Fertilizer Rates Research Articles

Optimizing rocket (Eruca sativa L.) productivity: blended fertilizer rates and inter-row spacing

ABSTRACT Rocket (Eruca sativa L.) is a crucial herbaceous crop, but a lack of improved agronomic practices constrains its production in Ethiopia. This field experiment aimed to determine the optimum rate of blended NPS fertilizer and inter-row spacing for high biomass and leaf yield. The study utilized a factorial design, with five blended NPS fertilizer rates (0, 50, 100, 150, and 200 kg ha− 1) and three inter-row spacings (10, 20, and 30 cm) arranged in a randomized complete block design with three replications. The growth and yield traits were significantly (p < .05) influenced by the interaction between fertilizer rates and inter-row spacing. The highest total leaf yield (62,481 kg ha− 1) was achieved with 200 kg ha− 1 NPS and 30 cm inter-row spacing. Additionally, the shortest time to maturity (ranged from 28-31 days) was recorded with the same treatment. Thus, applying 200 kg ha− 1 NPS combined with 30 cm inter-row spacing resulted in the highest marketable yield and net benefit ($19,109.50 ha− 1) in the study area.

Evaluation of carrot (Daucus carota L.) varieties for growth and yield as affected by NPSB fertilizer rates in Gondar district, Ethiopia

Evaluation of carrot (Daucus carota L.) varieties for growth and yield as affected by NPSB fertilizer rates in Gondar district, Ethiopia

Effects of combined application of nitrogen, phosphorus, and potassium fertilizers on seed yield, seed quality and economic returns of Elymus nutans in alpine region.

The Qinghai-Tibetan Plateau (QTP), one of the most important ecological regions in the world, is experiencing a decline in ecological function as a result of severe grassland degradation. Elymus nutans is one of the ecological grass species for restoring degraded grasslands in QTP. The seed yield and seed quality are often limited by soil nutrients in QTP, so it is very important to optimize the application rates of fertilizer for E. nutans seed production. In this study, a "3414" fertilization experiment (nitrogen: 0 ~ 225kg N ha- 1; phosphorus: 0 ~ 180kg P2O5 ha- 1; potassium: 0 ~ 135kg K2O ha- 1) was established in the third year of planting E. nutans seed field based on the soil nutrient supply situation in the planting area to explore the effects of combined application of N, P and K fertilizers on the seed yield and seed quality of E. nutans. The results showed that the balanced application of N, P and K fertilizers significantly improved the seed yield, seed quality and seed vigour of E. nutans. The seed yield of E. nutans was regulated by the seed yield components. Under different fertilization treatments, the number of fertile tillers and thousand kernel weight had a greater contribution to seed yield, followed by the number of spikelets per panicle. Compared to the no fertilization treatment, the combined application of N, P, and K fertilizers increased the seed yield of E. nutans by 23.05%-90.49%. The seed size, seed nutrient content, germination percentage and seedling growth of E. nutans were positively affected by the combined application of N, P and K fertilizers. The seed vigour of E. nutans increased by 38.23%-89.85% compared to the no fertilizer treatment. Fertilizer application promoted seed nutrient storage and increased seed size thereby promoting seed germination and seedling growth. The crude protein, soluble sugar and starch content of E. nutans seed increased by 9.70%-54.05%, 6.70%-25.70% and 4.31%-35.88%, respectively. Nitrogen fertilizer had a greater effect on seed yield and seed quality of E. nutans than phosphorus and potassium fertilizers. The balanced nitrogen, phosphorus and potassium fertilizers at an application rate of 150kg N ha- 1, 120kg P2O5 ha- 1, 90kg K2O ha- 1 in the planting area of QTP was found to be the optimum fertilization amount for increasing seed yield, seed quality and net income. This study provides theoretical evidence and certain practical suggestions for sustainable forage seed production in alpine regions of QTP.

