Renata Belisário, Jacob Ball, Laura Tew, and Lisa Vaillancourt. 2021. A Short Course In Plant Pathology For Middle School Through Remote Learning . The Plant Health Instructor. DOI: 10.1094/PHI-E-2021-0426-01
Module 1: Plant Disease Detective
To introduce and define basic concepts in plant pathology including:
the importance of plants
the existence of plant diseases
the four main groups of pathogens (fungi, bacteria, nematodes, and viruses)
common plant disease symptoms.
To help students recognize plant diseases in their environment.
To demonstrate the scientific method for plant disease identification.
Materials and Resources Needed for Each Student
A smartphone or a tablet with a camera, and a computer with internet access, a microphone, and a web camera.
Phone apps for plant identification such as PlantNet, PlantSnap, or PictureThis.
Hand lens or a free magnification phone app such as Magnifying Glass + Flashlight.
Access to Canvas, Zoom, Google Docs, and Google Slides.
Digital or printed copy of Williams and Boehm, “Plants Get Sick Too" 2017.
Zipper seal bag containing a paper towel.
Order of Activities
Figure 1. Packet of learning materials delivered to students prior to the course.
Figure 2. Flowchart of the short course with the timeline and organization of the modules.
Prior to the start of the module: About two weeks before the class began, we sent a packet of learning materials to each student by mail (Fig. 1). These included a flow chart with the course timeline (Fig. 2), a hand lens, a highlighter, a zipper seal bag containing a paper towel, and a printed copy of the assigned reading for Module 1 (Williams and Boehm, 2017). We did this for two reasons. The first was to create a sense of excitement and anticipation in the students for the course, and allow students to read ahead if they chose. The second reason was to ensure that all the students had access to the same physical resources for the virtual course.
First synchronous class session: During the first synchronous Zoom class meeting, the instructors began by introducing the students to the Canvas course site and ensuring that they understood how to access it and navigate through it. Students were given an opportunity to ask questions. Then it was time for the first in-class activity, an ungraded quiz with three open-response questions. The questions were:
1. In your own words, what is a plant disease?
2. In your own words, what do sick plants look like?
3. In your own words, why do we need to care about plant health?
The purpose of this pre-quiz was two-fold: first, to promote student interest and curiosity about the material they would be learning, and second, for the instructor to assess the level of pre-existing knowledge (definition of the term plant disease), comprehension (explanation of the importance of plant health), and analysis (identification of patterns associated with diseased plants) among the students, in alignment with the levels of Bloom's Taxonomy of Learning Objectives (1956).
Figure 3. Bitmoji classroom embedded in Canvas for Module 1: Plant Disease Detective.
After the students had been given ten minutes to do the quiz, the instructors provided an opportunity for them to share their answers with their peers, and then the class moved on together to the Module 1, Part 1 introductory page on Canvas. The instructors highlighted the information on this page related to the structure and objectives of the course and of the module. The instructors then showed the class how to enter the Bitmoji classroom (Fig. 3), played the recorded welcome message, reviewed the tasks on the Bitmoji classroom blackboard, and activated the linked video (https://rb.gy/rwfo4n). The pre-recorded introductory video was designed to be accessible and relevant for middle-school youth with no background in plant pathology. About 6.5 minutes into the video, it was paused at the prompt so that students could read the assigned article published by the Ohio State University (Williams and Boehm, 2017). They were encouraged to read actively by using their highlighter to identify the answers to three questions:
Why is it important for us to study plant diseases?
What is a plant disease and how is it different from a plant injury?
What are the seven general categories of symptoms that indicate that the plant is sick?
Students were given about 20 minutes to scan the article and highlight the answers. Once the students returned to the group, they discussed their answers to these questions with the instructor's guidance and tried to develop a consensus. Then they returned to the video in which the questions were addressed, supported with references to the assigned reading. This process of revisiting the questions was designed to help the students to understand and retain the key concepts necessary for the following modules and assignments in accordance with NIET (2020).
