Soil Science Collection
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Item The effect of seed factors and the duration seed remains in soil before the onset of rains on establishment of maize and sorghum(Sokoine University of Agriculture, 1997) Tarimo,Bartholomew DonatA study was undertaken to: (a) assess the seed quality in commercial and farmers planting seed,(b) extent of seed ageing in storage and (c)investigate the monitor the effect of length of time seed remain in soil before onset of rains on establishment of maize (Zea mays (L) and sorghum (Sorghum bi color (L). Seed of three cultivars of maize (Staha, TMV-1, and Kito) and one sorghum cultivar(Tegemeo) were from bought Tanzania Seed Company (TANSEED), Morogoro branchz and from farmers around Morogoro Municipality. The bought seed was stored alongside TANSEED and farmer's seed. Initially, seed samples from each lot and each farmerz were taken to the laboratory for refrigeration to minimize ageing and hence to serve as control. Acquired seed was initially subjected to a germination test to assess its quality as a planting material.Germination test were conducted in a sandbox set at a matric suction of IkPa. The study on the effect of length of time seeds remain in soil before the onset of rains on establishment was conducted both in glasshouse and in the field using high,medium and low vigour seeds.High vigour seeds were the fresh / imaged seed samples from the seed lots.Medium and low vigour seeds were obtained by artificial ageing of fresh seed for 2 and 3 days respectively.Planting, both in the glasshouse and in the field was done at an interval of 3 days z that is 0 r 3, 6, 9, 121 15 days.Watering was on the 15th day with an equivalent of 20mm of rainfall. Seeds from TANSEED had ranging from 93 to 100%, initial germination percentage (maize) and 92 to 96% (sorghum)・Seeds from farmers had gemination percentage varying from 64 to 99% (maize) and 8 to 65% (sorghum)・seeds from TANSEED had relatively capacity than those from farmers. Higher germination Seeds from farmers had high initial seed moisture content (SMC) seed. Overall sorghum than commercial Sorghum had higher SMC than maize irrespective of the source ・Initial SMC was about 10 and 11% for maize and sorghum respectively.At the end of the studyz SMC had increased to an average of 12 and 14% for maize and sorghum respectively. Time to 50% germination (T50) increased with storage time for seeds obtained from TANSEED. maize cv St aha lot A were 2.2,T50 values (in days) for (initially) , 2.4 one month) and 2.7 after two months)・(after Seeds from farmers showed no consistent trend.In both field and glasshouse emerged earlier than maize seeds.studies,sorghum seeds Sorghum seeds started emerging 3 days after watering whereas for maize emergence started on the 4th day.The length of time seed remained in the soil(dry planting)had no effect on percentage emergence in the glasshouse experiment. Under field conditions percentage emergence decreased with the length of time seed remained in soil before watering.High vigour maize seeds had relatively higher proportion of seeds categories.which emerged than Insorghum,medium and low vigour the other two vigour seeds performed better in terms of emergence than high vigour seeds.The average shoot length for maize 10 days after watering varied from 157mm to 238mm and 90.7mm to 248mm for the glasshouse and field experiments respectively.Sorghum seedlings grown in the glasshouse had mean shoot lengths varying from 121mm to 172mm and the mean values recorded in the field varied from 63mm to 101mm.Item Assessment of in-situ rainwater harvesting techniques for improving smallholder maize production in semi arid areas of Morogoro, Tanzania(Sokoine University of Agriculture, 2003) Bwana,Thomas NestoryA study was conducted at Morogoro, Tanzania during long rains ('Masika') to evaluate the effect of in~situ rainwater harvesting (RWH) techniques in improving maize yield. Three commonly used techniques, ridging after planting (RA), ridging before planting (RJB), and tied ridging (TR) were tested against a no tillage practice locally known as "kuberega" (K) on an Oxic Paleustalf soil with maize (Zea maize L.) variety TMV1 as the test crop. Daily rainfall was recorded and the total rainfall received during the 2001/02 growing season was 562 mm with a series of dry spells. Moisture content at 0-15 and 15-30 cm depth was measured twice weekly. Significantly (p<0.05) higher soil moisture variation and lower moisture content were noted in treatment K than in the other treatments. Treatments RB and TR had lower moisture variations and higher moisture content throughout the season. Grain yield, biomass, plant height, bulk density, infiltration rates (on the ridge and in the furrow), runoff and soil loss were also measured. Significant differences were observed among the treatments (p<0.05) in runoff, soil loss, on ridge infiltration, grain yield, and biomass. The maize yield ranged between 2.97 Mg/ha and 3.89 Mg/ha for treatments K and RB, respectively. The runoff loss was highest for K and least for TR. Treatments K and RA did not differ significantly from each other but differed significantly from RB and TR (p<0.05). Soil loss had a similar trend as that of runoff. More runoff loss was recorded early than late in the season. On ridge infiltration was not significantly different for treatments TR, RA, and RB but was significantly higher than the control (K) at (p<0.05). On furrow