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Item Fruit consumption and storage practices among rural households in Chamwino district, Dodoma, Tanzania(African Journal of Food Science, 2023-07) Ngawembela, Mwanaisha Assim; Mwanri, Akwilina Wendelin; Chove, Lucy MlipanoFruit consumption is still a challenge in many parts of Africa, and hence micronutrient deficiency continues to be a serious problem in the continent. This study was conducted between December 2017 and May 2018 in Chinoje and Mzula villages in Chamwino district, Dodoma to assess availability of fruit, consumption, storage practices and nutrient content. People responsible for food preparation were interviewed from 345 randomly selected households by using semi-structured and food frequency questionnaires. Multiple logistic regression model was used to determine the relationship between frequency of fruit consumption and household socio-economic features by using SPSS. Laboratory analysis was conducted to determine nutrient content of baobab, which was the most consumed fruit. Analysis of Variance (ANOVA) was used to determine if significant variations existed in the nutritional quality of baobab fruit by using SAS. Only 35% of the households consumed fruit daily, while the majority consumed fruit from one to three days in a week. Monthly income, household size and headship significantly affected fruit consumption at p<0.05. Most of the baobab fruits were stored in polypropylene sacks (77.4%), followed by plastic buckets (3.3%) and others as shelled fruit (18.4%). Significant losses in Vitamin C and total carotenoids were observed in baobab fruits that were stored in sacks. Storage of baobab fruit in plastic bucket is recommended for quality maintenance of nutrients.Item Crop water productivity of an irrigated maize crop in Mkoji sub-catchment of the Great Ruaha River Basin, Tanzania(Elsevier, 2006-09-16) Igbadun, Henry E; Mahoo, Henry F; Salim, Baanda A; Tarimo, Andrew K. P. R.Crop water productivity (CWP) is a quantitative term used to define the relationship between crop produced and the amount of water involved in crop production. It is a useful indicator for quantifying the impact of irrigation scheduling decisions with regard to water management. This paper presents CWP quantified from field experimental data. Three fields were cultivated to maize under irrigation during the 2004 dry season in a traditional irrigation scheme in Tanzania. The maize crop was irrigated at eight different seasonal water application depths: 400, 490, 500, 510, 590, 600, 610 and 700 mm, in two of the three fields, and at five water application depths: 400, 590, 600, 610 and 700 mm in the third field. The variation in seasonal water application depth was achieved by skipping the weekly irrigation once after every other irrigation at some pre-defined stages of the crop growth. CWP were computed in terms of …Item Performance of sorghum varieties under variable rainfall in Central Tanzania(Hindawi, 2017-04) Msongaleli, Barnabas M.; Tumbo, S. D.; Kihupi, N. I; Rwehumbiza, Filbert BRainfall variability has a significant impact on crop production with manifestations in frequent crop failure in semiarid areas. This study used the parameterized APSIM crop model to investigate how rainfall variability may affect yields of improved sorghum varieties based on long-term historical rainfall and projected climate. Analyses of historical rainfall indicate a mix of nonsignificant and significant trends on the onset, cessation, and length of the growing season. The study confirmed that rainfall variability indeed affects yields of improved sorghum varieties. Further analyses of simulated sorghum yields based on seasonal rainfall distribution indicate the concurrence of lower grain yields with the 10-day dry spells during the cropping season. Simulation results for future sorghum response, however, show that impacts of rainfall variability on sorghum will be overridden by temperature increase. We conclude that, in the event where harms imposed by moisture stress in the study area are not abated, even improved sorghum varieties are likely to perform poorly.Item Watershed level baseline assessment in the Mkindo watershed, Wami basin, Tanzania(Stockholm Environment Institute, 2012-07) de