Port Elizabeth History: A Select Annotated Bibliography
- Authors: Baines, Gary F
- Date: 1998
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/125742 , vital:35813 , https://doi.10.1080/02582479808671323
- Description: When I commenced my work on aspects of Port Elizabeth’s history in the late 1980s, there was no body of scholarly literature on which to draw. Since thena number of significant publications, both periodical articles and books, as well as theses have appeared, and something of a corpus of works on the city now exists. It seems appropriate to take stock of the current state of Port Elizabeth’s historiography by compiling a bibliography.
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- Date Issued: 1998
Symplastic solute transport and avocado fruit development : a decline in cytokinin/ABA ratio is related to appearance of the Hass small fruit variant
- Authors: Moore-Gordon, Clive S , Cowan, Keith A , Bertling, Isa , Botha, Christiaan E J , Cross, Robin H M
- Date: 1998
- Language: English
- Type: Article
- Identifier: vital:6525 , http://hdl.handle.net/10962/d1005959
- Description: Studies on the effect of fruit size on endogenous ABA and isopentenyladenine (iP) in developing avocado (Persea americana Mill. cv. Hass) fruit revealed that ABA content was negatively correlated with fruit size whilst the iP/ABA ratio showed a linear relationship with increasing size of fruit harvested 226 d after full bloom. The effect of this change in hormone balance on the relationship between symplastic solute transport and appearance of the small fruit variant was examined following manipulation of the endogenous cytokinin (CK)/ABA ratio. Application of ABA caused seed coat senescence and retarded fruit growth but these effects were absent in fruit treated with equal amounts of ABA plus iP. Thus, the underlying physiological mechanisms associated with ABA-induced retardation of Hass avocado fruit growth appeared to be inextricably linked to a decline in CK content and included: diminution of mesocarp and seed coat plasmodesmatal branching, gating of mesocarp and seed coat plasmodesmata by deposition of electron dense material in the neck region, abolishment of the electrochemical gradient between mesocarp and seed coat parenchyma, and arrest of cell-to-cell chemical communication.
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- Date Issued: 1998