infiltration, however, had a reverse order with K having higher rates. Bulk density in both depths (0-15 and higher bulk density. The results show that ridges are effective in-situ rainwater harvesting technique that conserves water and soil and improves productivity.However, ridging after planting is inferior to both ridging before planting and tied ridging.15-30 cm) was not statistically different (p<0.05), however treatment K had slightlItem Effects of selected insecticides on microbial numbers,leucaena decomposition and biological nitrogen fixation(Sokoine university of Agriculture, 1997) Ng'ang'a, Josephine NyamburaThe effects of Lannate and Karate on the decomposition of leucaena green manure and nitrogen fixation by cowpea were evaluated, after establishing their inhibitory effects on the decomposer microorganisms and their toxic effects on the bradyrhizobia in vitro.In the decomposition experiment,manure the in in the perforated plastic litter bags was buried (10 cm) soil contained in wooden troughs and the insecticides were applied on the soil at final concentrations of 0.5 and 1.5 ppm for lannate or and 0.51.0 ppm for decomposition process was monitored at 0, after weeks matter, and incubation by measuring residual organic carbon,inorganic-N heterotrophic content microbial of count karate.1, the 5 and 73,residual dry residual total nitrogen was the soil.The determined total at each sampling time.The effects of these insecticides each at 0.5 and 1.5 ppm on the covrpea-Bradyrhizobium symbiotic relationship were assessed in potted soil. Cowpeas were grown and harvested after 35 days. Nodule numbers and dry weight,shoot dry weight and nitrogen content were assessed.Results of these studies indicated that lannate and karate had an apparent depressive effect on the growth of the heterotrophs at the 0.5 ppm concentration but not at higher concentrations. The bradyrhizobial proliferation invitro was more affected by lannate than karate. However, nodulation and nitrogen fixation was not affected by any of the insecticides at significantly any of the the two concentrations tested.It was concluded from this study that insecticides, when applied even up to ten times the field recommended rate have no profound effects heterotrophic microorganisms, their ability to on the decompose leucaena green manure and on biological nitrogen fixationin cowpeas. However, the very severe depressive effect of lannate on the cowpea-bradyrhizobia in vitro, may warrant further studies in soils.Item Pedological investigation and characterization in Litembo village, Mbinga district, Tanzania(Sokoine University of Agriculture, 1997) Meliyo, Joel L.A pedological investigation was carried out in Litembo village, Mbinga district (Tanzania) to identify the various soil types and characterize them in terms of their physical, chemical and mineralogical properties. The soils were classified according to FAO-Unesco and USDA Soil Taxonomy systems. On the basis of soil and other ecological parameters the potentials and constraints of the land resources were assessed. Standard soil survey methods and laboratory procedures were utilised to generate both field and laboratory data. Results indicate that Litembo village has four major landforms i.e. plateaux, hills, piedmonts and valleys Most piedmont soils are deep to very deep having dark brown to dark reddish brown sandy clay topsoils and dark red to red clayey subsoils. The hills and plateaux have shallow sandy clay loam soils. All the studied soils are well drained to excessively well drained except those of the valley bottoms which are poorly drained. Topsoil bulk densities range from 0.99 to 1.2 Mg m'3 whereas subsoil values are slightly higher. Total porosity ranges from 56 to 72% in the topsoils and from 40 to 53% in the subsoils. Topsoils have lower penetrometer resistance (PR values 0.1 to 0.28 MPa) than subsoil (PR values 3.97 - 5.52 MPa). Available water capacity (AWC) of most topsoils ranges from 15 to 25% by volume and the values decrease slightly with depth. AWC per meter range from 125 to 177 mm which is medium to high. General soil fertility status is poor. Soil reaction is very strongly acid to strong acid with pH values between 4.4 and 5.4 in topsoils and 4.4 and 6.0 in subsoils. Total nitrogen ranges from very low to medium (< 0.03 - 0.3); phosphorus, bases, CEC and base saturation are low. OC ranges from low to very high in topsoils and very low in subsoils. The clay mineralogy is dominantly kaolinitic with accessory amounts of gibbsite and goethite. The piedmont soils classified as Ferric Acrisols, Haplic Acrisols and Humic Acrisols, plateau soils classified as Humic Acrisols; soils of the as Dystnc Leptosols and Haplic Acrisols and valley bottom soils as Umbric Fluvisols. From the results of this study it is concluded that Litembo soils developed under intensive leaching environment, facilitated by a mountainous/hilly topography. Fertility status is poor, and due to steep slopes and weak soil structure Litembo soils are prone to erosion. The traditional farming system (ngoro) seems to control soil erosion on steep slopes. It is recommended that steep slopes should be planted with trees that will protect soil from erosion. Use of the traditional farming system (ngoro) should be encouraged. Due to low soil fertility status, use of fertilizers both artificial and organic manures is recommended Non-acidifying fertilizers should be preferable because of the low soil pH values. The study area lacks climatic data. More research in this line is recommended. Research on different land use alternatives which can sustainably be applicable in the village should be carried out.Item Land suitability assessment of the Wami plains in Morogoro, Tanzania with respect to the production of the main food crops and extensive grazing.