Nitrogen Fertilizer Treatments Research Articles

Nitrogen Fertilizer Programs for Organic Flue-Cured Tobacco (Nicotiana Tabacum L.) Seedling Production

Certified organic flue-cured tobacco (Nicotiana tabacum L.) production has experienced significant expansion in the United States. Despite this expansion, there is very little information available that outlines organic nitrogen (N) programs for seedling production. To develop grower recommendations, research was conducted to evaluate the effects of a Peruvian seabird guano (SG), sodium nitrate (SN), or a combination of the two (SN_SG) in a float system on float water chemistry and seedling vigor. A conventional treatment (Conv; SQM Ultrasol Premium) was included for comparison. A greenhouse study was conducted twice between June 2016 and January 2017. Nitrogen fertilizer treatments were applied to tobacco float system water twice during the germination and growth of tobacco transplants. Float system water was collected every 5 days and analyzed for N forms, pH, dissolved oxygen, and bicarbonate. At the end of each experiment, transplant dimensions were measured and percent of usable plants collected. Float water bicarbonate concentration was <1 meq L−1 in treatments absent of SG for the duration of the study, but were in excess of 12 meq L−1 25 days after seeding (DAS) when SG was the exclusive N source. Despite high ammonium and bicarbonate concentrations with SG, neither factor negatively impacted seedling growth. Both SG and SN_SG produced as many usable plants as Conv; however, seedling height and diameter tended to be lower in SG compared to the other two treatments. No usable transplants were produced when SN was the sole fertility source, likely because of lack of nutrients other than N. Furthermore, many of the organic fertility products require biological activity to mineralize organic N to a plant-available form. This activity can have potentially detrimental outcomes on float system solution pH, dissolved oxygen, and bicarbonate levels.

Long-Term Tillage and Nitrogen Fertilization for Soybean on Gley Soil

During three years (2007, 2008 and 2009), multidisciplinary stationary research of reduced soil tillage and nitrogen fertilization was conducted for soybean [Glycine max (L.) Merr.], on Gley soil type of Croatian Baranya region. Research was carried out with four soil tillage treatments and three nitrogen fertilization level, set up as split-plot design in four repetitions. Tillage treatments (TT) were: CT- conventional tillage (autumn plowing 30 cm), DT- multiple disk-harrowing (autumn disk-harrowing 10-12 cm), LT- chiselling and disk-harrowing (autumn soil loosening 30 cm), NT- no-tillage. Nitrogen fertilization treatment (NF) for soybean was NF-1 = 35, NF-2 = 70, NF-3 = 110 kg N/ha. Weather conditions during the study were adverse with considerable aberrations, respectively significantly different from long-term mean. Thus, 2007 was extremely dry, 2008 was moderately humid and 2009 dry. Significant differences of soil water content (SWC) were identified in all years of research: NT had higher SWC in 2007 and 2008, while DT had hogher SWC in 2009 compared to CT. The yield was negatively statistically significant correlated with bulk density (BD), i.e. with increase of compaction yield decreased. Significant differences among years were recorded regarding soybean grain yield, whereas soil tillage systems showed following decreasing order, on average: CT (2.59 t/ha) > LT (2.46 t/ha) > NT (2.46 t/ha) > DT (2.41 t/ha). Nitrogen fertilization on average did not influence soybean yield. On average, compared to CT, only DT had significantly lower soybean grain yield. The study showed a very successful application of reduced soil tillage systems in soybean production with the optimal nitrogen fertilization.

