TubAR: A Simple, Open Source Program to Evaluate Tuber Quality Traits
Tuesday, July 27, 2021
12:00 PM - 12:15 PM
Measurements of potato tuber shape and skin traits often rely on subjective visual measurements. These measurements introduce opportunity for error due to factors such as lighting, time of day, and rater experience. It also makes ratings performed by different individuals or breeding programs difficult to compare. Check clones have been utilized to “calibrate” these visual measurements, however this does not account for genotype by environment differences that may lead to inaccurate calibration. A way to objectively evaluate tubers would therefore be advantageous to breeders. An image analysis approach, using a lightbox and camera, could provide this objectivity in a simple and low-cost manner. TubAR (Tuber Analysis in R) is a package in the R programming language which provides a means of obtaining measurements of several tuber traits. The package currently measures shape traits including tuber length, width, and roundness. The package also measures skinning percentage, redness, and lightness. Use of TubAR for phenotypic evaluation in a breeding program across years and field sites is expected to raise potential genetic gain at a relatively low cost. In the University of Minnesota breeding program, broad sense heritability for skinning was raised from 0.62 to 0.68, and from 0.58 to 0.63 for skin color. It can also provide a better measure of genotype by environment effects in situations such as national trials. In the near future, it is anticipated that TubAR will also be able to evaluate diseases and storage disorders including pressure bruise, common scab, and silver scurf.