Thesis

Optimizing nitrogen and Phosphorus Management for beard wheat (Triticum Aestivum ) Yield and Nutrient use efficiency in Nitisols of Wadla District, North Wollo, Ethiopia

2025-07-31T07:17:54Z

Optimizing nitrogen and Phosphorus Management for beard wheat (Triticum Aestivum ) Yield and Nutrient use efficiency in Nitisols of Wadla District, North Wollo, Ethiopia Kassa Sisay Optimizing Nitrogen and Phosphorus Management for Bread Wheat (Triticum aestivum) Yield and Nutrient Use Efficiency in Nitisols of Wadla District, North Wollo, Ethiopia Kassa Sisay, 1 Yihenew G.Selassie 2 , and Birru Yitaferu 3 1. Amhara Agricultural Research Institute, Sirinka agricultural Research Center 2. Stichting Wageningen Research Ethiopia (SWR-E) Wageningen University and Research 3. Senior Soil Scientist and Researcher Coordinator, CapSha Fertilizer DST Project Ethiopian Institute of Agricultural Research (EIAR) Soil fertility depletion, particularly nitrogen and phosphorus, is a major constraint to wheat productivity in Ethiopia, influencing crop yields and food security. A field experiment was conducted to determine the optimum nitrogen and phosphorus rates for wheat yield, nutrient uptake, nutrient use efficiency, and economic returns in Wadla District, Ethiopia during the 2023/2024 cropping season. The experiment was arranged in a factorial randomized complete block design with three replications. The treatment was comprised of four N levels (46, 92, 138, and 184 kg ha⁻¹) and four P 2 O 5 levels (23, 46, 69, and 92 kg ha⁻¹). Yield and yield component parameters, plant sample for uptake, and use efficiency were collected. The collected data were analyzed using SAS (version 9.0), and mean separation was carried out using the Duncan Multiple Range Test at a 5% significance level. The results showed that the nutrient levels significantly influenced wheat growth, yield components, nutrient uptake, nutrient use efficiency, and economic returns. The highest performance economically yields and yield-related parameters were recorded with the combined application of 138 kg N ha⁻¹ and 69 kg P₂O₅ ha⁻¹, resulting in biomass and grain yields of 7.8 t ha⁻¹ and 3770 kg ha⁻¹, respectively. The maximum biological grain (3,840.0 kg ha -1 ) and biomass (7.91 tons ha-1) yields were recorded at 138 kg N ha⁻¹ with 92 kg P 2 O 5 ha⁻¹. Total nitrogen uptake was high for 138 kg N ha⁻¹ (82.52 kg N ha⁻¹), while phosphorus uptake was high for 69 kg P 2 O 5 ha⁻¹ (18.42 kg P ha⁻¹), with uptake efficiency decreasing at higher rates. Agronomic use efficiency, partial factor productivity, and recovery efficiency also reached their highest values at lowest to moderate N and P levels. Partial budget analysis indicates that the applications of 138 kg N ha⁻¹ with 69 kg P 2 O 5 ha⁻¹ gave the highest net benefit 258,954.2 ETB ha⁻¹ with marginal ret of return 5825.3 %. Therefore, the application of 138 kg N ha⁻¹ and 69 kg P 2 O 5 ha⁻¹ is recommended for maximizing wheat yield, economic returns and also enhancing nutrient uptake and nutrient efficiency in Wadla and similar agroecological areas. Further research should be done on the long-term residual effect of P and nutrient efficiency through regular soil testing and monitoring to enhance nutrient uptake while minimizing environmental footprints.

Effect of Inoculation and Soil Amendments on Nitrogen Fixation and Yield of Haricot Bean (Phaseolus Vulgaris L.) in North Western Ethiopia