(Sokoine university of Agriculture, 2000) Kileo,Emmanuel P.ABSTRACT A study was conducted at Wami Plains in Morogoro to assess the suitability of land for the production of the main food crops and for extensive grazing. Field land resources survey was conducted covering an area of 35,810 hectares. Soil profiles were excavated, studied and sampled for laboratory analysis. Soils of Wami Plains are mostly well drained,sandy clay loams, except on the valley bottoms, floodplains and mbuga where they are poorly drained. They have low to medium available water capacity (83 - 135 mm/m) except profile NYN-P7 which has high available water capacity (164 mm/m). The soils are generally poor in chemical fertility. The levels of nitrogen range from very low (0.04%) to low (0.17%) while those of organic carbon are between low (0.66%) to medium (1.46%). Available phosphorus contents range between low to medium (0.96-16 0 mg/kg) The level of micronutrients in these soils is adequate except for Zn which is rated as inadequate for most crops. The soils were classified according to both FAO-World Reference Base and USDA Soil Taxonomy systems. The FAO-WRB soil names with their mapping units in brackets are as follows: Chromi-Rhodic Cambisols and Hapli-Hypocalcic Calcisols (Alluvial fan); Rhodi-Profondic Lixisols (Ridge summits); Rhodi-Profondic Lixisols (Ridge slopes with red soils); Hypereutri-Ferralic Cambisols (Ridge slopes with sandy soils); Hypereutri-Mollic Fluvisols and Calcari-Mollic Cambisols (Valley bottoms); Chromi-Profondic Lixisols and Hapli-I-Iypocalcic Calcisols (Flats with red soils); Calcari-Mollic Fluvisols (Flats with sandy soils); Hypocalci-Endosodic Calcisols (Floodplains) and Endosodi-Pellic Vertisols (Mbuga). Three land utilisation types (LUTs) (maize, rice and extensive grazing) were selected for land suitability evaluation and the results of physical suitability evaluation are as follows: About 38% of the area was classified as moderately suitable, 44% marginally suitable and 18% physically not suitable for maize production. As for rice production, about 55% of the area was classified as marginally suitable and 45% is physically not suitable for the LUT. About 84% of the area was classified as moderately suitable for extensive grazing while only 16% is marginally suitable for the LUT. Major limitations in these soils are: nutrient availability and retention, moisture availability, flooding hazards, oxygen availability to roots and biological hazards.Item Soil survey amd land evaluation of a part of the university farm - Morogoro for rainfed agriculture(Sokoine University of Agriculture, 1984) Mpepo,Haston Longwani JamesLack of a systematic and detailed soil survey and land evaluation report for guiding the utilization of the farm necessitated this study.About 1, 097 ha comprising the Northern part of trie farm was covered. It is possible to grow maize, sorghum, soyabeans, fieldbeans, ground- nuts and rice. JItem Influence of shapes of the Ngoro on depression storage and crop performance.(Sokoine University of Agriculture, 1999) Mogasa Pili MogasaA field experiment was conducted in the 1995/1996 growing season on a slope of 30% on the foothill of the Uluguru Mountains in Morogoro, Tanzania. The aim of the experiment was to evaluate the influence of various Shapes of the ngoro cultivation system on (i) soil moisture storage (ii) depression storage and (iii) maize growth parameters and yield. Three Shapes of the ngoro pits namely: Shape 1 (Rectangular with the longest side across the slope), Shape 2 (Rectangular with the longest side along the slope) and Shape 3 (Square) were compared with flat cultivation, a common practice in the study area. The various ngoro Shapes stored at least 1.36 times more soil moisture than flat cultivation (significant at the 5% level). The position of the ridge on the four sides of the pit had no significant effect on soil moisture storage (P < 0.05). Ngoro cultivation showed significantly higher amounts of soil organic matter (41% to 53%) than flat cultivation which had the lowest (about 6% organic matter, P < 0.05). Top soil (0 - 10 cm) had 15% organic matter (o.m.) compared to 7% and 6% o.m. at a depth of 10- 20 cm and 20-30 cm, respectively. Bulk density was significantly lower in the ngoro compared with flat cultivation (P < 0.05). Shapel had significantly (about 27%) lower depression storage compared to Shapes 2 and 3 (P < 0.05). Ngoro cultivation produced about 66% more grain than flat cultivation. This yield difference was significant (P < 0.05). The position of the ridge on the slope had no significant effect on maize growth and grain yield (p < 0.05). Therefore, if the aim is to improve maize performance in the study area any Shape of the ngoro can be employed as found out from this study.Item Soil classification, pedogenesis and land evaluation in Kapini area Lusaka, Zambia.