Thesis (M.Sc. (Microbiology)) -- University of Limpopo, 2010 / A 29 kDa lectin that shows specificity for galactose was isolated from Lonchocarpus capassa seeds by a combination of ammonium sulphate precipitation and affinity chromatography on a galactose-sepharose column. The 29 kDa lectin subunit co-purified with a 45 kDa subunit. The N-terminal sequence of the 29 kDa subunit showed homology to other legume lectins while that of 45 kDa subunit was capped. A 360 bp fragment was amplified using degenerate primers designed from internal protein sequences of the 29 kDa subunit and a 5´ RACE system primer. The cDNA fragment was cloned into pTz57R/Tvector and transformed into E. coli. The partial amino acid sequence of the lectin subunit was deduced from the nucleotide sequence of the clone. The 360 bp fragment consisted of 342 bp sequence coding for the start codon, leader sequence, N-Terminal sequence and sequences of the 79 amino acids from N-terminus. Comparison of the deduced amino acid sequence with other legume lectins showed regions of sequence homology with precursor sequences of Robinia pseudoacacia Bark lectin, a non seed lectin from Pisum sativum (pea), and the galactose specific peanut agglutinin (PNA) from Arachis hypogaea. Alignment of these sequences showed conserved regions including the metal binding sites found in all legume lectins. The 5´ end DNA sequence was used to design locus-specific primers which were used with genome walking cassette primers in an attempt to amplify the full L. capassa lectin gene. The cassette primers were designed from restriction enzyme sites on the cassette. Of all the restriction enzymes on the cassette Hind III and the L. capassa gene-specific primers amplified 288 bp of the 342 bp sequence already obtained from sequencing of the cDNA sequence with minor amino acid differences. Although the full lectin sequence was not obtained the study confirmed the presence of a galactose-specific lectin in L. capassa seeds.

No description available.

With the high rate of human population growth in Africa, it is imperative that food production be increased through improving yields and bringing more land under cultivation. Nitrogen is a key element required for plant growth and with the low input of fertilizers into African farming-systems, it is necessary to harness biological nitrogen fixation (BNF) to its fullest extent. To maximize nitrogen fixation in crop and pasture legumes under various conditions and cropping systems requires intensified research. In this study the diversity of root nodule bacteria associated with Lotononis species in South Africa was investigated. To our knowledge, no past attempts have been made to investigate the diversity of rootnodule-bacteria associated with the genus Lotonollis. Eighty nodulated plants representing thirty-two Lotononis spp. were collected from all the main geographical and climatological regions in South Africa. Isolates obtained from rootnodules were purified and characterized with sodium dodecyl-sulphate gel polyacrylamide gel electrophoresis (SDS-PAGE), supplemented at the genomic level with 16S rDNA sequence data of selected strains. Initial screening (SDS-PAGE) showed that most isolates obtained from the same plant species, grouped into various clusters within the dendrogram. A few of the isolates from similar host plants seemed to cluster with high similarity. It is thus reasonable to conclude that host specificity in the symbiotic interaction is less applicable for most species of Lotononis. When considering the geographical origins of the isolates, their diverse nature was clearly illustrated. It was showed that isolates from similar geographical regions were evenly distributed throughout the dendrogram. Some of the isolates obtained from arid environments formed closely related electrophoretic groups. It was subsequently shown that root-nodule bacteria associated with Lotononis species are not restricted to a particular rhizobial genus, but that heterogeneity is evident. Some of the isolates were also related to genera outside the Rhizobiaceae, namely Methylobacterium and Burkholderia. / Dissertation (MSc (Microbiology))--University of Pretoria, 2006. / Microbiology and Plant Pathology / unrestricted

This work is an account of investigations into the chemistry of one of the members of the Amaryllidacae family, Ammocharis coranica, and one of the members of the Fabaceae family, Sophora velutina. Chapter one is an account of the extractives from the bulbs of Ammocharis coranica. In all, twelve compounds, eight alkaloids and four cycloartane compounds have been isolated of which one alkaloid and one cycloartane compound have not been described previously. Plants belonging to the Amaryllidacae family have been used by traditional healers, especially in Africa, to treat a range of illnesses and diseases. The alkaloids isolated from these plants have been shown to exhibit responses to muscle stimulant, antiviral, antifungal, antiyeast, antimalarial, cytotoxic and antitumoural activities. Ammocharis coranica is used by the Zulu tribe in South Africa to treat any illness believed to be caused by witchcraft. Alkaloids from the three most common types among the isoquinoline group were found in this species. These are lycorine, 1-O-acetyllycorine, hippadine, acetylcaranine, and the novel 1-O- acetyl-9-norpluviine from the lycorine type, 6-α-hydroxypowelline from the crinine type and hamayne and crinamine from the haemanthamine type. Cycloartane compounds have not been reported previously from the Amaryllidaceae family. All four cycloartane compounds had a common side chain, containing an olefinic methylene group at position 24, but differed in their substituents at positions 3 and 4. These compounds were found to be 24-methylenecycloartan-3β-ol, cycloeucalenol, cycloeucalenone and the novel compound 4-methylenepollinastanone. Chapter two is an account of the extractives from the seeds of Sophora velutina. The seeds of other Sophora species have been used in traditional ceremonies by the Indians of the Southwest United States and adjacent Mexico because of their hallucinogenic activity. The seeds of Sophora velutina subsp. zimbabweensis found in Zimbabwe are suspected to have historically been used by the natives for their hallucinogenic properties. These plants have been known to contain several quinolizidine alkaloids, flavonoids and isoflavonoids. One alkaloid, N-methylcytisine and two isoflavones, pseudobaptigenin and calycosin, as well as the common phytosterol, β-sitosterol were isolated from the seeds of this species. N-methylcytisine is a common quinolizidine alkaloid, isolated previously from several Sophora species and pseudobaptigenin and calycosin are well known isoflavones, isolated previously from several species in the Fabaceae. / Thesis (M.Sc.)-University of Natal, Durban, 1999.