2025-04-04T08:06:24Z

Effect of Inoculation and Soil Amendments on Nitrogen Fixation and Yield of Haricot Bean (Phaseolus Vulgaris L.) in North Western Ethiopia Fekadu Tiruneh Legume-based cropping systems are regarded as a sustainable method to reduce the need for external nitrogen fertilizers. Haricot bean (Phaseolus vulgaris l.) is one of the most economically important pulse crops cultivated in north western Ethiopia. However, the average yield reported remains significantly below its potential. This is partly due to poor soil fertility management and inappropriate agronomic packages considered to be among the major production constraint. Hence, this experiment was conducted to determine the effect of inoculation and soil amendments on nitrogen fixation and Yield of haricot bean in north western Ethiopia. The experiment was conducted in Koga irrigation scheme during two cropping rainfed season (2021-2022). Treatments consisted of three rates of nitrogen (0, 10 and 20 kg ha-1 ),two rates of lime (0 and 2ton ha-1 and three rhizobia strains (0, HAMBI3570 and HAMBI3562), SER-119 haricot bean variety in factorial combinations was laid out in a randomized complete block design with three replications to evaluate their effects on soil physicochemical properties and haricot beans yield and yield components. Data on soil, phonological, nitrogen fixation, yield and yield components were collected and analysed by SAS 9.4 software. The result showed that the interaction effect of different soil amendments had a significant variation in all treatments. Thus, soil physio-chemical properties significantly (P<0.001) varied on pH, EA, OC, TN, EC, CEC, SIN, AV.P and agrocnomic parameters of days to 50% flowering, days 90% maturity, plant height, number of primary branches, total number of nodule, effective number of nodule, percent of nodule effectiveness, number of pods per plant, number of seed per pod, hundred seed weight, leaf area per plant, leaf area index, grain yield, bimass yield, harvest index, straw yield. The control plot soil physco-chemical properties at the main cropping season in experimental site indicated that soil texture=clay,bulk density=1.27g/cm-3 , Total porosity=52.2%, Soil moisture content soil=22.33%, pH=5.17, exchangeable acidity=2.65 cmol(+)kg-1 ), Organic Carbon =1.63%, total nitrogen=0.186%, Eectrical conductivity=0.050 dS/m, CEC=24.25 cmol (+) kg-1 ), SIN=60.83 mg kg-1 , Available P=9.14ppm, were recorded. The results of the study shows combined application of lime, starter nitrogen and rihizobia application increases total porosity by 9.05%, soil moisture content by 9.31%, soil pH by 0.96 units, organic carbon by 0.88%, total nitrogen by 0.046%, CEC by 14.91 units and available P by 22.86 ppm and decreased bulk density by 0.24g/cm-3 , exchangeable acidity by 2.4 cmol(+)kg-1 ) and electrical conductivity by 0.018 dS/m compared to the control. Moreover, the combined application of these treatments significantly (p<0.001) increased plant xix height, number of primary branches, total number of nodule, effective number of nodule, percent of nodule effectiveness, number of pods per plant, number of seed per pod, hundred seed weight, leaf area per plant, leaf area index, grain yield, biomass yield, harvest index, straw yield. Similarly, the combined application of lime 2 ton ha-1+20 kg ha-1 + starter nitrogen+HAMBI3570 increased Haricot bean yield by 510.6% compared to control. However, the economic analysis showed that the combination of lime 2 ton ha-1+20 kg ha-1 starter nitrogen + HAMBI3570 gave the highest netbenefit (259,426.2 ETB ha-1 ) with an acceptable MRR of 25,297.28%. Thus, it can be concluded that the combination application of lime 2 ton ha-1+20 kg ha-1 starter nitrogen+HAMBI3570 to be proved superior with respect to economic advantage in the North western Ethiopia.

Soil Bunds, Cover Crops, and Acacia Decurrens Plantation Practices Influence Soil Erosion, Soil Moisture, and Crop Yield in the Abbay Basin, Ethiopia

