Influence of Translocation on Photosynthetic Efficiency of Phaseolus vulgaris L

Measurements of net photosynthesis show that in Phaseolus vulgaris L. the cultivar Michelite-62 exceeds the cultivar Red Kidney in net CO2 uptake by 23 to 31%. Data on translocation of pulse label indicate that export of a pulse of photosynthetically assimilated 14C from the source leaf of either M-...

Full description

Saved in:
Bibliographic Details
Published in:Plant physiology (Bethesda) 1973-11, Vol.52 (5), p.412-415
Main Authors: Phyllis Liu, Wallace, D. H., Ozbun, J. L.
Format: Article
Language:English
Subjects:
Flasks
Freezing
Kidneys
Leaves
Petioles
Photosynthesis
Plant veins
Plants
Radioactive decay
Radiocarbon
Citations: Items that cite this one
Online Access:Get full text
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:Measurements of net photosynthesis show that in Phaseolus vulgaris L. the cultivar Michelite-62 exceeds the cultivar Red Kidney in net CO2 uptake by 23 to 31%. Data on translocation of pulse label indicate that export of a pulse of photosynthetically assimilated 14C from the source leaf of either M-62 or Red Kidney follows an exponential pattern and shows an initial rapid phase followed by a second slower phase. The steeper slope for both phases in M-62 suggests its rate of translocation of pulse label is higher than that of Red Kidney. Furthermore, only 38% of the 14C remains in the leaf of M-62 after 8 hours, while Red Kidney retains up to 60% of the label. Leaf autoradiographs obtained after pulse labeling demonstrate a much faster rate of vein loading in M-62 and are considered evidence for the higher translocation efficiency of M-62. These results provide evidence for a positive correlation between photosynthetic efficiency and translocation efficiency in M-62 and Red Kidney and give support to our hypothesis that translocation is one of the important physiological factors controlling the varietal differences in photosynthetic efficiency in Phaseolus vulgaris.
ISSN:0032-0889
1532-2548
DOI:10.1104/pp.52.5.412