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Item Africa’s Mushrooms: A Neglected Bioresource whose Time has Come(Africa’s mushrooms, 2003) Mshigeni, Keto E.Some of our readers, after assimilating the message contained in the Editorial of the last issue of our journal (Discovery and Innovation, Vol. 15 Number 1/ 2, pp. 1-7), “Surprises, scientific charm, socio-economic potential, and possibilities in the mushroom world”, wrote back, excited. One asked for more information on the Chinese mushroom farming experience with a view to exploring how Africa could also make it. Another wrote on the reticulately veiled mushroom collected from western Uganda, the edible Dictyophora mushroom, which had been mentioned in the previous Editorial. One who had read our other publications on Africa’s mushroom resources, had exciting novel information to share about one of Africa’s neglected wild mushrooms: GanodermaItem Coelarthrum boergesenii (Rhodophycophyta, Rhodymeniales): a new record from Tanzania(Botanica Marina, 1981) Mshigeni, Keto E.A study has been conducted on specimens of a marine red alga collected by G. F. Papenfuss and R. F. Scagel in Tanzania during the International Indian Ocean Expedition in 1962. The thallus of the alga is small (2-3 cm tall), with a segmented construction and constrictions along the axes. Its branches arise mainly on the segments, and these often anastomose making it difficult to separate individual axes. Anatomically the axes have an epidermal layer ofsmall cells (3—5 μιη in diameter) and a cortex with outer smaller (8—20 μτη in diameter) and inner larger (70—150 μπ\in diameter) cells. Some of the inner cortical cells bear deeply staining gland cells, which are 9—12 μιη in diameter. The alga was identified as Coelarthrum boergesenii Weber-van Bosse, and is here reported as a first record of the genus in Tanzania.Item Contributions on the Content and Nature of the Phycocoiloid from Laurencia papillosa (Forssk.) Greville (Rhodophyta, Ceramiales)(Botanica Marina, 1977) Mshigeni, Keto E.The content, infrared spectroscopy, total sulphate and optical rotation of the phycocolloid from Laurencia papillosa (Forssk.) Grevüle from Tanzania have been investigated. A phycocolloid yield of 33.6 ± 0-6% was obtained on a dry weight basis. The total sulphate content of the phycocolloid was 16.8 ± 0.4% and the optical rotation was found to be negative [a|D5 - 5.5 °. The phycocolloid was soluble in potassium Chloride. Its IR spectra showed absorptionpeaks more akin to -than -or -cairageenan. A detailed discussion of these findings is presented.Item Contributions on the content and nature of the Phycocolloid from Halymenia venusta Boergesen (Rhodophyta, Cryptonemiales)(Botanica Marina, 1977) Mshigeni, Keto E.The phycocolloid from Halymenia venusta Boergesen has been studied and found to be a carrageenan which is morecloscly related to y-than k-carrageenan. A total phycocolloid yield of 59.0 ± 2.5 % on dry weight basis was obtained.The presence of a cold water-soluble phycocolloid in the thaüi of H. venusta was also discovered and its IR spectrum determined.Item Contributions to the Embryology of Padina gymnospora (Phaeophyta, Dictyotales)(Botanica Marina, 1978) Mshigeni, Keto E.Abstract The pattern of tetraspore germination and early stages of development in Padina gymnospora (Kuetzing) Vickers (Phaeophyta, Dictyotales) have been investigated for a period of seven weeks. The early stages of development were äs earlier reported for other Dictyotales. However, new findings were found with respect to shoot differentiation. The erect shoots were initiated both from the meristematic activity of the ‘Central nodule' and from shoot initials which developed at intervals along the length of the rhizoids. The biological significance of the rhizoidal shoots is discussedItem Effects of the environment on developmental rates of sporelings of two Hypnea species (Rhodophyta: Gigartinales)(Marine Biology, 1976) Mshigeni, Keto E.Growth of sporelings of Hypnea cervicornis J. Agardh and H. chordacea Kuetzing in response to gradients of selected environmental factors has been investigated. The sporelings of H. cervicornis tolerated higher levels of the tested parameters (e.g. salinity and temperature) than those of H. chordacea. In all the treatments, the sporelings of H. cervicornis grew significantly faster than those of H. chordacea. The ecological and agronomic implications of these findings are discussed.Item Field Cultivation of Hypnea (Rhodophyta) Spores for Carrageenan: Prospects and Problems(Botanica Marina, 1976) Mshigeni, Keto E.Carpospores and tetraspores ofHypnea cervicornis J, Agardh have been cultivated in the fieid. These developed intoadult fronds in thiee months. This implies that where nutrients or other environmental factors are not limiting, it ispossible to raise four harvestable crops of Hypnea from spores per year, Since carpospores gave rise to tetrasporo-phytes and tetraspores produced gametophytes, it was concluded that the life history of the species is of the Poly-siphonia-typeItem Field Observations on the Colonization of New Substrata and Denuded Intertidal Surfaces by Benthic Macrophytic Algae(Botanica Marina, 1978) Mshigeni, Keto E.Investigations have been conducted on the colonization of new substrata (brick surfaces) and recolonization of denudedintertidal surfaces by frondose benthic algae on the tropical shores of Hawaii. Size measurements of the benthic algaecolonizing the habitats are presented and agronomic implications of the research findings are discussedItem Holdfast and Shoot Differentiation in the Sporelings of Hypnea cervicornis J. Agardh (Rhodophyta, Gigartinales)(Botanica Marina, 1976) Mshigeni, Keto E.Holdfast and shoot differentiation in the Sporelings of Hypnea cervicornis J. Agardh has been investigated for the first time. It was observed that the holdfasts of this species are not simple unicellular structures but consist of large masses of cells differentiated from amongst the superficial cells at the points of contact with the substratum. After or during holdfast differentiation, the morula-like mass of cells produced shoot Initials. One to four Initials were ob-served. When three or more initials were differentiated at the same time, stellate stages were formed. The stellate stages in Hypnea ontogeny are discussed with reference to similai structures reported in taxonomic literature äs diagnostic criteria for H. cornuta (Lamour.) J. AgardhItem Information and Communication Technology (ICT) and economic Ddevelopment: a framework for change in developing countries(Discovery and Innovation, 2002) Mshigeni, Keto E.Information and Communication Technology (ICT) can be used to accelerate economic development. For many developing countries however, the potential of ICT for economic development has not been fully realized Numerous studies have attempted to examine the underlying problems from different perspectives. While these studies are extremely useful, few examine the situation in its entirety. Researchers who have taken concern on issues of the digital divide, as it is called, have generally worked in isolated areas. There is therefore, a needfor concerted work that investigates how all the different aspects of ICT interrelate to influence economic development. Such an analysis will help developing countries to direct their efforts and resources towards ICT. In this regard, a broader perspective is presented in this paper to examine the relationship between ICT and economic development in a comprehensive manner. An attempt has been made to mention broadly, some work that has been done in different areas of ICT within the comprehensive perspective developed, while areas needing more attention are also identified. From this perspective, efforts can be made to enhance each of the different elements, knowing how they relate in the entire development paradigm. This approach will improve the impact of ICT on economic development. Keywords: information and communication technologies, economic development, developing countries development paradigmItem Inventory of plants used in traditional medicine in Tanzania. I. Plants of the families acanthaceae-cucurbitaceae(Journal of ethnopharmacology, 1982) Mshigeni, Keto E.Sixty-two plants are listed, which are used by traditional healers in the northeastern part of Tanzania. For each species are given: the botanical name with synonyms, vernacular name, collection number, locality, habitus, approximate distribution, and medical use. Results of a literature survey are also reported, including medical use, isolated constituents and pharmacological effectsItem Inventory of plants used in traditional medicine in Tanzania. II. Plants of the families dilleniaceae—Opiliaceae(Journal of Ethnopharmacology, 1983) Mshigeni, Keto E.Forty five plants are listed, which are used by traditional healers in the northeastern part of Tanzania. For each species are given: the botanical name with synonyms, vernacular name, collection number, locality, habitus, approximate distribution and medical use. Results of a literature survey are also reported, including medical use, isolated constituents and pharmacological effects.Item Inventory of plants used in traditional medicine in Tanzania. Part III. Plants of the families papilionaceaevitaceae(Journal of Ethnopharmacology, 1983) Mshigeni, Keto E.Forty-six plants are listed, which are used by traditional healers in the northeastern part of Tanzania. For each species are given: the botanical name with synonyms ; vernacular name ; collection number; locality; habitus; approximate distribution and medical use. Results of a literature survey are also reported, including medical use, isolated constituents and pharmacological effectsItem The morphology and distribution ecology of Corynomorpha prismatica: A red seaweed of potential economic significance in southeast Tanzania(Marine Biology, 1977) Mshigeni, Keto E.Investigations have been conducted on the gross morphology and distribution ecology of Corynomorpha prismatica J. Agardh (Rhodophyta, Cryptonemiales) at Lindi, southeast Tanzania. The mean standing crop of the seaweed in the study locality was 518±80.2 g/m2 dry weight. Frond height varied as a function of habitat elevation, being 21.2±1.3, 20.2±2.0, 13.7±2.5 and 4.3±0.4 cm at-15, 5, 25 and 45 cm elevation above spring-tide low-water mark, respectively. Populations of C. prismatica were almost exclusively confined to west-facing vertical rocky surfaces sheltered from direct insolation during the morning hours. The fronds showed a wider variety