Field Experiment Research Articles

How do farming practices influence the richness and floristic composition of weeds in some Mexican maize fields?

The milpa is a historically successful Mesoamerican agroecosystem, consisting of a mixture of cultivated plants with associated vegetation that is partially managed. Conventional farming practices, like weeding and fertilization, have modified some ecological parameters of weeds, affecting their ecological, evolutionary, cultural, and productive roles. This study explores these changes from various perspectives: field experiments in fields with different management histories, contrasting treatments within these fields, farmer interviews and field walks, in San Bartolo del Llano, Ixtlahuaca, Mexico. A field experiment in milpas with different histories of farming practices (traditional vs conventional) was conducted to understand (a) the effect of the history of farming practices on richness, composition, and biomass of aboveground weed vegetation and the seed bank, (b) the effect of contrasting weeding treatments within these fields on the biomass of weeds and maize, and (c) farmers’ traditional knowledge and use of these plants. Farming practices did not affect species richness (43 species) of the aboveground weed vegetation, but a history of herbicide use increased monocot biomass and reduced useful weeds. More introduced monocots were recorded in conventionally managed fields; manual weeding led to more species, including more monocots and dicots, a higher biomass of weeds, and more native and exotic species. The composition differed between plots with different farming practices and treatments. The seed bank contained more species (54) than the aboveground vegetation. Maize ears’ and total biomass were somewhat higher in conventionally treated fields, but no differences were found between treatments. We found a considerable species turnover, with some species disappearing or becoming rare, particularly useful ones, and others being introduced‚ particularly grasses. Traditional management can help farmers keep useful weeds and higher biodiversity, thus contributing to overall productivity. Though herbicides reduce labor requirements, improved management should combine the benefits of traditional farming with some modernization.

马铃薯挖掘机仿真与试验

In this study, the potato excavator with loosening shovel was designed in order to solve the problems of serious soil obstruction and high excavation resistance during the potato harvest. Using EDEM discrete element simulation software, potato excavation simulation experiments were carried out on soil broken effects and excavation resistance. Through the comparative analysis with loosening shovel and without, the results showed that the increase of soil broken effects was close to 52%, and the excavation resistance decreased by 16.57%. Through the two-factor and three-level field orthogonal experiment with excavation depth and loosening depth as influencing factors, the optimal operating parameters was determined for potato excavators: the excavation depth was 23 cm and the loosening depth was 20 cm. At this time, the excavation potato rate was 98.21%, and the rate of damaged potato was 1.31%. The traction resistance was 1826 N, which met the requirements of relevant industry standards. Through comparative analysis of simulation experiments and field experiment, it was found that when the excavation depth was 23 cm and the loosening depth was 20 cm, the error value of traction resistance was 11.3% between simulation experiments and field experiments. The discrete element simulation analysis can provide a preliminary reference for potato excavation design.

Efficiency of phosphorus fertilizers: research results in long-term field experiments in Russia, Great Britain and China

The results of research in long-term field experiments on the effectiveness of phosphorus fertilizers are presented. All experiments were based on the classical scheme and included, in addition to the control variant (without fertilizers), a nitrogen-potassium background, on which the effectiveness of phosphorus fertilizers was studied. At the same time, regional specifics were taken into account in each experiment: liming at the Experimental Station of the All-Russian Research Institute of Agrochemistry (Russia), the effectiveness of phosphorus fertilizers at increasing doses of nitrogen N100–300 at the Rothamsted Experimental Station (Great Britain), a combination of phosphorus fertilizers with manure at the Chinese National Soil Fertility Monitoring Base. In long-term experiments, the dynamics of changes in the content of mobile phosphorus, as well as individual fractions, taking into account the emerging balance of P2O5, are presented. It is shown that the redistribution of phosphorus between different soil fractions is reversible, and the direction of the processes depends on the emerging balance of P2O5. Phosphorus accumulated in more firmly held forms can subsequently be released and absorbed by cultivated crops. In all field experiments an increase in the yield gap between NK and NK + P variants was observed over time. On the one hand, this is due to a significant decrease in the phosphorus content in the background NK variant (in acidic soils – also an increase in Al mobility), in which phosphorus removal significantly exceeds control (without fertilizers), on the other – a significant increase in the content of P2O5 in the soil with a positive balance. In a long-term experiment at the Experimental Station of the Institute of Agrochemistry, the difference coefficient of phosphorus utilization from fertilizers was 25–27, at the Rothamsted station – 25–41, at the Chinese National Soil Fertility Monitoring Base – 45%. Attention is drawn to the high payback of phosphorus fertilizers in experiments at the Rothamsted experimental station (Great Britain) – 22–39 kg of grain/kg of P2O5 (when cultivating winter wheat in crop rotation). The main method of increasing payback in this case was the use of high doses of nitrogen – up to 200 kg N/ha. Studies have shown that liming acidic soils to a slightly acidic reaction, the use of zinc micronutrients, as well as phosphate-mobilizing microorganisms, are essential methods to increase the effectiveness of phosphorus fertilizers.

