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    Exploring farmers’ perception, knowledge, and management techniques of salt-affected soils to enhance rice production on small land holdings in Tanzania
    (Taylor&Francis, 2022-10) Omar, M. M; Shitindi, M. J.; Massawe, B. H. J; Fue, K. G; Pedersen, O.; Meliyo, J. L.
    Salt-affected soils among the key constraints to land productivity in irrigated rice schemes, posing a decline in grain yield. This study was conducted to explore the farmers’ perception, knowledge, and management practices of salt- affected soils in selected rice irrigation schemes of the representative districts in Tanzania. Whereas salt-affected soils were perceived as one of the constraints in the studied irrigation schemes, the extent of coverage and the severity of the effect are rarely documented. Therefore, the primary hypothesis of this study is that salt- affected soils could have an effect on rice production across irrigation schemes; and that farmers differ in perception, knowledge, and coping mechanisms. The Participatory Rural Appraisal (PRA) approach was employed to explore the farmers’ information from Mbarali, Iringa, Same, and Moshi districts, whereby 323 rice- growing farmers were interviewed using semi-structured questionnaires. Moreover, 120 farmers were involved in focus group discussions and 24 key informants. Our
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    Decision Support System for Runoff Water Harvesting and Irrigation
    (Science Domain, 2016) Singa, Darwin Dodoma; Tumbo, Siza Donald; Fatael, Mahoo Henry; Filbert, Rwehumbiza; Maxon, Lowole
    Despite the prevailing versatility of agro-hydrological Decision Support Systems (DSS) in the agricultural sector, a number of associated deficiencies do exist. The deficiencies are due to lack of synchronization of runoff affecting rainfall, catchment factors, reservoir capacity and irrigation field area in the face of recurring droughts and dry spells in several areas of Sub-Saharan Africa (SSA). The study focused on designing and validating a Decision Support System, by adding water reservoir and irrigation sub-routines to an Agro-hydrological Nedbor Afstromnings Model (NAM) to assist in screening best-bet options for either crop field area or reservoir size using a case study of common beans (Phaseolus vulgaris, L.) at Ukwe Area in Malawi. Microsoft excel spreadsheet (MS excel) was used to compute cumulative runoff inflows into the dam, seasonal open surface water storage, water losses and withdrawal and reservoir water available for the bean crop. Computer simulation using soil, vegetation and topographical characteristics, and crop water requirements revealed proportion of catchment to irrigation command area of 10:1 with bean water productivity of 0.7 g/l (0.7 kg/m3 ), indicating low water demand. The NAM simulated values were in agreement with calculated ones. Post-DSS gross margin analysis indicated that 2.42 times more crop returns were obtained from irrigated than rain-fed bean crops despite additional costs associated with reservoir maintenance and irrigation operations. The DSS is, hence, found potential for users in drought prone Sub-Saharan African countries such as Malawi.
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    Effect of NPK and Minjingu mazao fertilizers on the performance of Sweetpepper in Morogoro, Tanzania
    (Direct Research Journals Publisher, 2014) Rwiza, Alex Audax; Kisetu, Eliakira
    This study assessed the effect of NPK (23:10:5) and Minjingu mazao (10:20:15) fertilizers on the performance of sweetpepper (Capsicum annuum L.) cv. California Wonder. The plant growth parameters collected were: plant height, number of leaves per plant, stem girth, and number of branches per plant. The parameters related to yield were fruit grade, fruit shape index (FSI), number of fruits per plant, weight of fruits per plant, and fruit yield. The NPK fertilizer resulted into significantly (P=0.03) highest average fruit yield (25 t ha-1). Minjingu mazao fertilizer recorded fruit yield (15.6 t ha-1) which was also significantly higher (P= 0.03) than the corresponding control. Fruit yields increase due to NPK fertilizer as opposed to the control and Minjingu mazao fertilizer were 166% and 66%, respectively. This was the same as 66% increase in fruit yield when Minjingu mazao fertilizer was used compared with the control. The Pearson matrix correlation indicated that the fruits length, fruits grade, weight of individual fruits and fruit yield had the strongest relationship (r ≥ 0.90***; P<0.001).