The remainder of the first synchronous class session was spent with the instructors introducing the first homework assignment. The Module 1 homework assignment is an independent activity in which students are instructed to go outside, find a sick tree, make observations, and collect and preserve a symptomatic leaf. The goals of the assignment are to encourage students to use their powers of observation and the scientific method to recognize sick plants in their environment, and to apply terminology associated with plant disease symptoms by reporting their observations. To introduce the assignment, some typical disease symptoms were described and illustrated on the Canvas homework assignment page. Step-by-step instructions were provided, both as text and visually as a flow chart. An exemplar video was produced that uses a pawpaw leaf spot to show how to identify trees with disease symptoms, how to observe symptomatic leaves with a hand lens, and how to collect and preserve healthy and diseased leaf samples. A second video explained the purpose of a moist chamber, and how to make one from a plastic zipper seal bag).
After collecting leaf samples, taking photographs, and filling out a questionnaire based on their observations (Appendix 1), students were required to create and submit a photo report describing their findings via Google slides. An exemplar that used the pawpaw leaf spot example was provided for this assignment. They were also required to upload their answers to the questionnaire (Appendix 1) via Google docs. This questionnaire was designed to guide their observations and assist with the process of diagnosis.
Second Synchronous Session: During the second synchronous class session, the class logged in to Module 1, part 2 and the instructor checked in with the students on the progress of their homework assignments, invited students to share their experiences and observations related to the assignment with their peers, and answered any questions. Some discussion questions were provided to help students share their observations. The instructors went back over parts of the assignment page and the exemplars to help students more fully understand the requirements of the homework assignment and emphasized the deadline for the assignment.
At the end of the second synchronous session, students took a graded quiz consisting of the same three questions that they had answered prior to the start of the course. This measured gains in knowledge, helped the instructor evaluate achievement of instructional objectives, and assessed students' learning process during the first module.
Graded assessments for the first module included the final quiz, the photo report and the completed assignment questionnaire (these last two were assigned only “S" or “U" grades, based on whether they were completed on time).
Providing instructions in multiple formats, including verbal, written, and as exemplars, was very helpful in ensuring that most students were able to complete the assignment successfully. Because this was a fairly complex multipart assignment, instructors may find it useful to include more checkpoints prior to the assignment deadline in which students are asked to submit individual components, e.g. photographs or notes, as early drafts. This may be particularly important if the course is more asynchronous, with fewer opportunities for the instructor to check in directly.
A few students included images from the internet in their photo report. We recommend emphasizing the importance and purpose of using original images and requiring the pictures to include the students' hands holding the diseased leaf, or placement of a unique item alongside the specimen, e.g. a sticker or other token that could be mailed in the kit to each student.
A few students uploaded photos of abiotic disorders, or of damage caused by insects. This was expected as part of the learning process. The differences between abiotic disorders and biotic diseases were discussed during the meetings with plant pathologists in Module 2.
Module 2: Meet a Plant Pathologist
- To teach students how to recognize and access reliable information about plant diseases.
- To apply the scientific process (observation, prediction, critical thinking, and communication) to diagnose the sick plant identified in Module 1.
- To learn more about plant pathology as a career.
Materials and Resources Needed for Each Student
- Computer with internet access, a microphone, and a web camera.
- Internet search engine to find resources related to plant disease diagnosis.
- Access to Canvas, Zoom, Google Docs, Google Slides or PowerPoint, and Screencastify.
- Samples, notes, questionnaire, and photo report from Module 1.
Order of Activities
Prior to the start of the module: In the second module of the short course, students were given an opportunity to consult individually with a plant pathologist about the sick plant they had identified in the first module. We recruited a team of graduate student and faculty volunteers from our department for this activity before the class began. Each had to undergo a background check before being cleared by the school to work with the students. Each volunteer was assigned to three or four students. Volunteers received training to explain the goals and format of the module activity. They were instructed to begin the consultation by asking students what they would like to learn, and they were given a prepared list of questions for the students to help keep them engaged in conversation. The volunteers were asked to assist the students in applying the scientific method of disease diagnosis by considering the evidence that their plant was sick versus healthy. They were to assist them to identify reliable and relevant internet resources, e.g. from university extension departments or government articles. Volunteers were also asked to tell the students about their work as professional plant pathologists and answer any questions that the students had about plant pathology as a career. Just before the second module began, we gave the volunteers access to their students' assignments from Module 1 so that they could be prepared to demonstrate how to find reliable information on the internet and diagnose the sick plants.
