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Numerical taxonomy on varieties of Adansonia digitata L.
Abstracts
181
b
South African National Biodiversity Institute, Private Bag X101, Pretoria 0001, South Africa
A phylogenetic and taxonomic analysis of Curio P.V.Heath (Asteraceae)
Genus Caesalpinia L. belongs to the tribe Caesalpiniaceae Benth. in the Fabaceae family, subfamily Caesalpinioideae. The subfamily includes approximately 2250 species in 171 genera distributed in tropics and subtropical regions in Southeast Asia, Africa and South America. The genus in its broadest sense comprises of about 140 species distributed throughout the tropics and pantropical regions. Within Caesalpiniasens str. about eleven are found in Africa excluding exotics (one endemic in Congo, six restricted to southern Africa, four restricted to the East and North East Africa, with one extending to Oman, South Yemen and Arabia). Caesalpiniasens str. is a genus with great morphological variation from trees, shrubs and perennial herbs. However the southern African species described here ranges from shrubs to trees. The aim of this paper is to revise and update the nomenclature, taxonomy and geographical distribution of the species occurring in southern Africa including non-indigenous species. In southern Africa ten species are recognized of which six species are restricted to the region (three of the six are endemic to Namibia); four are non-indigenous species (of which two species are classified as invasive to South Africa).
M. Jackson, L. Joubert Department of Plant Sciences, University of the Free State, PO Box 339, Bloemfontein 9300, South Africa
doi:10.1016/j.sajb.2015.03.051
Numerical taxonomy on varieties of Adansonia digitata L. J.A. Jacob, D.A. Zhigila Botany Programme, Department of Biological Sciences, Gombe State University, Gombe, Gombe State, Nigeria Variations in the morphological features of Adansonia digitata L. were studied, which may be used for the delimitation of varieties in the species. The wide range of uses of these naturalised trees in the world have in recent time witnessed increasing demand of their foliar, bark, root, fruit and seed products in nutritional, fibre and medical applications. The upsurge demand for these products needs to be balanced with new varieties of improved performance to meet the supply chain. To achieve this, the present study was aimed at setting the foundation of variability analysis based on morphological features to detect promising varieties for mapping out of future breeding schemes of this multi-purpose tree. The fresh specimens were collected in open vegetation, plantations, houses and bushy areas from mature plant stands in Sudan and Guinea savannah of Nigeria. Both qualitative and quantitative characters studied, coded and subjected to cluster analysis. Some morphological characters indicated close affinity amongst the varieties of Adansonia digitata. Features of taxonomic importance amongst the varieties of A. digitata include leaf surface, pod surface, leaf stalk surface, pod surface, pod end form, pod colour, pod size, stalk size, number of seed per pod, leaf size, seed size, occurrence of leaflet number and leaflet size. Within the species, there is evidence indicating the existence of a number of local types differing in habit, vigour, size, and quality of the fruits and vitamin content. These features were considered to be taxonomically relevant in the delimitation of these varieties. Numerical analysis of the qualitative and quantitative characters data using cluster analysis — average linkage, single linkage, complete linkage and centroid methods delimits all the Operational Taxonomic Units (OTUs) into four varieties hence, infraspecific classification of A. digitata is hereby proposed.
doi:10.1016/j.sajb.2015.03.052
Despite the large volume of literature that is available on the systematics of the tribes within the Asteraceae, a lack of knowledge still exists for the intra- and intergeneric relationships in tribes such as Senecioneae. A phylogeny for Senecioneae with a delimitation for the genus Senecio L., showed that the Gynoroid clade which contains some representatives of the segregate genus Curio P.V.Heath was unresolved. A total of 22 species names have been published in Curio. Subsequently several of these species have been removed to Senecio L. or other allied genera such as Kleinia Mill. while several names have been synonymised with other Curio species. Consequently the circumscription and taxonomic status of the genus is poorly understood, necessitating a systematic revision of the genus. Curio species were collected from around South Africa and live specimens are currently kept in greenhouse conditions. A phylogenetic analysis of 16 species based on DNA sequence data from nuclear ITS and chloroplast trnT–trnF regions using parsimony and Bayesian inference analyses resulted in the first molecular phylogeny for the genus Curio. A well resolved phylogeny with good support values was obtained showing Curio to be monophyletic. Two prominent clades were identified and some of the sprawling species cluster together forming a polytomy. The distribution, habitat, morphology and micromorphology of available species are investigated using this phylogeny and possible evolutionary factors affecting speciation in the genus are discussed.
doi:10.1016/j.sajb.2015.03.053
Taxonomy of the Cotula turbinata group (Asteraceae, Anthemideae) A. Jakoet, A.R. Magee Compton Herbarium, South African National Biodiversity Institute, Private Bag X7, Claremont 7735, South Africa Cotula is a large and poorly studied genus of about 55 species. The genus is centred in southern Africa, with species also in Australia, the Southern Oceanic Islands as well as Central and South America. The urgent need for a taxonomic treatment of Cotula has long been acknowledged, with no formal revision available. To this end, a taxonomic revision of the Cotula turbinata group is presented here. The species in this group have previously been treated as a separate genus, Cenia, based on the apically swollen peduncles. At the beginning of this study eight species were recognised, four in the Greater Cape Region and another four in the summer rainfall KwaZulu Natal and Eastern Cape. Extensive herbarium and field studies have revealed the presence of an additional three species of which one is described as new. As a result, 11 species are here recognised, distinguished by their habit, leaf dissection, floret colour, presence or absence of ray-like disc florets and cypsela morphology. Within the group the species can be divided into two subgroups based on the shape of the involucral bracts and the presence or absence of unique ray-like florets.