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    Modeling potential rain-fed maize productivity and yield gaps in the Wami river sub-basin, Tanzania
    (Taylor And Francis Journals, 2015) Mourice, Sixbert Kajumula; Tumbo, Siza Donald; Amuri, Nyambilila; Rweyemamu, Cornell Lawrence
    The cause for low maize yields in rain-fed production systems is usually associated with water stress due to perceived suboptimal seasonal precipitation. A modeling study using Agricultural Model Intercomparison and Improvement Project modeling framework was conducted to determine the magnitude of rain-fed potential yield and yield gap of maize in the Wami River sub-basin, Tanzania. Primary and secondary data on soils, weather, management, and crop yields and cultivars were used. Data matrix search technique was used to calibrate CERES-Maize Crop System model against reported yield for each of 168 farms involved in this study. Then the individual farms’ simulated yields, actual reported yields, and the resultant yield gaps were aggregated into ward-level averages. Model calibration was robust as there was a very close agreement between reported and simulated yield (R2 = 0.9). Actual yields reported from farm survey ranged from 50 kg ha−1 to 3600 kg ha−1 with an average of 860 kg ha−1 . Simulated rain-fed potential yield was between 2073 kg ha−1 and 5443 kg ha−1 and a mean of 4033 kg ha−1 . It is apparent therefore that there exists a wide maize yield gap of 79% with current management under rain-fed conditions. This suggests that there is a large scope of improving maize yields under rain-fed conditions. Narrowing the yield gaps would require an intensive soil fertility improvement in the study area.
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    Potential of soil fertility management to improve essential mineral nutrient concentrations in vegetables in Dodoma and Kilombero, Tanzania
    (Scientific Research Publishing Inc., 2017) Amuri, Nyambilila A; Mhoro, Lydia; Mwasyika, Tumaini; Semu, Ernest
    Collective efforts to fight mineral nutrient malnutrition in humans require consideration of soil fertility management practices (SFMP) in vegetable pro duction. This study aimed at establishing the relationship between SFMP and vegetable nutrient concentration for human health in farming systems of Tanzania. Soil and vegetable samples collected from vegetable growing areas in Kilombero and Dodoma were analyzed for chemical properties and mineral nutrient concentration. Descriptive statistics, analysis of variance and correla tion analysis were employed. The results showed that soil pH in Kilombero ranged from 6.04 to 6.8 and in Dodoma ranged from 6.23 to 8.58. The organic C was low, ranged from 0.10% to 1.87%. All soils studied had sufficient Zn (0.45 to 29.3 mg/kg), Cu (0.71 to 3.23 mg/kg), Fe (3.70 to 171.7 mg/kg) and Mn (2.84 to 41.38 mg/kg). Zinc concentration in all vegetables ranged from 12.57 to 134.54 mg/kg, 14% of vegetables had low Zn (<20 mg/kg) for human health. The Cu concentration in vegetables ranged from 0.07 to 52.37 mg/kg, and vegetables from Kilombero had very low Cu (<0.10 mg/kg) for plant and human nutrition. Vegetable Fe and Mn concentration ranged from 152.95 to 1780 mg/kg and 35.10 to 321.82 mg/kg, respectively. The SFMP used did not affect mineral micronutrients concentration in vegetables, but affected soil Zn, Cu, Fe and Mn concentrations. Soil pH, Zn, and CEC correlated with vegeta ble Cu, K, Mg, Zn, P and Fe concentrations, and differed among soils. There fore, soil properties differed with SFMP, and both determined mineral con centrations in vegetables for human health.