M.Sc. (Botany) / The genus Lessertia DC. consists of 54 species of papilionoid legumes. The species have imparipinnate leaves, paired stipules, sub-capitate or elongate racemes and compressed or inflated legumes. The closest relative of the genus is Sutherlandia R. Br. ex W. T.Aiton, which differs in having a very large, bird-pollinated flower, a standard which is smaller than the keel, a long ovary stipe and a very large, much inflated legume. The last comprehensive revision of Lessertia was done by Harvey (1862), where 30 species were recognized. Harvey concluded that the species were difficult to define. This study was therefore initiated to evaluate characters of possible taxonomic value so that the circumscription and identification of species can be facilitated. More than 1000 specimens from different herbaria were examined to study morphological characters such as habit, indumentum, leaves and leaflets, flowers and flowering times, fruits, habitat and distribution of the species. Flowers of all the species were dissected and flower parts were drawn using camera lucida. Flower characters such as the length, width and vestiture of the petals were studied. For flavonoids and terpenoids, 17 species of Lessertia were sampled for a pilot study to compare chemical compounds between the species. The ethnobotanical literature was reviewed in order to compile a list of all the species of value in traditional medicine. Vegetative characters are often not species-specific but they can be used to distinguish between some closely related species, either as single characters or as combinations of characters. Further details can be seen in the keys presented in this study.

Thesis (M.A. Agricultural Management (Crop Science)) -- University of Limpopo, 2016 / Guar bean (Cyamopsis tetragonoloba L. Taub) is a drought tolerant leguminous crop usually grown for its seed which has a special gum (galactomannan) used in the food and the mining industries. The study aimed at evaluation of yield potential and agronomic management of 14 determinate and indeterminate guar accession lines sourced from the Australian Tropical Crops and Forages collection grown under dry-land conditions of Limpopo province and assessing their response to phosphorus and inoculation. Two different experiments, one on variety evaluation and the other on response to P fertilizer and inoculation were conducted during 2006/7 and 2007/8 growing seasons at Syferkuil and Tompi Seleka in the Limpopo Province, South Africa. There were significant differences amongst the 14 guar accession lines at Syferkuil during 2006/7 and 2007/8 and Tompi Seleka during 2007/8 growing seasons. Tompi Seleka showed higher potential for guar bean production over Syferkuil on the basis of grain yield. Seed yield from the two locations during the two seasons ranged from 326 kg ha-1 by variety Stonewall to 2340 kg ha-1 by variety Durgapurasaffed. At Syferkuil in 2006/7 Brooks variety recorded the highest seed yield of 1103 kg ha-1 while Hall achieved lowest seed yield of 353 kg ha-1. During 2007/8 at Syferkuil, TRCF 95203 recorded the highest seed yield of 701 kg ha-1 and Stonewall recorded lowest of 326 kg ha-1. At Tompi Seleka in the same season, the highest yield was recorded with Durgpurasaffed variety that recorded 2340 kg ha-1 and lowest Stonewall with 720 kg ha-1. The varieties which consistently performed well and were within the top five performing lines at the two locations were Durgapurasaffed, TRCF CSIRO and Brooks. The accession lines at Tompi Seleka experiment gave higher dry matter and seed yields than at Syferkuil, suggesting their preference for hot environments. In the second experiment, the response of two guar bean varieties to phosphorus level and inoculation was evaluated. Variety did not influence seed yield. Application of phosphorus (P) at 60 kg ha-1 plus inoculation significantly increased seed yield. At Tompi Seleka 2007/8 season, 60 kg ha-1 of P application achieved seed yield 37% higher than the control treatment. In the same season at Syferkuil the highest seed yield was also recorded at 60 kg ha-1 P application and was 57% xiii more than lowest seed yield from the control treatment. Grain yield significantly increased during 2006/7 as influenced by P application rate of 30 kg ha-1 compared to zero P fertilizer while there was no significant different between P rates during 2007/8 season at this site. The results from the study showed good response P application in the range of 30 to 60 kg ha-1. Inoculation significantly increased seed and dry matter yield at all sites. Variety X P levels and variety X inoculation interactions significantly influenced seed yield and dry matter at all sites. Both varieties achieved the highest seed yield at 60 kg ha-1 and the lowest was with the control at Syferkuil for both varieties. At Tompi Seleka, the control and application 30 kg ha-1 of fertilizer gave similar seed yield for both varieties. At Syferkuil in 2006/7 and Tompi Seleka in 2007/8 both Stonewall and Cedric were higher with inoculation but in 2007/8 Cedric had lower seed yield with inoculation at Syferkuil. The Phosphorus X inoculation interaction was significant with combination of 60 kg P ha-1 and inoculation giving significantly higher seed yield than the 0 kg P ha-1 and no inoculation. Future experiments should consider inclusion test in these guar accession under dryland conditions, levels of P higher than 60 kg P ha-1, include nodulation data, quality evaluation of guar seed and conducting basic growth margin analysis on P and inoculation of guar. / ACIAR Project

