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Full-Text Articles in Life Sciences
Seasonal Shifts Of Photosynthesis In Portulacaria Afra (L.) Jacq., Lonnie J. Guralnick, Patricia A. Rorabaugh, Zac Hanscom
Seasonal Shifts Of Photosynthesis In Portulacaria Afra (L.) Jacq., Lonnie J. Guralnick, Patricia A. Rorabaugh, Zac Hanscom
Arts & Sciences Faculty Publications
Portulacaria afra (L.) Jacq., a perennial facultative Crassulacean acid metabolism (CAM) species, was studied under natural photoperiods and temperatures in San Diego, California. The plants were irrigated every fourth day throughout the study period. Measurements of 14CO2 uptake, stomatal resistance, and titratable acidity were made periodically from July 1981 through May 1982. P. afra maintained C3 photosynthesis during the winter and the spring. Diurnal acid fluctuations were low and maximal 14CO2 uptake occurred during the day. The day/night ratio of carbon uptake varied from 5 to 10 and indicated little nocturnal CO2 uptake. CAM …
Wood Anatomy And Relationships Of Neowawraea (Euphorbiaceae), Dörthe S. Brandt, W. John Hayden
Wood Anatomy And Relationships Of Neowawraea (Euphorbiaceae), Dörthe S. Brandt, W. John Hayden
Honors Theses
Wood anatomy of three specimens of Neowawraea phyllanthoides Rock, a rare and endangered member of Euphorbiaceae endemic to the Hawaiian Islands, is described and compared with woods of other genera of subfamily Phyllanthoideae. Neowawraeahas often been associated or synonymized with Drypetes Vahl. Wood of Neowawraea is diffuse porous, perforation plates are simple, imperforate tracheary elements are thin-walled septate fiber-tracheids, rays are heterocellular and crystalliferous, and axial xylem parenchyma is restricted to a few scanty paratracheal and terminal cells. In several respects these results differ from earlier published descriptions of the wood of this taxon; these earlier descriptions are shown …