Ha-1 Nitrogen Research Articles

Groundnut (Arachis hypogaea L.) Response to Nitrogen Fertilizer and Earthing Up Practices in the Tigray Region of Ethiopia

To increase groundnut yields, integrated agronomic techniques must be implemented. The current study focuses on using starter nitrogen fertilizer in conjunction with earthing up for groundnut cultivation. Three replications and a factorial combination were used in the complete randomized block design of the experiment. Two types of earthing up (no earthing up and earthing up) and four levels of nitrogen fertilizer (0, 15, 30, and 45 kg ha-1) were used in the treatment combinations. For each of the Hamedo 1 and Hamedo 2 experimental sites, two undisturbed and two disturbed composite soil samples were collected at a depth of 20 cm before sowing. The data analysis showed that neither the combination application of N fertilizer and earthing up nor the individual independent applications of N fertilizer and earthing up had a significant effect on groundnut flowering and maturity. Groundnut plant height, number of branches per plant, number of pods per plant, number of seeds per plant, seed weight per plant, and haulm yields were not significantly affected by earthing up alone or by the co-application of nitrogen fertilizer and earthing up. On the other hand, the exclusive use of nitrogen fertilizer significantly affected groundnut plant height, the number of branches per plant, the number of pods per plant, the number of seeds per plant, seed weight per plant, and haulm yield. Applying 45 kg ha-1 of nitrogen fertilizer to the Hamedo 1 and Hamedo 2 trial sites enhanced the haulm yield by 70.53% and 78.76%, respectively, compared to the unfertilized plots. Individual applications of nitrogen fertilizer, earthing up, or a combination of both had a significant effect on groundnut pod and kernel yields. In comparison to plots that received a combined application of 45 kg ha-1 of nitrogen fertilizer and earthing up, the Hamedo 1 and Hamedo 2 trial sites exhibited increases in pod yields of 57.73% and 55.97%, respectively, when earthing up was combined with 15 kg ha-1 of nitrogen fertilizer. In the same way, applying 15 kg ha-1 of nitrogen fertilizer to the earthing-up soil in the Hamedo 1 and Hamedo 2 experimental sites boosted the kernel yields by 70.05% and 75.43%, respectively, in comparison to soil earthing-up plots that received 45 kg ha-1 nitrogen. The findings of the economic and agronomic analyses showed that applying nitrogen fertilizer and earthing up together greatly increases groundnut yields and revenues. Therefore, to increase groundnut yields and receive more financial advantages, farmers can consider the combined application of 15 kg ha-1 of nitrogen fertilizer and earthing-up.

Nitrogen regulated reactive oxygen species metabolism of leaf and grain under elevated temperature during the grain-filling stage to stabilize rice substance accumulation

Rational additional nitrogen is an important agronomic measure to cope with the adverse effects of warming on rice production. However, the mechanism by which nitrogen mitigated the adverse impact of substance accumulation due to elevated temperature is poorly clarified. Therefore, in this study, a field warming experiment during grain filling and 60kg·ha-1 of additional nitrogen was established. Under elevated temperature, panicle temperature was higher and increased more substantially than leaf temperature. However, nitrogen application did not significantly reduce the leaf, panicle, and canopy temperatures. Additional nitrogen under elevated temperature delayed the decline of chlorophyll, maintained leaf photosynthesis, and prolonged grain-filling period to alleviate the decrease of starch due to warming. Hydrogen peroxide (H2O2) was sensitive to elevated temperature in leaves and grains. However, application of nitrogen under elevated temperature improved the activity of antioxidant enzymes to mitigate the increase of H2O2, resulting in a 30.31% and 45.33% decrease of H2O2 in leaves and grains compared to elevated temperature, respectively. Elevated temperature promoted the expression of heat-responsive genes, especially HSP16.9 and HSP26.7, which were consistently increased in response to warming at 5-30d after flowering. In addition, the expression of HSP16.9 at 5d and 10d after flowering and HSP26.7 at 10d after flowering was further increased with nitrogen application under elevated temperature. Therefore, HSP may be the key regulator of grain response to warming with additional nitrogen under elevated temperature. In conclusion, the relevant results revealed the physiological mechanism of nitrogen to guarantee substance accumulation and provided new ideas for cultivation measures to protect against the likely scenario of global warming.

