Full Text Available

Note: Clicking the button above will open the full text document at the original institutional repository in a new window.

'n Biologiese ondersoek van Tylosema esculentum

Dissertation (MSc)--University of Pretoria, 1990.

Saved in:
Bibliographic Details
Other Authors: Coetzer, Louw A.
Format: Thesis
Language:Afrikaans
Published: University of Pretoria 2022
Subjects:
Tags: Add Tag
No Tags, Be the first to tag this record!
_version_ 1867613469486874624
access_status_str Open Access
author2 Coetzer, Louw A.
author_browse Coetzer, Louw A.
author_facet Coetzer, Louw A.
collection Thesis
dc_rights_str_mv © 2020 University of Pretoria. All rights reserved. The copyright in this work vests in the University of Pretoria. No part of this work may be reproduced or transmitted in any form or by any means, without the prior written permission of the University of Pretoria.
description Dissertation (MSc)--University of Pretoria, 1990.
format Thesis
id oai:repository.up.ac.za:2263/85507
institution University of Pretoria (South Africa)
language Afrikaans
last_indexed 2026-06-10T12:36:38.728Z
license_str Other — see source repository
provenance_str_mv Harvested via OAI-PMH from UPSpace — University of Pretoria Institutional Repository
publishDate 2022
publishDateRange 2022
publishDateSort 2022
publisher University of Pretoria
publisherStr University of Pretoria
record_format dspace
source_str UPSpace — University of Pretoria Institutional Repository
spelling oai:repository.up.ac.za:2263/85507 'n Biologiese ondersoek van Tylosema esculentum Coetzer, Louw A. Robbertse, P.J. (Petrus Johannes), 1932- De Frey, Helena Maria UCTD Biologiese ondersoek Tylosema esculentum Dissertation (MSc)--University of Pretoria, 1990. Tylosema esculentum (Schweinf.) Schreiber belongs to the family Caesalpiniaceae in the tribe Cercideae Bronn. The species is distributed throughout Southern Africa. The combination of climate and soiltype with the occurrence of lime and dolomite seem to be determinating factors in the distribution of the species. T esculentum is a perennial geophyte with an underground tuber bearing ephemeral climbing or creeping stems. Vegetative growth and development occurs from August to May. The main stems and 1st order-lateral stems are mainly responsible for the first high intensity flowering phase during November while the 2nd order-lateral stems are responsible for the second high intensity flowering phase during January. No significant difference (p<0.05) is to be found between the development of Pin and Thrum flowering plants. T esculentum has chasmogamic, entomophylous flowers which are zygomorphic and distylous. Nectar production in the hipantium is the primary attractant of pollinators and is supplemented by two secondary attractants, viz. the bright yellow flower colour and their mild sweet aroma. The stigmas are funnel-shaped, papillate and wet. Anthesis takes 18 to 21 hours and the flowers have an average life expectancy of four days. The peak of stigma receptivity is on days two and three after anthesis. An average of 29 088 pollen grains (from only two fertile anthers) are produced per flower and a pollen viability of 25.3% for pin flowers and 21 .3% for thrum flowers was obtained using the in vitro test method. A viscous, polisaccharide and lipid-like anther-mucilage is released simultaneously with the pollen during anther dehiscence. This anther-mucilage is produced within the anther-connective tissue and is analogous, in terms of pollination ecology, to pollenkitt and viscin threads. No pre-zygotic self-incompatibility system was found. A high level of outbreeding is maintained through reciprocal herkogamy and incomplete protogyny. A contributing factor may be the availability of pollen on the first day of anthesis only, as a result of the hardening of the anther-mucilage, while the peak of stigma receptivity is on days two and three after anthesis. The possibility of the presence of a post-zygotic late-acting self-incompatibility system is, however, not completely ruled out. Plant Science MSc Unrestricted 2022-05-17T11:22:04Z 2022-05-17T11:22:04Z 2021/10/07 1990 Dissertation * https://repository.up.ac.za/handle/2263/85507 af © 2020 University of Pretoria. All rights reserved. The copyright in this work vests in the University of Pretoria. No part of this work may be reproduced or transmitted in any form or by any means, without the prior written permission of the University of Pretoria. application/pdf University of Pretoria
spellingShingle UCTD
Biologiese ondersoek
Tylosema esculentum
'n Biologiese ondersoek van Tylosema esculentum
title 'n Biologiese ondersoek van Tylosema esculentum
title_full 'n Biologiese ondersoek van Tylosema esculentum
title_fullStr 'n Biologiese ondersoek van Tylosema esculentum
title_full_unstemmed 'n Biologiese ondersoek van Tylosema esculentum
title_short 'n Biologiese ondersoek van Tylosema esculentum
title_sort n biologiese ondersoek van tylosema esculentum
topic UCTD
Biologiese ondersoek
Tylosema esculentum
url https://repository.up.ac.za/handle/2263/85507