Residual Effect of Organics and Humic Acid on Physical, Chemical and Biological Property of Soil after Harvest of Succeeding Chickpea

A field experiment was conducted at Agronomy Instructional Farm, Department of Agronomy, C. P. College of Agriculture, SDAU, Sardarkrushinagar to study the effect of organics and humic acid on kharif pearlmillet and their residual effect on succeeding chickpea during kharif- 2022 to 2023 and rabi 2022-23 to 2023-24. The soil of the experimental plot was loamy sand in texture, alkaline in reaction, normal in salinity, low in organic carbon, available N, medium in available P2O5 and K2O and low DTPA- extractable Fe, Mn, Zn and Cu. The treatments were applied in kharif pearlmillet crop and their residual effect was studied in succeeding chickpea crop. Residual effect of FYM @ 10 t ha-1 recorded significantly increased OC (0.298, 0.302 and 0.300 per cent), available N (177.28, 180.10 and 178.69 kg ha-1), P2O5 (41.20, 42.04 and41.62 kg ha-1) was observed during both the year and pooled result and total bacterial count (156.26 cfu g soil-1) in pooled result soil with the application of FYM @ 10 t ha-1. While application of humic acid did not get significant result and but numerically increased above mention parameter under the soil application of humic acid 30 kg ha-1.

Synergistic Effect of Iron and Zinc Nanoparticles with Recommended Nitrogen Dose on Production and Grain Quality of Maize (Zea mays L.) Cultivars Under Drought Stress

Abiotic factors, such as drought, can significantly impact the vegetative growth and productivity of maize. To investigate the effects of the combined foliar application of zinc (Zn) and iron (Fe) nanoparticles with the recommended nitrogen dose (RND) on maize production and grain chemical composition under different water regimes, two field experiments were conducted in El-Ayyat city, Giza, Egypt, during the summer seasons of 2022 and 2023. This study utilized a split-split-plot experimental design with three replications. The main plots were designated to different water regimes (100, 80, 60, and 40% of estimated evapotranspiration), while the sub-plots were randomly distributed with Zn and Fe nanoparticle concentrations (0, 100, and 200 mg/L). The sub-sub-plots were randomly allocated to three maize cultivars (SC-P3062, SC-32D99, and SC-P3433). The results revealed that exposure to drought conditions resulted in a significant decline in the yield and yield-related attributes across all maize cultivars examined. Grain yield decreased by 10–50% under drought conditions. However, the foliar application of Zn and Fe nanoparticles was found to significantly improve grain yield, protein content, oil content, starch content, crude fiber, ash, and macro- and micronutrient concentrations in the maize cultivars under control and drought stress conditions. The foliar application of Zn and Fe nanoparticles at a concentration of 200 mg/L to the SC-P3433 maize cultivar led to the greatest grain yield per hectare, reaching 11,749 and 11,657 kg under the irrigation regimes with 100 and 80% total evapotranspiration, respectively. According to the assessment using the relative drought index, the SC-P3062 maize cultivar demonstrated tolerance (T) to water stress conditions. In conclusion, the foliar application of Zn and Fe nanoparticles (100–200 mg/L) effectively mitigated the negative effects of drought stress on maize plants. This approach can be recommended for farmers in arid and semi-arid regions to maintain and improve maize yield and grain quality under water-deficit conditions.

