2018 ASHS Annual Conference

Allelopathy plays crucial roles in invasive plant viability and agricultural production systems. However, there is no well-established hands-on learning activity to teach the concept of allelopathy. Nor is there an activity which allows students to gain knowledge about glucosinolates and their corresponding enzyme, myrosinase, which are present in almost all brassica crops. This study explores an inexpensive and easy allelopathy laboratory activity for undergraduate students majoring in chemistry, biology, agronomy, and/or horticulture. Students were split into groups throughout the experiment. Lettuce germination was counted from three different treatments including water-treated with Parafilm sealing, horseradish-treated with Parafilm sealing, and horseradish-treated without Parafilm sealing 22 hours after seed sowing by the students. Additionally, lettuce root length was measured by students using ImageJ software from each treatment using pictures captured by students’ smartphones. Students took an identical quiz as a pre-lab and a post-lab assignment. Their average scores on the pre and post-lab quizzes were 3.2 and 6.5 out of 10, respectively, indicating the lab activity improved students’ understanding of allelopathy and glucosinolate-myrosinase system. In addition, students (n=76) completed a survey post-lab to assess their self-efficacy. A vast majority of students agreed “I can utilize a smartphone to collect data for plant science experiment” (88%), “The lab activity improves my knowledge on weed suppression mechanism of brassica cover crops”(83%), and “The experiment was designed to improve my knowledge on allelopathy” (84%). This simple and cost-effective lab activity was very helpful as it made learning more inviting, meaningful, and fun.