Reuse in the agro-industrial: Irrigation with treated slaughterhouse effluent in grass

Abstract The animal slaughter and meat processing industries generate large sources of effluents, rich in organic matter that can be used in plants irrigation as strategy in order to reuse water in agricultural properties. The objective of this work was to evaluate the production and the composition of coastcross grass for hay production by sprinkler irrigation with urea effluent treated by the anaerobic exercise. The experimental was developed in randomized blocks, with five treatments and four replicates (5 × 4), with time subplots. The five treatments used were: (i) T1 - irrigation with surface water plus 50.0 kg ha−1 cut−1 nitrogen fertilization (NF) provided as urea; (ii) T2, T3, T4 and T5 - irrigation with treated slaughterhouse effluent (TSE) plus 0, 16.5, 33.0 and 50 kg ha−1 cut−1 NF. The variables analyzed were the production of fresh and dry mass, soil chemical characteristics and prospective and bromatological analysis, during the winter and the summer. After the treatment, the effluent showed elevated concentration of total nitrogen (176.00 ± 52.32 mg L−1) and a low to moderate saline potential (EC = 1.46 ± 0.34dSm−1). In the winter the nutritional status and the coastcross grass production were kept by irrigation with the effluent, compared with the surface water treatment saving 100% of the nitrogen fertilization. The percentage of phosphorus, sodium and base saturation of the soil were altered by the wastewater. During the summer, the irrigation sludge with effluent were reduced due to rainfall inhalation, with less nutrients support. The higher precipitation occurrency at this season reduced the total amount of salt in the soil. The total production (winter and summer) of dry mass and fresh dough were superiors with the 100% NF treatments, regardless of the water source.

Nitrogen and chlorophyll status determination in durum wheat as influenced by fertilization and soil management: Preliminary results.

Handheld chlorophyll meters as Soil Plant Analysis Development (SPAD) have proven to be useful tools for rapid, no-destructive assessment of chlorophyll and nitrogen status in various crops. This method is used to diagnose the need of nitrogen fertilization to improve the efficiency of the agricultural system and to minimize nitrogen losses and deficiency. The objective of this study is to evaluate the effect of repeated conservative agriculture practices on the SPAD readings, leaves chlorophyll concentration and Nitrogen Nutrition Index (NNI) relationships in durum wheat under Mediterranean conditions. The experimental site is a part of a long-term-experiment established in 1994 and is still on-going where three tillage managements and three nitrogen fertilizer treatments were repeated in the same plots every year. We observed a linear relationship between the SPAD readings performed in the central and distal portion of the leaf (R2 = 0.96). In fertilized durum wheat, we found all positive exponential relationships between SPAD readings, chlorophyll leaves concentration (R2 = 0.85) and NNI (R2 = 0.89). In the unfertilized treatment, the SPAD has a good attitude to estimate leaves chlorophyll concentration (R2 = 0.74) and NNI (R2 = 0.77) only in crop grow a soil with relative high content of soil organic matter and nitrogen availability, as observed in the no tilled plots. The results show that the SPAD can be used for a correct assessment of chlorophyll and nitrogen status in durum wheat but also to evaluate indirectly the content of soil organic matter and nitrogen availability during different growth stages of the crop cycle.

Effects of Nitrogen Management on Soil Nitrogen Content and Rice Grain Yield in Double Cropping Rice Production Area with Continuous Full Amount of Straw Returning