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    Challenges facing effective use of bat guano as organic fertilizer in crop production: a review
    (International Journal of Engineering and Applied Sciences, 2021) Marwa, Ernest Melkiory; Andrew, Twisege; Hatibu, Asha Ally
    Bat guano is excrements of bats and it is commonly used in agriculture as a soil amendment and sometimes as a pesticide in organic farming. Small-scale farmers nearby guano deposits use it for indoor and outdoor plants as well as for hydroponic crop production. Guano in soils acts as a source of carbon (C) and energy to drive microbial activities as well as a precursor to soil organic matter fractions. With all these benefits, bat guano should be used in crop production with some precautions. Chemical composition and properties of bat guano are not fixed and are changing with time depending on the maturity, reaction with the country rock and bat diet. The pH of guano changes from alkaline to strongly acid with maturity. Similarly, guano loses some essential plant nutrients on decomposition and sometimes acquires potentially toxic elements as it reacts with the host rocks. Amounts added to the soil also vary with maturity and composition of guano. Thus, utilization of bat guano as organic fertilizer requires a thorough and regular characterization at the time of using it as soil amendment for crop production
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    Pedological characterization and soil fertility assessment of the selected rice irrigation schemes, Tanzania
    (Frontiers, 2023) Marzouk, Said H; Tindwa, Hamis J; Massawe, Boniface H. J; Amur, Nyambilila A; Semoka, Johnson M
    Rice (Oryza sativa L.) is the second cereal food crop grown in Tanzania after maize (Zea mays L.) and covers approximately 18% of the agricultural land. Soil degradation due to intensive cultivation along with low organic matter input and nutrient imbalance has led to a decline in rice crop yields. This study was conducted to characterize, classify, and assess the fertility status of soils in two rice irrigation schemes of Morogoro region in Tanzania. The data obtained through this study will contribute significantly to land use planning and will facilitate the transfer of agro-technology and other development of the regions with similar ecological conditions. The studied pedons were named MKU-P1 and MKD-P1 for Mkula and Mkindo irrigation schemes, respectively. A total of seven composite soil samples (0–20 cm) were collected for soil fertility assessments. Landform, soil morphological features, parent material, natural vegetation, drainage, erosion, and laboratory data were used to classify the soils in their respective order as per the United States Department of Agriculture (USDA) Soil Taxonomy and the World Reference Base (WRB) soil classification systems. Results showed that the pedons were sandy clay loam in the topsoil and sandy clay to clay in the subsoil; soil reaction ranged from medium acid (pH 5.7) to strongly alkaline (pH 8.6). The topsoil and subsoil nutrients of the studied pedons including available K+, total N, soil organic matter, and organic carbon are low. Based on the USDA Soil Taxonomy, MKU-P1 is classified as Inceptisols cumulic humaquepts and MKD-P1 as Vertisols Fluvaquentic endoaquerts corresponding to Subaquatic fluvisols (loamic, oxyaquic) and Irragric vertisols (gleyic) in the WRB, respectively. The pedons were ranked as suitable for rice production. However, the chemical fertility of the soil is ranked as low fertile associated with deficient in total N; available P, K+, and Ca2+ with excessive iron and manganese; and likely to pose toxicity to crops. The application of organic and mineral amendments in recommended rates and timing for N and P is therefore essential to increase the nutrient content of these soils and minimize losses. Salinity in the subsurface pedon MKD-P1 needs to be taken into future consideration.
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    Lowering nitrogen rates under the system of rice intensification enhanced rice productivity and nitrogen use efficiency in irrigated lowland rice
    (cell Press, 2022) Mboyerwa, Primitiva Andrea; Kibret, Kibebew; Mtakwa, Peter; Aschalew, Abebe
    Among the essential plant nutrients, nitrogen (N) is the most important and universally deficient in rice cropping systems worldwide. Despite different practices available for improvement of N management, nitrogen use effi- ciency (NUE) is still very low in rice, particularly under conventional management practices. This study was conducted to assess the effect of two crop management practices including the system of rice intensification (SRI) versus conventional management practices (CP) with four N application levels (60, 90, 120, and 150 kg N ha 1 ) and absolute control (i.e., without N application) on rice growth, grain yield, and NUE. Experiments were established in split-plot randomized complete block design in three replicates. Crop management practices and N levels were treated as the main effect of main-plots and sub-plots, respectively with replicate blocks treated as random factors. Results indicated that deploying of SRI increased rice grain yield by 17.5 and 52.4% during wet and dry seasons, respectively compared with the CP. Rice grain yield was significantly (p < 0.05) higher in SRI than in CP at all levels of N application compared. The application of N at 120 and 60 kg ha 1 resulted in the increase in rice grain yields by 49 and 46.5%, respectively, relative to the absolute control during wet and dry seasons. Nitrogen application had a significant effect (p < 0.05) on agronomic nitrogen use efficiency (ANUE) and partial factor productivity (PFP). Results also indicated that agronomic nitrogen use efficiency (ANUE) was higher (27.2 kg grain kg 1 N) during the wet season with an application of 60 kg N ha 1 . Furthermore, higher ANUE (23.8 kg grain kg 1 N) was recorded during dry season with an application of 90 kg N ha 1 . The significant (p < 0.05) interaction effects of treatments were recorded on PFP between SRI and 60 kg N ha 1 during the wet (116.7 kg grain kg 1 N) and dry (105.8 kg grain kg 1 N) seasons. This study revealed that ANUE and PFP decreased with N application at the levels of 120 and 150 kg N ha 1 under SRI and CP during the two cropping seasons. The findings of the present study provide potential information that rice grain yield and higher NUE could be achieved at low N inputs under SRI, and thus reducing costs resulted from fertilizer inputs without compromising other environmental benefits.