Using microbes to suppress overwintering inoculum of Monilinia laxa on mummified fruits and to protect cherry blossoms and fruit from infection

Cherry brown rot, primarily caused by Monilinia laxa, poses a significant threat to cherry production in the UK. Traditional control methods are labour-intensive or environmentally damaging, favouring alternative solutions such as using biological control agents (BCAs). This study investigated the survival and efficacy of two BCAs, Bacillus subtilis (B91) and Aureobasidium pullulans (Y126), in reducing M. laxa populations on mummified fruits and cherry blossoms. Field experiments were conducted to assess the survival of B91 and Y126 on mummified fruits over winter and their effect on M. laxa sporulation in spring. Additionally, the efficacy of the two BCAs when applied to cherry blossoms was evaluated, at different times of application relative to M. laxa inoculation. Y126 could persist on blossoms and throughout the growing season. B91 population level declined rapidly on blossoms but recovered once fruits appeared. Neither BCA usefully reduced the concentration of M. laxa. Y126 was marginally more effective at long-term reduction. On mummified fruits, Y126 population size declined rapidly within the first two weeks after inoculation before stabilising. B91 survived slightly longer. Longer interaction times between M. laxa and the BCAs in the late winter resulted in lower spore counts of M. laxa from mummified fruits. While both BCAs reduced M. laxa populations when applied close to M. laxa inoculation, BCA populations were not maintained at effective levels throughout the growing season. These results suggest that multiple applications targeting critical periods (blossom and pre-harvest) are necessary for effective control of M. laxa by either of these BCAs.

Framing of Differences: Visual Product Frames Reduce Consumer Choice Deferrals

Consumer choice deferral contributes to the low conversion rate in online retailing. This article investigates the impact of visual product frames on consumers’ decisions regarding choice deferral. The authors show that using visual frames to separate options in a product assortment increases consumers’ relative use of the by-alternative (vs. by-attribute) approach for option comparisons, which induces greater perception of assortment variety and subsequently decreases choice-deferral rate. Through seven preregistered studies (including an eye-tracking study and a field experiment), the authors obtain convergent empirical evidence for these proposed effects and suggest actionable guidelines for online retailers regarding how to best design their product displays to encourage sales.

Impact of foliar application of phyllosphere yeast strains combined with soil fertilizer application on rice growth and yield

BackgroundThe application of beneficial microbes in agriculture is gaining increasing attention as a means to reduce reliance on chemical fertilizers. This approach can potentially mitigate negative impacts on soil, animal, and human health, as well as decrease climate-changing factors. Among these microbes, yeast has been the least explored, particularly within the phyllosphere compartment. This study addresses this knowledge gap by investigating the potential of phyllosphere yeast to improve rice yield while reducing fertilizer dosage.ResultsFrom fifty-two rice yeast phyllosphere isolates, we identified three yeast strains—Rhodotorula paludigena Y1, Pseudozyma sp. Y71, and Cryptococcus sp. Y72—that could thrive at 36 °C and possessed significant multifarious plant growth-promoting traits, enhancing rice root and shoot length upon seed inoculation. These three strains demonstrated favorable compatibility, leading to the creation of a yeast consortium. We assessed the combined effect of foliar application of this yeast consortium and individual strains with two distinct recommended doses of chemical fertilizers (RDCFs) (75 and 100%), as well as RDCFs alone (75 and 100%), in rice maintained in pot-culture and field experiments. The pot-culture experiment investigated the leaf microbial community, plant biochemicals, root and shoot length during the stem elongation, flowering, and dough phases, and yield-related parameters at harvest. The field experiment determined the actual yield. Integrated results from both experiments revealed that the yeast consortium with 75% RDCFs was more effective than the yeast consortium with 100% RDCFs, single strain applications with RDCFs (75 and 100%), and RDCFs alone (75 and 100%). Additionally, this treatment improved leaf metabolite levels compared to control rice plants.ConclusionsOverall, a 25% reduction in soil chemical fertilizers combined with yeast consortium foliar application improved rice growth, biochemicals, and yield. This study also advances the field of phyllosphere yeast research in agriculture.