ABSTRACTIn order to formulate a nitrogen (N) management strategy under continuous full amount of straw returning (CFSR) for double cropping rice production, long-term (2013–2016) paddy field experiments were conducted in double cropping rice production area in the Jiangxi province, China. Five N fertilizer treatments under CFSR were tested, that is, (i) no N fertilizer application (CK); (ii) conventional N fertilizer application (165kg N ha−1 and 195 kg N ha−1 in early and late rice variety with the ratio of basal dressing to topdressing as 6:4, respectively) (CNF6:4); (iii) recommended N fertilizer application (135 kg ha−1 N and 165 kg ha−1 N in early and late rice variety with the ratio of basal dressing to topdressing as 4:6, 6:4, and 8:2, respectively) (RNF4:6, RNF6:4, and RNF8:2). Nitrogen fertilizer treatments under CFSR had 5.70% and 8.93% higher soil total nitrogen (TN), 1.32% and 0.80% higher available nitrogen (AN), 16.55% and 22.94% higher NH4+-N, and 13.10% and 7.93% higher NO3--N than CK treatments in early and late rice variety, respectively. There were no differences in soil TN, AN, NH4+-N, and NO3--N contents between CNF6:4 and RNF6:4 treatments, while CNF6:4 treatment showed higher or significantly higher soil N contents than RNF4:6 and RNF8:2 treatments. N fertilizer treatment under CFSR showed 88.9% and 43.20% higher grain yield and 62.15% and 42.52% higher panicle numbers than CK treatments in early and late rice variety, respectively. Compared with CNF6:4, RNF treatments did not significantly reduce grain yield and yield components in early and late rice variety, respectively, except for RNF8:2. Compared with RNF6:4 and 8:2, RNF4:6 showed higher rice grain yield, while no obvious differences in yield components were obtained among all RNF treatments. We concluded that N fertilizer under CFSR was helpful to improve soil N contents and double rice grain yield and panicle numbers. Appropriate reduction of N application (18% and 15% reduction in early and late rice variety, respectively) on the basis of adjusting ratio of basal dressing to topdressing as 4:6 and 6:4 did not significantly reduce soil TN and double rice grain yield and yield components, especially, the 40% basal N dressing and 60% N topdressing was beneficial to increase double rice grain yield under CFSR.

Long-Term N Fertilization Decreased Diversity and Altered the Composition of Soil Bacterial and Archaeal Communities

Soil microbial communities are essential in the cycling of nutrients that affect crop production. Our goal was to characterize the microbial community structure following 34 years of nitrogen (N) fertilization treatments in continuous maize production in highly fertile soils. Using 16S rRNA gene-based analysis of the V4 region via Illumina HiSeq2500 technology with downstream bioinformatics processing and analysis with QIIME 2.0, we aimed to characterize the prokaryotic communities under three increasing N fertilization rates. Factor analyses indicated that a high N level decreased the diversity of soil bacterial and archaeal communities and altered the relative abundance (RA) of the dominant (>1% RA) and minor (<1% RA) phyla. Among the 12 major phyla, we determined increases in Gemmatimonadetes, Proteobacteria, and Euryarchaeota, accompanied by reductions in Cyanobacteria, Chloroflexi, Firmicutes, and Planctomycetes with increasing N. Within the 29 minor phyla, N fertilization led to increases in Aquificae, WPS2, Parvarchaeota, AD3, FCPU426, Armatimonadetes, TM7, Chlamydiae, and OD1, along with reductions of Nitrospirae, WS3, Tenericutes, Lentisphaerae, OP3, Synergistetes, Thermotogae, and prokaryotes that could not be reliably assigned to a phylum (classified as Other).

Towards Improving the Vegetative and Qualitative Traits of Sunflower Using Amending Soil (Zeolite and Manure Farmyard) under Water Deficit Stress

ABSTRACTThe effect of different sources of nitrogen fertilizers (organic fertilizers and urea) and zeolite under different irrigation regime on the qualitative traits of sunflower seeds was investigated by a trial, in 2014 and 2015 in Iran with split factorial on a randomized complete block design with three replications. Main plots consisted of irrigation regimes (irrigation after unloading 40%, 60% and 80% of available soil water (ASW)). The sub-plots consisted of factorial combinations of three nitrogen fertilizer treatments (100% organic, integrated treatment and 100% chemical treatment) and three levels of zeolite (10, 5 and 0 ton ha−1). Farmyard manure and urea were the organic and chemical sources of nitrogen, respectively; integrated treatment included 50% organic +50% chemical nitrogen. The percentage of nitrogen required by urea was set in a way that 100% of the required nitrogen could be provided by urea. The maximum diameter and stems height as well as the performance of the oil and protein by application of zeolite were measured in terms of the lack of stress in the first and second year, respectively. In sum, it can be concluded that the severe water stress can reduce the percentage of unsaturated fatty acids. In the first year, oleic acid and linoleic acid were decreased by 22% and 7%, respectively; while in the second year, they were reduced by 27% and 6.8%. Stearic acid also declined in the first and second years by 50% and 52%, respectively. However, an increase was observed for palmitic acid of sunflower. In both years, the application of organic fertilizer increased linoleic acid and oleic and improved the quality of sunflower seed oil. Under favorable irrigation conditions, organic fertilizers could be advantageous; while organic fertilizers and zeolite can be helpful under drought stress conditions.