The use of amino acids as bioactive substance: a strategy to increase yield in summer arugula (Eruca sativa L. Mill) crops

Foliar application of amino acids can assist crops to maintain homeostasis under diurnal temperature variations and excessive solar irradiance. The objectives of this study were to investigate the effects of the organic fraction and mineral nutrients of an amino acid solution on arugula plants and the effects of weekly applications of this solution on their growth and biomass yield. Two experiments were conducted in a completely randomized design, in a greenhouse (Experiment 1) and on open-field benches (Experiment 2), in Iracemápolis, SP, Brazil. Experiment 1 consisted of foliar applications of water (control), a solution containing 59 and 40.9 g ha-1 of nitrogen and sulfur, respectively (N+S), and a solution containing 85 g ha-1 of amino acids, with seven replications. Experiment 2 consisted of four different number (0, 1, 2, and 3) of weekly foliar applications of 85 g ha-1 of amino acids, with six replications. Chlorophyll a fluorescence, chlorophyll and carotenoid contents, and fresh and dry biomass weights were evaluated in both experiments. In Experiment 1, shoot fresh weight of plants treated with amino acids increased by 21% and 6% compared to those in the control and N+S treatment, respectively. Amino acid application increased chlorophyll and carotenoid contents, improving photosynthetic performance by increasing effective quantum efficiency of photosystem II and photochemical quenching. In Experiment 2, weekly application of 85 g ha-1 of amino acids increased shoot fresh weight by approximately 10% per application. Therefore, foliar application of amino acids can increase fresh biomass of arugula plants grown under both mild and warmer climate conditions.

Compost de resíduo de feedlot num sistema solo - cultivo de alface

The soil-crop systems of the peri-urban area allow the recovery of chemical elements from the manure generated in intensive livestock production, reducing the risk of contamination of groundwater. This study evaluated the effect of the application of different doses of feedlot waste compost on the lettuce crop (Lactuca sativa L.) and on the chemical, physicochemical, and biological properties of the soil. In two consecutive years, greenhouse experiments were carried out applying doses equivalent to 128 and 500 kg ha-1 of nitrogen, determining fresh weight and apparent efficiency of nitrogen recovery in the crop, and in the soil, nitrate content, organic matter, activity overall biological, electrical conductivity, and pH. The yield of the lettuce crop increased between 29 and 55%, with apparent N recovery efficiencies of less than 5%. In the soil, the effects were mainly manifested in the first centimeters, with increases in the contents of organic matter, global biological activity, and electrical conductivity. On the other hand, there were no significant changes in the pH or nitrate content at depths greater than those reached by the roots of the crop.

Effect of Vermicompost and Inorganic Fertilizer on Physico-chemical Properties of Soil on Cowpea (Vigna unguiculata)

Keeping this in view on experiment is present with the following objective: To evaluate the effect of different doses of vermicompost with NPK on physico-chemical properties of soil. The soil of experimental area falls in order Inceptisol and soil texture was sandy loam (sand % 62.65, silt % 21.09 and clay % 16.26). The design applied for statistical analysis was carried out with randomized block design with three levels of @NPK 0, 50, and 100% ha-1 and three levels of @Vermicopost 0, 50 and 100% ha-1 respectively. The best treatment was effect on physical and chemical property of soil T9 (@100%NPK+ 100% Vermicompost) and yield Attributes T9 (@100%NPK+ 100% Vermicompost) of cowpea. The largest percentages of pore space (%) with depths of 0–15 cm and 15–30 cm, 46.22% and 45.39%, water holding capacity (%) of 42.28% and 43.34%, and organic carbon (%) of 0.40% and 0.38% were found in the post-harvest soil and pre- harvest plant. There were 299.43 kg ha-1 and 293.36 kg ha-1 of available nitrogen, 22.34 kg ha-1 and 21.67 kg ha-1 of available phosphorus, and 179.84 kg ha-1 and 176.43 kg ha-1 of available potassium. The combination of T9-(@100%NPK+100% Vermicompost) demonstrated non-significant differences in particle density (Mg m-3) of 2.45 and 2.47 Mg m-3, pH of 6.89 and 6.91, and EC(dS m- 1) in bulk density (Mg m-3) with depth 0-15 cm and 15-30 cm, which was 1.40 and 1.41 Mg m-3, particle density (Mg m-3) was 2.45 and 2.47 Mg m-3 pH was 6.89 and 6.91 and EC(dS m-1) 0.46 dS m-1 and 0.50 dS m-1.