Figure 4. Bitmoji Classroom embedded in Canvas for Module 2: Meet a Plant Pathologist.
First Synchronous Class Session: During the first synchronous Zoom session, the class accessed Module 2, Part 1 on Canvas together and the instructors summarized the introductory information including the objectives of the Meet a Plant Pathologist activity. The class then entered the Bitmoji classroom (Fig. 4), and the instructor activated a video exemplar that was designed to help the students plan for their meetings with the plant pathologists. After presenting information about plant pathologists and what they do, the video continued with a dramatization of a meeting between a student and a plant pathology volunteer, with a student intern playing the part of the plant pathologist and one of the instructors in the role of the student. The goal of this video was to prepare the students for a professional interaction with the plant pathologist, modeling the expectations for communication of their observations and career questions. After the video, students had the opportunity to ask questions, and the instructors provided additional guidance.
For the remainder of the class time, the instructors used the Canvas assignment page to introduce the homework for Module 2. The assignment was to produce a three- to five-minute video report to communicate the students' plant disease observations and diagnosis results to their peers and instructors. The goals of this assignment for the students included: 1. Learn how to access reliable expert information to differentiate a healthy plant from a sick one; 2. learn that a pathogen can affect plants in different ways; 3. apply the scientific process to disease diagnosis (observation, prediction, critical thinking, and communication); and 4. practice communication skills by producing an organized and creative video to explain their findings. The students used the Chrome extension Screencastify to produce the video reports, using their photo report as a starting point. A check list of success criteria for the video were provided on Canvas (Appendix 2), along with the instructions for the activity. An exemplar was provided that addressed all the rubric requirements (https://youtu.be/VUq8G1RPI4k). Students were encouraged to summarize essential points while also being creative and mixing text with photos and drawings.
Second Synchronous Class Session: During the second synchronous class session, the class logged in to Module 2, part 2, and the instructors reviewed some guidelines for the students that would help their zoom meetings be more successful. These guidelines included:
Check your audio and camera before the meeting begins
Please be on time and be sure you have everything for the virtual meeting
The plant pathologist who will meet with you will have seen your photo report from Module 1. However, they may still have questions for you about your sick plant
Therefore have all your observation notes in your notebook ready before the meeting starts, and be sure you are ready to answer questions
Take notes during the meeting so that you can remember everything for when you do your final report
Ask as many questions as you want about the sick plant that you collected
You may also want to ask the plant pathologist about their career. The instructors also made some suggestions about some questions to ask the plant pathologists. Examples were provided including:
Where do plant pathologists work?
What do I need to do to become a plant pathologist?
Who do plant pathologists collaborate with?
What are you investigating?
What is fun about being a plant pathologist?
For the remainder of the second synchronous session, the volunteer plant pathologists met individually with their students in Zoom breakout rooms. Each meeting was 15 minutes long. While some students were in the breakout rooms, the instructors used the time to answer any questions from the remaining students about the homework assignment. As students came out of the breakout rooms, the instructors asked them to share some of their impressions and experiences from their meetings with the rest of the group.
A rubric was designed for assessment of the students' video assignments in alignment with Clay (2001) (Appendix 3). The rubric is aligned with the learning outcomes, thereby assessing knowledge assimilation, clear communication, application of plant pathology concepts, and the ability to follow the scientific method. A rating of between one and five was assigned for each criterion, considering qualities of both the video and the presentation. Students received the rubric before submitting their final assignments so they would be aware of how they would be evaluated and prepare accordingly. To encourage students to think critically about their own learning process, we also developed a self-assessment that was assigned along with the video report. Students rated their responses to each of five statements with a number between one (strongly disagree) and four (strongly agree).
Statement 1: I described my scientific observations related to my plant disease very thoroughly, and I included enough detail so that I was able to make a conclusion about the cause of my plant disease.
Statement 2: I understand how to identify and use reliable resources to diagnose plant diseases.
Statement 3: I took notes during my talk with the plant pathologist, and the notes were helpful when I prepared my final video report.