Assessment of the combined effects of organic manure and NPK (17-17-17) on growth and yield of carrots in Rwanda

Carrot (Daucus carota L.) is one of the most important vegetable crops grown in many parts of Rwanda. However, its yield and growth are still low among many smallholder farmers partly due to limited knowledge on proper fertilizer use and application. To address this issue, the study was conducted to assess the effect of combined application of organic manure with different rates of NPK (17-17-17) on growth and yield of carrots in Rwanda. Understanding the impact of organic manure and NPK fertilizers on carrot growth and yield can help farmers optimize production, and enhance food security and economic development in the region. A field experiment was undertaken in season 2022-2023 in three agro-ecological zones (AEZs) in three different provinces of Rwanda namely, Huye (Southern province), Bugesera (Eastern) and Rubavu (Western) districts. Eight treatments were arranged in a randomized complete block design (CRBD) with three replications. Each of the eight treatments received a uniform application of 25 tons per hectare of organic manure. Additionally, inorganic fertilizers (specifically NPK 17-17-17) were introduced in varying quantities, except for the control plot(T0), which did not receive any NPK. The treatments (T) were arranged as follows: T0 (Control) = 0 kg/ha, T1= 50kg/ha, T2= 100 kg/ha, T3=150 kg/ha, T4=200 kg/ha, T5=250 kg/ha, T6=300 kg/ha and T7= 350 kg/ha. Data collected from the experiment were subjected to analysis of variance (ANOVA) using R Studio. The analysis aimed to evaluate the impact of the different treatments on the growth and yield of carrots in the three agroecological zones (AEZs) represented by the Huye, Bugesera, and Rubavu districts. Results showed variations in carrot growth and yield based on fertilizer rates across all AEZs. Among the treatments, Treatment T7, receiving 350 kg/ha of NPK, exhibited a significant increase in the number of leaves and plant height compared to other treatments. Conversely, the control plots (T0) exhibited the lowest plant height and number of leaves across all AEZs. Similarly, the T7 also resulted in the highest carrot yield of 7.1 kg, outperforming all other treatments. In contrast, the control group (T0) exhibited the lowest yield of 3.3 kg. These findings suggest that combining 25 t/ha of organic manure with 350 kg/ha of NPK can significantly boost carrot production in various regions of Rwanda. The use of organic manure combined with NPK fertilizers can provide essential nutrients to the carrots, promoting their growth and yield. This information can be valuable for carrot farmers in the three AEZs of Rwanda, as it offers a practical approach to improving carrot production and increasing yields. Key words: Carrot, agro-ecological zone, fertilizer, growth and yield, Rwanda

Impact of nutrient management on physiological processes, biochemical properties, and

Aim. The purpose of the study was to determine the effect of different fertilizers and their aftereffects on the biometric and biochemical parameters of plants, the formation of yield, and the quality of beetroots. Methods. Field, statistical, calculation, analytical, and laboratory research methods were used in the study (dry matter (thermogravimetric method), total sugar (titration with red blood salt), ascorbic acid (according to Tillmans), nitrates (potentiometric method using nitrate-selective electrodes)). Results. The use of microbial preparations both separately and in the aftereffect of organic fertilizers led to an increase in the chlorophyll content in beetroot leaves (up to 7.36-9.14 mg/kg). The yield of table beetroots at the level of 52.6-57.6 t/ha is provided by mineral and organo-mineral fertilization systems, the aftereffect of 21 t/ha of manure, and a combination of organic fertilizers and microbial preparations. Using a complex of microbial preparations (Groundfix, Azotophyte, Organic Balance) to optimize the nutrition of beetroot plants increased the yield by 19 %. The values of most biochemical parameters in the products decreased with the increase in their yield. The use of high norms of mineral fertilizers or the localization of their administration conditioned the increase in the content of nitrates (1,490-2,349 mg/kg). With the increase in yield, a decrease in some biochemical parameters of beetroots (dry matter, total sugar, and ascorbic acid content) was observed. The use of high rates of mineral fertilizers or localization of their application led to an increase in the content of nitrates (1,490-2,349 mg/kg). Different fertilization systems for table beetroot provided the additional profit at the level of UAH 46.4-142.9 thousand/ha and the profitability of 42.6-69.6 % while reducing production costs to UAH 4.72-5.61 per one kg. Conclusions. The practical value of the research was determining the effect of different fertilization systems on a number of physiological processes and productivity of beetroot plants, the biochemical composition of root crops, and accumulation of nitrates in them, which allowed us to recommend the organo-mineral and biological fertilization systems with a complex of microbial preparations. In further research, it is important to establish the efficiency of alternative nutrition optimization systems with the combined use of humic and green manure fertilizers, and microbial preparations of various directions.

