Browsing by Author "Ndakidemi, Patrick A."

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Acute oral toxicity study of Mystroxylon aethiopicum root bark aqueous extract in albino mice
(Journal of Medicinal Plants Research, 2016-10-03) Kilonzo, Mhuji; Ndakidemi, Patrick A.; Chacha, Musa
Acute oral toxicity of Mystroxylon aethiopicum root bark aqueous was evaluated in albino mice of either sex. In this study, five groups of mice were orally treated with doses of 1000, 2000, 3000, 4000 and 5000 mg/kg body weight of crude extract. The mortality, signs of toxicity and body weights were observed individually for two weeks. At the end of the two weeks study, all animals were sacrificed and the hematological and biochemical parameters as well as organ weights relative to body weight of each animal were determined. No mortality, signs of toxicity and abnormalities in vital organs were observed in the entire period of study for both treated and control groups of mice. Additionally, there were no significant changes (p>0.05) in the blood hematology and biochemical analysis. However, the body weights of all mice increased significantly. The M. aethiopicum root bark aqueous extract were found to have a high safe margin when administered orally. Hence, the extract can be utilized for pharmaceutical formulations.
Allelopathic Effects of Sphaeranthus suaveolens on Seed Germination and Seedling Growth of Phaseolus vulgaris and Oryza sativa
(Hindawi, 2021-02-15) Laizer, Hudson C.; Chacha, Musa; Ndakidemi, Patrick A.
Weeds with allelopathic effect have been reported to cause significant damage in agriculture particularly in smallholder farming systems. ,is study assessed the allelopathic effects of different concentrations of crude extract of a noxious weed Sphaeranthus suaveolens on seed germination and seedling growth of Phaseolus vulgaris and Oryza sativa by examining germination, seedling height, and total chlorophyll content after seven and fourteen days of crude extract treatment, respectively. Results showed that seed germination and seedling growth were significantly (p < 0.001) decreased with increase in concentration of crude extract, signifying concentration dependency. Highest concentration (100%) of S. suaveolens crude extracts resulted in 90% and 100% inhibition of P. vulgaris and O. sativa seed germination, respectively. Chlorophyll content, fresh weight, and root and shoot length of both P. vulgaris and O. sativa were also significantly (p < 0.001) affected by highest concentration (100%) of S. suaveolens crude extracts. Results from this study suggest that the extract of S. suaveolens contains water-soluble allelochemicals which significantly reduce growth and productivity of P. vulgaris and O. sativa.
Anthropogenic Pressure on Tree Species Diversity, Composition, and Growth of Balanites aegyptiaca in Dinder Biosphere Reserve, Sudan
(MDPI, 2021-03-04) Mohammed, Elmugheira M. I.; H., Elhag A. M.; Ndakidemi, Patrick A.; Treydte, Anna C.
Anthropogenic disturbances, such as illegal harvesting and livestock browsing, often affect natural forests. However, the resulting tree species diversity, composition, and population structure have rarely been quantified. We assessed tree species diversity and importance value indices and, in particular, Balanites aegyptiaca (L.) Del. population structure, across 100 sample plots of 25 m × 40 m in disturbed and non-disturbed sites at the Dinder Biosphere Reserve, Sudan, from April 2019 to April 2020. We found that the tree species diversity in non-disturbed sites was more than double that of disturbed sites (p < 0.001, T = 32.6), and seedlings and saplings comprised more than 72% of the entire tree population (F2,48 = 116.4, p = 0.034; F2,48 = 163.2, p = 0.021, respectively). The tree density of B. aegyptiaca in the disturbed site was less than half that of the non-disturbed site (p = 0.018, T = 2.6). Balanites aegyptiaca was seven times more aggregated in disturbed sites compared to more regularly spaced trees in non-disturbed sites (T = 39.3 and p < 0.001). The poor B. aegyptiaca population status of the disturbed site shows that the conservation of this vulnerable species is essential for a sustainable management and utilization scheme.
