TY  - JOUR
AU  - Biskup, B.
AU  - Scharr, H.
AU  - Schurr, U.
AU  - Rascher, U.
TI  - A stereo imaging system for measuring structural parameters of plant canopies
JO  - Plant, cell & environment
VL  - 30
SN  - 0140-7791
CY  - Oxford [u.a.]
PB  - Wiley-Blackwell
M1  - PreJuSER-52406
SP  - 1299 - 1308
PY  - 2007
N1  - Record converted from VDB: 12.11.2012
AB  - Plants constantly adapt their leaf orientation in response to fluctuations in the environment, to maintain radiation use efficiency in the face of varying intensity and incidence direction of sunlight. Various methods exist for measuring structural canopy parameters such as leaf angle distribution. However, direct methods tend to be labour-intensive, while indirect methods usually give statistical information on stand level rather than on individual leaves. We present an area-based, binocular stereo system composed of commercially available components that allows three-dimensional reconstruction of small- to medium-sized canopies on the level of single leaves under field conditions. Spatial orientation of single leaves is computed with automated processes using modern, well-established stereo matching and segmentation techniques, which were adapted for the properties of plant canopies, providing high spatial and temporal resolution (angle measurements with an accuracy of approx. +/-5 degrees and a maximum sampling rate of three frames per second). The applicability of our approach is demonstrated in three case studies: (1) the dihedral leaflet angle of an individual soybean was tracked to monitor nocturnal and daytime leaf movement showing different frequencies and amplitudes; (2) drought stress was diagnosed in soybean by quantifying changes in the zenith leaflet angle distribution; and (3) the diurnal course of the zenith leaf angle distribution of a closed soybean canopy was measured.
KW  - Circadian Rhythm
KW  - Disasters
KW  - Image Processing, Computer-Assisted: methods
KW  - Imaging, Three-Dimensional
KW  - Plant Leaves: anatomy & histology
KW  - Soybeans: anatomy & histology
KW  - Time Factors
KW  - J (WoSType)
LB  - PUB:(DE-HGF)16
C6  - pmid:17727419
UR  - <Go to ISI:>//WOS:000249423300008
DO  - DOI:10.1111/j.1365-3040.2007.01702.x
UR  - https://juser.fz-juelich.de/record/52406
ER  -