Abstract
There have been conflicting reports on the photosynthetic mode of cassava (Manihot esculenta Crantz). It has been suggested that cassava is a C3-C4 intermediate plant and, alternatively, that it is a C3 plant. Glycine decarboxylase (GDC), a photorespiratory enzyme, is known to exhibit different patterns of intercellular distribution between C3-C4 intermediate and C3 leaves. In order to elucidate the photosynthetic mode of cassava, we investigated the localization of GDC in the leaves of three cultivars by immunogold electron microscopy and the anatomical structures of the leaves. The leaves of cassava are essentially hypostomatous, and the photosynthetic tissues consist of palisade mesophyll cells (PMCs), spongy mesophyll cells (SMCs) and bundle sheath cells (BSCs). Although the BSCs include centrifugally located chloroplasts, they show no increase in mitochondrial frequency. Labeling specific for GDC was found on all mitochondria of all three types of cell. However, the density of labeling in the PMGs was always higher than in the SMCs and BSCs. In leaves that developed under a water deficit, the difference in labeling density became even clearer. These data suggest that at least the cultivars of cassava examined here are not C3-C4 intermediates and should be regarded as C3 plants. However, the intercellular differences in the level of accumulation of GDC seem to merit further investigation with respect to an internal gradient of photorespiratory capacity in the leaves.
| Original language | English |
|---|---|
| Pages (from-to) | 268-278 |
| Number of pages | 11 |
| Journal | Japanese Journal of Crop Science |
| Volume | 66 |
| Issue number | 2 |
| DOIs | |
| Publication status | Published - Jan 1 1997 |
| Externally published | Yes |
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All Science Journal Classification (ASJC) codes
- Food Science
- Agronomy and Crop Science
- Genetics
Cite this
The intercellular distribution of glycine decarboxylase in leaves of cassava in relation to the photosynthetic mode and leaf anatomy. / Osamu, Ueno; Agarie, Sakae.
In: Japanese Journal of Crop Science, Vol. 66, No. 2, 01.01.1997, p. 268-278.Research output: Contribution to journal › Article
}
TY - JOUR
T1 - The intercellular distribution of glycine decarboxylase in leaves of cassava in relation to the photosynthetic mode and leaf anatomy
AU - Osamu, Ueno
AU - Agarie, Sakae
PY - 1997/1/1
Y1 - 1997/1/1
N2 - There have been conflicting reports on the photosynthetic mode of cassava (Manihot esculenta Crantz). It has been suggested that cassava is a C3-C4 intermediate plant and, alternatively, that it is a C3 plant. Glycine decarboxylase (GDC), a photorespiratory enzyme, is known to exhibit different patterns of intercellular distribution between C3-C4 intermediate and C3 leaves. In order to elucidate the photosynthetic mode of cassava, we investigated the localization of GDC in the leaves of three cultivars by immunogold electron microscopy and the anatomical structures of the leaves. The leaves of cassava are essentially hypostomatous, and the photosynthetic tissues consist of palisade mesophyll cells (PMCs), spongy mesophyll cells (SMCs) and bundle sheath cells (BSCs). Although the BSCs include centrifugally located chloroplasts, they show no increase in mitochondrial frequency. Labeling specific for GDC was found on all mitochondria of all three types of cell. However, the density of labeling in the PMGs was always higher than in the SMCs and BSCs. In leaves that developed under a water deficit, the difference in labeling density became even clearer. These data suggest that at least the cultivars of cassava examined here are not C3-C4 intermediates and should be regarded as C3 plants. However, the intercellular differences in the level of accumulation of GDC seem to merit further investigation with respect to an internal gradient of photorespiratory capacity in the leaves.
AB - There have been conflicting reports on the photosynthetic mode of cassava (Manihot esculenta Crantz). It has been suggested that cassava is a C3-C4 intermediate plant and, alternatively, that it is a C3 plant. Glycine decarboxylase (GDC), a photorespiratory enzyme, is known to exhibit different patterns of intercellular distribution between C3-C4 intermediate and C3 leaves. In order to elucidate the photosynthetic mode of cassava, we investigated the localization of GDC in the leaves of three cultivars by immunogold electron microscopy and the anatomical structures of the leaves. The leaves of cassava are essentially hypostomatous, and the photosynthetic tissues consist of palisade mesophyll cells (PMCs), spongy mesophyll cells (SMCs) and bundle sheath cells (BSCs). Although the BSCs include centrifugally located chloroplasts, they show no increase in mitochondrial frequency. Labeling specific for GDC was found on all mitochondria of all three types of cell. However, the density of labeling in the PMGs was always higher than in the SMCs and BSCs. In leaves that developed under a water deficit, the difference in labeling density became even clearer. These data suggest that at least the cultivars of cassava examined here are not C3-C4 intermediates and should be regarded as C3 plants. However, the intercellular differences in the level of accumulation of GDC seem to merit further investigation with respect to an internal gradient of photorespiratory capacity in the leaves.
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U2 - 10.1626/jcs.66.268
DO - 10.1626/jcs.66.268
M3 - Article
VL - 66
SP - 268
EP - 278
JO - Japanese Journal of Crop Science
JF - Japanese Journal of Crop Science
SN - 1349-0990
IS - 2
ER -