A frameshift mutation in JAZ10 resolves the growth versus defense dilemma in rice

CRISPR-Cas9 genome editing systems have revolutionized plant gene functional studies by enabling the targeted introduction of insertion-deletions (INDELs) via the nonhomologous end-joining (NHEJ) pathway. Frameshift-inducing INDELs can introduce a premature termination codon and, in other instances, can lead to the appearance of new proteins. Here, we found that mutations in the rice jasmonate (JA) signaling gene OsJAZ10 by CRISPR-Cas9-based genome editing did not affect canonical JA signaling. However, a type of mutant with an INDEL that yielded a novel frameshift protein named FJ10 (Frameshift mutation of JAZ10), exhibited enhanced rice growth and increased resistance to brown planthopper attacks. Overexpression of FJ10 in wild-type plants phenocopies OsJAZ10 frameshift mutants. Further characterization revealed that FJ10 interacts with Slender Rice 1 (OsSLR1) and F-box/Kelch 16 (OsFBK16). These interactions disrupt the function of OsSLR1 in suppressing gibberellin-mediated growth and the function of OsFBK16 in repressing lignin-mediated defense responses, respectively. Field experiments with FJ10-expressing plants demonstrate that this protein uncouples the growth-defense tradeoff, opening broad avenues to obtain cultivars with enhanced yield without compromised defenses.

Legacy effects of crop diversity on weed-crop competition in maize production

The legacy effects of crop diversity on maize (Zea mays L.) tissue nutrient composition, weed community structure, and intensity of weed-crop competition were assessed through a field experiment at two sites in the northeastern United States. Fields were conditioned with crop diversity gradients from summer 2016 to spring 2019. The crop diversity gradients ranged from a single cultivar to sixteen intercropped cultivars (four species, four cultivars per species) and were established in organic annual and perennial cropping systems. Following the three-year conditioning phase, maize was planted across the entire experiment, and each conditioning-phase diversity treatment was split into weed-free, ambient-weed, moderate-weed, and heavy-weed treatments. Within each cropping system, the effect of crop diversity legacy on weed-crop competition was negligible. In contrast, weed-crop competition varied between the maize grown in soil conditioned by the annual and perennial cropping systems.

Chemical Topping and Planting Density Interactively Affect Cotton Growth and Partitioning Index

Due to the labor shortage, replacing manual topping with chemical topping has become an important practice in cotton-producing areas such as Xinjiang, China. Similarly, increasing planting density is a common strategy to enhance cotton yields. This study aimed to quantify the interactive effects of chemical topping and planting density on cotton growth and assimilate partitioning. To achieve this, a two-year (2020–2021) field experiment was conducted in Xinjiang, China. The main plots were assigned low (15 plants m−2) or high plant density (25 plants m−2), and the subplots were chemical topping using heavy amounts of mepiquat chloride (MC) or manual topping. The dynamics of dry matter accumulation and partitioning in cotton were well quantified using a beta-growth function with an overall nRMSE of 11.5%. Results indicated that chemical topping increased aboveground dry matter maximum by 4.88%, fruit dry matter maximum by 17.9% and seed cotton yield by 14.0% compared to manual topping. At low plant density, the partitioning index between vegetative and reproductive organs showed no significant differences. However, at high plant density, the time when 50% of assimilate partitioning to reproductive organs for chemical topping was 2.6 physiological days (under optimal temperature conditions) delayed than that for manual topping, resulting in a 2.7 physiological days delay in the time that fruits reached maximum growth rate. The results of the study suggest that applying chemicals for topping a little earlier in high-density planting could reduce the negative effects of delayed boll growth and promote carbon assimilate partitioning to fruit growth.