Seeding and Blended NPSB with Nitrogen Fertilizer Combined Rates Effect on Growth, Yield and Yield Components of Bread Wheat (Triticum aestivum L.) in South Ari, Southern Ethiopia

Wheat is one of the most important cereal crops in South Ari, Ethiopia. However, the productivity is below the national and regional level due to in adequate seeding rates and soil nutrition. Therefore, a study was conducted to determine rate of seeding and blended NPSB fertilizer and nitrogen on growth, yield and yield components of wheat during 2021-2022 cropping seasons. The experiment consisted of three Seeding rates (50, 100, and 150 kg ha-1), four rates of blended NPSB (0,100, 200 and 300 kg ha-1) combined with two rates of Nitrogen (50 and 100 kgha-1) fertilizer and laid out in split plot design with three replications. The results showed that phenology; growth, yield and yield components of wheat significantly affected by seeding rate and blended NPSB with N fertilizer combined rates. Increasing seeding rate and blended NPSB with nitrogen fertilizer combined rate resulted increase in crop phenology, growth, yield and yield components except harvest index where maximum was recorded at 100 kg ha-1 seeding rate and zero blended with 23 kg ha-1 nitrogen combined rate. Therefore, it is concluded that application 100 kg ha-1 seeding rate and no blended NPSB combined with 23 kg ha-1 nitrogen fertilizer and or 150 kg ha-1 seeding rate and 200 kg ha-1 blended NPSB with 23 kg ha-1 combined rate found to be significant to impact wheat growth and yield at South Ari. However, further study requested in different seasons and locations under extended rates to exploit the recommendation of present study.

Bioremediation alternatives for total petroleum hydrocarbon removal in agricultural soil

Objective: The purpose of the present study is to highlight the importance of assessing bioremediation and total petroleum hydrocarbon removal by bioaugmentation and biostimulation on the rhizosphere. Design/methodology/approach: An 89-day experiment was established with treatments considering plant (corn) establishment–crude petroleum (25,000 mg kg-1)–bacteria and hydrocarbonoclastic fungi–adding nitrogen and phosphorus to agricultural soil. At the end of the experiment, hydrocarbonoclastic fungal and bacterial populations and total petroleum hydrocarbon removal were assessed. Results: Both microbial groups increased in number and time. The treatment with 120 kg nitrogen ha-1 and 12.5 kg phosphorus ha-1 allowed the highest population (227 x 103 g-1 of colony forming units (CFU) of hydrocarbonoclastic bacteria). A total of 83% petroleum hydrocarbon removal was obtained as established in 89 days. Limitations on study/implications: The effectiveness of bioremediation can vary significantly in real environments due to factors, such as soil variability, climate. Findings/conclusions: The previous results highlight the importance of using these bioremediation techniques to eliminate hydrocarbons in contaminated agricultural soils.

The Role of Net Assimilation Rate and Nitrogen Management in Optimizing Rice (Oryza sativa L.) Yield

Background: The net assimilation rate (NAR) is a physiological parameter related to leaf area and dry weight per unit of time. It is used to figure out how much grain a plant will produce. This study aims to explain the net assimilation rate of several types of rice at different doses and nitrogen application times. Methods: The research was conducted from December 2021 to April 2022. The experimental design was a split-plot design consisting of two treatment factors: the variety (main plot) and the time and dose of fertilization N (subplot). The variety factor consists of four varieties: IPB 3S (new type varieties), Inpari 33 (new high-yielding varieties), Hipa 21 (hybrids) and Mentik Wangi (local) at nitrogen 4 levels, namely 0 kg ha-1 (N0), 45 kg ha-1 applied when planting (N1), 90 kg ha-1 applied twice [45 kg at planting and 45 kg at panicle initiation (N2)] and 90 kg ha-1 applied three times, namely 45 kg at planting, 22.5 kg at the age of panicle initiation and 22.5 kg at heading (N3). Result: Results demonstrated that applying 90 kg ha-1 nitrogen fertilizer in three split applications (N3) improved agronomic performance by increasing tiller number, leaf area, dry matter accumulation, leaf nitrogen content and grain yield compared to other nitrogen regimes. Our findings newly highlight the vital influence of net assimilation rate (NAR) on panicle development, as NAR was positively correlated with panicle length. Uniquely, among all four varieties tested, the local cultivar Mentik Wangi recorded the highest NAR across N treatments.