Statement 4: I carefully followed all the steps in developing and testing my hypothesis (observations, description of the sick plant, background research using reliable sources, consulting an expert).
Statement 5: I took advantage of the opportunity to ask the Plant Pathologist questions, and I learned new things about plant disease diagnosis and about Plant Pathology as a career.
A few students were unable to attend their scheduled meeting time. Instructors should ensure that they have at least one volunteer with flexibility to meet those students by Zoom at a different time outside of class.
Several students had difficulties with Screencastify. Besides the project exemplar, it may be useful to produce another video to explain the use of this tool in more detail. The instructor may need to meet with individual students one-to-one to demonstrate and assist. Alternatively, another technology might be more suitable for this assignment.
A few students had not completed their assignment from Module 1 in time for their meeting with the plant pathology volunteers. We found it was useful to have a sample project for the volunteers to use in their meetings with these students. An exemplar describing a red maple with symptoms of purple-bordered leaf spot caused by Phyllosticta sp. was used for this purpose (https://bit.ly/3ugGqSQ).
Because the assignment is quite complex, the instructor may find it useful to include additional checkpoints or guided practice sessions for students to allow incremental improvements in their video reports prior to the submission deadline.
Module 3: Let's Share What We learned
To introduce the concept of peer review as it is applied to scientific research.
To demonstrate that a rigorous peer-review process is used to evaluate originality, quality, and validity of the research.
To teach students how to provide and receive constructive criticism.
To provide a summary overview of the information presented during the short course.
Materials and Resources Needed for Each Student
Computer with internet access.
Access to Canvas, Zoom, Google Docs, Google Slides or PowerPoint, and Screencastify.
Rubric from Module 2 (Appendix 3).
Order of Activities
Prior to the start of the module: In this final module, students learned about the value of peer review in research and had the opportunity to peer review a video project that had been produced by one of their classmates for Module 2. The peer reviews were anonymous; only the instructor knew which student peer reviewed each of the videos. Prior to the start of Module 3, the instructor should assign the students for peer review to ensure that each video receives a review.
Figure 5. Bitmoji Classroom embedded in Canvas for Module 3: Let's Share What We Learned.
First synchronous class session: During the first synchronous Zoom class session, the instructors once again accessed the Canvas course site, and provided a summary and overview of the introductory information for Module 3. Then the class entered the Bitmoji classroom (Fig. 5) and activated a short video that provided a summary of the information that had been presented in the short course. Students were given the opportunity to ask questions and instructors used guided inquiry to encourage the students to think about and discuss the information together. During the second part of the session, the instructors checked in on the status of the video report homework assignments from Module 2. They answered any questions about the assignment or about the technology and ensured that the students were on track to complete their video reports on time.
Second synchronous class session: During the second and final synchronous class session, students were assigned to peer review one of their classmates' video projects using the same rubric as the instructor was using (Appendix 3). The goal of this peer-review session was to help the students see how constructive feedback can help them to improve their project outcomes. The instructor began by using the assignment page on Canvas to introduce the assignment and explain the objectives and procedure. Students were reminded that their role as a peer reviewer was to help their classmate to improve their work. They were cautioned that they should not be unkind, or use any unnecessarily negative language, and that they should be encouraging and try to point out strengths as well as weaknesses. Students were then given access to their assigned video and completed and uploaded their peer review, using the rubric to guide them.
At the end of the session, students were directed to a final assessment in which they were asked to answer five short essay questions related to the information that had been presented in the short course (Appendix 4).
The peer review was evaluated based on whether the student had provided thoughtful, constructive comments. To avoid reductive feedback on students' work by quantitative grading, the rubric also contained free-comment spaces that allowed communication of strengths and areas for improvement in accordance with Antonova (2019). Anonymous peer comments and reviews were included, as appropriate, in feedback that was provided to each student on their video reports by the instructors.
A few students had not turned in their video reports by the deadline. To account for this, it was necessary for the instructor to adjust the peer-review assignments, and some projects had more than one peer reviewer.
If the timeline of the modules was adjusted, the instructor could allow students to improve their projects after incorporating suggestions given by their classmates, so that they could practice the habit of using constructive criticism.