22nd Annual Student Research Conference
Determining the Correlation Between Age-related Changes in Gravitropism and Auxin Sensitivity in Flax (Linum usitatissimum) Roots with a Mathematical Image Analysis Algorithm
Yu-yu Ren* and Bo M. Forrester
Prof. Zhong Ma and Dr. Todd Palumbo, Faculty Mentors
Gravitropism, or gravity-induced spatial configuration, is essential for plant growth and development. We observed that both gravity response and sensitivity of flax seedling roots deteriorate readily after root emergence, and investigated whether this is correlated with changes in the sensitivity of root tissue to auxin. Roots of different ages were tested for their gravitropic response and sensitivity under a wide range of exogenous auxin concentrations. To quantify gravitropic curvature precisely and accurately, we developed a mathematical algorithm that minimizes the ambiguity intrinsic to the manual measurement. Combined with edge detection and image segmentation techniques, the algorithm smoothes the identified root medial axis and computes the mathematical curvature at each point along the axis. The gravitropic bend angle is then determined based on the curvature profile. Our analysis suggests that age-dependent decrease in gravity sensing and response is associated with reduced tissue sensitivity to auxin and/or changes in root gravisensing machinery.
Keywords: gravitropism, auxin, flax, image segmentation , medial axis , curvature
Topic(s):Biology
Presentation Type: Oral Paper
Session: 45-3
Location: VH 1328
Time: 1:45