Bruin, Annemarieke; Cinderby, Steve; Mbilinyi, Boniface; Mahoo, Henry; Barron, JennieThis report describes the results of a baseline assessment of current livelihood strategies in the Mkindo watershed of the Wami River Basin in Tanzania. The work is part of the IWMI project entitled ‘Agri- cultural Water Management Solutions’ which aims to analyse the impacts and potential of AWM inter- ventions to improve livelihoods at the community, and watershed scales and assess the opportunities, constraints and impacts of the use of AWM technologies. Similar work has been done in two other watersheds, the Nariarlé watershed in Burkina Faso and the Jaldhaka watershed in West Bengal, India. The work in the Mkindo watershed was done during November and December 2009 in cooperation with Soil Water Management Research Group of Sokoine University of Agriculture, Morogoro, Tan- zania. After this baseline assessment different AWM scenarios 1 were analysed .Item Soil nitrogen dynamics and relationships with maize yields in a gliricidia–maize intercrop in Malawi(Kluwer Academic Publishers, 1999-04) Ikerra, Susan T.; Maghembe, Jumanne A.; Smithson, Paul C.; Buresh, Roland J.Many soils of southern Africa are severely N deficient, but inorganic fertilizers are unaffordable for most sub- sistence farmers. Rotations and intercrops of legumes with crops may alleviate N deficiency through biological N 2 fixation and redistribution of subsoil N to the surface. We monitored soil inorganic N dynamics for two seasons in a gliricidia [Gliricidia sepium (Jacq.) Walp.] – maize (Zea mays L.) intercrop in the unimodal rainfall area of southern Malawi. One maize crop per year was grown with or without interplanted gliricidia, in factorial combination with three rates of N (0, 24 or 48 kg N ha −1 ). Application of gliricidia prunings increased (p < 0.001) topsoil (0 to 20 cm) inorganic N at the end of the dry season and during the early rains. Differences between plus and minus gliricidia treatments were less when total inorganic N to 1-m depth was summed. A greater proportion of the total inorganic N to 1-m depth occurred in the topsoil (0 to 20 cm) when gliricidia was present, suggesting that redistribution of subsoil N to the surface accounted for part of the N increase by gliricidia. Gliricidia lowered (p < 0.05) subsoil water content during drier periods. Gliricidia plots accumulated more (p < 0.01) ammonium-N during the dry season. Nitrate-N remained constant during the dry season but rose rapidly in gliricidia plots after the onset of rains. A 2-factor model including preseason inorganic N and anaerobic N mineralization potential accounted for 84% of the variability in maize yields for the two seasons’ data combined. The combination of preseason inorganic N and potential N mineralization appears to provide a good estimate of N supply to maize in systems receiving both organic and inorganic sources of N.Item The ‘Majaluba’ rice production system: A rainwater harvesting ‘Bright Spot’ in Tanzania(2018) Gowing, J; Bunclark, L; Mahoo, H; Kahimba, FThe rainwater harvesting technique under consideration here is an example of intermediate-scale external catchment runoff harvesting. The focus for discussion is on the ‘majaluba’ system which is found in Tanzania and comprises a network of roughly level basins each surrounded by an earth bund. Basins are arranged in the landscape in order to collect local runoff from stony outcrops and grazing lands in upslope areas with cattle tracks often used as conduits. The ‘majaluba’ system is used primarily for the production of rainfed lowland rice. It has spread through autonomous diffusion of knowledge from farmer to farmer since its introduction in the 1930s. The estimated extent of this system is around 600,000 ha which contributes 60% of total rice production in Tanzania. This is a remarkable, but little known, success story, and represents a water harvesting ‘bright spot,’ where sustainable intensification of smallholder agriculture has been achieved at scale.Item Adaptations in water harvesting technologies for enhancing food security and livelihood: A multi-country study in Sub-Saharan Africa(Springer, 2018) Snelder, D; Kahimba, F.C; Korodjouma, O; Abebe, A; Oughton, E; Bunclark, L; Lasage, RThe objective of this paper was to examine farmer-directed technology adaptation of selected water