Integrated use of straw mulch with nitrogen fertilizer improves soil functionality and soybean production

Mulching can effectively maintain and improve soil health and functionality. The mechanisms, however, have not been fully elucidated. Therefore, the effects of temperature on the biogeochemical properties of soil were investigated in the present study in relation to nitrogen management and soil functionality. The results of the 3-year field experiments showed that integrated straw mulch (S) and nitrogen fertilizer (N) treatments enhanced the activities of soil urease, invertase, alkaline phosphatase, and catalase by >1.8, 2.1, 2.0 and 1.4 fold, respectively, compared with the control treatment. Furthermore, these treatments increased soil available N by 28%, phosphorus by 45%, and potassium by 55%. In general, the soil organic carbon, dissolved carbon and labile organic carbon content in the treated plot were approximately 1.2–2.9 folds greater than in the control plot. These improvements in soil fertility and carbon indices increased the biomass and grain yield of soybean (67 and 75%, respectively) during the three-year study period. During 2015–2017, the straw mulch and nitrogen fertilizer treatment increased the soil moisture (23%) and decreased the soil temperature (8%) in comparison to the control in the 0–0.2 m soil depth and, therefore, improved soil enzyme activities, nutrient availability, and carbon stocks, and ultimately, soil functionality and sustainability, in the semiarid region.

Effects of water deficit and different nitrogen fertilizer treatments on the quality of wheat for Chinese fresh white noodles and steamed bread and the composition of storage proteins.

Noodles and steamed bread are popular wheat products consumed worldwide, particularly in China and other Asian countries. We performed the first comprehensive study of the influence of water deficits and different nitrogen fertilizer applications on two elite Chinese bread wheat cultivars, Zhongmai 175 and Jimai 22, which are distinct in gluten strength. These wheat cultivars were tested to determine the qualities that are optimal for the production of Chinese fresh white noodles (CFWN) and northern-style Chinese steamed bread (NCSB), and storage protein composition. Water deficit and high nitrogen (N) fertilizer application promoted total grain protein content and the accumulation of gliadins and glutenins, while low N resulted in the opposite results. Water deficit and high N fertilizer in Jimai 22, with medium-to-strong gluten strength significantly improved NCSB and CFWN qualities. The quality of CFWN under low N, and that of NCSB under both high and low N conditions, was significantly reduced. However, NCSB and CFWN quality in Zhongmai 175 with weak-to-medium gluten strength was not significantly affected by water deficit and different N fertilizer applications. Grain subproteome analysis revealed that considerable cultivar-specific gliadins and glutenins showed significant accumulation changes in response to water deficit and high / low N fertilizer treatment, which could be responsible for NCSB and CFWN quality changes under different treatments. Water deficit and high / low N fertilizer treatments caused changes in cultivar-specific storage protein composition, resulting in differences in the accumulation of gliadins, glutenins, and the quality of NCSB and CFWN. © 2019 Society of Chemical Industry.

Effects of Nitrogen Fertilization and Seed Piece Applied Fungicides on Establishment, Tiller Dynamics, and Sucrose Yields in Successively Planted Sugarcane

