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Full-Text Articles in Physical Sciences and Mathematics
Functional Transition In The Floral Receptacle Of The Sacred Lotus (Nelumbo Nucifera): From Thermogenesis To Photosynthesis, R. E. Miller, J. R. Watling, Sharon A. Robinson
Functional Transition In The Floral Receptacle Of The Sacred Lotus (Nelumbo Nucifera): From Thermogenesis To Photosynthesis, R. E. Miller, J. R. Watling, Sharon A. Robinson
Faculty of Science - Papers (Archive)
The receptacle of the sacred lotus is the main source of heat during the thermogenic stage of floral development. Following anthesis, it enlarges, greens and becomes a fully functional photosynthetic organ. We investigated development of photosynthetic traits during this unusual functional transition. There were two distinct phases of pigment accumulation in receptacles. Lutein and photoprotective xanthophyll cycle pigments accumulated first with 64% and 95% of the maximum, respectively, present prior to anthesis. Lutein epoxide comprised 32% of total carotenoids in yellow receptacles, but declined with development. By contrast, more than 85% of maximum total chlorophyll, β-carotene and Rubisco were produced …
Preliminary Investigations Of Pigment Responses To Phylloxera Infestation, A L. Blanchfield, K S. Powell, Sharon A. Robinson
Preliminary Investigations Of Pigment Responses To Phylloxera Infestation, A L. Blanchfield, K S. Powell, Sharon A. Robinson
Faculty of Science - Papers (Archive)
Early detection of grape phylloxera (Daktulosphaira vitifoliae) infestation is vital for the implementation of post-outbreak quarantine in Australia. Remote sensing systems exploit changes in leaf pigment content associated with plant stress and offer a real possibility of a phylloxera-specific detection system. Pre-visual, symptomatic changes in the pigment content of phylloxera-infested grapevine leaves were investigated using high performance liquid chromatography (HPLC) as a potential aid to improve current phylloxera detection methods. A glasshouse trial was established to characterize the response of two grapevine varieties, Vitis vinifera ‘Cabernet Sauvignon’ and ‘Shiraz’, to phylloxera infestation, in a controlled environment. Field trials …
Climate Change Manipulations Show Antarctic Flora Is More Strongly Affected By Elevated Nutrients Than Water, J. Wasley, Sharon A. Robinson, C. E. Lovelock, M. Popp
Climate Change Manipulations Show Antarctic Flora Is More Strongly Affected By Elevated Nutrients Than Water, J. Wasley, Sharon A. Robinson, C. E. Lovelock, M. Popp
Faculty of Science - Papers (Archive)
Climate change is expected to affect the high latitudes first and most severely, rendering Antarctica one of the most significant baseline environments for the study of global climate change. The indirect effects of climate warming, including changes to the availability of key environmental resources, such as water and nutrients, are likely to have a greater impact upon continental Antarctic terrestrial ecosystems than the effects of fluctuations in temperature alone. To investigate the likely impacts of a wetter climate on Antarctic terrestrial communities a multi-season, manipulative field experiment was conducted in the floristically important Windmill Islands region of East Antarctica. Four …
Impact Of Changes In Natural Uv Radiation On Pigment Composition, Physiological And Morphological Characteristics Of The Antarctic Moss, Grimmia Antarctici., Sharon A. Robinson, J. D. Turnbull, C. E. Lovelock
Impact Of Changes In Natural Uv Radiation On Pigment Composition, Physiological And Morphological Characteristics Of The Antarctic Moss, Grimmia Antarctici., Sharon A. Robinson, J. D. Turnbull, C. E. Lovelock
Faculty of Science - Papers (Archive)
The impact of ambient UV-B radiation on the endemic bryophyte, Grimmia antarctici, was studied over 14 months in East Antarctica. Over recent decades, Antarctic plants have been exposed to the largest relative increase in UV-B exposure as a result of ozone depletion. We investigated the effect of reduced UV and visible radiation on the pigment concentrations, surface reflectance and physiological and morphological parameters of this moss. Plexiglass screens were used to provide both reduced UV levels (77%) and a 50% decrease in total radiation. The screen combinations were used to separate UV photoprotective from visible photoprotective strategies, since these bryophytes …
Surface Reflectance Properties Of Antarctic Moss And Their Relationship To Plant Species, Pigment Composition And Photosynthetic Function, C. E. Lovelock, Sharon A. Robinson
Surface Reflectance Properties Of Antarctic Moss And Their Relationship To Plant Species, Pigment Composition And Photosynthetic Function, C. E. Lovelock, Sharon A. Robinson
Faculty of Science - Papers (Archive)
We investigated how surface reflectance properties and pigment concentrations of Antarctic moss varied over species, sites, microtopography, and with water content. We found that species had significantly different surface reflectance properties, particularly in the region of the red edge (approximately 700 nm), but this did not correlate strongly with pigment concentrations. Surface reflectance of moss also varied in the visible region and in the characteristics of the red edge over different sites. Reflectance parameters, such as the Photochemical Reflectance Index (PRI) and Cold Hard Band (CBH) were useful discriminators of site, microtopographic position and water content. The PRI was correlated …