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A quantitative investigation of the absorption of certain cations by whole plants and plant tissues

- Cresswell, Christopher Frederick

Authors: Cresswell, Christopher Frederick
Date: 1959 , 2014-07-24
Subjects: Cations -- Absorption and adsorption , Plant tissues
Language: English
Type: Thesis , Masters , MSc
Identifier: vital:4262 , http://hdl.handle.net/10962/d1013335
Description: Introduction: Part 1. Greenhouse studies were conducted to investigate the absorption of sodium, potassium, calcium and magnesium by lemon seedlings. The plants were grown in controlled nutrient solutions and analysis of the plant material was made to determine the relationship between the four cations in the different plant organs. Results of the experiment may be summarized as follows:- The occurrence of leaf burn appeared to be associated with a low calcium content, together with a high sodium, potassium or sodium + potassium content. The development of the seedlings was shown to be markedly influenced by the level of calcium supply and to a much lesser degree by the level of potassium supplied. The concentration of sodium, potassium, calcium and magnesium in the stem and leaf varied with position of the tissues on the main axis. The level of sodium was found to influence the distribution of sodium in the leaves, and the sodium content of the leaf, stem and root tissues gave a good reflection of the level of sodium supplied. The effect of the sodium treatment on the uptake of potassium appeared to be dependent on the calcium content of the tissues. Sodium treatment was found not to affect the leaf calcium content. In the stem and root tissues the calcium content was reduced when the calcium level in the nutrient medium was low, and increased the calcium content of these two tissues at the higher level of calcium supply. The sodium supply was shown to reduce the leaf magnesium only slightly, and its affect on the magnesium content of the stem and root tissues was shown to be dependent on the level of calcium supplied. The potassium content of the leaves, stems and roots increased when the supply of potassium was raised. Increasing the potassium level in the nutrient supply was found to cause a very slight reduction in the sodium content of the leaf, but did not affect the sodium content of the stem and root. Potassium did not affect the calcium content of the leaves and increased the stem calcium when sodium was not present in the nutrient media in high concentrations. In the roots potassium only increase the calcium content at the upper level of calcium supply. The magnesium content of the leaf and stem tissues was reduced as the potassium supply was increased. In the roots the general trend was for the magnesium content to increase when the level of potassium treatment was raised. The calcium content of all the plant parts increased with a rise in the calcium supply, the stem and root tissues having a greater percentage increase than the leaves. The sodium content of the plant tissue was reduced as the level of calcium supply was raised. The leaf potassium content decreased with a higher calcium level of supply. In the stem and roots the potassium content was increased by doubling the calcium supply. The calcium treatment had no influence on the magnesium content of the foliage, but in the stem and root tissues a decrease in magnesium content resulted from an increase in the calcium supply. Part II Potato tuber tissue and carrot root tissue were used as experimental material in the investigation of sodium9 potassium9 and calcium uptake by storage tissue. It was shown that when the tissue disks are transferred from distilled water to a solution of salts there is a rapid initial uptake of cation which is neither particularly selective, nor related to metabolism, but dependent on the external concentration. On the other hand, the prolonged active accumulation of cation exhibits selectivity. Potassium absorption by potato tuber tissue was shown to be stimulated by sodium9 whereas the potassium and calcium absorption by carrot root tissue was shown to be reduced by sodium. Similarly the sodium absorption by the carrot root tissue was reduced by potassium, thus suggesting that the cations compete with one another for the same absorption mechanism.
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A study of the biology of the Jameson reservoir near Grahamstown, Cape Province

- Darbyshire, John Frederick

Authors: Darbyshire, John Frederick
Date: 1959
Language: English
Type: Thesis , Masters , MSc
Identifier: http://hdl.handle.net/10962/6784 , vital:21179
Description: 1. This thesis is an ecological study of a South African water storage reservoir and it’s tributary streams. 2. A brief description of the reservoir, the surrounding vegetation, superficial geological strata, soils and early history of the reservoir is given in Chapter I. 3. The surrounding vegetation is discussed in some detail in Chapter II. The zonation of the plants and the influence of water upon it are discussed. 4. The results of the regular investigations of the physicochemical environment are presented in Appendix 1 and the salient points noted in Chapter III. 5. The species of algae collected are listed in Appendix 2 and in Chapter IV are discussed in relation to habitat and abundance. 6. The animals are dealt with in a similar manner in Chapter V. Under 'Discussion and Conclusions' in Chapter VI an attempt is made to review the findings and discuss their significance.
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A study of the heroine in certain Victorian novels