Sugarcane (Saccharum spp.) successive planting causes 25–30% yield reduction in comparison to fallow or rice rotation planting in a three-year production cycle on Florida Histosols. Field experiments were established to manage the yield losses associated with successive planting through nitrogen fertilization and seed piece application of fungicides in plant and first ratoon crops each at two sites. Nitrogen fertilization treatments included 0 (N0), 50 (N50), and 100 (N100) kg ha−1 applied in furrows at the time of planting, and one split application (N50+50) with 50 kg ha−1 applied at planting and 50 kg ha−1 applied at 90 days after planting as side-dress. Fungicides treatments were mancozeb at 2.5 kg a.i. (active ingredient) ha−1, mefenoxam at 0.57 kg a.i. ha−1, and azoxystrobin at 0.30 kg a.i. ha−1 applied to seed cane pieces laid in the furrows at planting. Nitrogen fertilization showed increasing trends of the tiller and millable stalks production in plant and ratoon crops. N response varied with the time of ratooning. Overall, N50+50 produced greater tons of cane per hectare (TCH) and tons of sucrose per hectare (TSH) compared to other N treatments in plant crop and late season ratoon crop (ratooned in March). N100 treatment enhanced tillering and TCH in December ratooned crop. In 2016 plant crop, mefenoxam produced higher TCH than others, but no carryover effects were observed in ratoon crops. Both nitrogen fertilization and fungicides seem to be promising cultural practices to minimize yield losses in successive sugarcane planting in Histosols.

Nitrogen and carbon management in Australian mango orchards to improve productivity and reduce greenhouse gas emissions

Australian mango orchards, particularly of the 'Kensington Pride' cultivar, are often characterized by low yields and irregular bearing. Improved nutrition management techniques which increase total soil carbon sequestration and reduce nitrogen losses (nitrous oxide) may improve productivity and also reduce greenhouse gas emissions. A factorial trial was established in a 'Kensington Pride' mango orchard at Mareeba, Australia to assess the benefits of applying organic hay mulch to tree rows in combination with three nitrogen fertiliser treatments including two controlled-release fertiliser products. Three years after the initiation of treatments it was found that mango tree growth and fruit productivity was significantly improved when mulching was used to increase soil organic matter. Mulched soils had improved soil water holding capacity, less temperature variability, increased root biomass in the top soil, greater canopy leaf area and higher plant tissue potassium levels. Average fruit weights were increased by 10% and mango fruit yields per tree increased by 11%. Fruit quality was not affected when standard fungicide management treatments were used, although disease levels were higher with no post-harvest fungicide treatment. The nitrogen fertiliser products investigated did not have a significant influence on mango growth or final productivity. Trial results suggest that the adoption of mulching practices in mango orchards is a management practice which can increase orchard productivity and the sequestration of soil organic carbon, without detrimental effects on fruit quality.

Monitoring sugarcane growth response to varying nitrogen application rates: A comparison of UAV SLAM LiDAR and photogrammetry

The capabilities and utility of UAV LiDAR and surface from motion photogrammetry have been of wide discussion in the remote sensing community and assumptions made, often speculative, about the potential strengths and limitations of these systems. Here, we employ a side-by-side test of the CSIRO Hovermap LiDAR and Micasense RedEdge multispectral camera simultaneously mounted to a single UAV platform to acquire a time-series data set from both sensors over the growth cycle of a sugarcane crop in northeast Queensland, Australia. The primary aim was to compare the ability of each system to accurately measure crop height, over a single growing cycle. A secondary aim examined the correlation between these measures and the sugarcane biophysical parameters of stalk population (stalks·m−2), total fresh biomass (TFB, t·ha-1) and cane yield (Yield, t cane·ha-1). The experimental design included a randomised complete block design of four nitrogen fertiliser treatments (0, 70, 110, 150 and 190 Nkg·ha-1) with four replications to assess if either optical measure could detect significant effects of nitrogen application on crop growth. Both systems demonstrated similar capabilities for accurately measuring crop heights throughout the growth period with statistically significant coefficients of determination observed when comparing the maximum (AdjR2 = .885, F(1,118) = 910.806, p ≤ .001) and mean (AdjR2 = .929, F(1,118) = 1548.404, p ≤ .001) crop height estimations of both instruments. In addition, both systems responded similarly in the detection of differences in crop structural properties response to nitrogen treatments. Only Hovermap, however, demonstrated the capacity to obtain sufficient ground returns over the course of the growth period to enable comparisons to the biophysical samples using a ground-to-non-ground return ratio (Stalk Population:AdjR2 = .788, F(1,18) = 70.688, p ≤ .001, TFB: AdjR2 = .713, F(1,18) = 48.198, p ≤ .001, Yield:AdjR2 = .707, F(1,18) = 46.921, p ≤ .001) with the best results of RedEdge obtained when comparing mean height measures (Stalk PopulationAdjR2 = .502, F(1,18) = 20.172, p ≤ .001, TFB: AdjR2 = .309, F(1,18) = 9.481, p = 0.006, Yield: AdjR2 = .322, F(1,18) = 10.028, p ≤ .005). The results suggest that although both systems are comparable for accurate crop height measurements, and as such, provide early detection of potential problems, UAV LiDAR provided more consistent and significant correlations with optical remotely sensed data to the biophysical parameters of sugarcane.