(Sokoine University of Agriculture, 1983) Kaltia,CuuluBack ground -information related to classification, pedogeneiis and laud evaluation is briefly given. It includes information on geology, geomorphology, topography, drainage, climate and vegetation. Literature on soil classification in relation to local and inter-■:n-3ti&2.yl classification systems is reviewed. Literature review on. pedogenesis critically focus on soil genesis work in Zambia in relation to important soil’ formng factors.International and local land evaluation systems are reviewed.together with concepts that are not used consistently and have often caused lots of confusion in land evaluation. The results of the study can briefly be summarised as follows: 1.The soils are classified, into four major orders:Ultisols, Alfisols and InceptIsols.Oxisols, (Soil Survey Staff 1975) or as Ferralsols, Luvisols, Acrisols, Hegosols and Lithosols (PJL.O./craESCO 1974). Classification is pursued up to the family level and sub-unit level respectively*. 2.The major processes which are important in pedogenesis are:Eluviation, illuviation, Cumilation, Pedoturbation, Desilication,Fertilization Decomposition and Synthesis.be the most important soil forming factor.Geology was found.to the most important soil forming factor. 3.Most of the soils in the area are moderately suitable to crop production (60^).- The major limitation to crop production are fertility (for the Oxisols), flooding, moisture availability, stoniness; and rooting depth« 4.Socio-economically the area is not suited to cash crop production at subsistence and intermediate management levels* 5.The area has a high potential for crop production especially with improved management.level'*Item Evaluation of the fertility status of the soils and maize response to N and P in Nkasi district, Tanzania(Sokoine University of Agriculture, 2012) Chang’a, Clarence VitusABSTRACT A Study was conducted to evaluate the fertility status of the soils and maize response to N and P in Nkasi District, Tanzania. The objectives of the study were to: determine and characterize the fertility status of the soils, assess the response of maize to N and P. suggest possible N and P fertilizers rates for optimum maize yield and appraise the economics of N and P fertilizer use in maize production. Ten composite soil samples were collected at a depth of 0-30 cm from Mkole. Nkomolo 1. Mashete. Chala. Swaila, Milundikwa, Nkomanchindo, Myula. Ntatumbila and Isale villages. The soil analytical results showed that the soils were sandy loam, moderately acidic, low in some macronutrients and micronutrients, SOM. CEC and PBS. hence from the soils analytical data three villages Ntatumbila, Mashete and Nkomolo 1 with the low N (%) and P (mg P kg'1) were selected for field experiments to determine the response of maize to different levels of N (0, 50, 100, 150 kg N ha'1) and P (0. 25, 50, 75 kg P ha'1). A 42 factorial experiment in CRBD with four replicates was used. The sources of N and P were urea and TSP, respectively and 100 kg K ha'1 was applied to all plots as KC1. NiooPsoand N150P75 significantly increased N and P contents of maize whole plant and maize grain yields compared to the control. Nitrogen contents in the maize plants were rated as low and ranged from 1.42 to 3.41% while P contents were rated as adequate for the NP combinations and ranged from 0.19 to 0.65%. Maize grain yield increased from 1.31 to 6.31 t ha'1. From the maize grain yields economic analysis and agronomic judgments the treatments N100P50 and N100P75 would be the most profitable fertilizer rates in Nkasi district.Item Impact of soil conservation measures on the properties and productivity of volcanic soils on the slopes of mount Meru, Arusha, Tanzania.(Sokoine University of Agriculture, 2001) Ngatoluwa,Ramadhan ThabitA study was conducted to examine the effect of soil conservation measures on soil properties and productivity of volcanic soils on the slopes of Mount Meru, Arusha Region. The experiment was conducted on 27 plots in two agroecological zones namely: medium (1,400-metres above sea level (m.a.s.l.) and high (1,700 m.a.s.l.) altitude zones. Two commonly used soil conservation measures, Fanya Juu and Contour bunds, were tested against non-conserved plots. The effect of soil conservation measures on soil properties was examined by collecting and analyzing soil samples from all treatments. The effect of soil conservation measures on soil productivity was assessed by planting common beans (Phaseolus vulgaris var. Lyamungo 85) as the test crop. Soil conservation measures had no significant effect on the surface soil chemical properties namely: pH, CEC, exchangeable bases, total nitrogen, available phosphorous and organic matter. The depth of Ap horizon in the conserved plots was not significantly different from one another (P=0.05). However, unconserved plots registered the lowest topsoil depth and they were significantly different from conserved plots. Bean yield differed significantly (P=0.05) due to the effect of soil conservation measures. There was no interaction (P=0.05) between conservation treatments and their respective position in the agroecological zone.Mean bean yield ranged from 0.789 Mg ha'1 in unconserved to 1.367 Mg ha'1 in Fanya Juu terraced plots. Fanya Juu treatments significantly out-yielded (P=0.05) Contour bund plots by 0.127 Mg ha'1. A similar trend was observed for dry matter yield. Dry matter yield differed significantly (P=0.05) due to treatment effect. Fanya Juu terracing resulted in two folds grain yield compared to control. The highest dry matter yield was registered in Fanya Juu plots, followed by that from Contour bunplots while unconserved plots produced the lowest yield. Mutiple regression analysis showed that