scholarly journals Fertilizer Nitrogen Uptake and Partitioning in Young and Mature Common Hackberry (Celtis occidentalis) Trees

2013 ◽  
Vol 39 (2) ◽  
Author(s):  
L.P. Werner ◽  
L.G. Jull

Twenty-one mature and thirty-six young common hackberry (Celtis occidentalis L.) trees received a single application of 15N double isotope enriched ammonium-nitrate (NH4NO3) fertilizer. Application rates were 0, 0.49, and 1.47 kg N 100 m-2 of canopy coverage, respectively. Foliage, current season stem wood, stem wood, root, and fruit tissues were analyzed for total concentration [N] and nitrogen derived from fertilizer (NDFF). Growth phase and application rate did not consistently affect total % [N], particularly the N demanding foliage. Growth phase and application rate significantly affected the percentage of NDFF. In every instance, NDFF was highest in the tissues of young trees and/or trees receiving the 1.47 kg N 100 m-2 application rate. Mature trees relied upon previously assimilated N to meet the annual demand for N to a greater extent than young trees.

Author(s):  
Subin Kalu ◽  
Gboyega Nathaniel Oyekoya ◽  
Per Ambus ◽  
Priit Tammeorg ◽  
Asko Simojoki ◽  
...  

AbstractA 15N tracing pot experiment was conducted using two types of wood-based biochars: a regular biochar and a Kon-Tiki-produced nutrient-enriched biochar, at two application rates (1% and 5% (w/w)), in addition to a fertilizer only and a control treatment. Ryegrass was sown in pots, all of which except controls received 15N-labelled fertilizer as either 15NH4NO3 or NH415NO3. We quantified the effect of biochar application on soil N2O emissions, as well as the fate of fertilizer-derived ammonium (NH4+) and nitrate (NO3−) in terms of their leaching from the soil, uptake into plant biomass, and recovery in the soil. We found that application of biochars reduced soil mineral N leaching and N2O emissions. Similarly, the higher biochar application rate of 5% significantly increased aboveground ryegrass biomass yield. However, no differences in N2O emissions and ryegrass biomass yields were observed between regular and nutrient-enriched biochar treatments, although mineral N leaching tended to be lower in the nutrient-enriched biochar treatment than in the regular biochar treatment. The 15N analysis revealed that biochar application increased the plant uptake of added nitrate, but reduced the plant uptake of added ammonium compared to the fertilizer only treatment. Thus, the uptake of total N derived from added NH4NO3 fertilizer was not affected by the biochar addition, and cannot explain the increase in plant biomass in biochar treatments. Instead, the increased plant biomass at the higher biochar application rate was attributed to the enhanced uptake of N derived from soil. This suggests that the interactions between biochar and native soil organic N may be important determinants of the availability of soil N to plant growth.


Agronomy ◽  
2021 ◽  
Vol 11 (7) ◽  
pp. 1368
Author(s):  
Wenzheng Tang ◽  
Wene Wang ◽  
Dianyu Chen ◽  
Ningbo Cui ◽  
Haosheng Yang ◽  
...  

In order to meet the growing food demand of the global population and maintain sustainable soil fertility, there is an urgent need to optimize fertilizer application amount in agricultural production practices. Most of the existing studies on the optimal K rates for apple orchards were based on case studies and lack information on optimizing K-fertilizer management on a regional scale. Here, we used the method of combining meta-analysis with the K application rate-yield relationship model to quantify and summarize the optimal K rates of the Loess Plateau and Bohai Bay regions in China. We built a dataset based on 159 observations obtained from 18 peer-reviewed literature studies distributed in 15 different research sites and evaluated the regional-scale optimal K rates for apple production. The results showed that the linear plus platform model was more suitable for estimating the regional-scale optimal K rates, which were 208.33 and 176.61 kg K ha−1 for the Loess Plateau and Bohai Bay regions of China, respectively. Compared with high K application rates, the optimal K rates increased K use efficiency by 45.88–68.57%, with almost no yield losses. The optimal K rates also enhanced the yield by 6.30% compared with the low K application rates.


2016 ◽  
Vol 154 (5) ◽  
pp. 812-827 ◽  
Author(s):  
M. J. BELL ◽  
J. M. CLOY ◽  
C. F. E. TOPP ◽  
B. C. BALL ◽  
A. BAGNALL ◽  
...  