Studies on Creation of Operational Range of Soil Fertility to Evolve Fertilizer Prescription Equations under Soil Test Crop Response Correlation Studies on Rainfed Bt Cotton

To derive fertilizer prescription equations for rainfed Bt cotton within the framework of Soil Test Crop Response (STCR) studies, a meticulously designed gradient experiment was executed at the esteemed Cotton Research Station located in Perambalur district, Tamil Nadu, India. Employing a targeted yield methodology, the investigation centered on the cultivation of fodder sorghum as the exhaustive crop during the kharif season. Adhering to an inductive-cum-yield target approach, the experimental plot was meticulously partitioned into three equitably-sized strips, each delineating a distinct fertility gradient. These gradients were meticulously established through the application of varying fertilizer regimes: N0P0K0, N1P1K1, and N2P2K2. Notably, the recommended fertilizer regimen (N1P1K1) encompassed precise quantities of essential nutrients, specifically 60 kg ha-1 of nitrogen (N), 345 kg ha-1 of phosphorus pentoxide (P2O5), and 96 kg ha-1 of potassium oxide (K2O). Fodder sorghum emerged as the strategic choice for the exhaustive crop, strategically cultivated to expedite the transformation of applied fertilizers within the soil matrix, leveraging both plant and microbial processes. The overarching objective of this methodological approach was to establish a discernible operational range of soil fertility across the designated fertility strips. This was meticulously evaluated through meticulous analyses of variations in fodder yield uptake and pertinent soil test values.

Differences of Maize Fodder Yield and Crop Attributes under Different Irrigation and Nutrient Management

Irrigation and nutrient management are two vital components of modern agriculture playing crucial roles in ensuring optimal plant growth, maximizing crop yields and sustaining agricultural productivity. A field trial was conducted to evaluate how irrigation and nutrient management affect the growth characteristics and dry fodder yield of maize. The experiment involved four irrigation levels viz. no irrigation (I0), one irrigation at 20 days after sowing (DAS) (I1), two irrigations at 20 and 40 DAS (I2) and three irrigations at 20, 40 and 60 DAS (I3) and four fertilizer levels viz. recommended dose of fertilizers (RDF) (275-125-80-125-8 kg ha-1 of nitrogen, phosphorus, potassium, gypsum and sulphur) (F1), poultry manure (PM) (5 t ha-1) (F2), 75% RDF + PM (2.5 t ha-1) (F3) and 50% RDF + PM (5 t ha-1) (F4). The study was conducted with a split-plot layout and included three replications. Research results demonstrated significant impacts of both irrigation and nutrient management on growth metrics and the production of dry forage. At harvest, the highest plant height (177.72 cm), number of leaves plant-1 (12.16) and chlorophyll content (47.15) were recorded with three irrigations at 20, 40 and 60 DAS fertilized with 75% RDF + PM @ 2.5 t ha-1 whereas the highest total dry matter (40.60 g) and dry fodder yield (4.51 t ha-1) was recorded with two irrigations at 20 and 40 DAS along with RDF. These results emphasize that maize can produce maximum dry fodder yield with two irrigations at 20 and 40 DAS along with RDF whereas three irrigations at 20, 40 and 60 DAS fertilized with 75% RDF + PM @ 2.5 t ha-1 obtained the superior growth traits of maize.

