American Journal of Potato Research

, Volume 94, Issue 1, pp 88–93 | Cite as

Potato Tuber Length-Width Ratio Assessment Using Image Analysis

  • Yongsheng Si
  • Sindhuja SankaranEmail author
  • N. Richard Knowles
  • Mark J. Pavek
Short Communication


Potato tuber length to width (L/W) ratio is a critical crop trait evaluated during the development and selection of new cultivars to assess the effects of environment and management on tuber size and shape. The major challenges in manual measurement of L/W ratio are that it is labor-intensive, time consuming, and sometimes inconsistent. A high-throughput, digital image-based method for estimation of L/W ratio was developed in this study. Tests were conducted using tubers from a local retail market (red, white and russet) and from a field experiment with Payette Russet cultivar specifically designed to alter tuber size and shape. An image processing algorithm was developed to process the potato tuber images and the L/W ratio data from the images were compared to manual caliper measurements. A high accuracy in tuber L/W ratio estimation was consistently observed using image-based analysis. Among the different potato cultivars, red cultivars had a lower average accuracy in L/W ratio estimation of 94%, while other cultivars exhibited 96% and higher average accuracies.


Machine vision Image processing Size analysis Phenotyping 


La relación largo-ancho del tubérculo de la papa (L/W, por sus siglas en inglés), es un carácter crítico del cultivo que se evalúa durante el desarrollo y selección de nuevas variedades para analizar los efectos del ambiente y de manejo en el tamaño y forma del tubérculo. Los mayores retos en las mediciones manuales de la relación L/W son la mano de obra intensiva que se requiere, el tiempo que les lleva, y algunas veces las inconsistencias. En este estudio, se desarrolló un método integral, basado en imagen digital para la estimación de la relación L/W. Se condujeron pruebas usando tubérculos de un mercado de menudeo local (roja, blanca y tipo russet) y de un experimento de campo con la variedad Payette Russet diseñado específicamente para alterar el tamaño y la forma del tubérculo. Se desarrolló un algoritmo de procesamiento de imagen del tubérculo de papa, y los datos de la relación L/W de las imágenes se compararon con mediciones manuales de un calibrador (tipo vernier, nota del traductor). Mediante el uso de análisis basado en imágenes, se observó consistentemente una alta precisión en la estimación de la relación L/W del tubérculo. Entre las diferentes variedades de papa, las rojas tuvieron un promedio más bajo de precisión en la estimación de la relación L/W de 94%, mientras que otras variedades exhibieron promedio de precisiones de 96% y mayores.



The research was performed at Washington State University. This research was funded, in part, by the USDA National Institute of Food and Agriculture, Hatch Project, 1002864 (WNP00821) and by the program of study abroad for young teachers sponsored by the Agricultural University of Hebei.


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Copyright information

© The Potato Association of America 2016

Authors and Affiliations

  • Yongsheng Si
    • 1
    • 2
  • Sindhuja Sankaran
    • 2
    Email author
  • N. Richard Knowles
    • 3
  • Mark J. Pavek
    • 3
  1. 1.College of Information Science and TechnologyAgriculture University of HeBeiBaodingChina
  2. 2.Department of Biological Systems EngineeringWashington State UniversityPullmanUSA
  3. 3.Department of HorticultureWashington State UniversityPullmanUSA

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