Balance of potassium in two long-term field experiments with different fertilization treatments

Balance of potassium (K) was observed in long-term stationary field experiments (21 years) at two sites with different soil and climatic conditions (Luvisol, Cambisol). The following crops were rotated within the trial: potatoes- winter wheat-spring barley. All three crops were grown each year. The trial comprised 6 treatments: (1) no fertilization; (2) farmyard manure; (3) half dose of farmyard manure + nitrogen (N) in mineral nitrogen fertilizers; (4) mineral nitrogen fertilizers; (5) NPK in mineral fertilizers; (6) straw of spring barley + N in mineral nitrogen fertilizers. The recovery rate of potassium from farmyard manure by crops was 24–26%, from mineral fertilizers it was 27–52%. Different fertilization intensities were manifested by significant differences in the content of exchangeable K in soil. Changes in non-exchangeable K (K<sub>ne</sub>) were recorded only at the Luvisol site (850 mg K<sub>ne</sub>/kg), but not at the Cambisol site (3000 mg K<sub>ne</sub>/kg). The maximum negative balance (–2376 kg K/ha/21 years) was recorded at the mineral nitrogen fertilization treatment.

Dynamic changing of soil water in artificial ryegrass land in the hilly regions of Sichuan Basin area

To understand the impacts of fertilizer treatment and ryegrass growth on the dynamic changes of soil water is essential to use available soil water and rainfall sagaciously and develop a sustainable artificial ryegrass land in Sichuan Basin area and the similar areas in the world. In the current research, the dynamic changes of soil water were measured under different nitrogen fertilizer treatments by field experiment and EPIC model (Environment Policy Integrated Climate) simulation in the hilly region of Sichuan Basin area from 2011 to 2015. Results revealed that the EPIC model simulated the dynamic changes of soil water well, as the simulated and observed values of forage yield, leaf area index and ryegrass height exhibited a good correlation. When the nitrogen fertilizer was 150 kg/hm2 the soil water consumed by ryegrass during January to May period recovered well during June to September, it is more sustainable treatment than other experimental treatments, considering in a long period. Furthermore, our simulation demonstrated that the roots especially distributed in 0–50 cm soil has a significant effect on available soil water in 0–1 m soil. Root distributed in 0–20 cm and 60–100 cm soil affected the available soil water in 0–50 cm and 60–100 cm soil respectively.

Water effects on optical canopy sensing for late-season site-specific nitrogen management of maize

The interpretation of optical canopy sensor readings for determining optimal rates of late-season site-specific nitrogen application to corn (Zea mays L.) can be complicated by spatially variable water sufficiency, which can also affect canopy size and/or pigmentation. In 2017 and 2018, corn following corn and corn following soybeans were subjected to irrigation × nitrogen fertilizer treatments in west central Nebraska, USA, to induce variable water sufficiency and variable nitrogen sufficiency. The vegetation index-sensor combinations investigated were the normalized difference vegetation index (NDVI), the normalized difference red edge index (NDRE), and the reflectance ratio of near infrared minus red edge over near infrared minus red (DATT) using ACS-430 active optical sensors; NDVI using SRS-NDVI passive optical sensors; and red brightness and a proprietary index using commercial aerial visible imagery. Among these combinations, NDRE and DATT were found to be the most suitable for assessing nitrogen sufficiency within irrigation levels. While DATT was the least sensitive to variable water sufficiency, DATT still tended to decrease with decreasing water sufficiency in high nitrogen treatments, whereas the effect of water sufficiency on DATT was inconsistent in low nitrogen treatments. A new method of quantifying nitrogen sufficiency while accounting for water sufficiency was proposed and generally provided more consistent improvement over the mere averaging of water effects as compared with the canopy chlorophyll content index method. Further elucidation and better handling of water-nitrogen interactions and confounding are expected to become increasingly important as the complexity, automation, and adoption of sensor-based irrigation and nitrogen management increase.