harvesting technologies (WHTs) in order to enhance their potential contribution to food security and livelihood improvement in sub-Saharan Africa. The selected WHTs included micro- and meso-scale reservoirs that store water in the soil (in situ) or in a reservoir, respectively: household ponds in Ethiopia, ndiva systems in Tanzania and combinations of mechanized zaï, grass strips and bunds in Burkina Faso. The impact of non-adapted WHTs was below expectation. Although WHTs improved yields, most families were unable to meet their (nutritional) food needs every year and experienced limited or no long-term effects on sustainable livelihood. The lining of household ponds and conveyance canals with durable materials gave promising results, yet needs economic consideration; a minimum investment may form a barrier particularly to resource-poor farmers. Incorporation of the location-specific nature of farming and livelihoods into WHT interventions is recommended, along with incentive measures to support farmers including the provision of access to credits and inputs for agricultural production.Item Comparison of silicon status in rice grown under the system of rice intensification and flooding regime in Mkindo Irrigation Scheme, Morogoro, Tanzania(TAJAS, 2020) Gowele, G. E.; Mahoo, H. F.; Kahimba, Frederick C.Silicon (Si) is the second most abundant element available in the earth's crust, and is considered as a benefcial element for crop growth especially rice. A study was conducted in Mkindo irrigation scheme, Mvomero District, Morogoro, Tanzania to assess the Silicon status in rice grown under the System of Rice Intensifcation and continuous flooding at various growth stages. The experiment was laid out in a randomized complete block design (RCBD) with two treatments which were two water application regimes: T1 was alternate wetting and drying using SRI technology and T2 was continuous flooding. The treatments were replicated three times and the rice variety used was SARO 5 (TXD 306). The experiment was conducted in two seasons from October 2019 to January 2020 and from March 2020 to June 2020. Si status in rice seeds and grains as well as rice plant leaves at various growth stages were evaluated according to elemental analysis based on Energy Dispersive X- Ray Fluorescence and results were analyzed using GENSTAT software. Si content in rice seeds observed prior to the experiment was 6.76%. Si content in rice grains was gradually increasing during reproductive stage and later drops during harvest. Si content in rice plant leaves increased signifcantly from vegetative to ripening stage whereby the highest Si content was recorded in T 1 (12.37%) while T2 recorded the lowest value (10.15%). It was concluded that, the alternate wetting and drying feld conditions enhances adequate uptake of Si compared to continuous flooding practices.Item Evaluation of the performance of CORDEX regional climate models in simulating present climate conditions of Tanzania(ResearchGate, 2016-06) Luhunga, Philbert; Botai, Joel; Kahimba, Frederick C.Regional climate models (RCMs) are widely used in regional assessment of climate change impacts. However, the reliability of individual models needs to be assessed before using their output for impact assessment. In this study, we evaluate the performance of RCMs from the Coordinated Regional Climate Downscaling Experiment program (CORDEX) to simulate minimum air temperature (TN), maximum air temperature (TX) and rainfall over Tanzania. Output from four RCMs driven by boundary conditions from three General Circulation Models (GCMs) and ERA-Interim data are evaluated against observed data from 22 weather stations. The evaluation is based on determining how well the RCMs reproduce climatological trends, interannual, and annual cycles of TN, TX and rainfall. Statistical measures of model performance that include the bias, root mean square error, correlation and trend analysis are used. It is found that RCMs capture the annual cycle of TN, TX and rainfall well, however underestimate and overestimate the amount of rainfall in March–April–May (MAM) and October–November–December (OND) seasons respectively. Most RCMs reproduce interannual variations of TN, TX and rainfall. The source of uncertainties can be analysed when the same RCM is driven by different GCMs