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Item Co-cultivation and matching of early- and late-maturing pearl millet varieties to sowing windows can enhance climate change adaptation in semi-arid sub-Saharan agroecosystems(MDPI Open access journal, 2023) Awala, Simon Kamwele; Hove, Kudakwashe; Valombola, Johanna Shekupe; Nafuka, Helena Nalitende; Simasiku, Evans Kamwi; Chataika, Barthlomew; Horn, Lydia Ndinelao; Angombe, Simon; Akundabweni, Levi S.M; Mwandemele, OsmundIn semi-arid regions, climate change has affected crop growing season length and sowing time, potentially causing low yield of the rainfed staple crop pearl millet (Pennisetum glaucum L.) and food insecurity among smallholder farmers. In this study, we used 1994–2023 rainfall data from Namibia's semi-arid NorthCentral Region (NCR), receiving November–April summer rainfall, to analyze rainfall patterns and trends and their implications on the growing season to propose climate adaptation options for the region. The results revealed high annual and monthly rainfall variabilities, with nonsignificant negative trends for November– February rainfalls, implying a shortening growing season. Furthermore, we determined the effects of sowing date on grain yields of the early-maturing Okashana-2 and local landrace Kantana pearl millet varieties and the optimal sowing window for the region, using data from a two-year split-plot field experiment conducted at the University of Namibia-Ogongo Campus, NCR, during the rainy season. Cubic polynomial regression models were applied to grain yield data sets to predict grain production for any sowing date between January and March. Both varieties produced the highest grain yields under January sowings, with Kantana exhibiting a higher yield potential than Okashana-2. Kantana, sown by 14 January, had a yield advantage of up to 36.0% over Okashana-2, but its yield gradually reduced with delays in sowing. Okashana-2 exhibited higher yield stability across January sowings, surpassing Kantana’s yields by up to 9.4% following the 14 January sowing. We determined the pearl millet optimal sowing window for the NCR from 1–7 and 1–21 January for Kantana and Okashana-2, respectively. These results suggest that co-cultivation of early and late pearl millet varieties and growing early-maturing varieties under delayed seasons could stabilize grain production in northern Namibia and enhance farmers' climate adaptation. Semi-arid agro-region policymakers could utilize this information to adjust local seed systems and extension strategies.Item Comparative cytological and transcriptome analyses of ny2 mutant delayed degeneration of tapetal cells and promotes abnormal microspore development in neo-tetraploid rice(Frontiers, 2023) Kamara, Nabieu; Jiao, Yamin; Huang, Weicong; Cao, Lichong; Zhu, Lianjun; Zhao, Chongchong; Huang, Xu; Shivute, Fimanekeni N.; Liu, Xiangdong; Wu, Jinwen; Shahid, Muhammad QasimWe aimed to investigate the genetic defects related to pollen development and infertility in NY2, a novel tetraploid rice germplasm known as Neo-tetraploid rice. This rice variety was created through the crossbreeding and selective breeding of various autotetraploid rice lines and has previously shown high fertility. Our previous research has revealed that the NY2 gene, encoding a eukaryotic translation initiation factor 3 subunit E, regulates pollen fertility. However, the underlying mechanism behind this fertility is yet to be understood. To shed light on this matter, we performed a combined cytological and transcriptome analysis of the NY2 gene. Cytological analysis indicated that ny2 underwent abnormal tapetal cells, microspore, and middle layer development, which led to pollen abortion and ultimately to male sterility. Genetic analysis revealed that the F1 plants showed normal fertility and an obvious advantage for seed setting compared to ny2. Global gene expression analysis in ny2 revealed a total of 7545 genes were detected at the meiosis stage, and 3925 and 3620 displayed upregulation and downregulation, respectively. The genes were significantly enriched for the gene ontology (GO) term “carbohydrate metabolic process. Moreover, 9 genes related to tapetum or pollen fertility showed downregulation, such as OsABCG26 (ATP Binding Cassette G26), TMS9-1 (Thermosensitive Male Sterility), EAT1 (Programmed cell death regulatory), KIN14M (Kinesin Motor), OsMT1a (Metallothionein), and OsSTRL2 (Atypical strictosidine synthase), which were validated by qRT-PCR. Further analyses ofDEGs identified nine down-regulated transcription factor genes related to