2020 Volume 102 Issue 4 Pages 254-262
To obtain the precise geographic coordinates and genetic line information of seedlings planted in the genetic test site for tree breeding, we developed a simple mapping method using an RKT-GNSS kit, C94-M8P application board, and individual seedling labels with a QR code. In the two test sites, we estimated the geographic coordinates of ca. 90 seedlings three times using a C94-M8P GNSS kit with post-processing kinematics analysis and real-time kinematic GNSS. The average standard deviations of replications were 2.6-6.0 cm for horizontal coordinates and 3.6-12.5 cm for vertical coordinates, indicating a high precision of measurements. To evaluate the accuracy of the method, we compared the geographic coordinates estimated using the C94-M8P and geographic coordinates measured as a true value using a dual-frequency GNSS receiver and a Total Station at one test site. The differences of the coordinates were 6.4 cm and 11.3 cm in horizontal and vertical coordinates, respectively. This suggests that the geographic coordinates estimated by the C94-M8P are very accurate. When we obtained individual identification codes of 90 seedlings from their QR code label using QR code reader and simultaneously obtained the geographical coordinates using the C94-M8P, the time required to obtain a measurement was 13-21 seconds per seedling. These results suggest that the new method is efficient and can be applied to real operations in forest tree breeding.