- Addecott, Grahame John

Authors: Addecott, Grahame John
Date: 1959
Subjects: English fiction -- 19th century -- History and criticism , Heroines in literature
Language: English
Type: Thesis , Masters , MA
Identifier: vital:2319 , http://hdl.handle.net/10962/d1013374
Description: During the reign of Queen Victoria was seen the gradual emergence of the emancipated woman. The idea that women were innocent beings who must be kept from real knowledge of the world died hard, however, and to the end of the era there were many who repudiated the very concept of emancipation whether in literature or life. Coupled with the chivalrous, idealistic concept of womanhood was Victorian respectability, and it is not surprising that in the earlier Victorian novels we see clearly the idealistic concept of women and the effects of the cult of respectability. To illustrate my theme, of the gradual change in the concept of the novel which naturally kept pace, more or less, with the progress the emancipation of women was making, I have chosen one novel from each of seven great Victorian novelists whose works span the whale era. The only exception I have made is with Charlotte Bronte. In her case the heroines of two of her novels are discussed mainly because she is the first Victorian novelist to sound a note of protest against the then conventional concept of the heroine.
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A study of the predators and parasites of Planococcus citri (Risso) (Homoptera) on vines in the Western Cape Province, South Africa

- Whitehead, Vincent Booth

Authors: Whitehead, Vincent Booth
Date: 1959
Subjects: Hemiptera , Parasites , Insect pests -- Biological control , Grapes -- Diseases and pests
Language: English
Type: Thesis , Masters , MSc
Identifier: vital:5896 , http://hdl.handle.net/10962/d1013425
Description: [Introduction] In the Western Cape Province the mealybug, Planococcus citri (Risso), was first reported on vines in 1930 by Joubert (1943a). By 1935 this mealybug had spread to the Hex River Valley, and subsequently to all the main table grape producing areas of the Western Cape Province. At present Pl. citri is the most important insect pest of the table grape industry and can, if not effectively controlled, result in a loss of at least five per cent of the export table grape crop (Kriegler, 1954). Some preliminary work on the natural enemies of Pl. citri on vines was carried out by Stubbings in 1948, but no further work of this nature has been undertaken in this area since then. The fact that the natural enemies can be an effective check to this mealybug on vines in the Western Cape Province has been known for a number of years (Potgieter, 1937; Hattingh, 1943; Joubert, 1943a; Myburgh, 1951). The present work is an attempt to obtain some basic knowlege of the population fluctuations of the insects concerned in this biological control. Surveys undertaken have shown that there is a complex of primary, secondary and possibly tertiary Hynenopterous parasites associated with Pl. citri. The presence of hyperparasites reduces the efficiency of the primary parasitic Hymenoptera. The usefulness of these primary parasites is further reduced as they only occur in effective numbers for a short period of the year. On the other hand, although attacked by some parasites, the numerous coccinellids found preying on Pl. citri are of more importance in reducing the mealybug populations, as they are present on the vines in effective numbers for the greater part of the year.
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A study of the relationship between the poetry and criticism of Ezra Pound 1908-1920

- De Villiers, André Rex Wepener

Authors: De Villiers, André Rex Wepener
Date: 1959
Subjects: Pound, Ezra, 1885-1972 -- Criticism and interpretation
Language: English
Type: Thesis , Masters , MA
Identifier: vital:2317 , http://hdl.handle.net/10962/d1013320
Description: From the preface: The purpose of this thesis is exposition rather than criticism. Pound's position in the hierarchy of the 'New Criticism' would provide an extremely interesting subject; but I have rather tried to outline; the standards which he has laid down as being central in the technics of good poetry and to show how closely he has adhered to them in his own verse. I have limited the period to be discussed because all of the essential principles which he employs in his writing after 1920 are discernible in the body of his work published before that date.
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Acacia Karoo - Eastern Cape (South Arica)

- Skead, C J (Cuthbert John)

Authors: Skead, C J (Cuthbert John)
Date: 1959
Subjects: Acacia karroo -- South Africa , Trees -- South Africa
Language: English
Type: mixed material , essay
Identifier: http://hdl.handle.net/10962/109187 , vital:33083
Description: Transcript: "Acacia karroo 01. 11. 1959. At Bashee Bridge, between Idutywa and Umtata, Transkei, trees just beginning to flower. One fairly advanced. At Kei bridge on the Transkei-Komga border only a few yellow dots of flower appearing; also as King William's Town. The winter and spring had been good this year. Last-week in May and into June. Autumnal tints fine. Trees change to a rich gold, made lovelier by the fern-like nature of the foliage. Colour varies from yellow to gold. July. Branches now bare August. Branches mostly bare still but where a tree is growing in a damp area, new shoots are staring 28.12.1958. Travelling between Grahamstown and King William's Town. Acacias in the Great Fish River valley were well out in flower, far in advance of those near Grahamstown, in the Keiskamma River valley, and at King William's Town. Always some trees in an area flower in advance of the rest and, always, certain trees surpass all others Sept.1960. Trees burst into leaf in about second week despite severe drought. Rather irregular as between tree and tree with some trees still in their old dark foliage and some still leafless after the winter, 16.10.1960. A few puffs of flower coming out. Otherwise only rough, unopened flower buds 1 June 1961. In the King William's Town bushveld many of the Acacia trees, now almost leafless or only sparsely leaved, have appearance of spume-like scum spread over them, a dirty off- white mass. But this is an illusion; it is caused by the fuzzy, wispy seed-covers of Clematis now in full seed.”
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