and different RCMs driven by same GCM simulate TN, TX and rainfall differently. It is found that the biases and errors from the RCMs and driving GCMs contribute roughly equally. Overall, the evaluation finds reasonable (although variable) model skill in representing mean climate, interannual variability and temperature trends, suggesting the potential use of CORDEX RCMs in simulating TN, TX and rainfall over Tanzania.Item Estimating conveyance efficiency and maize productivity of traditional irrigation systems in USA river catchment, Tanzania(Hindawi, 2020-07) Haymale, Humuri K.; Njau, Karoli N.; Kahimba, Frederick C.Estimating the conveyance efficiency of traditional irrigation schemes systems is very important. It is because of understanding the volume of water lost along with the transportation facility, enhancing water usage and productivity, hence making better decisions about the utilization of water resources. (e objective of the study was to determine water abstraction permit compliances and estimate conveyance efficiency and crop and water productivity of traditional irrigation systems in northern Tanzania. (e task involved measurement of irrigation water flows to determine the amount of water abstraction, inflow (head) and outflow (tail) between the canals to determine the conveyance efficiency of the main, secondary, and tertiary canals of the traditional irrigation systems. Moreover, water and yield obtained at the farm level were determined. Results indicate that approximately 72% of water transported reaches the destined farm which produced maize (Zea mays L) yields of 1054.5 kg/ha, 892.4 kg/ha, and 875.156 kg/ha at downstream, midstream, and upstream which equals 0.41 kg/m3, 0.15 kg/m3, and 0.09 kg/m3, respectively, while about 28% of water is lost along the canals through evaporation, seepage, and deep percolation and overtopping. Consequently, water measured at furrow intakes in total was 3, 500 L/s, equal to 23% more than the permitted amount of 2856.14 L/s at Usa River Catchment. Interventions to minimize water losses starting at the furrow’s intakes are urgently required in the current trend of the increasing demand for water resources for food production and schemes performance. Subsequently, more effective conveyance technologies and water management strategies other than canal lining are required.Item Effect of Fertilizer Micro-Dose and Moisture Management Practices on Agronomic and Economic Performances of Groundnut in Semi- Arid Areas(ELIXIR, 2019-05) Chilagane, E.A; Saidia, P.S; Kahimba, F.C; Swai, E; Rweyemamu, C.LLow soil fertility and drought condition are main crop production challenges that threatening food security in semi-arid areas. Use of fertilizer at micro dose rates together with in-situ rainwater harvesting using infiltration pits (IP) or tied ridges (TR) are lowinput strategies to cope with these challenges. This research was conducted to investigate effects of integrating fertilizer micro dose rates and in-situ rainwater harvesting using IP and TR on groundnut yield and its household profitability to Tanzania smallholder farming groups. Field experiments were conducted from 2015/2016 to 2016/2017 cropping seasons. Infiltration pits and tied ridges increased groundnut yield significantly by 20.2 to 32.6 % and 34.2 to 46.6% respectively over flat cultivation. Fertilizer micro dose at 50% of recommended rate significantly increased yield by 50.8 to 64.7 % over zero application. Integration of TR with fertilizer at RR resulted into highest groundnut yield ranged from 1,034 to 1,096 kg/ha and highest NP ranged from 1,027 to 1,081 USD/ha. The integrations of TR and fertilizer micro dose at 50% of recommended had significant higher yield ranged from 748 to 1,086 kg/ha and higher NP ranging from 405 to 662 USD/ha compared to famer practice. The integrations of micro dose rate of 50% of recommended rate and tied ridges is therefore recommended to small holder’s famers located in semi dry areas of central Tanzania. This will enable farmers to achieve highly agronomic and economic performances compared to farmer practices.Item Crop Upgrading Strategies and Modelling for Rainfed Cereals in a Semi-Arid Climate—A Review(Water, 2018-03) Silungwe, F.R; Graef, F; Bellingrath-Kimura, S.D; Tumbo, S.D; Kahimba, F.C; Lana, M.ASpatiotemporal