the DNA with a toothpick in less than one minute. It is most useful for grades 7-12. It requires minimal materials (bacterial cultures, glass microscope slides, 3% (w/v) potassium hydroxide (KOH), and wooden toothpicks). This technique can also be used to study bacteria because only Gram-negative bacteria lyse in 3% KOH; Gram-positive bacteria do not. The technique is equivalent to the Gram-stain reaction, but does not require a microscope or potentially messy stains.

Nematodes: Plant-Parasitic Worms by Greg Tylka and Claudia A. Jasalavich. An introduction to the world of nematodes. This exercise will be most useful for grades 7-12 in classrooms where dissecting and compound microscopes are available. It requires minimal materials (funnels, screen, tubing, clamps, 2-ply tissues, ring stand, soil sample, and water) and preparation.

Who Done It? Or what's that brown fuzzy stuff on my plum? by Claudia A. Jasalavich and  Gail L. Schumann. A safe and simple exercise that uses Koch's postulates to prove that an observed fungus is the cause of  fruit disease. This lesson is suitable for grades 7-12 and does not require the purchase or maintenance of special cultures. Since the fungus that causes brown rot of stone fruit (e.g. apricots, peaches, nectarines, plums, cherries) is present naturally on the surface of these fruit, stone fruit purchased from the supermarket or farm stand will usually develop the disease. The fungi responsible for brown rot of stone fruit are not human pathogens. This lab requires dissecting and compound microscopes. A simplified exercise, without cultures, to demonstrate the Germ Theory also is described.

Plant Parts and Their Diseases by Wade H. Elmer and James A. LaMondia. This exercise is designed for young children (K to 3) to teach the different parts of a plant (root, stems, leaves, flowers, fruit, and seeds), the basic functions of each part, and to show that tiny microscopic organisms (“germs”) can cause each part of a plant to become diseased. The lesson shows children the importance of understanding what causes plants to be sick and the need for scientists called plant pathologists to keep plants healthy. It requires easily available materials and minimal preparation time.

Powdery Mildew Fungi: Classification and Ecology by Gail E. Ruhl and Claudia A. Jasalavich. An introduction to a common group of fungi, the powdery mildew fungi, which are obligate parasites of plants. This exercise can be used to explore the ecology of a diverse group of fungi and/or as a way for students to learn about how fungi are classified. This lesson does not require the purchase or maintenance of special cultures, since powdery mildew fungi are easy to find on plants in nature. Teachers and/or students collect leaves infected with powdery mildew fungi from different kinds of plants and examine them with dissecting and compound microscopes.

Antigen-Antibody Testing: A Visual Simulation or Virtual Reality by Daniel Schadler. When a virus encounters an antibody that reacts with antigenic proteins in the viral particle, the virus and antibody clump together. When carried out under appropriate conditions, this clumping reaction will produce a visible product. Using real viruses and real antibodies to demonstrate this phenomenon is prohibitively expensive for most K-12 teachers. Less costly inorganic salts can be used to simulate the reaction. This demonstration is appropriate for life science courses that introduce the concepts of viruses, antigens and antibodies; it is also appropriate as a general demonstration of diffusion.

Tobacco mosaic virus (TMV) by Rosemary Ford and Tom Evans. TMV provides an excellent model for teaching students about properties of a plant virus and the relationship between a virus and its host plant. This virus is quite stable and transmits easily, thus students can use it quite successfully in the laboratory. Four activities geared toward grades 9-12 are described.

Classroom Activities in Plant Biotechnology by Janice Stephens. Activities to introduce elementary and high school students to the basics of plant biotechnology. It includes several classroom experiments that can be modified to suit the ages of the students. Some units require students to research and write their own opinions on the use, risks, and benefits of plant biotechnology in today's world as well as the impact of changing climate on food production regions of the world.

1. DNA extraction
2. Gel electrophoresis of dyes
3. Restriction enzyme analysis - methylene blue stain
4. Transformation of E. coli using green fluorescent protein
5. Plant tissue culture in the classroom
6. Polymerase chain reaction
7. Effect of environment on plant growth
8. Research suggestion