Comparative Efficacy of Insecticides against Fall Armyworm (Spodoptera frugiperda) in Baby Corn

Aims: The fall armyworm (Spodoptera frugiperda) is a major pest threatening baby corn production, significantly impacting yield and profitability. This study aimed to evaluate the efficacy of various insecticides and their combinations in managing fall armyworm populations while ensuring sustainable crop production. Study Design: Randomized Block Design (RBD). Place and Duration of Study: Maize Research Centre, Agricultural Research Institute, Rajendranagar, Hyderabad, during the rabi season of 2022–2023. Methodology: Field experiments were conducted to assess the impact of seed treatments, foliar sprays, and their combinations on pest control, crop performance, and natural enemy conservation. The experiment followed a Randomized Block Design with three replications and eight treatments, T1 (tetraniliprole 480 FS and cyantraniliprole 10.26% OD spray, T2 (cyantraniliprole 19.8% + thiamethoxam 19.8% FS and spinetoram spray), T3 (cyantraniliprole 600 FS and chlorantraniliprole 9.3% + lambda-Cyhalothrin 4.6% ZC spray), T₄ (chlorantraniliprole 18.5% SC), T₅ (emamectin Benzoate 5% SG), T₆ (flubendiamide 480 SC), T₇ (dimethoate 30 EC) and T8 (untreated control). Insecticides were applied twice at a 14-day interval. Observations on leaf injury rating (LIR) and percent infestation were recorded using the standard 1–9 scale given by modified Davis and Williams. Pre-treatment observations were taken one day before spraying, and post-treatment observations were recorded at 7 and 14 days after each application. Parameters such as percent reduction over control, dehusked cob yield, green fodder yield, and cost-benefit ratio were calculated to evaluate treatment efficacy. Results: Results indicated that seed treatments followed by foliar sprays provided superior control of fall armyworm, with T2 (cyantraniliprole 19.8% + thiamethoxam 19.8% FS and spinetoram spray) demonstrating the lowest leaf injury ratings and highest yield benefits. T3 (cyantraniliprole 600 FS and chlorantraniliprole 9.3% + lambda cyhalothrin 4.6% ZC spray) exhibited comparable performance, followed by T1, T4, T5, T6 and T7. The study underscores the importance of integrating effective pest management strategies to enhance baby corn productivity and profitability. Conclusion: The study highlights the effectiveness of integrating seed treatments with foliar sprays for managing S. frugiperda in baby corn. T3 and T2 emerged as the most effective treatments, both in terms of pest control and economic viability, underscoring their potential for sustainable pest management and enhanced crop productivity.

We Are Not Equipped to Identify the First Signs of Cyber–Physical Attacks: Emotional Reactions to Cybersecurity Breaches on Domestic Internet of Things Devices

The increasing number of domestic Internet of Things (IoT) devices in our lives leads to numerous benefits, but also comes with an increased risk of cybersecurity breaches. These breaches have psychological consequences for the users. We examined the nature of the psychological impact of cybersecurity breaches on domestic IoT by investigating emotional experiences in a scenario study (Study 1) and a field experiment (Study 2) using the five emotion components of the Component Process Model (CPM) and emotion regulation as a framework. We replicated a three-dimensional structure for emotional experiences found in a previous study, with an addition of an ancillary fourth dimension in the second study. The first dimension represents emotional intensity. The second bipolar dimension describes constructive vs. unconstructive action tendencies. On the third dimension, also bipolar, cognitive and motivational emotion features are opposed to affective emotion features. The fourth dimension, labeled distress symptoms, mainly reflects negative emotions. In Study 2, most of the introduced frequent irregularities on IoT devices were not noticed, and the intensity of emotional reactions and tendencies to react in a constructive way decreased throughout the phases of the experiment. These findings reveal that we are not emotionally equipped to identify potential threats in the cyber world.

How does lime and rice straw compost application affect arsenic uptake in rice after a century of cropping under flooded conditions?

