You are not currently logged in.
Access your personal account or get JSTOR access through your library or other institution:
If You Use a Screen ReaderThis content is available through Read Online (Free) program, which relies on page scans. Since scans are not currently available to screen readers, please contact JSTOR User Support for access. We'll provide a PDF copy for your screen reader.
Endogenous Short Period Rhythms in the Movements of Unifoliate Leaves of Phaseolus angularis Wight
D. K. Alford and T. W. Tibbitts
Vol. 47, No. 1 (Jan., 1971), pp. 68-70
Published by: American Society of Plant Biologists (ASPB)
Stable URL: http://www.jstor.org/stable/4262306
Page Count: 3
Since scans are not currently available to screen readers, please contact JSTOR User Support for access. We'll provide a PDF copy for your screen reader.
Preview not available
Rhythmic rotational movements with the midvein as the axis have been observed in the unifoliate leaves of Phaseolus angularis Wight grown under controlled environmental conditions with continuous light. The mean period of this movement for all leaves was 53.2 ± 4.3 minutes and remained constant as the leaf matured, except after removal of the apical meristem and emerging trifoliate leaf when the period increased by about 5 minutes. The amplitude of the movement also remained constant as the leaf matured. These rotational movements were pronounced when the leaf blade was in a horizontal position and were not evident during the downward or "sleep" movements of the leaf. This movement began 3 days after leaf unfolding and continued for at least 6 days. It was most pronounced at the time of inflection of the leaf length growth curve after the logarithmic phase of growth.
Plant Physiology © 1971 American Society of Plant Biologists (ASPB)