Taipei, Taiwan, Republic of China
Academia Sinica
Taipei, Taiwan, Republic of China
National Taiwan University
Buffalo, New York
State University of New York
Optical density of leaf
--Lin, B-L, Cheng, P-c, Sun, C-K
Recent development in laser technologies
offers a number of wavelength choices in multi-photon fluorescence and
harmonic generation microscopy. In order to assist in the selection of
excitation wavelengths and suitable fluorescent probes, we measured the
light attenuation of leaf in the spectral range of 250-2250nm. The spectrum
covers UV, visible and extended IR range to include the emission wavelengths
of Ti-sapphire (800nm), Nd-glass (1064nm), Cr-forsterite (1270nm), Cr-YAG
(1500nm), Er-glass (1550nm) and other ultra-fast IR lasers, as well as
the emission wavelengths of harmonic generations (second and third harmonic)
and fluorescence probes. A Hitachi spectrometer equipped with a scattered
light integrator was used in this study to measure the attenuation of maize
leaf (field grown mature leaf). Therefore, the attenuation spectrum is
mainly the result of absorption properties of leaf with minimum scattering
contribution. In order to minimize the scattering contribution due to air
spaces in the mesophyll, water logged leaf was used in the measurement.
The Figure
shows the attenuation spectrum (Cheng et al., SPIE Proceedings, vol. 4262)
of maize leaf. Note the high attenuation in UV as the result of proteins
and other organic compounds. The attenuation in the blue and red spectral
region is the result of chlorophylls and other photosynthetic pigments.
The attenuation in the IR range (>1400nm) is mainly due to the presence
of water in the leaf tissue. The translucent window of maize leaf suitable
for light microscopy is within the spectral range of 350-1400nm.
Supported by the National Science Council,
Republic of China under grant number: NSC-89-2311-B-001-032 (BLL), NSC-88-2811-B-001-0023
(PCC), NSC-89-2811-E-002-0058 (PCC), NSC-89-2215-E-002-064 (CKS).
Please Note: Notes submitted to the Maize Genetics Cooperation Newsletter may be cited only with consent of the authors.
Return to the MNL 75 On-Line Index
Return to the Maize Newsletter Index
Return to the MaizeGDB Homepage