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    Soils and land evaluation of part of the sokoine university of agriculture farm (Tanzania) for some crops under rainfed conditions
    (The Center for African Area Studies, Kyoto University, 1994) Kaaya, Abel K; Mrema, Jerome P; Msanya, Balthazar M
    A detailed soil survey of about 420 ha of the central part of the Sokoine Uni versity of Agriculture farm was carried out for soil characterization. laboratory physico chemical characterization, soil classification and land suitability evaluation of the area with respect to maize (Zea mays), sorghum (Sorghum bic%r), paddy rice (Oryza sativa) and field beans (Phaseo/us vulgaris); all under rainfed conditions. The soils were mapped at 1/10,000 scale besed on slope, soil drainage, topsoil texture and effective soil depth and five mapping units were identified. Land suitability evaluation indicated that none of the identi fied mapping units was highly suitable for the above listed crops
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    Soil property and soybean yield trends in response to alternative wheat residue management practices in a wheat-soybean, double-crop production system in eastern Arkansas
    (Electronic Journal of Integrative Biosciences, 2008) Amuri, Nyambilila; Brye, Kristofor R; Gbur, Edward E; Popp, Jennie; Chen, Pengyin
    Growing concerns over the long-term sustainability of agricultural systems require investigation of agricultural management practices that may improve and sustain soil quality and crop productivity over time. Over 20% of the soybean [Glycine max (L.) Merr.] area in the highly productive Mississippi River Delta region of the mid southern United States is in a double-crop rotation with wheat [Triticum aestivum (L.)]. Currently, much of the resulting wheat residue is managed by burning followed by conventional tillage, but this combination may not be environmentally sustainable. Therefore, the objective of this study was to determine the long term effects of tillage [conventional (CT) and no-tillage (NT)], wheat-residue burning (burn and no burn), wheat-residue level (low and high, achieved with differential N fertilization), and irrigation (irrigated and dry-land) on soybean yield, net economic returns, and soil properties in the top 10 cm of a wheat -soybean, double-crop production system. A field experiment was conducted from 2001 through 2007 in the Mississippi River Delta region of eastern Arkansas on a Calloway silt loam (fine silty, mixed, active, thermic Glossaquic Fraglossudalf). Soil bulk density increased in both CT and NT during the first three years, but at a greater rate under NT (0.12 g cm-3 yr-1) than CT (0.08 g cm-3 yr-1), followed by a decline at a similar rate in both tillage treatments. Soil pH and Mehlich-3 extractable soil Ca and Mg contents increased, while electrical conductivity decreased linearly over time when all treatments were combined. Soil organic matter (SOM) increased over time in all treatment combinations. Total C (TC) increased at a greater rate in the no burn (0.08 kg C m-2 yr-1) and high-residue level (0.07 kg C m-2 yr-1) than in the burn (0.05 kg C m-2 yr-1) and low-residue-level (0.05 kg C m-2 yr-1) treatments. Extractable soil P content declined linearly over time at greater rate under NT (3.3 kg P ha-1 yr-1) and high-residue-level (3.4 kg P ha-1 yr-1) than under CT (2.6 kg P ha-1 yr-1) and low-residue-level (2.4 kg P ha-1 yr-1) treatments. Soybean yield declined at a similar rate in the first three years, but increased at a similar rate over the subsequent three years in all tillage-treatment combinations. Increasing SOM and TC over time indicated that the silt-loam soils of the Mississippi River Delta region have the potential to accumulate C in the top 10 cm at increasing rates beyond six years from initial conversion to alternative residue management practices. Implementation of the appropriate residue management practices has the potential to improve soil quality and maintain long-term productivity of silt-loam soils in the Mississippi River Delta region of the mid-southern United States.