pollen development. NY2 is an important regulator of the development of tapetum and microspore. The regulatory gene network described in this study may offer important understandings into the molecular processes that underlie fertility control in tetraploid rice.Item Comparative study on oyster mushroom grown on composited substrate:The effect on yield, growing period and fruiting body size(Journal of Advances in Biotechnology, 2022) Shivute, FimanekeniCultivation of the oyster mushroom on horse manure and wheat straw compost without nutrient supplementation was investigated. The growing, yield and fruiting body size effects on open trays and substrate bags were determined. Incubation and fruiting period on trays and inoculated bags were compared. The bagged compost yielded higher mushroom growth rate and yield than the tray compost. The fruiting bodies of the mushroom on trays were smaller, pile and thinner as compared to the mushrooms on the bags, which were bigger, fresh and strong. However, it was found that when oyster mushroom are grown on trays, the yield decrease, there is less moisture in the tray and substrate is exposed to heat, the pin head dries as they develop and those that succeed to grown further will grow as thin with a little head due to lack of oxygen. Comparing compost in bags with compost substrate in trays, bags yielded about 20% more mushrooms than tray sunder the same cultivation conditions. Conversely, the incubation period of compost in bags took longer, as compared to the incubation of compost in trays. Trays gave their first flash 10% earlier than the bags.Item Prospects of rhizobial inoculant technology on Bambara groundnut crop production and growth(Frontiers, 2022) Fwanyanga, FelicitasAfter peanuts and cowpeas (Vigna unguiculata), the Bambara groundnut (Vigna subterranea (L.) Verdc) is the third most significant food legume in Africa. It is characteristically grown in marginal soils, is drought tolerant, and also has the potential for nitrogen fixation. Despite that, year-on-year Bambara groundnut yields are on a gradual decline due to a combination of abiotic and biotic stresses such as uneven annual rainfall and climate-induced changes in soil microbial community compositions, negatively impacting food security. Thus, the application of rhizobial inoculants at planting significantly improves yields in many leguminous crops. Moreover, symbiotic inoculants are well established in developed countries for improving nitrogen fixation and productivity in grain legumes. Sub-Saharan African countries, however, still under-utilise the above practice. In crop production, nitrogen (N) is the most frequently deficient nutrient since it stimulates root and shoots growth. Whereas nitrogen fertilisers can be used to supplement soil N levels, they are, however, also costly, at times inadequate, may not be timely in supply and may have deleterious environmental consequences. Hence, rhizobial inoculants are seen as a cheaper, easier, and safer method for improving N-fixation and crop productivity in grain legumes, as a result, smallholder farming systems are food secure. Thus, identifying the most efficient rhizobial strains for biofertiliser production for Bambara groundnut is of utmost importance to the farming communities.Item Cowpea production challenges and contribution to livelihood in Sub-Sahara region(Scientific Research Publishing, 2022) Horn, Lydia; Nghituwamata, Selma N; Ueitele, IsabellaAbstract Cowpea [Vigna unguiculata (L.) Walp.] is an important grain legume mainly grown in tropical and subtropical regions for vegetables, grains, and fodder. The crop is grown predominantly in the dry savannahs to the Sahel in the fringes of the Sahara Desert where the annual rainfall is around 300 mm or less. Cowpea provides shelter as a cover crop and improves soil fertility by fixing atmospheric nitrogen. Its grain is preferred for high levels of protein, energy, micro-and macronutrients. Cowpea belongs to the family Fabaceae and sub-family Faboidea, and it is a self-pollinating crop with low and narrow genetic diversity, making it susceptible to various environmental factors. Various research projects have been established on cowpea, and as a result, various cowpea germplasm is stored at Africa International Institute of Tropical Agriculture (IITA)—Nigeria, the USDA repository in Griffin, GA (USA), the University of California, Riverside, CA (USA), and at the National Bureau of Plant Genetic Resources (NBPGR) in New Delhi, India. Despite the availa- ble germplasms, cowpea productivity remains very low in many