ABSTRACT Arsenic (As) uptake by rice is mainly controlled by the redox potential, amount of iron- and aluminum-bearing minerals and silicon (Si) availability in paddy soil. These soil properties are altered upon long-term continuous rice cultivation, and differences in soil properties arising from different agricultural management practices can influence As behavior in soils. This study aimed to clarify how long-term soil management with and without liming and rice straw compost application influences As uptake by rice. Soil and rice samples were collected from plots with continuous application of NPK mineral fertilizer with and without lime and from plots applied with NPK mineral fertilizer and lime with 750 and 2250 g m−2 straw compost in a long-term experimental paddy field established in 1926. Concentrations of As in rice shoots and panicles from the 92nd to 97th cropping seasons were determined. Hydrochloric acid (1 mol L−1 HCl)-extractable As and pseudototal As concentrations were also determined in select archived soil samples collected from the 52nd to 97th cropping seasons and for the 97th cropping season, respectively. Arsenic uptake by rice was lowest in the plots with lime and 2250 g m−2 rice straw compost application because application of excess organic amendments induced strong reducing conditions, which resulted in a loss of As and Fe minerals from the soil. In this plot, As uptake was lower in the year when no precipitation occurred over a longer period of days during the mid-summer drainage. Despite the increase in the uptake of Si with the application of rice straw compost, the ability of Si to mitigate As uptake was not apparent. The uptake of As by rice in the plot without liming was lower although this plot had a higher concentration of HCl-extractable As in the soil, possibly because As dissolution under flooded conditions was suppressed by the presence of low-crystalline Al minerals. In conclusion, As uptake in rice decreased with the long-term application of excess rice straw compost and in the absence of liming.

Nutrient Distribution in the Soil Profile Under Different Tillage Practices During a Long-Term Field Trial

Conservation tillage practices are increasingly used in agricultural systems. However, these practices require a complex approach regarding soil nutrition. Adequate nutrient content in soils is important for crop production, as reduced and no-tillage practices change the distribution of nutrient contents (P, K, Mg, and Ca) in the soil profile, necessitating new approaches for agronomists in crop nutrition. Little is known about the time changes in nutrient distribution in the soil profile under conservation tillage practices. Long-term field experiments with conventional (CT—plowing to 20–22 cm), reduced (RT—chiseling to 8–10 cm), and no-tillage (NT) practices were established in Prague–Ruzyně (Czech Republic) in 1995. This four-year crop rotation consisted of winter wheat changing with oilseed rape or pea. The soil nutrient contents have been determined since 2009 using the Mehlich 3 method and through extraction in 0.5 M ammonium acetate. The obtained results showed that P, K, and, to a lesser extent, Mg contents increased in the soil surface layer (0–10 cm) under the reduced and no-tillage practices, whereas Ca and pH values showed an opposite trend. We found an unbalanced ratio of nutrients in the upper soil layer in RT and NT caused by a high concentration of the monovalent cation K+ and the leaching of the divalent cations Ca2+ and Mg2+ into the deeper soil layers. In conventional practices, the ion contents are equalized throughout the topsoil due to the soil inverting during plowing. The determination of nutrient contents in deeper soil layers revealed that, over time, calcium, magnesium, and potassium were transported to deeper parts of the soil profile under RT and especially NT. Low nutrient ratios were found in the surface layer under RT and NT, negatively affecting the quality of the soil surface layer, including its structure. Fertilizer management and nutrient ratios in soils under RT and NT should be considered to maintain and possibly improve sustainable agricultural practices in fields with reduced or no-tillage practices. Furthermore, nutrient contents and their mutual ratios should be evaluated in more soil layers under these systems, enabling the detection of eventual problems in the upper layer that must be addressed by changing fertilization.