Comparative Proteomic Analysis Unveils Critical Pathways Underlying the Role of Nitrogen Fertilizer Treatment in American Elderberry.

American elderberry (Sambucus nigra subsp. canadensis) is a rapidly growing specialty crop in Missouri and eastern North America. Nitrogen (N) is a major nutrient involved in plant growth and development. However, proteome changes for different genotypes of elder in response to varying levels of N-treatment remain undefined. To reveal plant responses to N, comparative proteomic analyses were performed to determine consistent changes in three genotypes of elderberry leaves (Adams II, Bob Gordon and Wyldewood) grown under different N-fertilizer treatments. 165 proteins separated by two dimensional gel electrophoresis showed significant differences in abundance (p < 0.05 and greater than 2-fold). Principal component analysis of the abundance profiles of these proteins revealed Bob Gordon as a distinct genotype. The 165 proteins were identified by mass spectrometry and showed similar functional distributions in these genotypes underlying the N-treatment. Among the proteins identified, 23 are mainly involved in photosynthesis, protein metabolism and redox homeostasis. Their abundance profiles were not altered upon exposure to N or genotype. These results provide novel insights into plant responses to fertilizer treatment at the proteome level and could lead to a better understanding of molecular mechanisms of elderberry growth.

Effect of inoculation of two Aztobacter and nitrogen fertilizer on of peppermint (Mentha piperita) essential oil

Abstract. Bidgoli RD. 2019. Effect of inoculation of two Aztobacter and nitrogen fertilizer on of peppermint (Mentha piperita) essential oil. Asian J Agric 3: 22-25. This study was conducted to study changes of percentage and yield of essential oil of peppermint (Mentha piperita) as a split factorial in a randomized complete block design (RCBD) with three replications in 2016-2017. The experimental treatments were nitrogen at four levels 0, 50, 100 and 150 kg/ha as the main factor and two strains of PGPR (Aztobacter chroococcum MZ11, MZ26) in two state of (use and non-use) was considered as sub factors. Results showed that use of these two of A. chroococcum strains has led to increase in the percentage and yield of peppermint essential oil more than all Nitrogen fertilizer treatments. Also, the highest peppermint essential oil percentage (0.73%) obtained the in the of triple interaction of Nitrogen (100 kg/ha) A. chroococcum MZ11 and A. chroococcum MZ26 The highest essential oil yield (91.65 kg/ha)observed under the influence of the triple interaction of Nitrogen (100 kg/ha) , A. chroococcum MZ11 and A. chroococcum MZ26.

Effects of Fertilization on the Nitrogen Residual Amounts and Leaching from Citrus Orchard Soil in the Three Gorges Reservoir Area

