Volume 96, Issue 2 p. 249-256
Free Access

ECOPHYSIOLOGICAL STUDIES OF THE LICHEN, PARMELIA PRAESIGNIS Nyl.

POPULATION VARIATION AND THE EFFECT OF STORAGE CONDITIONS

S. O. LINK

S. O. LINK

Department of Botany and Microbiology, Arizona State University, Tempe, Arizona 85287, USA

Range Science Department, Utah State University, Logan. Utah, USA, 84322.

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T. H. NASH III

T. H. NASH III

Department of Botany and Microbiology, Arizona State University, Tempe, Arizona 85287, USA

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First published: February 1984
Citations: 10

Summary

Losses in photosynthetic ability were observed in the lichen, Parmelia praesignis Nyl., over a 2-week period under three out of four different combinations of temperature and hydration conditions during storage. At a constant daytime temperature of 16 °C, lichens which were wetted even, few days retained more photosynthetic ability than did lichens wetted everyday. Lichens which were maintained under a varying range of temperatures (12 to 26 °C) retained most of their photosynthetic ability, with the material wetted daily eventually losing 40% of its ability. The material wetted every few days did not lose a significant amount of photosynthetic ability. Lichen material maintained at a temperature of 33 °C and wetted everyday lost all photosynthetic ability after 3 d.

Photosynthetic ability was found to be normally distributed with a mean of 3.2 mg CO2 g−1 and a standard deviation of 0.65 mg CO2 g−1 h−1 when based on the experimental results from 25 randomly selected sets of thallus tips.