2025-04-04T08:01:16Z

Soil Bunds, Cover Crops, and Acacia Decurrens Plantation Practices Influence Soil Erosion, Soil Moisture, and Crop Yield in the Abbay Basin, Ethiopia Simeneh Demissie Land degradation due to accelerated soil erosion is a major socio-economic development and environmental sustainability threat in the highlands of Ethiopia. To reverse these problems several types of sustainable land management (SLM) practices have been implemented in the past 50 years. The interventions were critical to reduce runoff and soil loss and improve soil moisture and land productivity. The study focuses on evaluating the impact of biophysical land management practices on soil erosion and soil moisture in the Guder and Aba Gerima watersheds. Runoff plots were established in the three selected SLM technologies (5 plots on soil bund spacing [27.2, 12.7, 7.87, and 5.45 m], 12 plots on 3 cover crops [bitter lupin, vetch, and sweet lupin], and 3 plots on Acacia decurrens [AD] plantation). From each plot daily runoff and soil loss data were measured. Composite soil samples were collected from the cover crop (CC) and AD plots for pH, organic carbon (OC), total nitrogen, and available phosphorus analysis. For soil moisture analysis 1080 and 366 disturbed soil samples were collected at depths of 0 to 0.5 m and 0 to 0.6 m (at 0.1 m intervals of soil profile) from CCs and soil bund (SB) plots, respectively. The results revealed that SBs and CCs substantially reduced surface runoff. Soil bunds were more effective in reducing runoff than CCs and AD. Year 3 and 4 AD plantations were the least in reducing runoff loss even lower than the control plots. Slope length between consecutive SBs also affects the efficiency of SBs in reducing runoff loss (the narrowest the most efficient). The narrowest SBs, bitter lupin CC, and year 1 AD (better understory vegetation) show the best performance in reducing soil loss. Wider SB spacing, low biomass-producing CCs, and older AD (low understory vegetation and water infiltration) have less efficiency in reducing soil loss but were better than the control. The average seasonal soil water significantly (P < 0.05) decreased with increased SB spacing. In this study, CCs had no substantial effect on soil water content. Cover crop treatments significantly improved OC, total nitrogen, available phosphorus, and dry organic biomass addition. Similarly, OC, total nitrogen, and available phosphorus were improved in AD plots compared to the control. The soil fertility improvement due to SLM practices affects crop yields positively. Adopting optimum SB spacing and fast-growing leguminous CCs (bitter lupin) provides the best economic and environmental benefits. However, further studies will be required to prove the integration impacts of physical with biological SLM practices in different biophysical settings.

Optimization of Nitrogen and Phosphorus Nutrients Forenhanced Bread Wheat (Triticum Aestivum L) Productiononthenitisols of Yilmana Densa District Northwestern Ethiopia

2025-04-04T07:55:11Z

Optimization of Nitrogen and Phosphorus Nutrients Forenhanced Bread Wheat (Triticum Aestivum L) Productiononthenitisols of Yilmana Densa District Northwestern Ethiopia Bitewelegn Kerebeh Nitrogen (N) and phosphorous (P) are the two major yield limiting plant nutrients inEthiopia. Existing NP rates for the production of cereal crops, including wheat, are veryoldand critically need revisiting and updating the economic and biological optimumrates. Thus, this research was conducted to determine the economical optimum rate of NandPforbread wheat (Triticum aestivum L.) in 2023 rainy season in the Nitisols of YilmanaDensadistrict, Northwest Ethiopia. The treatment consisted of five levels of nitrogen(69,115,161,207 and 253 kg ha -1) that were factorially combined with three levels of P2O5(46, 69 and 92 kg ha -1). A pilot treatment with no N and P was also added as a control toevaluate the overall performance of wheat under no fertilizer input. TAY breadwheat variety, which is widely adapted to the study area, was used as a test crop. The treatmentswere arranged in a randomized complete block design (RCBD) with three replications. Disturbed and undisturbed soil samples were collected before treatment application. Thedata were analyzed using SAS version 9.0 and treatment means were separated usingLSDat P ≤ 0.05. The result revealed that N and P2O5 significantly (P < 0.05) increasedgrainyield, straw yield, and other yield components of the bread wheat. The lowest grain, strawyields (349.2,446.8 kg ha -1 , respectively) were recorded from the control. The combinationof 207 kg N and 69 kg P2O5 ha -1 resulted in the highest grain and straw yields (3737, 3606kg ha -1 , respectively) with maximum grain N (120.95 kg ha -1) and P (6.60 kg ha -1) uptakescompared to the other treatments. The agronomic ef iciencies of N and P decreasedas theirrates increased. Finally, 207 N combined 69 P2O5 kg ha -1 is economically feasible withanet benefit of (208,612.1 ET Birr) and 898.3% MRR and is therefore recommendedfor theproduction of bread wheat in the Nitisols of Yilmana Densa district. This was preferredtosoil nutrients are variable in spatial, so site-specific recommendation of fertilizerapplication to balance N and P nutrients are beneficial for bread wheat production.