Access the full text.
Sign up today, get DeepDyve free for 14 days.
Loading next page...
/lp/wiley/indirect-determination-of-leaf-area-index-of-sugar-beet-canopies-in-LmGpGWm780
References (8)
-
A. Lang (1987)
Simplified estimate of leaf area index from transmittance of the sun's beamAgricultural and Forest Meteorology, 41
-
R. Anderssen, D. Jackett, D. Jupp, J. Norman (1985)
Interpretation of and simple formulas for some key linear functionals of the foliage angle distributionAgricultural and Forest Meteorology, 36
-
J. Welles, J. Norman (1991)
Instrument for Indirect Measurement of Canopy ArchitectureAgronomy Journal, 83
-
J. Monteith (1965)
Light Distribution and Photosynthesis in Field CropsAnnals of Botany, 29
-
A. Lang (1986)
Estimation of leaf area index from transmission of direct sunlight in discontinuous canopiesAgricultural and Forest Meteorology, 37
-
A. Lang, Yueqin Xiang, J. Norman (1985)
Crop structure and the penetration of direct sunlightAgricultural and Forest Meteorology, 35
-
Steven Perry, Alistair Fraser, Dennis Thomson, John Norman (1988)
Indirect sensing of plant canopy structure with simple radiation measurementsAgricultural and Forest Meteorology, 42
-
F. Baret, B. Andrieu, M. Steven (1993)
Gap frequency and canopy architecture of sugar beet and wheat cropsAgricultural and Forest Meteorology, 65
- Publisher
- Wiley
- Copyright
- Copyright © 1995 Wiley Subscription Services, Inc., A Wiley Company
- ISSN
- 0931-2250
- eISSN
- 1439-037X
- DOI
- 10.1111/j.1439-037X.1995.tb01102.x
- Publisher site
- See Article on Publisher Site
Abstract
The determination of the leaf area index of sugar beet canopies by using direct measurement techniques is very laborious. Indirect measurement techniques based on the theory of gap fractions offer a non‐destructive and rapid determination of the leaf area index. In this study the performance of the LAI‐2000 instrument from LI‐COR1 which measures the gap fraction at five zenith angle classes with an upward looking sensor was compared to a direct determination. A thinning test and two measurement series in sugar beet with different population densities and varied nitrogen application were conducted in 1992 and 1993 at the site of Göttingen. The direct determination of leaf area index was based on a destructive sampling of leaves and measurements with a Delta‐T2 image analysis system (DIAS). The results of the thinning test and the measurement series in 1992 did not indicate a significant difference between the LAI‐2000 and the direct determination. With correlation coefficients of 0.98 and 0.95 respectively, the relation between the two techniques was very close. The measurement series of 1993 showed a worse correspondence. In general the values of the LAI‐2000 measurements tended to be a bit lower than those of the direct determination. The leaf area index of sugar beet can be determined with sufficient accuracy using the LAI‐2000 instrument if light conditions are favourable and if the measurement procedure is adapted correctly.
Journal
Journal of Agronomy and Crop Science – Wiley
Published: Apr 1, 1995