This experiment has the citrus orchard soil in the basin of the Zigui County Ecological Station in the Three Gorges Reservoir Area as its research object. Leaching tests of an undisturbed soil column at 0-20, 0-40, and 0-60 cm depth were performed in a citrus orchard. The effects of nitrogen leaching and residual amounts in the soil were studied. Four kinds of fertilization treatments were set up in the experiment:no fertilization treatment (CK), low nitrogen fertilization treatment (T1:250kg·hm-2), medium nitrogen fertilization treatment (T2:500kg·hm-2), and high nitrogen fertilization treatment (T3:750kg·hm-2). The results showed that:① The main form of nitrogen leaching in citrus orchard soil was nitrate nitrogen (NO3--N), accounting for 36.93%-60.07% of total nitrogen (TN) leaching. The ratio of TN to ammonium nitrogen (NH4+-N) was 4.40% to 5.79%. The ratio of NO3--N residues in soil to TN residues was 11.31‰-45.66‰, and the ratio of NH4+-N residues to TN residues was 1.051‰-2.07‰. ② Nitrogen leaching and residual amounts in citrus orchards at the same depth showed significant positive correlation with the amount of fertilizer applied. The leaching losses and residual amounts of TN in soil at different fertilization rates were 11.35-30.11 kg·hm-2and 0.30-1.86 g·kg-1, respectively. Among them, the ratio of leaching losses of NO3--N and NH4+-N to TN leaching amounts peaked under T2 treatment, and the peaks of NO3--N and NH4+-N residues in TN residual amounts appeared in T1 and T2 treatment, respectively. ③ Given the same fertilization amounts, the leaching amounts and residual amounts of different forms of nitrogen in the soil were greatly affected by soil depth. After fertilization, the peaks of NO3--N leaching and residual amounts appeared at 20 cm and 40 cm, respectively, and the peaks of NH4+-N leaching and residual amounts mainly appeared at 20 cm depth. Inferred from the results of the experiment, the neutral nitrogen treatment in the 0-40 cm soil column is more conducive to the conversion of fertilizer nitrogen to inorganic nitrogen for plant absorption, and reduces the risk of nitrogen leaching after fertilization.

Canada & Vietnam: Argex & Hung Thinh – TiO2 pigment

The objective of this study was to compare grain yield, nitrogen use efficiency (NUE) and stay-green traits in winter barley under low and high nitrogen (N) fertilization treatments. Field trials were conducted during two growing seasons in a southern Pannonian location (Novi Sad, Serbia) with fifteen six-rowed barley cultivars released between 1972 and 2013. The rate of genetic gain in grain yield was higher under high N level, indicating that modern barley cultivars use the applied N fertilizer more efficiently than older cultivars. The improvement in NUE and N uptake efficiency were positively related with year of cultivar release under both fertilization levels, while association between N utilization efficiency and year of cultivar release was significant at high N fertilization. Modern cultivars had higher normalized difference vegetation index (NDVI) values at the anthesis, start and mid senescence. Moreover, time to mid senescence was prolonged in modern cultivars, indicating slower N remobilization during early grain filling period. Values of NDVI at different senescence stages were more related to N uptake efficiency, while timing of senescence stages were in association with N utilization. Close association between NDVI values at different senescence stages and N uptake indicate that application of NDVI sensors could be used for identification of cultivars with improved N productivity.

Rainfall interception by winter rapeseed in Brandenburg (Germany) under various nitrogen fertilization treatments

Oilseed rape (Brassica napus L.) is the major oil crop in Europe and Germany but its hydrological functioning is poorly understood. Studies on the interception processes in oilseed rape have been lacking until the present. The interception of rainfall by oilseed rape is expected to vary in response to substantial changes in canopy structure throughout the cropping cycle and fertilization treatment. To determine evaporation of intercepted water, field measurements of a winter oilseed rape crop were conducted for different stages of development and five treatments of fertilization (0, 60, 120, 180 and 240 kg N/ha). Precipitation (P) and throughfall (TF) were measured hourly, along with vegetation structure measurements of the leaf area index (LAI). A range of 0–21% for the percentage of stemflow (SF) of P was estimated from soil moisture measurements. For the vegetation period from March to June the cumulative P of 112 mm was converted into 49 mm TF (44%). The inferred evaporation of intercepted water (I) was 63 mm (56%). There was a gradual and clear increase in I from 45% to 67%, reflecting the increasing fertilization treatments. Hence, less soil water was available with increasing amounts of fertilization, since the water fraction evaporating from the canopy increases. Plant architecture, LAI and meteorological conditions during the cropping cycle appeared to be the main factors determining I. For irrigation planning and water use, studies of the evaporation of intercepted water must be considered.