depth of topsoil (Ap-horizon) significantly affected bean yield (P=0.01, r=0.64). Depth of topsoil and surface available phosphorous were regressed against bean yield and it was found that the thickness of the Ap horizon had higher impact on bean yield compared to surface available phosphorous (P=0.01 and R=0.78). Soil moisture profile (0-90 cm) in conserved plots differed significantly (P=0.05) from that in unconserved plots. Conserved plots had higher profile moisture content throughout the growing season. However, soil moisture profile did not differ significantly (P=0.05) between Fanya Juu and Contour bund plots. This suggests that the two conservation measures have similar effect on soil water conservation. The results from this study confirm the importance of soil conservation measures on Ap horizon development, water holding capacity and crop yield.Item Effectiveness of Fanya Chini terraces on soil properties and crop yield in the north-wester!' part of the Uluguru mountains, Morogoro, Tanzania.(Sokoine University of Agriculture, 2001) Mkoba, Appia PaulA field experiment was conducted in the north-western part of the Uluguru Mountains, Morogoro District, to determine the effect of Fanya chini terraces on selected soil chemical and physical properties and crop performance. Eighteen experimental plots of 12 m x 3 m were established on farmers' fields. Plots with Fanya chini terraces were compared with those with no conservation structures. Maize (Zea mays L.) was used as the test crop. No inorganic fertiliser was applied in order to reflect farmers’ practices in the area. Soil samples from the experimental plots taken at the beginning (initial) and at the end (final) of the study were analysed to assess the changes in soil physical and chemical characteristics that had occurred during the cropping period. Most of the observed soil chemical variables were slightly (but insignificantly) higher in plots that had no conservation structures (unconserved plots) and their magnitude tended to increase along the slope. Organic carbon, total nitrogen and exchangeable calcium showed a significant increase (P = 0.05) in unconserved plots in the final soil samples. There was a significant difference (P = 0.01) in PR between the Fanya chini terraced plots and unconserved plots both at the beginning and at the end of the experiment. Fanya chini terraced plots had mean PR value of 0.69 and 1.81 MPa compared to unconserved plots which had mean PR values of 0.78 and 1.71 MPa at the beginning and at the end of the experiment, respectively. Maize grain yield and biomass were not significantly different between the Fanya chini terraced and unconserved plots. However, grain yield and biomass were relatively higher in the unconserved plots and they tended to increase along the slope. The exposure and spread of the subsoil from the Fanya chini channels that were about 30 to 50 cm deep may have resulted into the reduced soil fertility and the resultant lower yield observed under Fanya chini terraces. Fanya chini terraces are not the best soil conservation measure on steep slopes. Where they are already in place, Fanya chini terraces should be complemented with other soil surface management practices.Item Assessment of soil fertility status of three soils after four years of continuous application of different nutrients(Sokoine University of Agriculture, 2004) Mbanzibwa,DeusdedithA study was undertaken to assess the fertility status of three soils following four years of continual application of different nutrients. The three soils were from Mlingano, Nkundi and Sasanda, which are classified as Rhodic Kandiustox, Acruoxic Kandiustult and Dystrict Haplustand, respectively. The study was conducted under both field and glasshouse conditions. For the pot experiment conducted at the SUA glasshouse all three soils were used whereas field experiment was conducted only at Nkundi site. Soils for pot experiment were taken from absolute control plots and from plots treated with TSP and MPR at the rate of 120 kg P/ha. Under field study one more treatment, namely control for P was included. The results showed that application of different nutrients, except nitrogen, led to build up in levels of applied nutrients. Application of MPR or TSP increased levels of Bray 1-P from low to medium and high levels, respectively, in Nkundi and Mlingano soils. In Sasanda soil, Bray 1-P remained below 5 mg P/kg despite application of TSP and MPR. This was attributed to high P fixation capacity of Sasanda soil. In Nkundi soil, MPR application raised Bray 1-P from 5.0 mg P/kg to 41.7 mg P/kg whereas in Mlingano soil Bray 1-P was raised from 2.6 mg P/kg to 39.4 mg P/kg. Application of TSP raised Bray 1-P to above 105 mg P/kg in Mlingano and Nkundi soils but only to 4.7 mg P/kg in Sasanda soil. Zinc and copper increased to sufficient levels in all soils due to application of zinc sulphate and copper sulphate fertilizers. Use of TSP or MPR decreased soil pH in Mlingano and Nkundi soils but the decrease was less in soil treated with MPR. For instance in Mlingano soil, pH decreased from 5.5 to 5.4 and 5.0 for soils treated with MPR and TSP, respectively. However in Sasanda soil MPR increased soil pH from 5.0 to 5.3 and there occurred no shift in pH in plots treated with TSP. Residual P increased significantly (P = 0.05) the maize dry matter and grain yields in plots treated with TSP and MPR. The increase in dry matter and grain yields due to residual P from MPR and TSP were