Thesis (M.Sc. (Agricultural Management)) --University of Limpopo, 2004 / Identification of annual grass/legume intercropping or mixtures with superior nutrient traits and Dry matter (DM) production is critical to increasing productivity of the crop and animal production among small-scale farmers in the Limpopo Province. Three similar field experiments were established at different locations in the Province to determine the significance of the contribution of annual summer legumes, and cutting treatments on the nutritive value and dry matter accumulation of the popular forage sorghum (Sorghum spp) and pearl millet (Pennisetum glaucum) intercropped with cowpea (Vigna unguiculata) and dolichos (Lablab purpureus). The cropping systems evaluated were sole sorghum, sole pearl millet, sorghum + cowpea, sorghum + dolichos, pearl millet + cowpea and pearl millet + dolichos. The treatments sole sorghum and pearl millet significantly (P<0.05) outperformed the other treatments in terms of DM production at most cutting stages. The remaining four treatments though, inferior in DM in this study, yielded better than the average yield on farmers' fields in the Province. Higher protein content was obtained in mixtures than in sole cropping, and generally there was lower protein production and content at matured stages (CT3) in the study. The other chemical composition analyzed in the study was not significant for both mixtures and sole cultures.

MSCAGR (Plant Production) / Department of Plant Production / See the attached abstract below

MSc (Plant Production) / Department of Plant Production / See the attached abstract below

MSCAGR (Plant Production) / Department of Plant Production / Bambara groundnut (Vigna subterranea) is one of the most important legumes cultivated primarily for food by smallholder farmers in Africa. It is an affordable source of protein and contributes to income generation as well as soil fertility. Despite its importance, it is cultivated largely for subsistence purposes in South Africa. Growers use landraces. The agronomic performance of the traditional varieties depends on environmental factors prevailing in a particular area. In Limpopo and Mpumalanga Provinces, there is no adequate information regarding the performance of bambara groundnut germplasm. The objectives of the study were to (i) determine the agronomic performance of Bambara groundnut across three contrasting locations in Limpopo and Mpumalanga provinces over two cropping seasons (ii) determine the genotypic variation in the seed protein level among 42 bambara groundnut genotypes. Forty-two bambara groundnut genotypes were evaluated under three different environmental conditions (Syferkuil, Thohoyandou and Nelspruit) over two (2013/2014, 2014/2015) seasons in a 7 × 6 rectangular lattice design replicated three times. Eight agronomic traits including dry shoot weight (DSW), number of pods per plant (NPP), pod length (PL), number of seed per pod (NSP), pod weight per plant (PWT), seed weight per plant (SWT), 100 seed weight (100-SWT) and seed yield (SYLD) were measured. The results showed that there were significant genotype x location interactions which demonstrated that the prevailing agro-ecological conditions at the test locations were distinct from each other. Five genotypes (‘BGN-19‘, ‘BGN-11‘, ‘BGN-12‘, ‘BGN-4‘and ‘BGN-34‘) attained >25.0% seed yield advantage over the local check ‘BGN-39‘. The results also showed that light brown coloured genotypes attained relatively higher seed yield compared to the other seed colours types. The cultivar superiority index (CSI) showed that three genotypes (‘BGN-12‘, ‘BGN-19’ and ‘BGN-34’) were the most stable across the test locations and attained >900.0 kg/ha on average. There were significantly high positive correlations between PWT and each of the three other attributes (SWT, 100 SWT and SYLD). In terms of seed protein, the results showed a poor relationship between seed yield and protein levels. ‘BGN-12’ which produced the highest seed yield, attained the lowest percent seed protein while genotype. On average, the genotypes contained 21.72% protein. The highest and lowest seed protein quantities were attained by the genotypes ‘BGN-42’ (25.17%) and ‘BGN-12’ (19.89%) respectively. / NRF