Effect of Different Levels of Nitrogen on Growth, Yield and Productivity of Wheat (Triticum estivum L.) Cv. Koshan-02

The field experiment was conducted to study the effect of different levels (0, 50, 70, 90 & 110 kg N ha-1) of Nitrogen (N) on growth, yield and yield related parameters of wheat (cv. Koshan-02) in Kabul agro-climate condition at the Agricultural Research Farm of Kabul University, during spring 2020-21. The experiment was laid out in Randomized Complete Block Design (RCBD) with three replications, each replication consisted of five treatments. Total treatments were (15). The size of each plot was (2mx3m=6m2). The result of our study revealed that the plots treated with highest level (110 kg N ha-1) of N fertilizers produced the highest plant height (85.97cm). maximum number of grains spike-1 (35.74), the highest dry matter (3.937t ha-1), The highest number of tillers m-2 (152.76 m-2), 1000-grain weight (48.94g), grain yield (2891.1kg/ha) large spike length (10.52), number of grains spikelet-1 (2.98), Spikelet number spike-1 (11.54), followed by T4, T3 and T2. It was concluded that all treatments have ranked regarding their efficient effects as ((T5 (110 kg N ha-1> T4 (90 kg N ha-1> T3 (70 kg N ha-1> T2 (50 kg N ha_1> TControl) for all growth, yield and yield helping attributes such as plant height, number of grains spike-1, dry matter (kg ha-1), number of tillers plant-1, 1000-grain weight(g), grain yield (kg ha-1), spike length (cm), number of grains spikelet-1, number of spikelet spike-1, spike number m-2 and number of leaves plant_1. So, for obtaining aimed and desirable yield the application of (110 kg N ha-1) is recommended under research area conditions (Agro-Climatic Condition).

Effect of Kharif Paddy Straw Management Options on Nitrogen Requirement to Rabi Paddy

A study conducted during the rabi season of 2020-21 at the Regional Agricultural Research Station, Polasa, Jagtial, under the auspices of Professor Jayashankar Telangana State Agricultural University, yielded insightful findings. The investigation revealed that incorporating paddy straw with a C:N ratio of 71:1 led to the immobilization of soil mineral nitrogen. Specifically, during 7, 15, and 30 days after treatment (DAT), approximately 7.2, 9.3, and 7.03 kg ha-1 of available nitrogen respectively was immobilized without phosphorus, whereas with phosphorus addition, the figures rose to 10.94, 14.75, and 11.04 kg ha-1 during the same time frames. Notably, after harvest of rabi rice significantly higher soil available nitrogen levels were recorded under paddy straw incorporation with phosphorus (169.7 kg ha-1), followed by incorporation without phosphorus (161.2 kg ha-1), and paddy straw burning (151.9 kg ha-1). Moreover, the application of nitrogen at graded levels impacted soil available nitrogen. Based on these findings, it was recommended, to counteract the immobilization effect and maximize crop yield, it was advised to apply 15% excess of recommended dose of nitrogen (RDN), as basal application.

Regulation of photoassimilate transportation and nitrogen uptake to decrease greenhouse gas emissions in ratooning rice with higher economic return by optimized nitrogen supplies

Mechanized harvesting of the main crop rice, with low stubble height in rice ratooning is scaling up, especially in Southeast China with a higher population density and less cultivated land. Currently, the common nitrogen fertilization for ratoon rice is concentrated within 20 days before and after the harvest of the main crop. However, this fertilization pattern may not be suitable for low stubble regenerative rice due to its extended growth period, leading to diminished nitrogen utilization efficiency and heightened greenhouse gas emissions, particularly nitrous oxide (N2O) emissions. It is imperative to explore a nitrogen fertilizer management model for clean production of low stubble ratoon rice (RR). In this study, we examined the effects of nitrogen fertilizer application rates and methods (single or split application) on yield and greenhouse gas emissions during the regrowth season. We employed a multi-criteria assessment approach combined with field measurements, energy analysis, environmental assessment, and economic evaluation on ratoon rice under various nitrogen fertilizer treatments. The results showed that the ratoon rice produced the highest total energy output under 67.5 N+22.5 N (Fertilize with 67.5 kg nitrogen ha−1 and 22.5 kg nitrogen ha−1 3 days after main season rice harvesting and during the heading stage of ratoon rice) treatment compared to the 90 N+0 N (conventional fertilization, apply 90 kg nitrogen ha−1 fertilizer 3 days after harvesting at once) treatment. It was also found that reducing nitrogen application during the tillering stage reduced CH4 emissions, fertilization during the heading stage of the ratoon rice did not increase CH4 emissions, Since fertilization during the heading stage of ratoon rice did not lead to an increase in the partitioning of photoassimilates (photosynthetic product assimilates) to the rhizosphere soil, significant differences in sugar and acetic acid levels were not observed in the rhizosphere soil. As a result, no change was found in the expression of the methanogenic mcrA gene in the microbial community. The study also demonstrated that the 67.5 N+22.5 N treatment was able to promote the absorption of nitrogen nutrients, reduction in N2O emissions by 16.61%, subsequently increasing resource use efficiency, final yield and net ecosystem economic benefit by 5.96%, 7.19% and 5.57%, respectively, thereby decreasing carbon and nitrogen footprints by 6.64% and 3.50% compared with the 90 N+0 N treatment in the ratoon rice. These results suggest that a reasonable ratoon rice cultivation scheme is a promising farming system that can simultaneously improve resource use efficiency and economic profits, reduce greenhouse gas emissions and environmental footprint, while still maintaining the high productivity in ratoon rice.