Combined Mineral and Organic Fertilizer Application Enhances Soil Organic Carbon and Maize Yield in Semi-Arid Kenya: A DNDC Model-Based Prediction

The application of mineral fertilizers can effectively enhance crop yields. However, this potential benefit may be diminished if the use of mineral fertilizers leads to a substantial decline in soil organic carbon (SOC) and an increase in soil greenhouse gas (GHG) emissions. This study aimed to determine the optimal fertilizer combinations and rates for improving SOC and maize yield while reducing GHG emissions in the semi-arid uplands of Kenya. Data were collected from five different fertilizer treatments (N50, N100, N150, N100+manure, and N100+straw) compared to a control (N0) in a long-term experimental field, which was used to run and validate the DNDC model before using it for long-term predictions. The results showed that the combination of mineral fertilizer and straw resulted in the highest SOC balance, followed by that of fertilizer and manure. All fertilized treatments had higher maize grain yields compared to low-fertilizer treatment (N50) and control (N0). Daily CO2 fluxes were highest in the treatment combining mineral fertilizer and manure, whereas there were no significant differences in N2O fluxes among the three tested treatments. The findings of this study indicate that the judicious application of mineral fertilizer, animal manure, and straw has great potential in enhancing SOC and maize yields while reducing GHG emissions, thereby providing practical farming management strategies in semi-arid Kenya.

Enhancing Productivity of Bread Wheat (Triticcum aestivum L.) Through Integrating Vermicompost and N fertilizer in Meskan District, Central Ethiopia

Soil fertility management is very crucial to optimize and sustain agricultural production so as to secure food for the current generation as well as the generation to come. Ethiopia is one of the food insecure countries in Sub-Saharan Africa. The country is striving to secure food through optimizing and sustaining crop production. The purpose of the study was to examine the combined effect of organic (vermicompost) and inorganic (nitrogen) fertilizer rates on growth and yield of bread wheat in Meskan distric, Central Ethiopia. The experiment used four levels of vermicompost (0, 1, 1.5, and 2 t ha-1) and Nitrogen (0, 50 percent recommended rate of N (RN), 75 percent RN, and 100 percent RN) in a factorial combination in RCBD design with three replications using a wheat variety (Kekeba) as the test crop. The result of the study asserted that yield and yield-related traits were significantly different at P &lt; 0.05. The treatment of 2 t ha-1 vermicompost + 75 percent of RN produced the maximum grain yield (2773 kg ha-1); while the control produced the lowest grain yield (1062 kg ha-1). Combined application of organic fertilizer (vermicompost) and inorganic fertilizer (N) optimizes wheat production in the study area. Sole application of organic fertilizer (vermicompost) and inorganic fertilizer (N) would not bring optimum production of wheat. Therefore, combined application of organic and inorganic fertilizers could have great contribution towards food security for countries like Ethiopia with low fertilizers input user and high food insecurity level.

