Estimating the plant stem emerging points (PSEPs) of sugar beets at early growth stages

Successful intra-row mechanical weed control of sugar beet (beta vulgaris) in early growth stages requires precise knowledge about location of crop plants. A computer vision system for locating plant stem emerging point (PSEP) of sugar beet in early growth stages was developed and tested. The system is based on detection of individual leaves; each leaf location is then described by centre of mass and petiole location. After leaf detection were the true PSEP locations annotated manually and a multivariate normal distribution model of the PSEP relative to the located leaf was built. From testing the system, PSEP estimates based on a single leaf have an average error of ∼3 mm. When several leaves are detected the average error decreases to less than 2 mm.