Interactions of Microbial Inoculations with Fertilization Options and Crop Establishment Methods on Modulation of Soil Microbial Properties and Productivity of Rice

A field investigation was undertaken to assess the interactive effects of different crop establishment methods (CEMs) and microbial formulations in field conditions. The two year experiment was carried out in kharif season (June to October) of both 2013–14 and 2014–15 at Research Farm of ICAR-Indian Agricultural Research Institute, New Delhi India. The CEMs studied consist of puddled transplanted rice (PTR), system of rice intensification (SRI) and aerobic rice system (ARS); while microbial formulations consist of Anabaena sp. (CR1)+Providencia sp. (PR3) consortium (MC1) and Anabaena–Pseudomonas biofilm formulation (MC2). The microbial inoculation was applied with 75% recommended dose of nutrients (RDN) (90 kg nitrogen ha-1 and 19.35 kg phosphorus ha-1) and compared with 100% RDN. Soil microbiological properties showed significantly higher values in SRI in the first year; while in the second year, SRI and PTR remained on par and superior to ARS. Among the combinations of nutrient supplements, application of Anabaena–Pseudomonas biofilm formulation (MC2) with 75% RDN was superior in terms of all microbiological attributes studied [acetylene reduction activity (ARA), soil chlorophyll, soil dehydrogenase activity, microbial biomass carbon and alkaline phosphatase activity]. Application of microbial inoculation led to an increase in milled rice yield from 230 to 240 kg ha-1. Among the different combinations of CEMs and inputs investigated the application of 75% RDN+MC2+zinc (Zn) (soil applied 5 kg Zn ha-1 through zinc sulphate heptahydrate) in SRI can be a judicious option to maximize rice yield and soil health.

Determining the Profitability of Different NPSB and Nitrogen Fertilizer Rates on Yield and Yield Attributes of SweetPotato (Ipomoea batatas L.) in the Midland Areas of Guji Southern Oromia, Ethiopia

Sweet potato is a crucial crop for food security and income generation. Sweet potato vine length, number of stems, average number of roots per plant, average root weight, marketable root yield, non-marketable root yield, and total sweet potato root yield were determined by the NPSB and nitrogen fertilizer application rates (p<0.01). Using the right fertilizer recommendations can improve crop growth and yield while minimizing resource use. Both NPSB and Nitrogen fertilizer rates had a highly significant impact on root number, root weight, marketable root yield, unmarketable root yield, and total root yield. The combination of 100 kg ha-1 NPSB fertilizer and 69 kg ha-1 of Nitrogen fertilizer gave the highest marketable root yield (553.09 qt ha-1). The treatment with 100 kg ha-1 NPSB fertilizer and 46 kg ha-1 Nitrogen fertilizer demonstrated the best result in terms of marginal rate of returns, with a marginal revenue of 17872%. To optimize sweet potato productivity in the Adola rede region, it is recommended to apply 100 kg ha-1 NPSB and 46 kg ha-1 nitrogen fertilizer. In general, cultivation in the Adola rede region can be optimized by applying a combination of 100 kg ha-1 of NPSB fertilizer and 46 kg ha-1 of nitrogen, resulting in improved plant growth and marketability, higher root yields and cost efficiency.

Effect of Chemical Weed Management Practices on Weed Dynamics, Soil Microorganism and Nutrient Uptake in Blackgram [Vigna mungo (L.)