Nitrogen Management Utilizing 4R Nutrient Stewardship: A Sustainable Strategy for Enhancing NUE, Reducing Maize Yield Gap and Increasing Farm Profitability

The imbalanced use of fertilizers, particularly the inefficient application of nitrogen (N), has led to reduced nitrogen use efficiency (NUE), lowered crop yields and increased N losses in Nepal. This study aimed to enhance yields, NUE and farm profitability by optimizing N fertilizer rates, application timing and methods through multilocation trials and demonstrations. In 2017, 57 field trials were conducted in two mid-hill districts using a completely randomized block design. The treatments included control (CK), NPK omission (N0, P0 and K0), variable N rates (60, 120, 180 and 210 kg N ha−1) and top-dressing timings (120 kg N ha−1 applied at knee height and shoulder height, V6, V10 and V8 stages). A full dose of recommended P (60 kg ha−1) and K (40 kg ha−1) were applied at planting, while N was top-dressed in two equal splits at knee-height and shoulder-height growth stages for P and K omission treatments, as well as for treatment with variable N rates. Grain yields responded quadratically, with optimum N rates ranging from 120 to 180 kg ha−1 across the districts. N applied at 120 kg ha−1 and top-dressed at V6 and V10 increased maize yield by 20–25%, partial factor productivity of nitrogen (PFPN) by 12%, agronomic efficiency of nitrogen (AEN) by 21% and gross margin by 10% compared to conventional knee and shoulder height application. In 2018 and 2019, fertilizer BMPs, including V6 and V10 top-dressing and the urea briquette deep placement (UDP) were demonstrated on 102 farmers’ fields across five mid-hill districts to compare their agronomic and economic significance over traditional farmers’ practice (FP). UDP, validated in 2018 field trials, increased yields by 34% (8.8 t ha−1) and urea top-dressing at V6 and V10 increased yield by 33% (8.7 t ha−1) compared to FP (5.8 t ha−1), reducing the average yield gap by 3.0 t ha−1. Moreover, the gross margin was increased by 39% (V6 and V10) and 40% (UDP) over FP. The findings highlight the need for widespread adoption of fertilizer BMPs to close the yield gap and maximize profitability with minimal nitrogen footprint.

Effects of Different Rates of Nitrogen Fertilisation and Biological Preparations to Increase Nitrogen Use Efficiency on Yield Structure Elements in Maize

The soil used for the field experiment was PLb-g4 Endohipogleyic Eutric Planasol. The research aimed to investigate the effects of different nitrogen fertilisation rates and biological preparations on yield structure elements and partial factor productivity of nitrogen in maize (Zea mays L.) grown for grain production. The factors studied were Factor A—nitrogen (N) fertiliser rates: (1) 100 kg ha−1, (2) 140 kg ha−1, and (3) 180 kg ha−1, and Factor B—use of biofertilisers: (1) no biological preparations (BP) used, (2) biological preparation (AB)—nitrogen bacteria Paenibacillus polymyxa (1.0 L ha−1), (3) biological preparations (AB + C)—nitrogen bacteria Paenibacillus polymyxa (1.0 L ha−1) and cytokinin, and (4) biological preparations (AB + H)—nitrogen bacteria Paenibacillus polymyxa (1.0 L ha−1) and humic acids. The research showed that the yield of maize grain was significantly increased not only by increasing the rates of nitrogen fertilisation but also by using biological preparations. The highest maize grain yield (11.5 t ha−1) was obtained in 2020 using N180 fertilisation, in combination with biological preparations AB + H. In all cases, the biological preparations and their combinations significantly increased the maize grain yield compared to the control field (no use of BP). The biological preparations in combination with N significantly increased the weight of 1000 grains and thus the grain yield per plant. The highest maize grain yield per plant (154.6 g) was obtained in 2020 using N180 fertilisation, in combination with biological preparations AB + H. In most cases, positive, strong, very strong, and statistically significant correlations were observed between the different rates of nitrogen fertilisation and the indicators studied: r = 0.76–0.94 (p &lt; 0.01, p &lt; 0.05). No statistically significant correlation was found between nitrogen fertilisation rates and the number of grains per cob (p &gt; 0.05). The highest partial factor productivity of nitrogen fertiliser (92.0 kg of maize kg−1 of N) was obtained in 2020 using N100 fertilisation, in combination with AB + H. Increasing the nitrogen fertiliser rates and not using biological preparations resulted in a decrease in the partial factor productivity of nitrogen fertiliser.