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    Status of Selected Properties of Soils under Crop Livestock Farming System in Eastern Ethiopia
    (Science Domain, 2014) Wogi, Lemma; Msaky, J. J; Rwehumbiza, F. B. R; Kibret, Kibebew
    nformation on soil properties and fertility status of soils at farm levels under particular farming system is essential for boosting farm productivity and for sufficient food production. This study was conducted to investigate status and properties of soils under crop-livestock farming system, where crop grains are produced for food security and residues for animal feed and domestic fuel consumption. For the study, two farms under similar farming system were selected from two districts in eastern part of Ethiopia: Adele farm from Haramaya and Bala Langey farm from Kersa districts. Soil samples were collected from crop fields of each farm and analyzed following standard methods for soil physical and chemical analyses. The results indicate that soil textural class is sandy clay loam at both farms. The mean bulk density values were 1.43 and 1.39g cm-3 for Adele and Bala Langey farms, respectively. The soil reaction for Adele farm was neutral (pH=7.23) whereas soils of Bala Langey farm had slightly acidic reaction (pH=6.57). Organic carbon contents of soils of both farms were low, less than 1.5%. Nitrogen was low for Adele farm soils (<0.15%) and in the moderate range for Bala Langey farm soils (0.15-0.25%). Available soil P was very low at both farms (<10mgkg-1 ). Extractable soil sulfur was also low for both farms (<5 mgkg1 ). CEC of the soils of Adele farm was very high (>50Cmol (+)kg-1 ) and it was high (>40 Cmol(+)kg-1) for Bala Langey farm soils. Exchangeable base contents and EDTA extractable micronutrients were in the sufficiency ranges for soils of both farms. This study indicated that very low available phosphorus, low organic carbon and nitrogen followed by sulfur are the most productivity limiting factors associated with soil fertility as a result of crop residues removal for animal feed and domestic fuel consumption. Intervention management should focus on the enhancement of organic carbon, phosphorus, nitrogen and sulfur.
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    Determination of land productivity under maize-cowpea intercropping system in agro-ecological zone of mount Uluguru in Morogoro, Tanzania.
    (Global Journal of Agricultural Sciences, 2014) Nyasasi, Beatrice Thomas; Kisetu, Eliakira
    The present study assessed the response of maize (Zea mays L.) and cowpea (Vigna unguiculata L. Walp) under sole and intercropping systems. It also determined potential of intercropping system with respect to the proportion of land used for cultivation and the area of land saved. Results indicated that the above-ground total biological yield in sole maize (31.8 t ha-1 ) was insignificantly (p=0.055) larger than in maize (26.7 t ha-1 ) intercropped with cowpea. The yield in sole maize (6.53 t ha-1 ) was significantly (p=0.003) higher than in maize (6.47 t ha-1 ) intercropped with cowpea. The mean number of pods per plant in sole cowpea (7.7) was significantly (p=0.039) higher than in cowpea (6.8) intercropped with maize. In addition, the mean number of seeds per pod in cowpea intercropped with maize (15.0) was significantly (p=0.009) lower than in sole cowpea (15.43). Furthermore, cowpea seed yield in sole cowpea (6.7 t ha-1 ) was significantly (p=0.022) higher than in intercrop (6.25 t ha-1 ). Further to that, the land equivalent coefficient between maize and cowpea was 0.92 and the competitive ratio between the two crops when intercropped was 1.07. The land saved when the two crops were intercropped was 47.9%.