countries due to a wide array of abiotic and biotic stresses and socio-economic constraints. This review summarizes some aspects of cowpea, including origin and history, challenges, economic importance, and constraints to production, providing possible useful information for cowpea researchers, agronomists, and producers in SSA.Item Utilization of plant genetic resources of Bambara groundnut conserved ex situ and genetic diversification of its primary genepool for semi-arid production(MDPI, 2022) Pasipanodya, Josephine TBambara groundnut (Vigna subterranea (L.) Verdc) is a nutritious and drought-tolerant crop that is native to Africa. Currently, it possesses a cosmopolitan distribution across the semi-arid agro-ecologies of Africa and its cultivation has extended to other regions, particularly in the drier parts of Asia and Indonesia. Due to historic neglect, research on the crop and policy prioritization in national breeding programs is lagging; hence, varietal development is in its infancy. Farmers rely on traditional landraces, which are characterized by low productivity and yield. Breeding for moisture stress adaptation and high yield is crucial to improve its productivity and adequate genetic diversity is desired to strengthen resiliency for climate adaptation and nutritional and food security. Nevertheless, thousands of plant genetic resources (PGRs) conserved in several gene banks are still not being fully utilized to reintroduce lost diversity into farmers’ fields and pre-breeding activities. The exploitation of ex situ conserved PGRs has been minimal due to a lack of extensive genetic characterization. Thus, to harness utilization of the PGRs in genetic improvement programs, holistic strategies including the traditional genomic resources and participatory-led trait discoveries are needed to bridge the gap between conservation and utilization of ex situ germplasm. This review focuses on the PGRs of bambara, methods to widen genetic diversity, genomic resources, and highthroughput phenotyping to enhance the utilization of genetic resources in pre-breeding programs, and approaches to identify useful adaptive features for yield and drought.Item Towards medicinal tea from untapped Namibian Ganoderma: Phenolics and in vitro antioxidant activity of wild and cultivated mushrooms(South African Journal of Science, 2022) Hamenye, Karlin, K NGanoderma is a genus of mushrooms that is prized in developed nations, especially those in Asia, due to its health-promoting properties, which are attributed to bioactive compounds such as phenolics. However, in developing countries, particularly in Africa, Ganoderma mushrooms are untapped and are barely identified. In this study, we identified Ganoderma species collected from different host trees in the wild in Namibia, cultivated them on one substrate and determined their water absorption and solubility indices. Total phenolics (TP), total flavonoids (TF), condensed tannins (CT) and in vitro antioxidant activity (AA) were determined in hot water infusions made from wild and cultivated Ganoderma mushrooms. Folin–Ciocalteu, aluminium chloride, vanillin-HCl, and DPPH assay methods were used to determine TP, TF, CT and AA, respectively. Wild species had 6.12–11.70% moisture, 1.91–5.32% ash, 11.55–24.40 (g of absorbed water/g of dry sample) water absorption index, 3.60–24.10% water solubility index, 18.37–44.78 (mg GAE/g of sample) TP, 0.09–1.67 (mg QE/g of sample) TF, 2.97–6.37 (mg CAE/g of sample) CT and 40.8–49.3% AA. Cultivated species had 9.64 13.45% moisture, 2.34–6.20% ash, 13.55–28.30 water absorption index, 6.40–25.35% water solubility index, 36.70–52.73 (mg GAE/g of sample) TP, 0.41–0.86 (mg QE/g of sample) TF, 11.38–15.29 (mg CAE/g of sample) CT and 53.6–63.7% AA. Infusions prepared from cultivated Ganoderma species had higher levels of TP, CT and AA, but lower levels of TF than those prepared from wild Ganoderma species, suggesting that they have potential as nutraceuticals.Item Effects of different substrates as medium for mushrooms cultivation(Academia Publishing, 2021) Haukongo, KristineDifferent Mushrooms species prefer different substrates as growth medium. For example, medicinal mushrooms such as Shiitake, pearl and yellow oysters grow better on straws and gourmet. Reishi and Maitake grow better on sawdust and logs, whereas Agaricus mushrooms are grown on manure with the likes of button mushrooms, portobella mushrooms. As a result, mushrooms have gained interest around the world, not only because mushroom are easily cultivated using locally available agricultural waste, but also