comparable. In Mlingano and Nkundi soils, diy matter yields ranged between 7.29 and 64.77 g/pot whereas in Sasanda soil it ranged between 2.12 and 22.10 g/pot. At Nkundi site, residual P from MPR and TSP gave yields of 4.23 and 4.73 t ha'1,respectively. Yield in absolute control and control for P treatments were 1.03 and 1.83 t ha'’, respectively. It was concluded that residual P from MPR and TSP had comparable effects on maize production.Item Evaluation of Minjingu phosphate rock products as sources of phosphorus for maize and sorghum in some Morogoro and Hai soils(Sokoine University of Agriculture, 1991) Kimbi, Gerald GervasExperiments effectiveness were partially of to evaluatethe acidulated phosphate rock conducted (PAPR) and non acidulated Minjingu phosphate rock (PR) as sources of for phosphorus maize and sorghum. Two studies was the test crop in the initial pot study and two field experiments were conducted.Maize in the field experiments while sorghum was used in the residual pot study.Five soils, namely Kwa Sadala, Mlama, Mafiga,Magadu and University Gate,varying widely in properties were used. Results of these experiments showed that all the P carriers increased yields in Mlama, Magadu and University Gate soils, indicating that the three soils were P deficient and thus required supplemental P. The KwaSadala and Mafiga soils, with high available P and nearly, neutral pH values, did not respond to either of the P sources.The initial PAPRs and results study indicated non ac i dulated PRs had the nearing that pot of University Gate that the fertilizer values TSPin soilsthe PAPRs and PRs were generally Mlama soil. In the Magadu and inferior to TSP. Results of the residual pot study showed that the PAPRs and PRs had superior residual effectiveness compared to TSP in Magadu, indicating that overMlama and time the P dissolved in the three soils.University Gate soils, carriers substantiallyItem Response of maize to phosphate released from Minjingu phosphate rock and farm yard manure applications in an oxic haplustult(Sokoine University of Agriculture, 1997) Kitua, M.J.Y.A glasshouse pot experiment was carried out to investigate the (Zea maize of response mays L combinations of MPR-Farm yard manure (FYM) applied to an Oxic Haplustult. were 0, .7.5,)to various (kraal manure),The rates of FYM applied 15 and 30 g/kg and the rates of MPR were 0, 50, 100, and 150 mg P/kg soil. The MPR-manure combinations were incubated seeds.The one for month showed results before an the sowing increase maize Bray-1-in an increase in dry extractable P by 8.3 mg P/kg soil, matter yields of 27.3 g/kg soil and phosphate uptake by 0.13%. The above increases were attributed to the P released from the solubilization of MPR and decomposition and mineralization of the farm yard manure.The small increases in Bray-lextractable phosphate increased with increasing indicate time of the gradual contact between solubilization, soil-MPR and FYM decomposition and mineralization of MPR and FYM, respectively. Response by crops to phosphate released from MPR-FYM-combinat ions' would be more pronounced when applied to the soil 6 to 12 months before planting, to ensure optimal solubilization and decomposition of the MPR and FYM, respectively.Item The effect of soil erosion on soil productivity under different management practices(Sokoine University of Agriculture, 1996) Gebremedhin, Yemane HalluA study was conducted at Sokoine University of Agriculture, Morogoro, Tanzania, to evaluate the effect of erosion soil on soil productivity different under management practices using 10mx5m runoff plots with a 4 percent slope. (BF) ,permanent cropping(RO ,coarse mesh The treatments consisted of bare grass fine (GP) , flat mesh (FM) ,cropping medium fallow(CP) ,mesh ridge(MM) , and (CM). The CP and RC were planted with maize with a population density of 41 600 plants/ha. The FM, MM,and CM were simulated canopy covers with net shading rates of 80, 55, and 40 percent, respectively, stretched 40 cm above the surface.Runoff generated during every rainstorm was collected for determining amount of runoff, soil and nutrient losses from each treatment. Soil samples from the runoff plots taken at the beginning (initial) study were analyzed for and end (final) changes properties. Amount of nutrient loss and eroded sediments were in soil of the chemical in the runoff water determined. Grain yield and biomass were determined for the cultivated treatments. Runoff ranged from 143.9 m3/ha in the GP to 2398 m3/ha in the BF. The runoff from the BF, significantly different from all (p<0.05) other treatments. Soil GP, CP, and CM were amongst themselves and loss was between 0.09 Mg/ha in the GP and 12.49 Mg/ha in the CP. There was no significant difference in soil loss between the BF and CP treatments but they differed significantly from all other treatments.Organic carbon showed a significant decrease in the final soil samples in the BF, GP, RC, and FM treatments, while TN decreased significantly (P<0.05)in the CP,RC,and phosphorus CM treatments.Likewise, available was significantly lower in the final soil samples in the GP, CP, and FM. Surprisingly, both Na*and CEC were significantly higher in the final soil sample in some of the treatments. The BF and CP treatments lost significantly (P<0.05) more OM, nitrogen, and Ca2+ than all other treatments. The loss in AVP, K+, and significantly different Mg2+ the from (P<0.05) BF and CP were amongst themselves and from all other treatments.There was no significant difference in maize grain yield and biomass between the CP and RC. However, grain yield and biomass were higher in the RC treatment. Based on the results of this study, it has been shown that increasing canopy cover reduces nutrient losses. In addition, the runoff, ridges soil,were able and to effectively check soil erosion.Item Effectiveness of Minjingu phosphate rock as a source of phosphorus for lowland rice production in selected soils of Tanzania.