Isoenzyme analysis of five endemic and one widespread Kniphofia species (Asphodelaceae) of Ethiopia

  • Tilahun Teklehaymanot Institute of Pathobiology, Addis Ababa University, PO Box 56478, Addis Ababa, Ethiopia
  • Endashaw Bekele Faculty of Science, Addis Ababa University, PO Box 3434, Addis Ababa, Ethiopia
  • Sebsebe Demissew Faculty of Science, Addis Ababa University, PO Box 3434, Addis Ababa, Ethiopia
  • Inger Nordal Inger Nordal, University of Oslo, PO Box 1066 Blindern, N-0316 Oslo, Norway
Keywords: Endemism, genetic diversity, isoenzyme, kniphofia, inbreeding coefficient

Abstract

There are seven species of genus Kniphofia in Ethiopian flora. K. foliosa, K. hildebrandtii, K. insignis, K. isoetifolia, and K. schimperiare endemic. Kniphofia pumila and K. thomsonii are widespread from West Africa to Eastern and Central Africa. In this study the genetic diversity and the relationships between five endemic and one widespread Kniphofia species in Ethiopia was conducted based on isoenzymes systems. The electrophoretic analyses of four enzymes systems in the species from ten experimental sites in ten locations revealed seven putative loci, of which PGM-1, PGM-2, AAT-2 and GPI-2 were polymorphic. The species have displayed higher genetic diversity parameters than other endemic plants. The over all mean inbreeding coefficient (F) was positive indicating slight deficiency in the number of heterozygotes. The total genetic diversity varies from 0.5 in K. schimperito 1.11 in K. isoetifolia indicating very low diversification between the populations with in a species. At the generic level HT ranges from 0.034 to 0.470 with a mean of 0.247. The genetic variation among the species (GST) is 6.6%. Over all mean of genetic distance (0.011) and genetic similarity (0.938) indicated high similarity among the populations. Despite morphological variation particularly in floral morphology and inflorescence architecture, the over all mean of unbiased genetic identity of the species (0.989) is much higher than described for congeneric species (I = 0.64). The results, therefore, indicate that the Ethiopian Kniphofia species share a fairly recent common ancestor, but have differentiated in floral and inflorescence character through rapid evolution. This hypothesis needs, however, further testing.

Key words/phrases: Endemism, genetic diversity, isoenzyme, kniphofia, inbreeding coefficient

SINET: Ethiopian Journal of Science Vol. 27 (2) 2004:143–152
Published
2005-10-18
Section
Articles

Journal Identifiers


eISSN: 2520-7997
print ISSN: 0379-2897