because mushrooms contribute to employment and reduce food scarcity, while meeting nutritional and health demands. In Namibia, mushroom cultivation is not well exploited due to various factors such as unfavourable climatic conditions and suitable mushroom strains. Different encroacher bushes and other related crop residues can be studied to establish the variation of mushroom nutrition and therapeutic properties as a result of mushrooms growing on different substrates. Therefore, the utilization of encroacher bushes locally could also contribute towards rangeland restoration and creating economic opportunities. This review aims at investigating the importance of mushrooms production at local levels using alternative materials as substrates in comparison to other countries as case studies.Item Cowpea production challenges and contribution to livelihood in Sub-Sahara Region(Scientific Research Publishing, 2022) Horn, LydiaCowpea [Vigna unguiculata (L.) Walp.] is an important grain legume mainly grown in tropical and subtropical regions for vegetables, grains, and fodder. The crop is grown predominantly in the dry savannahs to the Sahel in the fringes of the Sahara Desert where the annual rainfall is around 300 mm or less. Cowpea provides shelter as a cover crop and improves soil fertility by fixing atmospheric nitrogen. Its grain is preferred for high levels of protein, energy, micro-and macronutrients. Cowpea belongs to the family Fabaceae and sub-family Faboidea, and it is a self-pollinating crop with low and narrow genetic diversity, making it susceptible to various environmental factors. Various research projects have been established on cowpea, and as a result, various cowpea germplasm is stored at Africa International Institute of Tropical Agriculture (IITA)—Nigeria, the USDA repository in Griffin, GA (USA), the University of California, Riverside, CA (USA), and at the National Bureau of Plant Genetic Resources (NBPGR) in New Delhi, India. Despite the available germplasms, cowpea productivity remains very low in many countries due to a wide array of abiotic and biotic stresses and socio-economic constraints. This review summarizes some aspects of cowpea, including origin and history, challenges, economic importance, and constraints to production, providing possible useful information for cowpea researchers, agronomists, and producers in SSA.Item Exploring various promising green strategy for recycling spend mushroom substrate through desktop research analysis(Juniper Publishers, 2021) Horn, Lydia; Ueitele, Isabella S.; Nghifewa, MathewDisposal of waste generated after the harvesting of mushrooms is one of the major problems in mushroom cultivation industries. There is an urgent need for a technology that produces high-value products from the spent mushroom substrate. This need came as a result of a huge amount of spent mushroom substrate produced by the edible mushroom industry which is on an increase in many countries around the world. If not well maintained, spent mushroom substrate could cause major environmental problems which are already felt in many mushroom-producing countries. Most problems reported are associated lack of knowledge for treatment and disposal of the spent mushroom substrate. Available information has revealed that many potential agricultural and industrial uses of the spent mushroom substrate include fertilizer manufacturing, animal feed, compost for soil enrichment, treatment for coal mine drainage, bioremediation, enzyme extraction, and novel bio-sorbent. This review aims at outlining some important techniques used in making use of the biological and agricultural waste emanating from mushroom growing activities around the world. The review aims at availing some possible initiatives on reducing environmental waste through zero disposal of mushroom production waste while at the same time utilizing low-value materials to produce value-added products and generate income.Item Green synthesis of silver nanoparticles from extracts of Pechuel-loeschea leubnitziae: Their antiproliferative activity against the U87 cell line(Taylor & Francis, 2020) Mofolo, Motshewa JustinaThe application of green chemistry for the synthesis of nanoparticles is said to be environmentally friendly and cost efficient. The paper reports on the cell anti-proliferative activity of Pechuelloeschea leubnitziae, synthesis of silver nanoparticles using P. leubnitziae and characterization. The UV–vis spectroscopy confirmed presence of a peak at 400 nm, and Fourier-transform infrared spectroscopy confirmed the presence of peaks from 700-4000 