Abstract
To develop and test a system for computer-assisted image analysis, repeated video recordings of reed canary-grass roots (Phalaris arundinacea L.) were made in an 18-window rhizotron. The images were digitized and processed using a Unix computer and the Khoros software development environment.
Two image sizes, 126×95 mm and 61×46 mm, both comprising 650 × 490 pixels, were compared. Among image processing techniques used were median filtering, segmentation and skeletonization. Root area and length in both the topsoil and subsoil were estimated using the two image sizes. The resolution (image size) strongly affected the calculated root lengths. The results were compared with root length measurements obtained manually.
Statistically significant differences in root length and area in the topsoil were detected between the sampling dates using the computer-assisted methods. Possible sources of error and methods for reducing them are discussed.
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References
Andrén O, Hansson A-C and Végh K 1993 Barley root growth and nutrient uptake from two soil types in a rhizotron with vertical and horizontal minirhizotrons. Swed. J. Agric. Res. 23, 115–126.
Böhm W 1979 Methods of Studying Root Systems. Springer-Verlag, Berlin, Germany.
Cheng W, Coleman D C and Box J E 1990 Root dynamics, production and distribution in agroecosystems on the Georgia piedmont using minirhizotrons. J. Appl. Ecol. 27, 592–604.
Dorst L and Smeulders A W M 1987 Length estimates for digitized contours. Computer Vision, Graphics Image Processing 40, 311–333.
Gonzalez R C and Wintz P 1987 Digital Image Processing. Second ed. Addison-Wesley Publishing Company, Inc., Reading, Mass, USA.
Hasson A-C and Andrén O 1986 Below-grond plant production in a perennial grass ley (Festuca pratensis Huds.) assessed with different methods. J. Appl. Ecol. 23, 657–666.
Hansson A-C, Andrén O and Johansson R 1990 Rhizotronen — botemedlet mot rotlös forskning? Swed. Univ. Agric Sci. Fakta Mark/Växter 2, 4.
Heeraman D A and Juma N G 1993 A comparison of minirhizotron, core and monolith methods for quantifying barley (Hordeum vulgare L.) and fababean (Vicia faba L.) root distribution. Plant and Soil 148, 29–41.
Rasure J and Young P 1992 An Open Environment for Image Processing Software Development. SPIE/IS and T Symposium on Electronic Imaging. SPIE Proceedings Vol. 1659.
SAS Institute Inc. 1982 SAS User's Guide: Statistics. SAS Institute, Inc., Cary, NC, USA.
SAS Institute Inc. 1985 SAS/GRAPH User's Guide. SAS Institute, Inc., Cary, NC, USA.
Smucker A J M, Ferguson J C, DeBruyn W P, Belford R K and Ritchie J T 1987 Image analysis of video-recorded plant root system.In Minirhizotron Observtion Tubes: Methods and Applications for Measuring Rhizosphere Dynamics. Ed. H M Taylor. pp 67–80. ASA Spec. Pub. 50, Madison, WI, USA.
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Andrén, O., Elmquist, H. & Hansson, AC. Recording, processing and analysis of grass root images from a rhizotron. Plant Soil 185, 259–264 (1996). https://doi.org/10.1007/BF02257531
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DOI: https://doi.org/10.1007/BF02257531