rainfall variability and low soil fertility are the primary crop production challenges facing poor farmers in semi-arid environments. However, there are few solutions for addressing these challenges. The literature provides several crop upgrading strategies (UPS) for improving crop yields, and biophysical models are used to simulate these strategies. However, the suitability of UPS is limited by systemization of their areas of application and the need to cope with the challenges faced by poor farmers. In this study, we reviewed 187 papers from peer-reviewed journals, conferences and reports that discuss UPS suitable for cereals and biophysical models used to assist in the selection of UPS in semi-arid areas. We found that four UPS were the most suitable, namely tied ridges, microdose fertilization, varying sowing dates, and field scattering. The DSSAT, APSIM and AquaCrop models adequately simulate these UPS. This work provides a systemization of crop UPS and models in semi-arid areas that can be applied by scientists and pItem Influence of Transplanting Age on Paddy Yield under the System of Rice Intensification(Agricultural Sciences, 2016-07) Reuben, P; Kahimba, F.C; Katambara, Z; Mahoo, H.F; Mbungu, W; Mhenga, F; Nyarubamba, A; Maugo, MAgronomic practices such as transplanting age, plant spacing, and water application regimes in irrigated paddy production can have a significant impact towards the performance in rice growth and yield. A study was conducted to investigate the optimum transplanting age for maximum rice productivity under the systems of rice intensification (SRI) technology. The study treatments adopted were three representing 8, 12 and 15 days old seedlings replicated 3 times each. The experiment was set in randomized complete block design (RCBD) and transplanted at spacing 25 cm × 25 cm between rice hills. The rice variety tested was TXD 306 Super SARO, which was recommended by the ministry of Agriculture in Tanzania. Data was collected throughout the growing season in two mixed short rains and dry season of September 2013/2014 and September 2014/2015. Data collected included biomass at vegetative, flowering and harvesting stages, total number of tillers per hill, number of productive tillers per hill, number of grains per panicle and rice grain yield at the end of the season. Data was analyzed using SAS software version 9.1. The results suggested that transplanting at younger age of 8 to 12 days was recommended for Mkindo area in Mvomero Distirct, and other areas with similar soil conditions and agro ecological characteristics.Item Modelling rainfed pearl millet yield sensitivity to abiotic stresses in semi-arid central Tanzania, Eastern Africa(Sustainability, 2019-08) Silungwe, F.R; Graef, F; Bellingrath-Kimura, S.D; Chilagane, E; Tumbo, S.D; Kahimba, F.C; Lana, M.ADrought and heat-tolerant crops, such as Pearl millet (Pennisetum glaucum), are priority crops for fighting hunger in semi-arid regions. Assessing its performance under future climate scenarios is critical for determining its resilience and sustainability. Field experiments were conducted over two consecutive seasons (2015/2016 and 2016/2017) to determine the yield responses of the crop (pearl millet variety “Okoa”) to microdose fertilizer application in a semi-arid region of Tanzania. Data from the experiment were used to calibrate and validate the DSSAT model (CERES Millet). Subsequently, the model evaluated synthetic climate change scenarios for temperature increments and precipitation changes based on historic observations (2010–2018). Temperature increases of +0.5 to +3.0 ◦C (from baseline), under non-fertilized (NF) and fertilizer microdose (MD) conditions were used to evaluate nine planting dates of pearl millet from early (5 December) to late planting (25 February), based on increments of 10 days. The planting date with the highest yields was subjected to 49 synthetic scenarios of climate change for temperature increments and precipitation changes (of −30% up to +30% from baseline) to simulate yield responses. Results show that the model reproduced the phenology and yield, indicating a very good performance. Model simulations indicate that temperature increases negatively affected yields for all planting dates under NF and MD. Early and late planting windows were more