cm 1 correlating to AgNPs. Presence of silver, carbon and oxygen was confirmed by X-ray photoelectron spectroscopy and Energydispersive X-ray spectroscopy. Transmission electron microscopy showed a uniform spherical particle in the size of 100 nm, and scanning electron microscope showed spherical particles at a magnification of 100 mm. The extracts and the synthesized AgNPs were tested for cytotoxicity and anti-cancer activity against the Vero and U87 glioma cell lines. The results for both cell lines indicated that dichloromethane extract and AgNPs were cytotoxic and had potential anticancer properties.Item Determination of the antiplasmodial activity, cytotoxicity and active compound of Pechuel‑loeschea leubnitziae O. Hofm. (Asteraceae) of Namibia(2020) Kadhila, Nailoke PPechuel-loeschea leubnitziae is an aromatic and unpalatable shrub traditionally used to treat malaria and related symptoms in some regions of Namibia. Despite the importance of P. leubnitziae in the management of malaria, no studies have evaluated the antiplasmodial activities of this putative antimalarial plant. In this study, antiplasmodial activity was measured using parasite lactate dehydrogenase assay. The dichloromethane crude extract of the plant showed marginal antiplasmodial activity with an IC50 of 7.24 µg/ml against Plasmodium falciparum 3D7 strain. Two fractions, Npk1 F70-77 and Npk1 F78-90, isolated from the extract exhibited enhanced antiplasmodial activity with IC50 values of 2.42±0.48 µg/ml and 2.29±0.32 µg/ml, respectively. The fractions were cytotoxic to Chinese hamster ovary mammalian cells (IC50=2.75 µg/ml and 2.22 µg/ml for NPk1 F78 and Npk1 F70, respectively). Gas chromatography–mass spectrometry, Fourier transform infrared and nuclear magnetic resonance spectroscopy confrmed that the antiplasmodial fractions of P. leubnitziae contain xerantholide (246 g/mol). This is the frst report linking xerantholide to antiplasmodial and cytotoxic fractions of P. leubnitziae. Results of this study may contribute to the discovery of new drugs from this indigenous Namibian plant.Item Green synthesis of silver nanoparticles from extracts of Pechuel-loeschea leubnitziae: Their antiprol iferative activity against the U87 cell line(2020) Mofolo, Motshewa JustinaThe application of green chemistry for the synthesis of nanoparticles is said to be environmentally friendly and cost efficient. The paper reports on the cell anti proliferative activity of Pechuelloeschea leubnitziae, synthesis of silver nanoparticles using P. leubnitziae and characterization. The UV–vis spectroscopy confirmed presence of a peak at 400 nm, and Fourier-transform infrared spectroscopy confirmed the presence of peaks from 700-4000 cm 1 correlating to AgNPs. Presence of silver, carbon and oxygen was confirmed by X-ray photoelectron spectroscopy and Energydispersive X-ray spectroscopy. Transmission electron microscopy showed a uniform spherical particle in the size of 100 nm, and scanning electron microscope showed spherical particles at a magnification of 100 mm. The extracts and the synthesized AgNPs were tested for cytotoxicity and anti-cancer activity against the Vero and U87 glioma cell lines. The results for both cell lines indicated that dichloromethane extract and AgNPs were cytotoxic and had potential anticancer properties.Item Production constraints and breeding approaches for cowpea improvement for drought prone agro-ecologies in Sub-Saharan Africa(Elsevier, 2020) Horn, LydiaCowpea [Vignaunguiculata (L.) Walp.] is an important grain legume which is widely grown in Sub-Saharan Africa (SSA) for food and feed. Its grain contains high levels of protein, energy, micro- and macro-nutrients. In SSA cowpea productivity is considerably low due to a wide array of abiotic and biotic stresses, and socio-economic constraints. This review summarizes challenges and constraints to cowpea production, breeding methods and progress, genetic variation and analysis of cowpea. Therefore, this review could serve as baseline informationItem Ganoderma research activities and development in Namibia: A review(Asian Journal of Mycology, 2021) Ueitele, Isabella S.Medicinal mushrooms have provided a natural source of bioactive compounds since ancient times. Ganoderma is such a mushroom, which has worldwide recognition as a medicinally important mushroom. In this review, the authors provide a detailed summary of indigenous Ganoderma research in Namibia, looking at the ethnomycology, biological activity, physicochemical properties, food quality and safety, as well as cultivation of this mushroom. In this