Effect of Urea Fertilizer Rate on Growth and Yield Components of Sorghum (Sorghum bicolor L.) under Rain – fed Conditions, in North Kordofan, Sudan

Effect of Urea Fertilizer Rate on Growth and Yield Components of Sorghum (Sorghum bicolor L.) under Rain – fed Conditions, in North Kordofan, Sudan

Field Evaluation of Fertilizer Rates for the Best Establishment of Young Eucalyptus gunnii Trees

Field Evaluation of Fertilizer Rates for the Best Establishment of Young Eucalyptus gunnii Trees

Economic value of dual‐purpose cowpea as affected by variety, fertilizer, and environment

AbstractAcross the semiarid regions of West Africa, cowpea (Vigna unguiculata (L.) Walp) varieties grown by farmers are either grain‐ or forage‐only, and often fields are not fertilized. Information regarding profitability of dual‐purpose over traditional varieties and fertilizer application in cowpea production system is limited. The main objective of this study was to quantify the economic value of newly released dual‐purpose and forage cowpea varieties and fertilizer inputs across the Senegalese peanut basin. This field study was conducted across three locations in Senegal (Bambey, Boulel, and Darou Mousty) in 2021 and 2022. Treatments were 20 cowpea varieties in the main plot and two levels of fertilizer (an unfertilized control and fertilized) in the subplot. Cowpea varieties E‐BC4STR1, E‐BC4STR5, E‐BC4STR11, Kelle, and Melakh had relatively greater grain yields (average 429–474 kg ha−1) in all environments. Forage varieties 66‐35F and 58‐74F produced the most forage (average 2353 and 1717 kg ha−1) yields across environments. Fertilizer‐NPK application increased grain yield by 22%–40% in most environments. Unlike grain yield, varietal effects on forage yields occurred only with fertilizer application. Dual‐purpose cowpea varieties E‐BC4STR1, E‐BC4STR2, E‐BC4STR5, and E‐BC4STR11 had a stable, significant economic value in our study compared with grain‐only variety Yacine (traditional variety) or forage variety 66‐35F. Fertilizer‐NPK increased net revenue in four out of six environments. We conclude that using dual‐purpose cowpea varieties provided significant economic advantage over traditional varieties, and application of fertilizer further increased the economic value. However, further studies are needed to determine the economically optimal fertilizer rate.

Fertilization Induced Soil Microbial Shifts Show Minor Effects on Sapindus mukorossi Yield.

Fertilization can improve soil nutrition and increase the yield of Sapindus mukorossi, but the response of soil microbial communities to fertilization treatments and their correlation with soil nutrition and Sapindus mukorossi yield are unclear. In order to investigate the characteristics of soil physicochemical qualities and the bacterial community, we carried out a field experiment comparing various quantities of nitrogen (N), phosphorus (P), and potassium (K) fertilizers to the unfertilized control treatments and the yield of Sapindus mukorossi in raw material forests in response to different applications of fertilizers and to try to clarify the interrelation among the three. Results showed that (1) there are significant differences in the effects of different fertilization treatments on the soil properties of Sapindus mukorossi raw material forests. The increase in the application rates of nitrogen or phosphorus fertilizers significantly reduced the soil pH value. (2) Compared with control, the α-diversity of bacterial communities was significantly lower in N3P2K2 and N1P1K2 treatments. Among the dominant groups of soil bacteria at the phylum level, the relative abundance of Chloroflexi showed an increase and then a decrease trend with the increase in N application. The relative abundance of Firmicutes, Bacteroidota, and Fusobacteriota was positively correlated with the application of P and K fertilizers, while the relative abundance of Acidobacteriota and Verrucomicrobiota decreased with the increase in P and K fertilizers. (3) The N2P2K2 treatment produced the highest sapindus yield (1464.58 kg/ha), which increased by 258.67% above the control. (4) Redundancy analysis (RDA) showed that the primary determinants of bacterial community structure were soil pH, total K, and effective P concentration. (5) Structural equation modeling (SEM) showed that soil nutrient content was the main direct factor driving the yield of Sapindus mukorossi, whereas the bacterial community attributes (e.g., diversity and structure) had minor effects on the yield. In summary, the rational use of formulated fertilization can change the bacterial community structure, improve the bacterial diversity, and increase the soil nutrient content, with the latter exerting a significant effect on the improvement of the yield of Sapindus mukorossi.