negatively affected than the normal planting window, implying that temperature increases reduced the length of effective planting window for achieving high yields in both NF and MD. Farmers must adjust their planting timing, while the timely availability of seeds and fertilizer is critical. Precipitation increases had a positive effect on yields under all tested temperature increments, but Okoa cultivar only has steady yield increases up to a maximum of 1.5 ◦C, beyond which yields decline. This informs the need for further breeding or testing of other cultivars that are more heat tolerant. However, under MD, the temperature increments and precipitation change scenarios are higher than under NF, indicating a high potential of yield improvement under MD, especially with precipitation increases. Further investigation should focus on other cropping strategies such as the use of in-field rainwater harvesting and heat-tolerant cultivars to mitigate the effects of temperature increase and change in precipitation on pearl millet yield.Item The management strategies of pearl millet farmers to cope with seasonal rainfall variability in a semi-arid agroclimate(Agronomy, 2019-07) Silungwe, F.R; Graef, F; Bellingrath-Kimura, S.D; Tumbo, S.D; Kahimba, F.C; Lana, M.ARainfed agriculture constitutes around 80% of the world’s agricultural land, achieving the lowest on-farm crop yields and greatest on-farm water losses. Much of this land is in developing countries, including sub-Saharan Africa (SSA), where hunger is chronic. The primary constraint of rainfed agriculture—frequently experienced in SSA—is water scarcity, heightened by the unpredictability of season onset, erratic rainfall, as well as the inability of farmers to provide adequate soil and crop management. Farmers react differently to constraints, making a variety of choices—including the timing of planting, type of land cultivation, fertilization, and scattered fields, among many others. Limited information is available on the combined effects of these strategies for improving crop yield and water use efficiency (WUE). An experiment was co-conducted with farmers over four consecutive rainy seasons (2014–2018) in Tanzania, to evaluate these strategies for single and joint effects in improving yield and WUE on rainfed pearl millet (Pennisetum glaucum (L.) R.Br.). The treatments used were flat cultivation both without and with microdosing, as well as tied ridging without and with microdose interaction, with different planting dates depending on farmers’ decisions. Results show that farmers react differently to the early, normal, or late onset of the rainy season, and cumulative rainfall during its onset, which affects their decisions regarding planting dates, yield, and WUE. Microdose fertilization increases both the yield and WUE of pearl millet significantly, with greater effects obtained using tied ridging compared to flat cultivation. For low-income smallholder farmers in a semi-arid agroclimate, using tied ridging with microdosing during early planting is an effective response to spatiotemporal rainfall variability and poor soils.Item Soil moisture management and fertilizer micro-dosing on yield and land utilization efficiency of inter-cropping maize-pigeon-pea in sub humid Tanzania(Elsevier, 2019-07) Saidia, P.S; Rweyemamu, C.L; Semoka, J.M.R; Kimaro, A.A; Germer, J; Asch, F; Kahimba, F.C; Graef, F; Lagweni, P.PPrincipally caused by soil water stress and declining soil fertility, low crop productivity results in both food and income insecurity. The effects of nitrogen and phosphorus fertilizer micro-dosing with inter-row rainwater harvesting practices for maize and pigeon-pea inter-cropping on yield and land use efciency are inadequately documented in sub humid tropics. A feld experiment on sandy loam soils in sub humid conditions using a splitsplit plot design was conducted. Plots used in situ rainwater harvesting practices of tied ridges, open ridges, and flat cultivation. Sub-plots were sole maize, sole pigeon-pea, and 1:1 maize-pigeon pea inter-cropping. The subsub plots were control, fertilizer (N and P) application at the micro-dose level, and recommended rates. Tied ridges signifcantly (p < 0.001) conserved more soil moisture than flat cultivation at 30 cm depth after ten days of rainfall. Ridges increased maize