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Characterization of the Bean Pod as a Photosynthetic Organ 1
Author(s) -
Crookston R. K.,
O'Toole J.,
Ozbun J. L.
Publication year - 1974
Publication title -
crop science
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.76
H-Index - 147
eISSN - 1435-0653
pISSN - 0011-183X
DOI - 10.2135/cropsci1974.0011183x001400050030x
Subject(s) - point of delivery , phaseolus , photosynthesis , biology , botany , rubisco , chloroplast , horticulture , biochemistry , gene
The photosynthetic characteristics of the pod of Phaseolus vulgaris L. cv. ‘Redkote’ were determined by measurements of CO 2 exchange, enzyme activities, and anatomical observations. Per unit area, the pod incorporated only 5 to 9% as much atmospheric CO 2 as its subtending leaf. It appeared to be recycling substantial amounts of internally‐released CO 2 however, and its total CO 2 ‐fixing capacity was estimated to be 26% that of the leaf. Enzyme activity measurements showed that the pod had 40% as much ribulose diphosphate carboxylase and glycolate oxidase activity and over 700% as much malate dehydrogenase activity per unit area as the leaf. Cells in the outer half of the pod wall had numerous chloroplasts which increased in frequency and starch content with proximity to vascular tissue. There were no plastids in the inner half of the pod wall. The pod surface contained 25% as many stomata per unit area as the lower surface of the leaf. Some of the pod stomata appeared to be partially or completely obstructed.