Impact of Combined Vermicompost and Inorganic Fertilizers on Bread Wheat Yield, Yield Component and Soil Properties in Sinana District, Bale Highlands, Ethiopia

A field experiment was made to evaluate the effects of organic and inorganic fertilizers on the growth and yield of wheat and soil chemical properties. The study was conducted for two consecutive cropping seasons (2023-2024) on farmers’ fields in the Sinana district of Oromia National Regional State. Therefore, this study has attempted to evaluate the effect of the integrated use of vermicompost and inorganic fertilizer on bread wheat production and soil fertility improvement in the study area. Fertilizer source organic Sources of nutrients both included (vermicompost) and inorganic fertilizer (urea and NPS) were used in the integrated form. These treatments consist of: T1 = Control (no input) T2 = Recommend NP, T3 =25% RVC + 75% N + Rec P, T4 =100% RVC + rec P, T5 =50% RVC + 50% N + rec P and T6 =75% RVC + 25% N + Rec P. The experiment was a randomized complete block design with three replications. Soil sampling and agronomic data on wheat grain yield and yield components were collected. Accordingly, the highest mean grain yield (5403.67kgha-1) was recorded from the plot of T2 (Recommended rate from inorganic) flowed by (5186.00 kgha-1) was recorded from T3 (25% RVC + 75% N + Rec P) while the lowest grain yield (2637.67 kgha-1) was recorded from control plot. The partial budget analysis was performed for alternative uses of integrated organic and inorganic fertilizer applications for bread wheat production. The results showed that the application of integrated vermicompost with recommended rates of inorganic NP significantly increased the yield and yield components. It can be concluded that the application of integrated vermicompost and recommended rate of inorganic NP fertilizers (25 % Equivalent N from + 75 % N + Rec P is desirable) based on environmental sustainability for future productivity. This experiment has to be repeated over seasons and locations to make conclusive recommendations for the study area.

Effect of NPSB Fertilizer Rates and Varieties on Yield Components and Yield of Bush Type Common Bean at Bako, Western Oromia Ethiopia

Information barrier on the use of fertilizer on common bean is a major problem on production and productivity of common bean at western Oromia Ethiopia. To overcome the problem the experiment was conducted to identify effect of NPSB fertilizer application rate and common bean varieties to produce better seed yields. A field experiment consisting of the combination of three common bean varieties and four fertilizer application rates were employed Randomized Complete Block in factorial arrangements with three replications. Data on phenological, yield components and yield were collected and analyzed. The results of the study revealed that significantly the highest number of pods per plant (18.7). The highest seed yield was obtained at the highest combined rates (150kg NPS ha-1 + Nasir variety (2199kg ha-1) while the lowest seed yield (710kg ha-1) was obtained from Loko variety treated without application of NPSB. Therefore, based on net benefit (77872 ETB) analysis and the value of MRR% (2,294.94) of the farmers could be used Nasir variety combined with 150 to obtain maximum yield and 100kg ha-1 to attain optimum yield.

The role of nano fertilizers and compost in improving agricultural soil properties and their impact on faba bean productivity

The research aimed to assess the effects of NPK nano-fertilizers and compost, with or without NPK mineral fertilizers, on soil properties and the productivity of local beans. The results showed that when nano-fertilizers and compost were applied, there were increases in plant height (cm), number of branches per plant, number of pods per plant, pod weight (ton/acre), and 100-seed weight compared to when mineral fertilizers were used at different concentrations. The interaction of NPK nano-fertilizers with organic manure, along with NPK mineral fertilizers, increased protein levels with the increasing rate of NPK mineral fertilizers. Additionally, the interaction of NPK nano-fertilizers with organic manure increased proline content in seeds with the increasing rate of different mineral fertilizers. Overall, the application of NPK nano-fertilizers was found to improve soil fertility and increase crop productivity.

