Agrosystems, Geosciences & Environment最新文献

Studying the combining ability of pro-vitamin A enriched yellow maize inbred lines (Zea mays L.) provides valuable information on the breeding potential of these lines for developing high-yielding and biofortified maize hybrids with desirable agronomic traits. Twelve pro-vitamin A-enriched yellow maize inbred lines were crossed using a half diallel mating design with the objective of identifying the best combiners to use as testers and selecting the highest-performing hybrids for grain yield with desirable traits. Sixty-eight F₁ hybrids along with checks were evaluated across three environments at mid-altitude agroecology of Ethiopia during the 2022 main cropping season. Combined analysis of variance revealed significant differences (p ≤ 0.01) due to hybrids, environments, and hybrid × environment interactions for grain yield and agronomic traits, indicating that genotypes performed differently across environments. Eight hybrids were selected based on superior mean yield performance (6.92–7.95 t ha⁻¹), providing yield advantages of 15.6%–32.7% over the best check, warranting promotion to the next stage of hybrid evaluation. Analysis of variance for general combining ability (GCA) and specific combining ability showed significant differences (p ≤ 0.001) for all traits studied, indicating that these traits are controlled by both additive and non-additive gene effects. Inbred lines L2, L6, L8, L10, and L12 exhibited high, positive, significant GCA effects on yield and other traits. Inbred lines L10 and L12 showed the best combiners for most traits and exhibited high GCA effect for yield. Their crosses generated the top yield performance and negative contributions to foliar diseases. Thus, these inbred lines can be used as testers for future provitamin A maize breeding program in the mid-altitude agroecology of Ethiopia.

Sesame (Sesamum indicum L.) is an important oil crop in the world. A significant genotype by environmental interaction (GEI) presents challenges in the selection of superior genotypes. The study was initiated to identify stable and high-yielding sesame genotypes. Accordingly, 16 sesame genotypes were evaluated in a randomized complete block design at six distinct environments. All-important data were collected and analyzed using Statistical Analysis Software (SAS). Most of the analyzed traits showed highly significant differences for genotypes, location, and genotype by environment (GE) interaction, which indicated the presence of genetic variability among tested genotypes across environments. Stability analysis was estimated by the additive main effects and multiplicative interaction (AMMI) model and genotype and genotype by environment (GGE) biplots. AMMI analysis of variance revealed highly significant (p < 0.01) variations among environments, genotypes, GE interaction, and four interaction principal component analyses (IPCAs). The first four IPCAs (IPCA1, IPCA2, IPCA3, and IPCA4) showed high significance and contributed 56.3%, 23.9%, 11.3%, and 2.3% of the total GE interaction, respectively. Genotypes G15 and G4 had higher with close to concentric circles indicating the wide adaptability over the tested environments and similar agroecology. In addition, the genotypes showed microbial blight resistance in western parts of Ethiopia and hence were selected as potential candidates for possible release in the study area.

Morphometric analysis is crucial for watershed management, especially for estimating infiltration rate and erosion characteristics. However, there is limited research on the relationship between morphometric characteristics and soil hydrological properties in the Kiltie watershed. The study is aimed at exploring the relationship between morphometric characteristics and soil hydrological properties in the Kiltie watershed. The study utilized the Shuttle Radar Topography Mission digital elevation model (30 × 30 m spatial resolution) and ArcGIS 10.7.1 software to extract and analyze morphometric parameters. A numerical scheme was used to evaluate soil hydrological properties in relation to morphometric parameters. The morphometric analysis reveals that drainage pattern was dendritic and the maximum stream order of the watershed was five. Total number of stream of all orders was 560, with a total length of 358.277 km. Out of all order, 53.04% were covered by the first order, 23.03% by the second order, 10% by third order, 9.29% by fourth order, and 4.64% by fifth order. The watershed's higher drainage density (19.21 km/m2) and ruggedness number (3.55) indicate higher erosion sensitivity and lower surface permeability and infiltration, indicating a more resilient ecosystem. The values obtained through morphometric analysis and numerical scheme classification showed the watershed had low surface soil permeability, low infiltration rate, and high runoff, with a total weight score below six. This study and scheme could be useful for planners and decision-makers as a baseline in implementing successful soil and water conservation strategies. For future studies, we recommended that the extent of the vulnerability to erosion-prone areas should be identified through multi-criteria decision-making methodologies.