paper, all available records of Ganoderma research in Namibia were retrieved from the University of Namibia Institutional Repository with the keyword “Ganoderma”. Ten theses and four peer reviewed articles with a total of 10 authors and 12 subjects, including ethnomedicinal plants, domestication, active compounds, medicinal and AIDS were reviewed. The main objective of this review is to guide researchers on the direction for future research and product development of Ganoderma in Namibia. The literature review highlights the potential to establish research and development activities of indigenous Namibian Ganoderma species. The study identifies an important knowledge gap on Ganoderma research, such as the complete morphological and molecular description of species, regulation and standardization of metabolites and characterization of novel compounds identified in indigenous Namibian Ganoderma. The domestication and cultivation of medicinal and edible mushrooms provide an excellent opportunity to contribute to the United Nations Sustainable Development Goals of promoting good health and well-being (SDG 3), nutrition (SDG 2: Zero Hunger), and income generation (SDG 1: no poverty).Item The effect of single and combined use of gamma radiation and ethyl methane sulfonate on early growth parameters in Sorghum(mdpi, 2020) Wanga, Maliata AAbstract: Success in inducing genetic variation through mutagenic agents is dependent on the source and dose of application. The objective of this study was to determine the optimum doses of a single and combined use of gamma radiation and ethylmethane sulfonate (EMS) for effective mutation breeding in sorghum. The study involved two concurrent experiments as follows: in experiment I, the seeds of four sorghum genotypes (‘Parbhani Moti’, ‘Parbhani Shakti’, ‘ICSV 150130, and ‘Macia’) were treated using gamma radiation (0, 300, 400, 500 and 600 Gy), EMS (0, 0.5 and 1.0%), and gamma radiation followed by EMS (0 and 300 Gy and 0.1% EMS; 400 Gy and 0.05% EMS). In experiment II, the seeds of two genotypes (‘Macia’ and ‘Red sorghum’) were treated with seven doses of gamma radiation only (0, 100, 200, 300, 400, 500 and 600 Gy). Overall, the combined applied doses of gamma radiation and EMS are not recommended due to poor seedling emergence and seedling survival rate below LD50. The best dosage of gamma radiation for genotypes Red sorghum, Parbhani Moti, Macia, ICSV 15013 and Parbhani Shakti ranged between 392 and 419 Gy, 311 and 354 Gy, 256 and 355 Gy, 273 and 304 Gy, and 266 and 297 Gy, respectively. The EMS optimum dosage ranges for genotypes Parbhani Shakti, ICSV 15013, Parbhani Moti and Macia were between 0.41% and 0.60%, 0.48% and 0.58%, 0.46% and 0.51%, and 0.36% and 0.45%, respectively. The above dose rates are useful to induce genetic variation in the tested sorghum genotypes for greater mutation events in sorghum breeding programs. Keywords: ethylmethane sulfonate; gamma radiation; sorghumItem FLASH: a next-generation CRISPR diagnostic for multiplexed detection of antimicrobial resistance sequences(2019) Quan, Jenai; Langelier, Charles; Mumbengegwi, Davis R.The growing prevalence of deadly microbes with resistance to previously life-saving drug therapies is a dire threat to human health. Detection of low abundance pathogen sequences remains a challenge for metagenomic Next Generation Sequencing (NGS). We introduce FLASH (Finding Low Abundance Sequences by Hybridization), a nextgeneration CRISPR/Cas9 diagnostic method that takes advantage of the efficiency, specificity and flexibility of Cas9 to enrich for a programmed set of sequences. FLASH-NGS achieves up to 5 orders of magnitude of enrichment and sub-attomolar gene detection with minimal background. We provide an open-source software tool (FLASHit) for guide RNA design. Here we applied it to detection of antimicrobial resistance genes in respiratory fluid and dried blood spots, but FLASH-NGS is applicable to all areas that rely on multiplex PCR.Item In vitro induction of auto‑allotetraploid in a newly developed wild rice line from Oryza alta Swallen(2019) Zhang, Liusheng; Shivute, Fimanekeni Ndaitavela; Shahid, Muhammad Qasim; Kamara, Nabieu; Wu, Jinwen; Liu, XiangdongOryza alta Swallen is an important germplasm for rice resistance breeding; however, its CCDD genome (2n = 48) resulted in low crossability when the wild rice was crossed with O. sativa and restricted the success of transferring the desirable traits into cultivated rice. Induction of polyploidy is an efficient way for overcoming the low crossability among different species. A new O. alta