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    An overview of underutilized benefits derived from Azolla as a promising biofertilizer in lowland rice production
    (cell press, 2023) Marzouk, Said H; Tindwa, Hamis J; Amuri, Nyambilila A; Semoka, Johnson M
    Currently, there is no doubt that Azolla can compensate for the nitrogen requirements of rice in different agroecological zones. Compared to synthetic N-fertilizers, Azolla has various positive impacts on lowland rice production, including improving soil fertility, minimizing weeds, increasing soil organic carbon, improving microbial biomass, and thus nutrient cycling and enhancing rice growth and yield. However, Azolla has not been accepted globally by rice farmers for field use and so far, farmers are relying on increasing rates of synthetic N fertilizers instead of taking advantage of Azolla which will improve long-term soil fertility and health. This systematic literature review and scientific evidence could help policymakers, scientists and researchers to understand the benefits, limitations, and innovative ways of utilizing Azolla as a cost-effective and eco-friendly amendment in rice production. The paper uses Preferred Reporting Items for Sys tematic Review and Meta-Analysis (PRISMA) method to review the hidden potential of Azolla as a biofertilizer in paddy and summarizes its benefits and problems by collecting information from different sources and presenting under different subheadings such as critical factors affecting Azolla growth and nitrogen fixation, nitrogen fixation of Anabaena Azollae and their contribution in soil health, release and availability of Azolla-N to rice, amounts and time of Azolla inoculation, influence of Azolla on ammonia volatilization, contribution of Azolla to yield and yield compo nents of rice, and impact of Azolla on weed emergence in rice cropping system. Literature indi cated that the use of Azolla as green manure incorporated before rice transplanting or grown together with rice and left until a few days of harvest alone or in combinations with other syn thetic fertilizers in the lowland rice production saved the nitrogen requirement of rice up to 60 kg N ha− 1 , it enhances the availability of nutrients, improves physiochemical properties of soils, minimizes soil salinity, reduces the soil pH, and minimize weed germination. However, it was observed that incorporating Azolla as green manure is labor-intensive, and maintaining the Azolla inocula and phosphorous requirement are major restrictions for farmers. Therefore, under standing mechanism of spore production, educating farmers on cheaper alternative ways of Azolla application, and testing different species of Azolla over different agroecological zones will help in maintaining Azolla biomass and applying it at low cost for further environmental conservation.
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    Response of Irish potato to NPK fertilizer application and its economic return when grown on an Ultisol of Morogoro, Tanzania
    (Scienceweb Publishing, 2014) Shaaban, Husna; Kisetu, Eliakira
    A field experiment was conducted to determine the effects of different rates of NPK fertilizer on performance of Irish potato (Solanum tuberosum L.). This experiment employed use of 150 and 300 kg ha-1 of NPK (23:10:5) fertilizer and a local cultivar Alika of Irish potato as a response crop. Results indicated that the significantly (p < 0.05) highest average marketable number of tubers per plant (3.5) and tuber yield (18.74 t ha-1 ) was recorded at an application of 300 kg NPK ha-1 . The lowest average number of tubers per plant (2.2) was recorded in the absolute control while the lowest tuber yield (14.99 t ha-1 ) was recorded at 150 kg NPK ha-1 compared with the absolute control (15.97 t ha-1 ). The coefficients of determination (R2 ) from the linear regression model showed that the variation in tuber yield was 50.7% with NPK fertilizer, 21.4% with number of tubers per plant and 23.6% with tubers per plot. Partial budget analysis indicated that the net benefit was in the decreasing order of 300 kg NPK ha-1 (5,335,500 Tshs/ha) > absolute control (4,135,000 Tshs/ha) >150 kg NPK ha-1 (3,552,000 Tshs/ha). The benefit cost ratios obtained for the absolute control, 150 and 300 kg NPK ha-1 were 2.1, 1.9 and 2.3, respectively, while the marginal rate of return for the two rates of fertilizer were -0.45 and 1.27, respectively. Based on the total variable costs and net benefit, NPK applied at 150 kg ha-1 was dominated (D) by the absolute control.
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    Uranium contamination in drinking water and foodstuffs in Bahi District, Central Tanzania
    (JCEE, 2014) Marwa, Ernest M.M; Mziray, Zainab J; Chove, Bernard E; Kaaya, Abel K
    A field survey was conducted in Bahi District in Central Tanzania to investigate uranium levels in drinking water and to evaluate its contamination in some foodstuffs as proxy to their safety for human and animal consumption. Regularly consumed cereal grains, cassava leaves, salt, soda ash, catfish, flamingo meat, surface and underground waters were randomly sampled in the district and analyzed using inductively coupled plasma - optical emission spectrometry (ICP-OES). The study found extremely high levels of uranium in surface and underground waters of up to 1233µg L-1 , a value that exceeds the World Health Organization standard of 30 µg L-1 by a factor of 41. Soda ash, which is locally consumed and some is exported, had a very high value of 1910 µgU kg-1 . Finger millet grains, catfish and flamingo had 32, 17.98 and 31.78 µgU kg-1 , respectively, values that were higher than the natural background level of 14 µgU kg-1 found in some common foodstuffs by the European Food Safety Authority. It was concluded that drinking water and consuming foodstuffs with high levels of uranium is endangering human and animal life in Bahi District. This may cause leukemia, brain disorder, kidney failure, lung damage and/or bone cancer. The public should therefore be informed about this risk and relevant authorities should undertake regular screening of food products from the affected district as a mitigation measure to avoid health problems in future.