A participatory field experiment was conducted during the 2024 main cropping season in collaboration with local farmers who jointly managed and evaluated the trials. The experiment aims to evaluate the effects of biochar-based fertilizer (BBF) on soil properties and bread wheat (Triticum aestivum) productivity grown on acidic Nitisols. Three fertilizer treatments (sole BBF, BBF plus 50% recommended nitrogen (N) rate (46 kg N ha⁻¹), and 100% recommended N rate (92 kg N ha⁻¹) were arranged in a randomized complete block across 18 farmers’ fields, each representing a replication site. Based on the initial soil pH results, the experimental fields were classified into three acidity levels (strong, moderate, and slight). Postharvest analysis results revealed that BBF combined with 50% recommended N fertilizer improved soil pH, organic carbon, and total nitrogen contents, compared to 100% recommended N fertilizer. Furthermore, the combined application of BBF with 50% recommended N fertilizer consistently yielded the highest wheat grain production across all acidity levels. On average, the combined treatment surpassed 100% recommended N fertilizer by 49%, 25.9%, and 17.5% in strong, moderate, and slightly acidic conditions, respectively. The effects of BBF application, either alone or in combination with 50% recommended N fertilizer, on soil properties, wheat yield, and yield components were more pronounced in strongly acidic soil, followed by moderate and slightly acidic conditions. Overall, integrating BBF with 50% recommended N fertilizer improved soil fertility and wheat productivity, suggesting a sustainable soil management option for acidic soils; however, further multi-season validation is recommended to confirm these findings.

Acidic soils in Ethiopia's Hadiya Zone limit crop production through aluminum toxicity and phosphorus (P) fixation, which constrain camelina potential. Though drought tolerant, camelina needs sufficient P. Triple superphosphate (TSP) often becomes ineffective because P is rapidly fixed; coffee husk biochar may reduce fixation and improve P availability. Field experiments examined combinations of amendments to test practical options for smallholder farmers in Hadiya, Ethiopia. This study evaluated camelina growth, yield, and P use efficiency under coffee husk biochar and TSP in Hadiya. A split-split-plot design with three replications tested two cultivars (Zeytee-1 and Syria), four TSP rates (0, 23, 46, and 69 kg ha⁻¹), and four biochar rates (0, 10, 12, and 14 t ha⁻¹). Biochar significantly enhanced growth: 14 t ha⁻¹ increased leaf area by 48% and plant height by 39%, improving vigor. Combined biochar and TSP maximized yield components; Syria doubled siliques per plant with 69 kg ha⁻¹ TSP plus biochar. Peak grain yields reached 2.64 t ha⁻¹ for Syria (46 kg ha⁻¹ TSP + 12 t ha⁻¹ biochar) and 2.60 t ha⁻¹ for Zeytee-1 (69 kg ha⁻¹ TSP + 14 t ha⁻¹ biochar). Biochar raised phosphorus recovery efficiency to 10.8% when combined with 23 kg ha⁻¹ TSP. Cultivar responses differed: Zeytee-1 favored higher inputs; Syria performed best with balanced fertilization. Applying 12–14 t ha⁻¹ coffee husk biochar with TSP (Zeytee-1: 46–69; Syria: 23–46 kg ha⁻¹) enhances phosphorus efficiency. This practice improves marginal soil productivity and supports camelina as a viable oilseed for acidic soils.