An investigation was carried out at Zonal Agricultural Research Station, Kalaburagi, India, University of Agricultural Sciences, Raichur, Karnataka, India during kharif 2021-22 to study the effect of pre and post emergent application of weedicides on seed yield, weed dynamics, microbial population and nutrient uptake by weeds in blackgram. The results revealed that, significantly lower weed density (grassy weeds, sedges and broad leaf weeds (0.71) and weed dry weight (0.71) was observed with hand weeding at 25-30 DAS and intercultivation at 45 DAS (control) followed by sodium acifluorfen 16.5% + clodinafop propargyl 8% EC @ 1.0 kg a.i. ha-1 at 20-25 DAS [grassy weeds (1.08, 1.26 and 1.83) sedges (1.03, 1.57 and 1.47) and broad leaf weeds (1.72, 2.06 and 2.11 at 25, 50 DAS and at harvest respectively]. Weed control efficiency was significantly higher with sodium acifluorfen 16.5% + clodinafop propargyl 8% EC @ 1.0 kg a.i. ha-1 at 20-25 DAS (89.52, 90.31 and 91.17 at 25, 50 DAS and at harvest respectively) that was on par with hand weeding. Hand weeding at 25-30 DAS and intercultivation at 45 DAS recorded significantly higher population of bacteria, fungi and actinomycetes (13.82, 12.49 and 5.25 cfu x 106 g-1 soil respectively). All chemical weedicides applied either pre-emergent or post-emergent significantly reduced population of total bacteria, fungi, actinomycetes. Significantly higher nutrient uptake by weeds was recorded with weedy check (71.03, 32.00 and 56.67 kg ha-1 nitrogen, phosphorus and potassium respectively). Where as, higher nutrient uptake by blackgram was with hand weeding at 25-30 DAS and intercultivation at 45 DAS (126.25, 28.20 and 109.30 kg ha-1 nitrogen, phosphorus and potassium respectively). After the harvest, soil available nutrients status was higher with hand weeding at 25-30 DAS and intercultivation at 45 DAS (141.38, 42.10 and 298.53 kg ha-1 nitrogen, phosphorus and potassium respectively) and significantly lower nutrients were observed with weedy check (122.93, 30.17 and 220.10 kg ha-1 nitrogen, phosphorus and potassium respectively).

Procena primene azotnog đubriva i nano-silicijum spreja na performanse i komponente prinosa semena suncokreta

Considering the climatic altering and the noteworthy increment within the late seasonal dry stress on sunflower in semi-arid regions, it is fundamental to utilize modern administration like application nano silicon to reduce the unfavourable impacts of such stresses. A field trial was performed to study the effects of nitrogen levels (40, 80, and 120 kg ha-1 ) and foliar spray treating of nano silicon (50, 100, and 150 ppm) on some traits of sunflower. The first two factors explained 79% of the variation and showed strong positive association of yield and thousand-seed weight. The N4-Si3 (120 kg ha-1 nitrogen plus 150 ppm nano silicon) indicated the higher values for most traits, leaf and head properties and seed yield. For confirmation findings of factor analysis, the clustering of traits and treatments was performed and categorized the measured traits and treatments into three clusters. The medium and high concentrations of nitrogen and nano silicon (80 and 120 kg ha-1 nitrogen; 100 and 150 ppm nano SiO2) were grouped with each other in the same cluster and were the best treatments. The nitrogen is one of the important fertilizers for sunflower production and low magnitudes of nitrogen could not be sufficient in semiarid environments. The nano silicon has beneficial ability to minimize the harmful influences of environmental stresses and can provide the goals of sustainable and low input agricultural systems in production of sunflower under semi-arid regions.

Enhancing bulb yield through nitrogen fertilization and the use of hybrid onion (Alluim cepa L.) varieties in northwest Ethiopia.