of morphological appearance than reported in the literature. This was partly due to variations in the patterns of thallus regeneration after wounding. The economic implications of these findings are discussed.Item A note on the fate of tetrasporangial stichidia in Hypnea Lamouroux after spore release(Botanica Marina, 1976) Mshigeni, Keto E.The fate of the tetrasporangial Stichidia has been investigated in Hypnea cervicornis and H. chordacea. It was foundthat Stichidia are not determinate branchJets äs was once thought, but continue with vegetative giowth after sporeshedding, Even where the Stichidia became detached from the main axes after spore shedding, they developed newholdfasts and grew into new thalli.Item On the ultrastructure of the cell wall and pit plugs of Chondrococcus hornemannii (Rhodophyta, Cryptonemiales)(Botanica Marina, 1977) Mshigeni, Keto E.The Ultrastructure of the cell wall of Chondrococcus hornemannii is being reported for the first time. Amongst the notable features revealed in this study are: the stratified appearance of the wall, the presence of distinct lenticular pit plugs where the wall is interrupted by pit connections, and the presence of floridean starch grains scattered in the cytoplasm.Item Revision of the Red Algal Genus Galaxaura with Special Reference to the Species Occurring in the Western Indian Ocean(Botanica marina, 1982) Mshigeni, Keto E.A study of Galaxaura (Nemaliales, Chaetangiaceae) from Hast Africa (especially Tanzania, Mozambique, South Africa and Malagasy Republic) and Mauritius has revealed that the following nine taxa are represented: G. diesingiana Zanardini, G. fasciculata Kjellman, G. lapidescens (Ellis et Solander) Lamouroux, G. lenta Kjellman, G. margifiata (Ellis et Solander) Lamouroux, G, oblongata (Ellis et Solander) Lamouroux, G. obtusata (Ellis et Solander) Lamouroux, G. rugosa (Ellis et Solander) Lamouroux and G, subverticillata Kjellman. The species recognized include seven of the 62 treated by Kjeilman in 1900 and two species not treated by him. The nine species encompass 38 species reported by various authors for the region. A key to the species, comments on their morphology, illustrations of their growth habit and structure, and discussions of their taxonomy and nomenclature are presented.Item Seasonal Changes in the Standing Crops of Three Hypnea Species (Rhodophyta: Gigartinales) in Hawaii(Botanica Marina, 1977) Mshigeni, Keto E.Studies have been conducted on Standing crops of Hypnea cervicornis J. Agardh, H. chordacea Kützing and H. nidifica J. Agardh in Hawaii. AH the three species showed Standing crop seasonality. The standing crops rcachedtheür maxima during winter (November to Januaiy). From January to May they showed a steady decline. The relationship between standing crops and seasonal changes in tidal behaviour is discussed.Item Seaweed farming: a possibility for Tanzania's coastal Ujamaa villages(Tanzania Notes and Records, 1976) Mshigeni, Keto E.Tanzania is fortunate in having a relatively long shoreline and many offshore islands which support appreciable quantities of seaweeds. One of the most notable seaweeds is the genus Eucheuma which has been harvested from the shores of Zanzibar, Pemba and Mafia Islands for over two decades. About 500 to 800 tons of dry Eucheuma are exported from Tanzania to Western Europe annually. The cells of this seaweed contain the industrial phycocolloid carrageenan, which has a wide range of applications in food, pharmaceutical and textile industries. It is likely that Eucheuma farming is a possible economic activity in Tanzania. In order to teach the farming techniques efficiently, it would seem desirable to establish the farms in some selected Ujamaa villages along the coast where the people to be recruited can be selected from amongst those already experienced with marine life, such as fishermen or shell-collectors.Item Solieria jaasundii, a new species of red algae (Gigartinales, Solieriaceae) from Tanzania(Solieria jaasundii, a New Species of Red Algae (Gigartinales, Solieriaceae) from Tanzania, 1981) Mshigeni, Keto E.An anatomical study of a marine red alga from Tanzania, which was previously identified as Rhabdonia Africana Jaasund, has shown the alga to be a new species of Solieria. Its thallus has a segmented construction, with regular constrictions along the axes, and its branches arise mainly at the constrictions. Internally the thallus shows a central, loosely-packed mass of medullary filaments, which are joined to one another by interconnecting strands like those known to occur in some members of the Solieriaceae, e. g., Solieria robusta. External to the medulla is a cortex composed of cells that are shorter but wider in diameter. The cortical cells progressively decrease in size outwardly. Stellate cells whose arms serve as interconnecting points between the cortex and the medulla are common. Thecortical cells contain numerous coiled, ribbon-like structures similar to those in Rhabdonia verticillata (Min-Theinand Womersley 1976). These are interpreted as chromatophores. The anatomy of the central part of the medulla and of the thallus apices shows the plant to be multiaxial in construction. A discussion of the findings is presented, and a new name for the alga, Solieria jaasundii sp. nov., is proposed