The Sources of Nutrients for the Growing Ear of Winter Wheat in the Critical Cereal Window

The process of winter bread wheat (WW) nutrient management in the Critical Cereal Window (CCW) has a decisive impact on yield component formation and, consequently, the grain yield (GY) and grain protein content (GPC). This hypothesis was verified in a single-factor field experiment carried out in the 2013/2014, 2014/2015, and 2015/2016 seasons. It consisted of seven nitrogen-fertilized variants: 0, 40, 80, 120, 160, 200, and 240 kg N ha−1. The mass of nutrients in ears was determined in the full flowering stage. The mass balance of nutrients (N, P, K, Mg, Ca, Fe, Mn, Zn, and Cu) was determined in leaves and stems. These sets of data were first used to calculate the soil nutrient uptake and then to predict the GY and GPC. Three nutrients, i.e., N, Ca, and Mg, were the main predictors of ear biomass. The set of ear nutrients significantly predicting GY and GE consisted of Ca, P, and Zn. Overall, this indirectly indicates a balanced N status for the ear. A positive nutrient balance in leaves, indicating their remobilization, was found for N, P, Fe, Zn, and Cu. Negative values, indicating a net nutrient accumulation in the non-ear organs of WW, were found for the remaining nutrients. The greatest impact on the GY and its components was observed for the balance of Mg and P but not N. The predictive worth of the nutrient balance for stems was much lower. The GPC, regardless of the type of indicator, depended solely on the N balance. Meanwhile, the main nutrient sources of N and Fe in ears were leaves and stems due to their uptake from the soil. For Cu, the primary source was soil, completed by its remobilization from leaves. For the remaining nutrients examined, the key source for the ear was soil, which was completed by remobilization from leaves and stems. Mg and Ca differed from other nutrients because their source for ears was exclusively soil. They were invested by WW in the ears and non-ear organs, mainly in the stems. The effective use of the yield potential of WW and other cereals requires insight into the nutritional status of the canopy at the beginning of the booting stage. This knowledge is necessary to develop an effective N management strategy and to correct and possibly apply fertilizers to improve both the yield and the GPC.

Strategic Switching from Conventional Urea to Nano-Urea for Sustaining the Rice–Wheat Cropping System

In the face of declining crop yields, inefficient fertilizer usage, nutrient depletion, and limited water availability, the efficiency of conventional NPK fertilizers is a critical issue in India. The hypothesis of this study posits that nano-nitrogen could enhance growth and photosynthetic efficiency in crop plants compared to conventional fertilizers. For this, a randomized block design (RBD) field experiment was conducted with six treatments: no nitrogen (T1), 100% N through urea (T2), and varying levels of N replacement with nano-nitrogen (33%: T3; 50%: T4; 66%: T5; and 100%: T6). Morphological and physiological traits and yield attributes were measured at physiological maturity, and yield attributes were measured at harvest. Results showed that 33% nitrogen replacement with nano-nitrogen (T3) outperformed conventional urea (T2) in physiological traits and achieved higher grain yields (3789 kg/ha for rice and 4206 kg/ha for wheat) compared to T2 (3737 kg/ha for rice and 4183 kg/ha for wheat with 100% urea). Although T4 and T5 showed statistically similar yields, they were lower than T2 and T3 for rice, while 50%, 66%, and 100% replacements reduced wheat yield by 2.49%, 8.39%, and 41.26%, respectively, compared to T2. Key enzymes of N metabolism decreased with higher nano-nitrogen substitution. Maximum nitrogen availability was observed in T2 and T3. This study concludes that nano-nitrogen is an effective strategy to enhance growth, balancing productivity and environmental sustainability.

Simulation and Optimization of a Self-Cleaning Device for the Header of a Rice Seed Harvester Using Fluent–EDEM Coupling