doi:10.1016/j.sajb.2015.03.054
181
b
South African National Biodiversity Institute, Private Bag X101, Pretoria 0001, South Africa
A phylogenetic and taxonomic analysis of Curio P.V.Heath (Asteraceae)
Genus Caesalpinia L. belongs to the tribe Caesalpiniaceae Benth. in the Fabaceae family, subfamily Caesalpinioideae. The subfamily includes approximately 2250 species in 171 genera distributed in tropics and subtropical regions in Southeast Asia, Africa and South America. The genus in its broadest sense comprises of about 140 species distributed throughout the tropics and pantropical regions. Within Caesalpiniasens str. about eleven are found in Africa excluding exotics (one endemic in Congo, six restricted to southern Africa, four restricted to the East and North East Africa, with one extending to Oman, South Yemen and Arabia). Caesalpiniasens str. is a genus with great morphological variation from trees, shrubs and perennial herbs. However the southern African species described here ranges from shrubs to trees. The aim of this paper is to revise and update the nomenclature, taxonomy and geographical distribution of the species occurring in southern Africa including non-indigenous species. In southern Africa ten species are recognized of which six species are restricted to the region (three of the six are endemic to Namibia); four are non-indigenous species (of which two species are classified as invasive to South Africa).
M. Jackson, L. Joubert Department of Plant Sciences, University of the Free State, PO Box 339, Bloemfontein 9300, South Africa
doi:10.1016/j.sajb.2015.03.051
Numerical taxonomy on varieties of Adansonia digitata L. J.A. Jacob, D.A. Zhigila Botany Programme, Department of Biological Sciences, Gombe State University, Gombe, Gombe State, Nigeria Variations in the morphological features of Adansonia digitata L. were studied, which may be used for the delimitation of varieties in the species. The wide range of uses of these naturalised trees in the world have in recent time witnessed increasing demand of their foliar, bark, root, fruit and seed products in nutritional, fibre and medical applications. The upsurge demand for these products needs to be balanced with new varieties of improved performance to meet the supply chain. To achieve this, the present study was aimed at setting the foundation of variability analysis based on morphological features to detect promising varieties for mapping out of future breeding schemes of this multi-purpose tree. The fresh specimens were collected in open vegetation, plantations, houses and bushy areas from mature plant stands in Sudan and Guinea savannah of Nigeria. Both qualitative and quantitative characters studied, coded and subjected to cluster analysis. Some morphological characters indicated close affinity amongst the varieties of Adansonia digitata. Features of taxonomic importance amongst the varieties of A. digitata include leaf surface, pod surface, leaf stalk surface, pod surface, pod end form, pod colour, pod size, stalk size, number of seed per pod, leaf size, seed size, occurrence of leaflet number and leaflet size. Within the species, there is evidence indicating the existence of a number of local types differing in habit, vigour, size, and quality of the fruits and vitamin content. These features were considered to be taxonomically relevant in the delimitation of these varieties. Numerical analysis of the qualitative and quantitative characters data using cluster analysis — average linkage, single linkage, complete linkage and centroid methods delimits all the Operational Taxonomic Units (OTUs) into four varieties hence, infraspecific classification of A. digitata is hereby proposed.
doi:10.1016/j.sajb.2015.03.052
Despite the large volume of literature that is available on the systematics of the tribes within the Asteraceae, a lack of knowledge still exists for the intra- and intergeneric relationships in tribes such as Senecioneae. A phylogeny for Senecioneae with a delimitation for the genus Senecio L., showed that the Gynoroid clade which contains some representatives of the segregate genus Curio P.V.Heath was unresolved. A total of 22 species names have been published in Curio. Subsequently several of these species have been removed to Senecio L. or other allied genera such as Kleinia Mill. while several names have been synonymised with other Curio species. Consequently the circumscription and taxonomic status of the genus is poorly understood, necessitating a systematic revision of the genus. Curio species were collected from around South Africa and live specimens are currently kept in greenhouse conditions. A phylogenetic analysis of 16 species based on DNA sequence data from nuclear ITS and chloroplast trnT–trnF regions using parsimony and Bayesian inference analyses resulted in the first molecular phylogeny for the genus Curio. A well resolved phylogeny with good support values was obtained showing Curio to be monophyletic. Two prominent clades were identified and some of the sprawling species cluster together forming a polytomy. The distribution, habitat, morphology and micromorphology of available species are investigated using this phylogeny and possible evolutionary factors affecting speciation in the genus are discussed.
doi:10.1016/j.sajb.2015.03.053
Taxonomy of the Cotula turbinata group (Asteraceae, Anthemideae) A. Jakoet, A.R. Magee Compton Herbarium, South African National Biodiversity Institute, Private Bag X7, Claremont 7735, South Africa Cotula is a large and poorly studied genus of about 55 species. The genus is centred in southern Africa, with species also in Australia, the Southern Oceanic Islands as well as Central and South America. The urgent need for a taxonomic treatment of Cotula has long been acknowledged, with no formal revision available. To this end, a taxonomic revision of the Cotula turbinata group is presented here. The species in this group have previously been treated as a separate genus, Cenia, based on the apically swollen peduncles. At the beginning of this study eight species were recognised, four in the Greater Cape Region and another four in the summer rainfall KwaZulu Natal and Eastern Cape. Extensive herbarium and field studies have revealed the presence of an additional three species of which one is described as new. As a result, 11 species are here recognised, distinguished by their habit, leaf dissection, floret colour, presence or absence of ray-like disc florets and cypsela morphology. Within the group the species can be divided into two subgroups based on the shape of the involucral bracts and the presence or absence of unique ray-like florets.
doi:10.1016/j.sajb.2015.03.054