Alternative fertilizer-phosphorus (P) sources created by recycling excess nutrients from waste sources, such as struvite (MgNH₄PO₄·6H₂O), require further research to determine their niche in agriculture and potential environmental implications. The objective of this study was to evaluate rice (Oryza sativa) response and greenhouse gas emissions intensity from a real-wastewater-derived and synthetic electrochemically precipitated struvite (ECST_Real and ECST_Syn, respectively) and a chemically precipitated struvite compared to monoammonium phosphate (MAP) and an unamended control grown under flood- and furrow-irrigated conditions in a P-deficient, silt-loam soil in the greenhouse. A pure-line rice variety was grown under delayed-flood irrigation for ∼155 days in 2022, and a hybrid rice variety was grown for ∼170 days under simulated furrow-irrigation in 2023. In both 2022 and 2023, aboveground dry matter did not differ among P-fertilized rice treatments. Total plant P uptake in 2022 from MAP was 34.2 kg ha⁻¹, which was similar to all struvite fertilizer-P sources. In 2023, aboveground P uptake from ECST_Real was numerically greatest at 19.8 kg ha⁻¹ and similar to ECST_Syn and MAP at 18.6 and 17.9 kg ha⁻¹, respectively. The ECST_Real and ECST_Syn sources were similar among fertilizer-P sources for all measured or calculated rice properties, except for methane emissions intensity in 2022 and aboveground tissue-N concentration and uptake, total aboveground N uptake, and total plant P uptake in 2023. Results emphasized that the use of struvite could provide a viable fertilizer-P source for both flood- and furrow-irrigated rice production systems.

Aloe vera (Aloe vera L.) has been utilized for various therapeutic and cosmetic purposes; however, its agronomic management in Bangladesh remains underexplored. Therefore, a field trial was performed in Mymensingh, Bangladesh, to evaluate the combined effects of organic and inorganic fertilizers (IFs) on growth, nutrient composition, medicinal components, and post-harvest soil fertility of A. vera. Nine treatments consisting of organic matter (OM) (cow dung [CD] and poultry manure [PM]) and IFs, namely, IF₀OM₀, IF₁₀₀OM₀, IF₈₅OM₁₅, IF₇₀OM₃₀, IF₅₅OM₄₅, IF₄₀OM₆₀, IF₂₅OM₇₅, IF₁₀OM₉₀, and IF₀OM₁₀₀, were laid out in a Randomized Complete Block Design with three replicates. The results of the study confirmed that integrated nutrient management substantially enhanced plant performance with the IF₂₅OM₇₅ treatment in both CD and PM combinations, including the tallest plants, the highest leaf number, the largest leaf area, and the most suckers. Interestingly, CD containing integrated fertilizer produced about 14% more leaf biomass than PM containing integrated fertilizer, while PM-containing treatments increased nutrient (N, P, K, Fe, Zn, and Mn) acquisition more effectively than CD-based fertilizer. Biochemical assessments revealed that protein content peaked under IF₁₀₀OM₀. In contrast, chlorophyll, aloin, flavonoids, and phenolics were significantly higher in OM-dominant treatments than IF, especially IF₀OM₁₀₀ in both CD and PM containing fertilizer, which produced the highest aloin (494 µg g⁻¹) and phenolics (29.35 mg gallic acid equivalents g⁻¹ fresh weight content. The post-harvest soil analysis revealed that higher OM, particularly PM, significantly enhanced soil fertility by increasing organic matter, N, P, S, Zn, and exchangeable K, Ca, and Mg compared with CD containing integrated fertilizer. Overall, the study suggested that integrating OM with moderate IF, especially IF₂₅OM₇₅ for both CD and PM_, can improve growth, nutritional value, medicinal properties, and soil fertility of A. vera.

Productive forage with sufficient nutritive value is essential to profitable grazing operations. Application of nitrogen (N) fertilizer directly impacts pasture growth, but N rates must be carefully calibrated to minimize production costs and losses to the environment. We evaluated forage accumulation response, nitrogen use efficiency (NUE), and % ¹⁵N recovery of meadow fescue [Schedonorus pratensis (Huds.) P. Beauv.], orchardgrass (Dactylis glomerata L.), and endophyte-free tall fescue [Schedonorus phoenix (Scop.) Holub] in response to N rate in a controlled greenhouse environment using two soil types. Nitrogen was split-applied at cumulative annual rates of 0, 67, 135, 202, 269, and 336 kg N/ha. The first N application was ¹⁵N-enriched 5% atom ammonium nitrate (NH₄NO₃) solution, while the three subsequent N applications were made following harvest events with reagent-grade NH₄NO₃. Nitrogen recovery from the first application was estimated from the atom % ¹⁵N in the dry matter (DM) sample from each harvest event. For all species, DM forage accumulation increased with N rate up to 202 kg N/ha, and orchardgrass had the greatest DM accumulation at all N rates. NUE in all species declined with increased N. % ¹⁵N recovery of the first fertilizer application was significantly different across species and N rates, ranging from 35% to 70%. In pasture systems with these species in warm summer continental climates, N fertilizer timing and application strategy should be calibrated with weather, pasture conditions, and livestock demand.