(Sokoine University of Agriculture, 2001) Mzee, OmariThis study was done to assess the effectiveness of Minjingu phosphate rock as a source of phosphorus for lowland rice production in selected soils of Tanzania. The study included soils from five sites for pot experiment and one of those sites was also used for a field experiment. Treatments tested were two sources of P namely MPR and TSP each applied at rales of 0, 40 and 160 mg P/kg, and 0, 20 and 60 kg P/ha under pot and field experiments, respectively. In both pot and field experiments, hosphorus released from all the treatments subsequent to flooding was determined by the Pi method and compared with P uptake, dry matter and grain yields of rice (Variety Kahogo-red). The relative agronomic effectiveness (RAE) of MPR relative to TSP was also determined. In the pot experiment, P application at high rate significantly increased drymatter yields by 33% to 498% relative to control. The performances of MPR and TSP were comparable in four soils (Lupilo, Ruvu-A, Ruvu-B and Kimani) whereas TSP did better than MPR in Michenga soil. Minjingu PR and TSP (high P application) were also comparable in improving P contents of plants. The RAE of MPR was high in Lupilo (95%), Michenga (82%), Ruvu-A (80) and Kimani (100%) soils while in Ruvu-B soil (68%) RAE was low. Extractable P after four weeks of flooding increased by 12 to 145% in four soils (Lupilo, Michenga, Ruvu-A and Kimani). In a field trial at Kimani, phosphorus application gave a nonsignificant increase in grain yield over the control and this was attributed to an appreciable increase in available P (from 5.14 to 10.10 mg/kg) after 42 days of flooding. Crop P concentration and uptake increased with application rates but the P sources (MPR and TSP) had comparable effects. Application of P did not increaseiii extractable P significantly. It is therefore concluded that MPR has the potential to supply P for rice production in Lupilo, Michenga, Ruvu-A and Kimani soils and others with similar properties.Item Response of rice (oryza sativa l.) to different phosphorus fertilizers in Lekitatu village, Meru district, Tanzania(Sokoine University of Agriculture, 2012) Massawe,Prosper InyasiABSTRACT A study was conducted to evaluate the response of rice to P and P use efficiency from MPR, Minjingu mazao and TSP fertilizers under irrigated rice (Oryza sativa L.) production in Lekitatu village. The fertility status of the soils and their suitability for rice production at two experimental sites were evaluated based on technical indicators of soil fertility. The major soil fertility limitations included low soil organic matter, low total nitrogen and medium available phosphorus hence the rice soils in Lekitatu village were categorized as of low fertility status and moderately suitable for rice production. Phosphorus was applied at rates of 0, 20, 40 and 60 kg P ha’1 as MPR, Minjingu mazao and TSP. Nitrogen was applied uniformly at a rate of 60 kg N ha’1 as urea to the MPR, Minjingu mazao and TSP treatments plots taking into account the 10% N contained in the Minjingu mazao fertilizer. The P fertilizers were broadcasted and incorporated into the soils before transplanting the rice seedlings and N was applied at two equal splits, namely at tillering and panicle initiation stages. The ranges in yield components between the control (0 kg P ha’1) and the highest levels of P (60 kg P ha’1) were 12-22, 12-19 and 12- 22 number of tillers per plant, 7.67-25.97, 7.67-26.83 and 7.67-30.20 tha’1 dry matter yields and 1.5-8.63, 1.5-9.23 and 1.5-10.43 tha’1 grain yields for MPR, TSP and Minjingu mazao, respectively. The P fertilizers applications increased rice yield components, N and P contents in the rice plants, residual soil P as well as plant PUE as the levels of P increased from 0 to 60 kg P ha’1 for all P sources. The yield components increased significantly (P<0.05) with increasing rates of P application. The increases were due to increased availability and uptake of plant nutrients particularly P. Based on the generated yields data, it was thus recommended that: Minjingu mazao at the rates of (40 to 60 kg P ha’1), MPR and TSP at a rate of 60 kg P ha'1, respectively could be adopted for increased and sustainable rice production in Lekitatu village.Item Response of rice (oryza sativa l.) to different phosphorus fertilizers in Lekitatu village, Meru district, Tanzania(Sokoine University of Agriculture, 2012) Massawe,Prosper InyasiA study was conducted to evaluate the response of rice to P and P use efficiency from MPR, Minjingu mazao and TSP fertilizers under irrigated rice (Oryza sativa L.) production in Lekitatu village. The fertility status of the soils and their suitability for rice production at two experimental sites were evaluated based on technical indicators of soil fertility. The major soil fertility limitations included low soil organic matter, low total nitrogen and medium available phosphorus hence the rice soils in Lekitatu village were categorized as of low fertility