Biovar 2 of Ralstonia solanacearum Species Complex Causes Tomato Bacterial Wilt Disease in Tanzania
(Science Alert, 2020-03) Aloyce, Agatha; Ndakidemi, Patrick A.; Mbega, Ernest
Background and Objective: Bacterial wilt disease (BWD) caused by complex species of Ralstonia solanacearum (RSSC) has been categorized as one of the most significant plant diseases in the world. It is a serious problem of tomato and causes significant economic losses of tomato in Tanzania. The purpose of this study was to determine biovars of RSSC causing tomato BWD in Tanzania. Materials and Methods: Tomato stems showing typical symptoms of BWD were collected from main agro-ecological regions and were characterized by pathological and carbohydrate oxidation tests. The least significance difference (LSD) procedure was used for mean separation (p = 0.05) of disease incidence and severity. Results: A total of 29 out 40 RSSC isolates from infected tomato stems produced typical colonies of RSSC on triphenyl tetrazolium chloride medium out of which 19 (52%) were pathogenic on tomato variety Tanya. Carbohydrate oxidation test showed that most (90%) predominating isolates in main agro-ecological regions belong to biovar 3 while the rest (10%) belong to biovar 2 and prevail in the southern zone of Tanzania. This is the first report of prevalence of biovar 2 of Ralstonia in Tanzania and suggests a recent introduction of biovar 2 in tomato fields in Tanzania. Conclusion: Biovar 2 of RSSC is reported for the first time to cause tomato bacterial wilt disease in Tanzania. This alerts plant health regulators to embark on necessary phytosanitary measures to prevent further spread and/or introduction of the disease considering its quarantine status in different countries.
Changing Patterns and Drivers of Increased Pesticides Use in Smallholder Vegetable Production Systems in Tanzania
(BioRxiv, 2021-01-18) Kapeleka, Jones A.; Sauli, Elingarami; Sadik, Omowunmi; Ndakidemi, Patrick A.
Pesticides use has become a key component of smallholder horticulture production. Therefore, dynamics in pesticides handling need to be ascertained. This study assessed drivers of pesticides use and determinants of changing patterns of pesticides handling practices in smallholder vegetable systems. Data were collected from 385 farmers from Iringa, Arusha, Manyara, and Kilimanjaro regions in Tanzania through an in-depth survey and field observations. A binary probit model was used to derive factors fostering increased pesticides use. Results showed that 47.9 % of all pesticides were wrongly used. Most farmers (88.6%) lacked knowledge of pest control and 88.9% were unaware of safety practices. Disposal methods of empty pesticides foster occupational and environmental exposure (58%). There was an increasing trend in pesticides use (58.4%), accompanied by changing pesticides formulations. Over 60 pesticides with 29 different formulations were used. Mixing pesticides (71.2%), high dose rates with increased frequency of application were observed. Pesticides under Class II WHO hazard (68.9%) dominated. Extremely hazardous (Class Ia) and highly hazardous (Class Ib) were also used. Binary probit model showed that number of crops grown, pesticides mixing, and region contributed positively to the likelihood of increased pesticides use while farmers’ perception of effectiveness of pesticides, lack of access to safe use information, poor use of safety gears and inability to read pesticides labels had a negative impact. The fate of pesticides use in smallholder vegetable production systems is therefore the culmination of serious health and environmental implications. Excessive pesticides use escalated by increased number of crops, improper use of PPE, and pesticides mixing practices subjects the general population to pesticides environmental exposure thereby jeopardizing sustainability of smallholder vegetable production in Tanzania. Regular training to farmers and extension officers on current and emerging issues on pests and pesticide safe use is vital.
Importance of common bean genetic zinc biofortification in alleviating human zinc deficiency in sub-Saharan Africa
(Taylor & Francis Online, 2021-04-04) Philipo, Mashamba; Ndakidemi, Patrick A.; Mbega, Ernest
Zinc deficiency is among the leading risks to human health in sub-Saharan Africa, its adverse exposure leads to diarrhea, pneumonia, and malaria. Furthermore, it is the leading cause of stunting in children and negatively influences the human immune system, body iron, and vitamin A and D. High zinc deficiency in sub-Saharan Africa is due to the consumption of staple foods with low zinc contents. Genetic zinc biofortification of common bean among staple food crops is the best approach for alleviating zinc deficiency, as it is cost-effective and can easily reach low-income households. Genetic zinc biofortification by conventional breeding coupled with marker-assisted selection is the best strategy for sub-Saharan Africa, as the selection of crosses is precise and takes short time to develop high zinc-containing varieties. Zinc content increase in common bean seeds has a high impact on alleviating zinc deficiency as it is consumed whole compared to cereal grains which undergo milling, the process that removes zinc-rich parts before being consumed. This review explains the current status of zinc deficiency in sub-Saharan Africa, conventional methods for alleviating the problem, current and potential of modern genetic approaches for zinc biofortification of common bean in alleviating zinc deficiency in the region.
Livestock Browsing Threatens the Survival of Balanites aegyptiaca Seedlings and Saplings in Dinder Biosphere Reserve, Sudan
(Taylor & Francis Online, 2021-06-03) Mohammed, Elmugheira M. I.; Hammed, Abbas M. E.; Minnick, Tamera J.; Ndakidemi, Patrick A.; Treydte, Anna C.
