A critical study of methods for the determination of zinc in soils and plant materials
- Authors: Eve, Desmond John
- Date: 1955
- Subjects: Soils -- Zinc content , Soils -- Analysis , Plants -- Analysis
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:4468 , http://hdl.handle.net/10962/d1011770 , Soils -- Zinc content , Soils -- Analysis , Plants -- Analysis
- Description: Although it is only fairly recently that the importance of trace elements in plant nutrition has been established, enormous advances have been made in this field of research and numerous publications of considerable scientific and economic importance, dealing with the subject, have appeared. The physiological functions of zinc in promoting plant growth have not all been satisfactorily identified as yet. There are indications, however, that zinc acts as a catalyst or regulator in plant metabolism. It appears too, that the element plays some role in chlorophyll formation. Zinc deficiency is associated with leaf chlorosis and a general collapse of v ital processes. The analysis of leaves and soils has become an essential part of the study of the nutritional diseases of plants and it is imperative that accurate and reliable methods of analysis should be available. Intro. p. 1.
- Full Text:
A sample survey of farming types in the divisions of Albany and Bathurst
- Authors: Davies, R J
- Date: 1955
- Subjects: Agriculture -- South Africa -- Eastern Cape
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:4885 , http://hdl.handle.net/10962/d1014733
- Description: [From Introduction]. It is the purpose of this thesis to examine some of the broad relationships which exist between different land use types and farming practises on the one hand and the geographical environment on the other. The enquiry is confined to the study of a number of farm units which have been selected within the area enclosed by the District of Albany and Bathurst situated in the south-East coastal belt of the Cape Province. The procedure adapted conforms broadly to that of a project carried out in South America by R.S. Platt of the University of Chicago and embodied in hls book "Latin America, Countryside and United Regions." Platt's project, he notes, consists of a collection of "small field studies in a frame of complex generalisations." It does not aim to give a complete geographical account of the regions he selected for investigation, but is an attempt to enlarge geograpical understanding of the respective areas.
- Full Text:
An investigation into the insect ecology of citrus orchards, with special reference to citrus mussel scale (Lepidosaphes beckii newm.)
- Authors: Carnegie, Alistair John Michael
- Date: 1955
- Subjects: Citrus -- Diseases and pests -- South Africa -- Eastern Cape , Lepidosaphes
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:5905 , http://hdl.handle.net/10962/d1014637
- Description: In the course cf the last fifteen years the general lnsect ecology of citrus orchards in the Eastern Cape has provided the subject matter of four theses presented for the degree of M.Sc. of Rhodes University. The false codlin moth, Argyroploce leucotreta Meyr., formed the subject of a thesis by Horne in 1939. Then in 1941 the same insect formed the subject matter of a thesis by Harris. The general ecology of a citrus orchard, with special regard to the biological control of citrus red scale, Aonidiella aurantii Mask., was the subject matter of Whitehead's thesis in 1948. This was a much more general investigation than the preceding two theses, and touched on many more aspects of citrus ecology. Another thesis dealing with more general citrus ecology was that of Smithers in 1953.
- Full Text:
Studies of Hypnea spicifera
- Authors: Hewitt, Florence E
- Date: 1955
- Subjects: Marine algae
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:4271 , http://hdl.handle.net/10962/d1018234
- Full Text: