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Water relations, thallus structure and photosynthesis in Negev Desert lichensThe role of lichen thallus structure in water relations and photosynthesis was studied in Ramalina maciformis (Del.) Bory and Teloschistes lacunosus (Rupr.) Sav. Water-vapour adsorption and photosynthesis are dependent upon thallus integrity and are significantly lower in crushed thalli. Cultured phycobiont (Trebouxia sp.) cells are capable of photosynthesis over the same relative humidity range (> 80% RH) as are intact lichens. Thus, water-vapour adsorption by the thallus and physiological adaptation of the phycobiont contribute to the ability of these lichens to photosynthesize in an arid environment. Despite differences in their anatomical structure and water-uptake characteristics, their CO2 incorporation is similar. The two lichens use liquid water differently and they occupy different niches.
Document ID
20040112166
Document Type
Reprint (Version printed in journal)
Authors
Palmer, R. J. Jr (Polar Desert Research Center, Florida State University Tallahassee, FL 32306-2043, United States)
Friedmann, E. I.
Date Acquired
August 21, 2013
Publication Date
January 1, 1990
Publication Information
Publication: The New phytologist
Volume: 116
ISSN: 0028-646X
Subject Category
Exobiology
Funding Number(s)
CONTRACT_GRANT: BSR86-12256
CONTRACT_GRANT: NSG 7337
CONTRACT_GRANT: DPP 83-14180
Distribution Limits
Public
Copyright
Other
Keywords
Non-NASA Center
NASA Discipline Exobiology
NASA Discipline Number 52-30
NASA Program Exobiology