status and moderately suitable for rice production. Phosphorus was applied at rates of 0, 20, 40 and 60 kg P ha’1 as MPR, Minjingu mazao and TSP. Nitrogen was applied uniformly at a rate of 60 kg N ha’1 as urea to the MPR, Minjingu mazao and TSP treatments plots taking into account the 10% N contained in the Minjingu mazao fertilizer. The P fertilizers were broadcasted and incorporated into the soils before transplanting the rice seedlings and N was applied at two equal splits, namely at tillering and panicle initiation stages. The ranges in yield components between the control (0 kg P ha’1) and the highest levels of P (60 kg P ha’1) were 12-22, 12-19 and 12- 22 number of tillers per plant, 7.67-25.97, 7.67-26.83 and 7.67-30.20 tha’1 dry matter yields and 1.5-8.63, 1.5-9.23 and 1.5-10.43 tha’1 grain yields for MPR, TSP andItem Preliminary characterization of some streptomyces species from four Tanzanian soils and their antimicrobial potential against selected plant and animal pathogenic bacteria(World Journal of Microbiology & Biotechnology, 2000-05-02) Ndonde, M. J. M; Semu, EThis study was undertaken to characterize Streptomyces strains occurring in some soils of Tanzania as well as to evaluate their potential to synthesize antimicrobial compounds. Six main classes of isolates were observed according to the colour of aerial mycelium. These were gray, cream, blue, pink, red, and white. The gray colour class dominated. About 65% of the isolates produced soluble pigments of various colours while about 33% of the isolates did not produce any soluble pigments. Brown coloured soluble pigments dominated. About 57% of the isolates had spiral spore chains. Some Streptomyces isolates displayed strong (>30 mm inhibition zone), moderate (20±30 mm), or weak (<20 mm) antibiosis against the plant/animal pathogenic bacteria tested. Other isolates did not show any antibiosis against any of the test pathogens. The plant pathogens CMM IPO 542 (Clavibacter michiganensis ssp. michiganensis) and Xanthomonas vascatoria were inhibited by most of the Streptomyces isolates. Xanthomonas oryzae pv. oryzae and X. campestris were inhibited by the least number of the Streptomyces isolates. Most of the animal pathogens tested seemed to show resistance to the antibiotics produced by some of the Streptomyces isolates which had shown high activity against the plant pathogens.Item Evaluation of the impact of alternative wheat residue and water management on soil properties and soybean yield in a wheat-soybean double-crop system, Eastern Arkansas(University of Arkansas, 2008-12) Amuri, NyambililaLong-term agricultural sustainability requires evaluation of agricultural management practices that may improve and sustain soil quality and crop productivity over time. The objective of this study was to determine the 6-yr effects of tillage [conventional (CT) and no-tillage (NT)], wheat residue burning (bum and no bum), residue level (low and high), and 3-yr irrigation (irrigated and dry-land condition), on soybean [Glycine max (L.) Men-.] yield, soil physical and chemical properties in the top 10 cm, and weed population diversity in a wheat [Triticum aestivum (L.)]-soybean double-crop production system. A field experiment was conducted from fall 2001 through fall 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 at a greater magnitude under NT (1.22 to 1.35 g cm'3) than CT (1.19 to 1.26 g cm*3) during the first 3 years, but declined at a similar rate in both tillage treatments after the third year. Irrigation increased soil pH (0.2 pH unit yr*1), Mehlich-3 extractable soil Mg (55.1 kg Mg ha*1 yr*1), and total C contents (0.11 kg C m*2 yr*1) compared to dry-land condition which had no pH change, but had less increase of extractable Mg (36.6 kg Mg ha*1 yr*1), and total C content (0.04 kg C m*2 yr*1). Soil organic matter (SOM) increased over time in all treatment combinations. Total C (TC) increased at a greater rate in the no bum (0.077 kg C m*2 yr*1) and high-residue-level (0.073 kg C m*2 yr*1) than in the bum (0.051 kg C m*2 yr*1) and low-residue-level (0.054 kg C m*2 yr*1) treatments. The total weed species density was greater under CT (513 plants m*2) than under NT (340 plants m*2) early in the soybean growing season in 2006, but did not differ between tillage treatments in 2007. Perennial weed density was greaterunder bum (99 plants m"2) than no bum (59 plants m’2) in 2006, and in 2007, was greater under NT than CT but unaffected by bum. Retaining crop residues and herbicide application reduced the density of all weed species, grass, and broadleaf weed species. Tillage, burning, and residue level generally did not affect soil penetration resistance in the top 0.20-m in 2003 and in 2006, but soil cone index (CI) was consistently lower under bum than no bum at all depth below 0.20 m. The CI at the 0.05-m depth increased by 35% after 4 years compared to after 1 year of NT soybean. Soybean yield differed over years of the trials. Soybean yield declined during the first 3 years, but increased over the subsequent 3 years in all treatment combinations. Economic analysis showed that management practices with NT will likely be more profitable than the traditional CT practice even when the fertilizer and diesel costs continue to increase. Therefore, NT and non-burning with any residue level have great potential to improve soil quality, reduce weed pressure in the soybean growing season, and maintain profitability in the wheat soybean double-crop production system.