Improving nitrogen (N) use efficiency in Brassica carinata is essential to sustain yield and lower biofuel carbon intensity under variable field conditions. We hypothesized that integrating physiological indicators, such as the nitrogen nutrition index (NNI) and the critical nitrogen uptake curve (CriNUC), into N management frameworks would better discriminate crop N status and improve the diagnostic evaluation of fertilizer performance in B. carinata under temperate field conditions. A 2-year, multi-site field experiment in Uruguay evaluated conventional split urea (CONTROL), slow-release, and nitrification-inhibited fertilizers (ENTEC 150 and Sulfammo-NPRO) at 0, 90, and 150 kg N ha⁻¹. Crop responses were assessed through yield components, nitrogen uptake, nitrogen use efficiency (NUE) metrics (agronomic efficiency of nitrogen [AE_N], recovery efficiency of nitrogen [RE_N], and IE_N), and physiological indicators (NNI and CriNUC). ENTEC 150 increased grain yield by 70% relative to the CONTROL and consistently maintained N sufficiency from elongation to flowering. Across treatments, NNI and CriNUC provided complementary, in-season insights that were not captured by static NUE indices, particularly under environmental stress. Neither RE_N nor AE_N correlated with NNI at flowering, highlighting potential physiological or structural constraints (e.g., lodging) that limit predictability under field conditions. Treatments with NNI > 1 showed increased protein and reduced oil concentration, confirming trade-offs between productivity and grain composition. While results are exploratory due to the use of a generic dilution curve, our findings suggest that combining enhanced-efficiency fertilizers with crop-based diagnostics supports more precise and adaptive nitrogen management in B. carinata. Further calibration is needed to refine these tools and validate their utility for decision-making across diverse environments.

Garlic (Allium sativum), a vegetable crop used for food, medicine, and condiments, is affected by white rot (Sclerotium cepivorum). Garlic yield reduction is influenced by several factors, with biotic stresses, particularly fungal pathogens, being among the most significant. The main aim of this work was to examine the effect of bacterial antagonists in preventing or controlling the attack of white rot. Bacterial antagonists and the phytopathogens were isolated and characterized using the serial dilution technique and standard microbiological procedures. The biocontrol properties of bacterial isolates, including fungal inhibition, production of hydrolytic enzymes, and bioactive compounds, were determined. Similarly, the in vivo inhibition potential of 10 selected antagonists was evaluated under greenhouse conditions. Eleven isolates, accounting for 47.8%, inhibited the radial growth of white rot at disease incidences of 1%–4% and 33.3%, respectively. Among the bacterial isolates, 10 (90.9%) showed cellulase activity, while 6 (54.6%) and 5 (45.5%) were positive for chitinase and protease production, respectively. Furthermore, 11 (100%) and 5 (45.5%) of the isolates were positive for ammonia and hydrogen cyanide production, respectively. Garlic plants treated with bacteria produced 135.0%–142.2%, and 291.7%–370.8% greater height and weight, respectively. The isolates exhibited 99% sequence homology with Pantoea species, including Pantoea agglomerans, as well as Enterobacter species, Enterococcus species, and E. gallinarum. The budget was one limitation to further evaluating the effect of bacterial antagonists against white rot affecting garlic under field conditions. This finding indicated that the application of potential microbial inoculants can control plant disease. Consequently, isolates WUGRB-14 and -92 (where WUGRB is Wollo University Grasspea Rhizobacteria) can be recommended for field application as an alternative to chemical pesticides.