While the impact of livestock grazing has been frequently assessed for grasses, little is known about how livestock affects tree seedlings and saplings. We explored the effects of goat, cattle and camel browsing on the survival of Balanites aegyptiaca seedlings and saplings, a broadleaved evergreen tree species indigenous to Sudan, in Dinder Biosphere Reserve-Sudan (DBR). We used a stratified sampling design with four sites: GOA (mainly browsed by goats), CAT and CAM being mainly browsed by cattle and camels, respectively, while CON was a control area without any livestock browsing. We tested the survival, mortality and recovery of seedlings and saplings across different sites. Our results revealed that mortalities of seedlings in GOA were almost four times higher than that of CAM and CON and twice that of CAT (F3,196 = 100.39, P < .001). Further, sapling mortality was three times higher in GOA than that observed in CAT and CON (F3,196 = 73.4, P < .001). We found that seedlings recover better than saplings, and, unexpectedly, goat browsing severely affected the natural regeneration of B. aegyptiaca in DBR compared to other livestock species. Our study findings contribute to sustainable forest management and show that particularly goat browsing needs to be suppressed for conservation of vulnerable tree species.
Maize (Zea mays) Response to Anthill Soil (Termitaria), Manure and NPK Fertilization Rate under Conventional and Reduced Tillage Cropping Systems
(MDPI, 2020-01-27) Chisanga, Kafula; Mbega, Ernest; Ndakidemi, Patrick A.
Soil fertility management has been described by many scholars as fundamental and a major hindrance to food production amongst smallholder farmers in the developing world. To counteract this challenge, some farmers have been reported to use anthill soil as analternative fertilizer to improve soil fertility for supporting crop growth. Against this background, a study was undertaken with the aim of ascertaining the effect of anthill soil application alone, cattle manure, and/or their combination with commercially available NPK fertilizer on the growth and yield parameters of three maize varieties under field conditions involving conventional (CONV) and conservation agriculture (CA) tillage systems. Results revealed that anthill soil alone (5000 kg/ha) or in combination with either manure (10,000 kg/ha) or half rate of commercially available fertilizer (NPKS: 10% N, 20% P2O5, 10% K2O, 6% S at 100 kg/ha) competed favourably in terms of response to growth parameters. Furthermore, pH and P levels changed significantly (p < 0.05) at harvest. We conclude that resource-constrained smallholder farmers in less developed countries utilizing anthill soil for fertility improvement purposes should judiciously apply it in CA planting basin structures compared with conventional methods, which appeared to be less effective and leads to sub-optimal yields.
Phytochemical analysis and in vitro antifungal evaluation of Jatropha curcas against Late Leaf Spot disease on groundnut
(Journal of Animal & Plant Sciences, 2021-01-31) Francis, Magreth; Chacha, Musa; Ndakidemi, Patrick A.; Mbega, Ernest
This study was done to evaluate the antifungal efficacy of Jatropha curcas leaf extracts against groundnut late leaf spot disease caused by Phaeosariopsis personata (P. personata) and identify their bioactive compounds responsible for antifungal effects. Jatropha curcas leaves extracted sequentially through chloroform, ethyl acetate and methanol solvents were evaluated against the mycelial growth of P. personata by food poisoning method. About 0.1, 0.25 or 0.5 mg/ml (plant extract/water) of each extract were mixed in molten PDA poured into Petri dishes. Thereafter solidified amended PDA with extracts was kept at room temperature for 24 hours. A seven-day-old fungal plug (4mm diameter) of P. personata was plated at the middle of the Petri dishes in triplicates. Inoculation on PDA plates amended with fungicide Chlorothalonil (720g/L) or water was included as positive and negative control respectively. The results proved that J. curcas leaf extracts possessed fungicidal properties since they inhibited the growth of P. personata. Moreover the antifungal effect of J. curcas leaf extracts increased as concentration increased. Moreover, J. curcas leaf extracts highly inhibited mycelial growth by (85.78%) similar to standard fungicide (chlorothalonil) (88.37%) in this experiment. The presence of important compounds found in J. curcas leaf extracts by GC-MS supported their ability against P. personata pathogen. Among the major compounds identified with antifungal activity were hexadecanoic acid methyl ester, hexadecanoic acid ethyl ester, hexadecane, n-hexadecanoic acid, octadecanoic acid ethyl ester, phytol and 9, 12- octadecadienoic acid (Z,Z)-methyl ester. The potentiality of J. curcas extracts in managing groundnut late leaf spot disease was confirmed by their ability to inhibit the growth of P. personata and possession of important phytochemical compounds.