yield by 0.3 t ha−1 over flat cultivation. Fertilizer application signifcantly (p < 0.001) increased maize yield by 1.12 t ha−1 with micro-dosing and by 1.60 t ha−1 with recommended rates over the control. Combining tied ridges and fertilizer signifcantly (p < 0.040) increased maize yield by 132–156% compared to flat cultivation without fertilizer. Reflecting a land equivalent ratio, land use efciency was 67–122% higher in inter-cropping than sole crop. Tied ridges conserved more soil moisture than flat cultivation, enhancing fertilizer use efciency that improved crop yields and land equivalent ratio under intercropping. This strategy could increase food availability and income generation under smallholder farming systems in sub-humid tropic areas.Item Analysis of Intra and Interseasonal Rainfall Variability and Its Effects on Pearl Millet Yield in a Semiarid Agroclimate: Significance of Scattered Fields and Tied Ridges(Water, 2019-03) Silungwe, F.R; Graef, F; Bellingrath-Kimura, S.D; Tumbo, S.D; Kahimba, F.C; Lana, M.AEstablishing food security in sub-Saharan African countries requires a comprehensive and high resolution understanding of the driving factors of crop production. Poor soil and adverse climate conditions are among the major drivers of poor regional crop production. Drought and rainfall variability challenges are not fully being addressed by rainfed producers in semiarid areas. In this study, we analysed the spatiotemporal rainfall variability (STRV) and its effects on pearl millet yield using two seasons of data collected from 38 rain gauge stations scattered randomly in farm plots within a 1500 ha area of semiarid central Tanzania. The STRV effects on pearl millet yield under flat and tied ridge management were analysed. Our results show that seasonal rainfall can vary significantly for neighboring fields at distances of less than 200 m, which impacts yield. The STRV for daily rainfall was found to be more critical than for total seasonal rainfall amounts. Scattering fields can help farmers avoid total harvest loss by obtaining at least some yield from the areas that received adequate rain. The use of tied ridges is recommended to conserve soil moisture and improve yields more than flat cultivation in semiarid areas.Item Nitrogen and Phosphorus Fertilizer Micro-doses on Maize and Its Effect on P-foriability: An evidence from Sub-humid Farming Systems, Tanzania(ournal of Economics, Management and Trade, 2018) Saidia, P.S; Graef, F; Rweyemamu, C.L; Kahimba, F.C; Semoka, J.M.R; Kimaro, A.A; Mwinuka, L; Mutabazi, K.D; Sieber, SDespite a high productive potential for many best bet agricultural technologies, there is a low rate of adoption from farmers. Recommendations of improved technologies such as fertilizer use based on agronomic data without economic analysis contributes to this low adoption rate. The purpose of this study was to evaluate the profitability of selected fertilizer types and rates in maize production in a sub-humid farming system. A field experiment was conducted to investigate costs and revenue of fertilizer types and rates applied on maize farms using a split-plot layout under randomized complete block design. The phosphate fertilizers trialed were local Minjingu Mazao (MM), diammonium phosphate (DAP) and triple super phosphate (TSP), urea was used to supply nitrogen. Fertilizer rates were micro-doses at 12.5%, 25%, 50% and 75% compared to control and recommended rates. Local MM at 75% micro-dosing produced the highest net benefit 3.0 – 3.5 million Tanzanian Shillings per hectare (TZS/ha) followed by 2.7 – 2.9 million TZS/ha from TSP at recommended rates and DAP at a 75% micro-dose rate under subsistence farming. Micro-dosing fertilizer at 25% and 50% produced the highest benefit-cost ratio under both commercial and subsistence farming conditions. Micro-dosing at a rate of 12.5% was more profitable than the control rate and farm profitability increased towards 25% and 50%, thereafter decreasing as application approached the recommended rate. Adoption of micro-dosing fertilizer at 12.5% could be an entry point to fertilizer use and to later be advanced to 25% and 50% micro-dosing rates which are more profitable under smallholder farming systems in sub-humid tropics.Item Assessment of upgrading strategies to improve regional food