line, Huaye 5, was developed by our group in 2016, which had high fertility (64.93%) and photoperiod-insensitive. Huaye 5 was used to induce auto-allotetraploidy using tissue culture in the present study. The tissue culture system was established by comparing five basic media (N6, B5, MS, NB and MB), two hormones (2,4-D and 6-BA) for induction and two differentiation media (MS and NB), and then induced auto-allotetraploid in the wild rice line by colchicine. The medium and hormone combinations of NB + 2,4-D (2.5 mg/L) + 6-BA (1.0 mg/L) produced the induction rate of 20%, and MS medium was found to be a suitable medium for callus induction with a differentiation rate of 10.15%, and the treatment of 600 mg/L colchicine for 24 h was the best protocol for inducing auto-allotetraploid. Subsequently, auto-allotetraploid plants (2n = 96) were obtained in the present study and their ploidy levels were detected by using flow cytometry, stomata size and chromosomes count methods. Many inclusions in the parenchyma cells surrounding vascular bundle were observed in auto-allotetraploid rice compared to the parent. We developed a new germplasm from O. alta, and established a protocol of in vitro induction of auto-allotetraploid, which can be used for crossing with autotetraploid rice.Item Molecular phylogeny of Trametes and related genera from northern Namibia(2018) Ueitele, Isabella S.; Chimwamurombe, Percy M.; Kadhila-Muandingi, Nailoke P.Trametes Fr. is widely characterized as a polyporoid cosmopolitan genus which is presented in almost any type of forest environments. It is characterized by a combination of pileate basidiocarp, porous hymenophore, trimitic hyphal system and thin-walled basidiospores which do not react in Melzer’s reagent. Dry polypores were collected from Northern Namibia and identified as Trametes species based on morphology. Molecular analysis of Internal Transcribed Spacer region 1 (ITS 1) and Internal Transcribed Spacer region 2 (ITS 2) of the collected material revealed inconsistency with morphological identification. The phylogenetic tree was reconstructed using the Neighbour Joining method and reliability for internal branches Assessment was done using the ML bootstrapping method with 500 ML bootstrap replicates applied to 44 unpublished sequences and sequences from GenBank database. Only specimens such as D1-D9, D11 and D13 and specimens F1, I2-I4 and K3-K6 were grouped in the trametoid clade together with Trametes species. Furthermore, the position of Trametes trogii (also known as Coriolopsis trogii) was confirmed to be outside the trametoid clade and more closely related to Coriolopsis gallica. The close relationships of Pycnoporus and Trametes were confirmed by grouping of Pycnoporus sanguineus in to trametoid clade. Alignment with GenBank sequences revealed identity to Trametes species with up to 99%. These results suggest that it is better to keep a single generic name of Trametes for the trametoid clade.Item Minerals and trace elements in domesticated Namibian Ganoderma species(2015) Mhanda, F.N.; Kadhila-Muandingi, Nailoke P.; Ueitele, Isabella S.Edible and medicinal mushrooms are regarded as the ideal health foods. They are well appreciated for their exquisite taste and flavor and are consumed both fresh and in processed forms. Nutritive value of mushrooms is attributed to their high content of essential amino acids, vitamins, minerals and low lipid content. Regular consumption of whole medicinal and edible mushrooms could introduce a functional or medicinal contribution within the individual’s diet. Medicinal mushrooms may prevent or treat "lifestyle-related diseases". The extent of the health beneficial effect will depend on the level, regularity of consumption, the relevance of medicinal mushrooms and concentrates to the particular disease. The minerals and trace elements in domesticated Namibian Ganoderma mushroom species were determined. The results show that fiber content was found highest with 45 g/100 g of dry weight, followed by calcium with 23 g/100 g, carbohydrate with 23 g/100 g, protein with 18.2 g/100 g, iron with 6.41 g/100 g, copper with 4.3 g/100 g while the least were zinc (2.89 g/100 g) and fat (1.9 g/100 g). The presence of these essential nutrients, which are nutritional requirements of human beings, implies that Ganoderma can be a valuable dietary supplement to boost the immune system and improve general health of people. It was therefore concluded that the domesticated Ganoderma has significant amount of nutrients that makes it a good fungus to be used on daily bases for health benefit.