Onions are among the most important cash crops in developing countries, including Ethiopia. However, its production and productivity are very low, which is associated with inappropriate fertilization and the use of low-yielding varieties. Therefore, the present study was conducted to evaluate the effects of the nitrogen fertilizer rate on the growth, yield, and quality of hybrid onion varieties in northwest Ethiopia. The experiment was conducted at three locations (Koga, Woreta, and Woramit) during the 2021/2022 cropping season under irrigated conditions. The treatments consisted of three hybrid onion varieties (Russet, Jambar, Red Coach) and one open-pollinated onion variety (Bombay Red) and four nitrogen rates (0, 41, 82, and 123 kg ha-1), which were laid out in a randomized complete block design with a factorial arrangement of 4*4 in three replications. The results of the present study revealed that onion growth, yield and quality were influenced by the nitrogen fertilizer rate and onion variety across all locations. Compared with the open pollinated Bombay Red variety, the hybrid varieties (Russet and Jambar) performed well in terms of bulb diameter, bulb weight, total yield, marketable bulb yield, and pungency. Nitrogen fertilizer applied at a rate of 82 kg ha-1 resulted in the highest growth and yield parameters of onion. The Russet and Jambar varieties recorded the highest marketable bulb yields of 26.50 t ha-1 and 24.57 t ha-1, respectively. Onion varieties treated with the highest nitrogen fertilizer dosage of 123 kg ha-1, particularly the Bombay Red variety, exhibited the longest duration to reach maturity. Onion plants supplied with 82 kg ha-1 nitrogen presented the highest marketable bulb yields, with a value of 26.77 t ha-1. Too much nitrogen above 82 kg ha-1 leads to decreased yield; hence, excess nitrogen is lost to the environment. Furthermore, the Jambar and Russet hybrid varieties and the application of 82 kg ha-1 nitrogen fertilizers provided the highest net benefit. The hybrid varieties Jambar and Russet and the application of 82 kg ha-1 nitrogen fertilizer can be recommended for onion production in the study area and areas with similar agroecosystems. Since this study is the first of its kind, considering other hybrid onion varieties and optimizing agronomic practices such as spacing and phosphorus fertilizer are also recommended in future research.

Performance of Grafted Bitter Gourd (Momordica charantia L.) at Different Pruning and Nitrogen Levels in Nawalparasi East, Nepal

Pruning and level of nitrogen influence the growth and yield of bitter gourd. A field experiment was conducted to assess the effect of different pruning and nitrogen levels on the growth and productivity of bitter gourd from March to July 2022 in Nawalparasi East, Nepal. The field experiment was laid out in a split-plot design with three replications. The treatment comprised three levels of pruning (No pruning, second generation (2G) pruning, and third generation (3G) pruning) in main plots and three different doses of nitrogen (100, 150, and 200 kg ha-1) in sub-plots. Observations on growth, floral, and yield parameters were recorded, analyzed, and presented. The research result revealed that 3G pruning with 200 kg ha-1 nitrogen level produced the highest fruit yield (16242.56 kg ha-1) at the fourth harvest. The yield trend showed higher fruit yield at higher nitrogen levels and 3G pruning at all dates of harvest. The increased fruit yield at higher nitrogen levels was because of more number of fruits per plant as well as longer fruit length and larger fruit diameter. The higher productivity in 3G pruning was mainly due to more fruit per plant at the fourth harvest. The results indicate a higher yield of bitter gourd at a higher level of nitrogen with 3G pruning.

INTERACTION OF NITROGEN AND PLANT DENSITY ON GROWTH AND YIELD OF TWO QUINOAS (Chenopodium quinoa Willd.) CULTIVARS IN FARS PROVINCE, IRAN

As a field crop, quinoa (Chenopodium quinoa Willd.) has great potential in improving food for humans and animals even under marginal lands. Experiments were carried out at Marvdasht, Iran, in 2017 and 2018 main crop growing season to evaluate the effect of 4 levels of nitrogen (0, 75, 150, and 225 kg/ ha), three levels of density (20, 30, and 40 plants /m2), and two cultivars of quinoa (Titicaca and Sajema). The factorial experiment was performed based on a randomized complete block design with three replications. The results showed that nitrogen fertilizer significantly affected all measured traits. By increasing the nitrogen and plant density, the plant height, grain yield, and biological yield increased. The highest harvest index and nitrogen use efficiency was obtained from the highest density level. In all studied traits, Titicaca cultivar had greater than Sajema. Due to the superiority of 225 kg /ha-1 of nitrogen and the density of 40 plants/m2 in terms of grain yield, it seems that this amount of nitrogen fertilizer and planting density to achieve good yields in the test and similar areas is also recommended. Also, the higher seed yield in Titicaca cultivar than Sajema is recommended for planting in the studied areas.