systems in Tanzania: Food processing, waste management and bioenergy, and income generation(SAGE, 2015) Graef, F; Schneider, I; Fasse, A; Germer, J.U; Gevorgyan, E; Haule, F; Hoffmann, H; Kahimba, F.C; Kashaga, L; Kashaga, L; Lambert, C; Lana, M; Mahoo, H.F; Makoko, B; Mbaga, S.H; Mmbughu, A; Mmbughu, S; Mrosso, L; Mutabazi, K.D; Mwinuka, L; Ngazi, H; Nkonya, E; Said, S; Schaffert, A; Schäfer, M.P; Schindler, J; Sieber, S; Swamila, M; Welp, H.M; William, L; Yustas, Y.MFood security is one of the main goals of rural poor people. To enhance food security in this context, participatory action research can help to ensure sustained success while considering entire food value chains (FVC). This paper assesses the feasibility and potential success of upgrading strategies (UPS) as well as their assessment criteria as developed by German and Tanzanian agricultural scientists. The results form part of a larger participatory research project conducted in two climatically representative regions of Tanzania: semi-arid Dodoma and subhumid Morogoro. This paper presents the findings with respect to food processing, waste management and bioenergy, along with income generation and market participation. Assessments on other components of the FVC, including natural resource management, crop production and consumption, are reported by Graef et al (2015). The assessments for food processing revealed preferences for preservation techniques, oil extraction processes and food storage devices for the semi-arid region. In contrast, in the subhumid region, the experts favoured food storage devices and preservation techniques. Assessments of waste management and bioenergy UPS for both regions indicated the importance of animal feed from crop residues, crop residues as mulch and compost from food waste, although with somewhat different priorities. Assessments on income generation and markets in both regions revealed preferences for savings and credit cooperatives and communication techniques, but also indicated that warehouse receipt systems and guarantee systems had a high impact. Assessments differed between the two different climatic regions, and to some extent also between the nationality of experts and their gender. The authors therefore attach importance to integrating different South–North and female–male awareness in assessments among scientists. Moreover, local and/or regional stakeholders and experts should be involved in developing site-adapted UPS for enhancing FVCs.Item Optimizing Plant Spacing under the Systems of Rice Intensification (SRI)(Scientific Research Publishing Inc., 2016) Reuben, P; Kahimba, F.C; Katambara, Z; Mahoo, H.F; Mbungu, W; Mhenga, F; Nyarubamba, A; Maugo, MOptimum plant spacing is among key agronomic parameters that influence crop growth performance and crop yield. A study was conducted to investigate the optimum rice transplanting spacing under the Systems of Rice Intensification (SRI) practice in Tanzania. The study composed of five treatments of rice transplanting spacing namely 1) 15 cm × 15 cm (T1); 2) 20 cm × 20 cm (T2); 3) 25 cm × 25 cm (T3); 4) 30 cm × 30 cm (T4); and 5) 35 cm × 35 cm (T5). The experiment was set in a Randomized Complete Block Design (RCBD) and transplanted with uniform age of 12 days old seedlings in all treatments. The rice variety tested was TXD 306 Super SARO which was recommended by the Ministry of Agriculture for flooded rice in central and eastern Tanzania. Data was collected throughout the two growing seasons (Masika and Vuli) of 2013 and 2014. Data collected include biomass at vegetative, flowering and harvesting stages, total number of tillers per hill, number of productive tillers per hill, number of grains per panicle and rice grain yield at the end of the season. Data was analyzed using SAS software version 9.1. Results have shown that transplanting spacing of 25 cm × 25 cm, 30 cm × 30 cm and 35 cm × 35 cm has significantly performed better than rice transplanted at 15 cm × 15 cm and 20 cm × 20 cm. For the higher performing treatments, 25 cm × 25 cm has performed much higher than the rest. It is therefore recommended that for rice variety TXD 306 Super SARO under SRI practice in areas with soil conditions similar to Mkindo area in Morogoro Region, the optimum transplanting spacing that gives maximum yield is 25 × 25 cm.