Mapping Crop Water Productivity of Rice Across Diverse Irrigation and Fertilizer Rates Using Field Experiment and UAV-based Multispectral Data

Mapping Crop Water Productivity of Rice Across Diverse Irrigation and Fertilizer Rates Using Field Experiment and UAV-based Multispectral Data

Integrating plant growth microorganisms in potato farming reduce soil CO2 emissions and improve crop quality

AbstractCurrent horticultural practices typically require high demands of fertilizers, leading to significant environmental impacts and increased production costs. Alternatives based on microbial inoculants have garnered considerable interest owing to their potential to enhance soil quality whilst reducing external inputs and costs, all without compromising productivity. This study aimed to compare the impact of four fertilizer application strategies, including mineral fertilizers and microbial inoculants, on crop yield, soil fertility and functionality and soil greenhouse gas emissions in potato production in Southern Spain. Four treatments were tested: (i) mineral fertilizers added to meet the crop's nutritional needs (F100); (ii) a 50% reduction of the F100 rate (F50); (iii) a 50% reduction of the F100 rate combined with the application of a formulation containing nutrient‐solubilizing bacteria, nitrogen‐fixing bacteria and non‐mycorrhizal fungi (BAI+FU) and (iv) a 50% reduction of the F100 rate combined with a formulation of N, P and K solubilizing bacteria (BAII). Results showed that crop yield was unaffected by the different fertilizer application treatments. However, the mean tuber weight and firmness were significantly higher under the BAI+FU treatment, indicating improved product quality. CO2 release rates decreased by 25%, 34% and 42% with F50, BAI+FU and BAII treatments, respectively, compared with F100. The N2O and CH4 emissions or soil nutrient contents were not affected by treatments, except for ammonium content, which was highest under the BAI+FU treatment. Additionally, whilst overall soil bacterial and fungal abundance was not significantly affected, the BAI+FU treatment resulted in a higher number of nirK (denitrification) and cbbL (carbon fixation) gene copies. Therefore, combining biofertilizers with reduced chemical fertilizer rates could represent a sustainable strategy for mitigating climate change whilst enhancing crop quality in potato production.

Evaluate the integrative effects of irrigation water level, furrow irrigation methods, and nitrogen fertilizer rate on tomato yield in semi-arid southern Ethiopia.

This study investigates the integrative effects of irrigation water management allowable depletion (MAD), furrow irrigation methods (FIM), and nitrogen fertilizer application rate (NFAR) on tomato yield components. These yield components include marketable, unmarketable, and total yield. Additionally, the study examines crop agronomy components such as plant height, number of branches, and root depth in semi-arid Southern Ethiopia. The research employs a factorial and split-plot design. Three types of FIM are assigned as the main plot, while three levels of irrigation water (50%, 75%, and 100% MAD) and four levels of NFAR (0%, 50%, 100%, and 150% NFAR) serve as the subplots, with three replications. The study results reveal significant impacts of these factors. All p-values for tomato yield and agronomy-measured components are less than 0.05. FIM, irrigation water level, and NFAR interaction affect marketable, unmarketable, and total tomato yield. The results ranged from 2.3 tons ha⁻1-43.9 tons ha⁻1 for marketable yield, 0.8 tons ha⁻1-8 tons ha⁻1 for unmarketable yield, and 6.3 tons ha⁻1-45.2 tons ha⁻1 for total yield. The integration of 75% MAD with 100% NFAR under conventional furrow irrigation, and 100% MAD with 100% NFAR under alternative furrow irrigation, was most preferable. This approach resulted in no loss of nitrogen fertilizer and saved 25% of irrigation water without reducing tomato yield. However, the interaction of deficit nitrogen fertilizer rate application, with or without full application of MAD and conventional or other furrow irrigation methods, caused the total yield to decrease. CFIM and AFIM with 100% MAD and 100NFAR treatments yielded the highest profits, while the FFIM approach under 50%MAD and 0%NFAR conditions negatively impacted profitability. Therefore, by adopting the preferable practices, farmers can achieve higher productivity and sustainability in tomato cultivation. This approach addresses the challenges posed by water scarcity and nutrient limitations.

