Root Scans to Document Fertilizer Response

A growth chamber rhizotron project was designed to demonstrate the influence of plant nutrients on root growth using time-lapse videos. A secondary goal was to develop a teaching tool that could be shared with other educational institutions for classroom demonstration of root development. The rhizotron project continues to be a laboratory experience for a crop physiology class and is currently in its 7th semester (approx. 100 students have been involved). In between semesters, the rhizotrons have been used to conduct undergraduate research projects. In 2013, two student projects were conducted: 1) manure placement on seed emergence and root growth and 2) the effect of various fertilizers and their placement on wheat germination.

The rhizotron project has been a valuable teaching, learning, and research tool for the students. As part of the crop physiology class, students design their own research project using the rhizotrons. Student projects have included a wide variety of crops (alfalfa, wheat, barley, corn, soybeans, and potatoes) and fertilizer treatments (rates, placements, N and P combinations and compost). The rhizotron has been a motivating teaching tool and has facilitated student understanding of root growth and fertilizer response.

In 2013, we began collaboration with the university communication service to create time-lapse videos of root growth. The videographer students are assisting agronomy students in setting up the rhizotrons. Fertilizer treatments consisted of type, amount and placement of fertilizer. Each rhizotron was programmed to take a root scan every 15 minutes for 10 days. The scans were used to create time-lapse videos that have been posted to YouTube. The videos are used in classrooms to demonstrate root response to fertilizer.