Rooting and growth potential of Leucadendron laxum (proteaceae) using different rooting mediums and indoleacetic acid growth regulators
(Sabinet African Journals About Sabin, 2009-01-01) Laubscher, Charles Petrus; Ndakidemi, Patrick A.
Leucadendron laxum (Proteaceae) is a South African plant species with a high commercial value as a flowering potted plant. Limited research information on the culture and propagation of this species is available in South Africa. The application of rooting hormone indole acetic acid (IAA) in various rooting mediums in L. laxum was tested. The treatments included: control, 500, 1000, 2000 and 4000 ppm, and four rooting mediums: a) bark / polystyrene; b) peat moss / polystyrene; c) bark / river sand / polystyrene; and d) perlite / river sand. A randomised block design with three replicates was used. Compared with other mediums, bark and polystyrene had the highest significant results in root and shoot growth, and the percentage that callused, rooted and survived. The IAA treatments at different concentrations had significant effects on rooting, callusing, shoot growth, root lengths and numbers of roots per cutting.
Socio-Economic Factors for Anthill Soil Utilization by Smallholder Farmers in Zambia
(MDPI, 2019-09-05) Chisanga, Kafula; Mbega, Ernest; Ndakidemi, Patrick A.
In this study, we surveyed two districts of Zambia—Choma and Pemba. The aim of this study was to obtain the perspective of farmers on anthill soil utilization practices for key information that could contribute towards the development of an anthill soil based research agenda. The study employed both a qualitative and quantitative method approach to gather data from the respondents, which included farmers and key informants. Qualitative data was analyzed using the triangulation method and Computer Assisted Qualitative Data Analysis Software (CAQDAS), Nvivo version 10, while data generated from quantitative interviews with a smart phone Application (Open Data Kit) were analyzed using Statistical Package for Social Sciences (SPSS). Results revealed that the key hurdles to the utilization of anthill soil lay in agro-climatic, biophysical, technological, land and institutional constraints. Broadly, farmers reported poor rainfall patterns (95%), decreasing soil fertility (70%), limited farm products (69%), finance (66%), limited access to research and extension services (55%) and security of land tenure (48%) as major constraints. We therefore advocate for strengthenedinstitutional linkages between research and extension for information dissemination, which would aid in decision-making used to promote integrated soil fertility management for improved agriculture production and productivity of rural households.
Tomato Leafminer (Tuta absoluta Meyrick 1917): A Threat to Tomato Production in Africa
(Journal of Agriculture and Ecology Research International, 2016-11-28) Zekeya, Never; Chacha, Musa; Ndakidemi, Patrick A.; Materu, Chris; Chidege, Maneno; Mbega, Ernest
Tomato (Solanum lycopersicum L.) is an important vegetable crop for income, food and nutrition in Africa. Production of the crop is currently threatened by leaf miner [Tuta absoluta (Meyrick) (Lepidoptera: Gelechiidae)]. Heavy infestation by T. absoluta has been reported to cause yield losses ranging from 80-100%. Tuta absoluta has high rate of reproduction and short life cycle making it very dominant in the infested tomato fields. Insecticide application for control of the pest is uneconomical for subsistence farming and beyond the earnings of majority of resource-poor farmers in Africa. Use of host resistance and or integrated pest management (IPM) strategies is slightly or not in use thus making the pest reign in the majority of African countries. This review discusses how T. absoluta threatens production and recommends some focal areas towards addressing this pest problem in the tomato industry in Africa.
Tomato Leafminer, Tuta absoluta (Meyrick 1917), an emerging agricultural pest in Sub-Saharan Africa: Current and prospective management strategies
(Academic Journal, 2017-02-17) Zekeya, Never; Ndakidemi, Patrick A.; Chacha, Musa; Mbega, Ernest
Tomato (Solanum lycopersicum L.) is an important vegetable crop for income and nutrition of smallholder farmers in sub-Saharan Africa. However, it is attacked by many insect pests that cause high economic losses. This review focuses on one insect pest, namely Tuta absoluta (Meyrick, 1917) (Lepidoptera: Gelechiidae). Many studies have shown that chemical pesticides have failed to control tomato leafminer in many parts of the world including America, Europe, Asian and Sub-Saharan Africa, where the pest is impacting significantly the tomato value chains as farmers were unaware of the pest and unprepared to control it. The review has also evaluated current approaches used to manage T. absoluta in different countries and proposes areas for future investment in research for effective and affordable management to prevent further losses caused by T. absoluta in tomato production is SubSaharan Africa.