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    Phosphorus Adsorption Isotherm: A Key Aspect for Soil Phosphorus Fertility Management
    (Science Domain, 2014) Wogi, Lemma; Msaky, J. J; Rwehumbiza, F. B. R; Kibebew, Kibret
    Characterization of soils in terms of phosphorus adsorption capacity is fundamental for effective soil phosphorus fertility management and for efficient utilization of phosphorus fertilizers. Thus, this study was conducted to investigate the phosphorus adsorption characteristics of soils of two farms and to elucidate the implication of soil phosphorus adsorption isotherm studies for soil phosphorus fertility management. The two farms, representing the major farming systems of the respective districts, were selected from Adele village in Haramaya district and Bala Langey village in Kersa district in eastern Ethiopia. Soil samples were collected from the crop fields at Adele and Bala Langey farms. Two different P-bearing sources, potassium dihydrogen phosphate (KH2PO4) and diammonium phosphate (DAP-(NH4)2HPO4), were used for the adsorption isotherm studies. The adsorption data were fitted to the linear and Freundlich adsorption isotherm models. Both models revealed that soils of both farms had different P adsorption capacity from the two P sources. Amount of P adsorbed from DAP solution was higher than the amount of P adsorbed from KH2PO4 solution in soils of both farms. Phosphorus adsorption capacity of Adele farm soils was higher than that of Bala Langey farm soils. Therefore, soils of the two farms should be managed differently for P fertility. Percentages of P adsorbed (% Pa) and P remained in the equilibrium solution (% EC) were also calculated. By plotting the two percentages i.e. % Pa and % EC against the initial concentration of P (IC), two regions were observed. The two regions were described as P intensity and quantity factor windows. Based on the intensity and quantity factor windows, at currently existing soil condition, between 200 and 500 kgha-1 P should be applied as fertilizer to soils of Adele at 0-30 cm depth for immediate benefits and soil P fertility maintenance.
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    Spatial Distribution of Organic Carbon and Nutrients under Farmers’ Crop Residue Management Practices in Eastern Ethiopia
    (Science Domain, 2015) Wogi, Lemma; Msaky, J. J; Rwehumbiza, F. B. R; Kibret, Kibebew
    Understanding the distribution and transport of organic carbon and nutrients under any management in a farming system is vital for predicting the sustainability of a farming system. This study was conducted to characterize the spatial distribution and transport of organic carbon and nutrients under farmer’s crop residues management involving complete removal of the residues and to identify which nutrients are highly affected by such management practices. Two farms, representing the major farming systems of the study areas, were selected from Adele and Bala Langey villages in Haramaya and Kersa districts, respectively in Eastern Ethiopia. Soil samples were collected along the slope gradient from the crop fields and at a given distance from home in homesteads of each farm at a depth of 0 – 30 cm. The samples were analyzed following standard methods for soil organic carbon and nutrient contents. Results indicated that distributions of organic carbon and nutrients were affected by slope gradients in crop fields and by distances in homesteads at both farms. Results showed that 2.95 and 2.15% OC, 0.52 and 0.25% N, 100.15 and 41.23 mgkg-1 available P, and 25.05 and 1.65 mgkg-1 extractable S were accumulated near homes of the households at Adele and Bala Langey farms, respectively. Quantities of OC, N, P, and S were less than 2%, 0.15%, 25 mgkg-1 and 2 mgkg-1, respectively in the crop fields at both farms. Amounts of N transported from Adele and Bala Langey crop fields through haricot bean residue were 4.70 and 5.60 g/kg dry matter, respectively. The extent of crop residue removal management effects on the distribution of the nutrients, from the most to the least affected, follows the order P > OC > S > N > exchangeable bases > micronutrients at both farms. Intervention management should focus on reversing the flow of organic carbon and nutrients from crop fields to the homesteads and minimizing unequal distribution of organic carbon and nutrients in the farming system at both farms
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    Options for up-scaling technology adoption by smallholder farmers for food security through irish potato production in Rungwe district, Tanzania
    (Infogain Publication, 2016-05) Marenge, Upendo Victus; Kisetu, Eliakira
