Fusion detection in time-lapse microscopy images : application to lipid droplets coalescence in plant seeds

Detecting fusion events between lipid droplets of Arabidopsis thaliana embryos is of significant interest to understand the role of lipid droplet proteins. Lipid droplet proteins, called oleosins, have been shown to influence the size of lipid droplets possibly by preventing coalescence. We propose to detect fusion events in timelapse microscopy images of several oleosin deficient A. thaliana embryos. To detect volume preserving fusion events in a dense environment, we propose a procedure based on particle tracking and statistical tests. Using synthetic data, we compare the performances of our method to heuristic decision rules adapted from tracking algorithms from the literature.