Rice seed production is a critical step in breeding high-quality varieties. To ensure seed purity, it is essential that no residual grains or broken ears remain in the harvester header after harvesting each variety, thus preventing cross-contamination. This study addresses the issue of seed retention in existing rice harvesters, which lack efficient self-cleaning or other cleaning mechanisms and cannot be cleaned rapidly. A self-cleaning device for the harvester header was designed to enable one-click cleaning after harvesting a single variety. A novel cleaning nozzle was developed as the key component of the device, with its structure optimized through single-factor and orthogonal combination experiments. The number of nozzles was determined based on their spray width and the header width. A header-cleaning airflow simulation model based on Fluent–EDEM coupling was constructed to investigate the effects of nozzle inlet pressure, airflow incident angle, and nozzle outlet height on the self-cleaning rate. Optimal cleaning parameters were identified to maximize the self-cleaning rate, and the simulation results were validated. The study revealed that the nozzle’s expansion section length, throat diameter, and contraction section length significantly affect the spray width. When the expansion section length was 10 mm, the throat diameter was 8 mm, and the contraction section length was 8 mm, the nozzle achieved the largest jet angle, measuring 50.3 cm. Further analysis indicated that inlet air pressure had the greatest influence on the self-cleaning rate, followed by airflow incident angle and nozzle outlet height. The optimal parameter combination was identified as an inlet air pressure of 0.6 Mpa, an airflow incident angle of 118.25°, and a nozzle outlet height of 2.64 mm, achieving a maximum self-cleaning rate of 99.63%. A one-click cleaning system was designed using an STM32 microcontroller and hardware circuits. Field experiments under optimal parameters demonstrated a self-cleaning rate of 97.68% with a cleaning duration of 10 s per cycle. The findings provide theoretical guidance for the design and optimization of self-cleaning headers for rice seed production.

Response of Onion (Allium cepa L.) Bulb to the Combined Effect of Vermicompost and Mineral Fertilizer under Irrigated Soil Condition in Raya Azobo and Kilte-Awulaelo Districts South and Eastern Tigray, Ethiopia

Background: In Ethiopia, onion (Allium Cepa L.) is a major vegetable crop. However, due to erratic cultivation, rising mineral fertilizer prices and inadequate soil fertility management, its productivity is declining. Integrated nutrient management is a cost-effective approach to fertilizing soil. If used properly, the combination of vermicomposting with mineral fertilizers is one of the most promising options. Nonetheless, in the study areas, the appropriate application rate of vermicompost and NPSZn fertilizer on onion production has not been well examined. Methods: A field experiment was conducted in the irrigated soil conditions of Kilte-Awulaelo and Raya Azobo districts. The study used a randomized complete block design with three replications and twelve experimental treatments (4.5, 3 and 1.5 t ha-1 vermicompost rates combined with NPSZn 75, 50 and 25 kg ha-1). Full recommended 6 t ha-1 vermicompost, 100 kg ha-1 NPSZn fertilizer and absolute control were used. The collected agronomic data were subjected to ANOVA using SAS statistical software (SAS 9.0) and mean separation was done using LSD. Result: Most of the measured onion growth and yield parameters were significantly affected by the joint application of vermicompost and NPSZn. It varies among districts. Maximum bulb yields of 51.2 t ha-1 in Kilte-Awulaelo and 42.5 t ha-1 in Raya Azobo district were obtained from the application of 4.5 t ha-1 vermicompost with 50 kg ha-1 NPSZn and 4.5 t ha-1 vermicompost with 75 kg ha-1 NPSZn respectively. The combined application of vermicompost with NPSZn fertilizer enhanced onion growth and yield.

Morphological Characterization of Horsegram Genotypes (Macrotyloma uniflorum L. Lam)

Under the provisions of New Seed Policy and the Protection of Plant Varieties and Farmers Rights Act, 2001, all newly developed varieties have to be registered based on the criteria of Novelty, Distinctness, Uniformity and Stability (NDUS) information helps in easy identification of horsegram genotype for each other. In the present study breeder seeds of 24 horse gram genotypes were obtained from pulse breeder, Agricultural Research Station Bailhongal and Regional Agricultural Research Station, Vijayapur for conducting the field experiment at Saidapur Farm University of Agricultural Sciences, Dharwad. The present study was carried out to have information on morphological distinctness of 24 horse gram genotypes for plant height, number of branches, seed coat, flower colour, pod colour, number days taken for pod initiation and pod maturity. All the horsegram genotypes under study were distinguished based on the morphological traits such as days to fifty percent flowering, pod colour and seed coat colour. Among the them seed coat colour and pod colour were most important morphological characters in distinguishing horsegram genotypes as they were least affected by environmental factors. The genotypes differing for. morphological traits serve as markers for maintenance, multiplication and seed certification and also serve as diverse parent for further breeding programe.