    This study was conducted to determine the existing and feasible options for adoption of technologies that are involved or to be involved in Irish potato (Solanum tuberosum L.) production with the focus on Nzunda, Ntokela and Ndaga villages in Rungwe District. This was prompted by the unreliable production systems and the low life standards of the smallholders in the district. One-point in-time purposive survey was conducted using structured questionnaires and physical observations where 45 households were studied. The results also indicated that the effect of socio-economic and institutional factors were significant (LSD0.05 = 1.8) in determining Irish potato production in Ntokela village. In addition, the effect of institutional and socio-psychological and land tenure factors were significant (LSD0.05 = 6.6) for Irish potato production in Nzunda village. However, none of these factors were significant (LSD0.05 = 32.9) in Ndaga village. Results indicated that Irish potato produced was positively correlated with the farmer’s capital and/or access to credits (r = 0.700), farming experience (r = 0.225), extension services to impart awareness (r = 0.698), contribution of innovations (r = 0.771), sex-female (r = 0.96), and innovative agricultural inputs such as seeds, fertilizers, herbicides, pesticides, and fungicides (r = 0.525). Female household head were mostly favoured by adoption of technologies in Irish potato production. These were the factors identified to be pertinent in adoption of Irish potato production technologies for Irish potato production in Rungwe district
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    Incorporating pigeon pea compost with minjingu fertilizer brands to determine their effects on maize production in Morogoro, Tanzania
    (World Journal of Agricultural Sciences, 2013-10-24) Kisetu, Eliakira; Mtakimwa, Ziada Salum
    This study intended to find alternative ways of increasing phosphorus (P) in soils using Minjingu fertilizer brands since maize yield in Tanzania has been retarded by low soil fertility. Maize (Zea mays L.) var. TMV-1 was used as a test crop. The treatments used (g per 2.16 m2 plot) were: absolute control (C), Pigeon pea compost (PP) (100), M-Mazao (MM) (420), Hyper (MH) (160), MM + PP (520) and MH + PP (260). The results showed that Agronomic Efficiency (AE) varied significantly (p <0.001) among treatments. Harvest index (HI) also differed significantly (p ≤0.05). This study revealed that exclusive application of Minjingu Hyper fertilizer to maize proves to be superior to Minjingu Mazao fertilizer by having the highest harvest index (24.7%) with relatively high maize yield (2.94 t ha 1 ). The former fertilizer brand compares better with the latter, which produced yield of 1.65 t ha-1 and harvest index of 6.94%. Furthermore, upon incorporation of pigeon pea compost, Minjingu Mazao fertilizer recorded the highest yield (3.85 t ha 1). This differed slightly numerically but was statistically similar with yield obtained when compost was incorporated with Minjingu Hyper fertilizer (3.64 t ha 1).
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    Distribution and incidence of cylas puncticollis in sweet potato and their economic losses in small holder farming systems of Gairo district, Tanzania
    (Ecronicon, 2016-07-01) Mapesa, Jofrey Andy; Kisetu, Eliakira
    This study assessed the incidences, distributions and yield losses in sweet potatoes (Ipomoea batatas (L.) Lam) associated with Cylas puncticollis in small holder farming systems of Gairo District, Tanzania. This was accelerated by the fact that small holder farm ers produce sweet potatoes in areas with high risks of sweet potato weevils. At the farmer’s fields, plots measured 5m × 5m in each replicate, sweet potatoes were harvested and assessments were done on the variables such as number of weevils, species, roots infested by Cylas and areas infested (above-below ground). Two sweet potato varieties namely Morogoro and Shangazi in Mtumbatu village were involved. Results indicated that the number of weevils and their species were more in vines than in roots but serious damage was observed in roots. These were also more prevalent in variety Morogoro compared to variety Shangazi. The mean number of undamaged sweet potato was significantly (P<0.001) higher in Shangazi variety (54.7) compared to Morogoro variety (43.3). In addition, economic losses of marketable roots were highly caused by Cylas infestations (USD 306) in variety Morogoro and breaking (USD 425), cutting (282.5) and rotting (USD 67.5) in variety Shangazi. It was concluded that variety Morogoro is more susceptible to economic losses caused by Cylas infestations compared to variety Shangazi. Therefore, variety Morogoro should be harvested as early as it reaches maximum maturity and where possible farmers in Gairo District and similar areas should invest more on variety Shangazi.