Interactive Effects of Location and N- Fertilizer Rates on Grain Quality Traits of Bread Wheat Varieties at Arsi Zone, South-Eastern Ethiopia

Nowadays it is not only the amount of yield that is important, but also the quality of the grain produced, because the quality of the grain determines the direction of use. In view of this, the current work was conducted in 2017/2018 cropping season with factorial combinations of two bread wheat varieties (Lemu and Wane), five N-rates (0, 46, 92,138 and 184 kg N ha&amp;lt;sup&amp;gt;-1&amp;lt;/sup&amp;gt;) and two different locations (Lemu-Bilbilo and Tiyo). The experiment was laid down using a RCBD with three replications. The results explained that, with the exception of 1000 grain weight (TGW) and hectoliter weight (HLW), the remaining parameters included in this study are significantly influenced by the interactions of location x N-rate x variety, while the two-way interactions of location x variety and N-rate x variety were affected all studied parameters except HLW which didn’t affected by the interaction effects of location x variety. The maximum grain yield (7721 and 7481 kg ha&amp;lt;sup&amp;gt;-1&amp;lt;/sup&amp;gt;) was achieved from Wane and Lemu at Lemu-Bilbilo and Tiyo at N-rates of 184 and 92 kg ha&amp;lt;sup&amp;gt;-1&amp;lt;/sup&amp;gt;, respectively. The peak value of gluten index (GI) (87.9 and 87.4%) was determined in Wane and Lemu varieties, respectively, in unfertilized plot and at N rate of 138 kg ha&amp;lt;sup&amp;gt;-1&amp;lt;/sup&amp;gt;, sequentially and at par with 138 and 184 kg ha&amp;lt;sup&amp;gt;-1&amp;lt;/sup&amp;gt; for wane and at par with N rate of 46 kg ha&amp;lt;sup&amp;gt;-1&amp;lt;/sup&amp;gt; plus with unfertilized plot for Lemu variety in Lemu-Bilbilo. The value of GI recorded at unfertilized plots and N-rate of 46 kg ha&amp;lt;sup&amp;gt;-1&amp;lt;/sup&amp;gt; was significantly at par for Lemu variety, while for wane significantly the same as the GI obtained at N-rate of 46 and 92 kg ha&amp;lt;sup&amp;gt;-1&amp;lt;/sup&amp;gt; at Tiyo. The effects of N rates at Lemu-Bilbilo was significantly on the same level, but the peak value of wet gluten (55.1%) and dry gluten (20.7%) were gained at 184 kg N ha&amp;lt;sup&amp;gt;-1&amp;lt;/sup&amp;gt; in Tiyo and significantly the level of 46, 92 &amp; 138 kg N ha&amp;lt;sup&amp;gt;-1&amp;lt;/sup&amp;gt; for dry gluten and 138 kg N ha&amp;lt;sup&amp;gt;-1&amp;lt;/sup&amp;gt; for wet gluten. In Lemu-Bilbilo the HLW was increased with an increased N-rate, while in Tiyo it had increased to 92 kg N ha&amp;lt;sup&amp;gt;-1&amp;lt;/sup&amp;gt;. Based on parameters examined, the N rates of 92 and 138 kg ha&amp;lt;sup&amp;gt;-1&amp;lt;/sup&amp;gt; for both varieties at the Tiyo and Lemu-Bilbilo study sites were therefore economically justifiable.