Morphological diversity among accessions of Pelargonium sidoides DC. in the Eastern Cape, South Africa

Abstract

Pelargonium sidoides is an indigenous medicinal plant of South Africa harvested for local use and international trade. Due to its high economic and medicinal importance, the rate and the number of its harvesters have increased in recent years. This has led to a drastic drop in the population of the species in the wild. In order to develop breeding and propagation program for this species, a baseline study was conducted to determine the morphological variability exhibited by 30 accessions of P. sidoides collected from three locations within the Eastern Cape. A list of descriptors developed by PGRI/IITA/BAMNET for Bambara groundnut was adopted and a total of 16 traits (2 qualitative and 14 quantitative) were determined during the vegetative and reproductive stages. Data were subjected to univariate and multivariate statistical analyses. Ample variability was found for most traits measured. Cluster analysis showed unique clustering of accessions forming 29 morphotypes (clusters) out of the 30 accessions studied. At the core level, plant materials collected from the same location were found to cluster in pair of accessions thus implying similarity of adaptation. The reproductive characters which include number of flowers per inflorescence, length and width of inflorescence and number of inflorescence per vine showed the highest variation among the quantitative characters measured. The importance of this work on the propagation and conservation of Pelargonium sidoides is discussed.