SUMMARYIncreasing recognition of the extent to which nitrous oxide (N2O) contributes to climate change has resulted in greater demand to improve quantification of N2O emissions, identify emission sources and suggest mitigation options. Agriculture is by far the largest source and grasslands, occupying c. 0·22 of European agricultural land, are a major land-use within this sector. The application of mineral fertilizers to optimize pasture yields is a major source of N2O and with increasing pressure to increase agricultural productivity, options to quantify and reduce emissions whilst maintaining sufficient grassland for a given intensity of production are required. Identification of the source and extent of emissions will help to improve reporting in national inventories, with the most common approach using the IPCC emission factor (EF) default, where 0·01 of added nitrogen fertilizer is assumed to be emitted directly as N2O. The current experiment aimed to establish the suitability of applying this EF to fertilized Scottish grasslands and to identify variation in the EF depending on the application rate of ammonium nitrate (AN). Mitigation options to reduce N2O emissions were also investigated, including the use of urea fertilizer in place of AN, addition of a nitrification inhibitor dicyandiamide (DCD) and application of AN in smaller, more frequent doses. Nitrous oxide emissions were measured from a cut grassland in south-west Scotland from March 2011 to March 2012. Grass yield was also measured to establish the impact of mitigation options on grass production, along with soil and environmental variables to improve understanding of the controls on N2O emissions. A monotonic increase in annual cumulative N2O emissions was observed with increasing AN application rate. Emission factors ranging from 1·06–1·34% were measured for AN application rates between 80 and 320 kg N/ha, with a mean of 1·19%. A lack of any significant difference between these EFs indicates that use of a uniform EF is suitable over these application rates. The mean EF of 1·19% exceeds the IPCC default 1%, suggesting that use of the default value may underestimate emissions of AN-fertilizer-induced N2O loss from Scottish grasslands. The increase in emissions beyond an application rate of 320 kg N/ha produced an EF of 1·74%, significantly different to that from lower application rates and much greater than the 1% default. An EF of 0·89% for urea fertilizer and 0·59% for urea with DCD suggests that N2O quantification using the IPCC default EF will overestimate emissions for grasslands where these fertilizers are applied. Large rainfall shortly after fertilizer application appears to be the main trigger for N2O emissions, thus applicability of the 1% EF could vary and depend on the weather conditions at the time of fertilizer application.


Author(s):  
Syezlin Hasan ◽  
James C. R. Smart ◽  
Rachel Hay ◽  
Sharyn Rundle-Thiele

Research focused on understanding wider systemic factors driving behavioral change is limited with a dominant focus on the role of individual farmer and psychosocial factors for farming practice change, including reducing fertilizer application in agriculture. Adopting a wider systems perspective, the current study examines change and the role that supporting services have on fertilizer application rate change. A total of 238 sugarcane growers completed surveys reporting on changes in fertilizer application along with factors that may explain behavior change. Logistic regressions and negative binomial count-data regressions were used to examine whether farmers had changed fertilizer application rates and if they had, how long ago they made the change, and to explore the impact of individual and system factors in influencing change. Approximately one in three sugarcane growers surveyed (37%) had changed the method they used to calculate fertilizer application rates for the cane land they owned/managed at some point. Logistic regression results indicated growers were less likely to change the basis for their fertilizer calculation if they regarded maintaining good relationships with other local growers as being extremely important, they had another source of off-farm income, and if they had not attended a government-funded fertilizer management workshop in the five years preceding the survey. Similar drivers promoted early adoption of fertilizer practice change; namely, regarding family traditions and heritage as being unimportant, having sole decision-making authority on farming activities and having attended up to 5 workshops in the five years prior to completing the survey. Results demonstrated the influence of government-funded services to support practice change.


Proceedings ◽  
2020 ◽  
Vol 36 (1) ◽  
pp. 84
Author(s):  
Ziaf ◽  
Haider ◽  
Malik ◽  
Anwar ◽  
Riaz

Onion (Allium cepa L.), locally famous as “Piaz”, occupies a prominent place among commercial crops of Pakistan, by supplementing the income of small/marginal land-hold farmers. One of the major constraints of onion farming in Pakistan is poor nursery due to adoption of traditional planting methods and overfertilization, which ultimately increases cost of production and loss of resources. The current study, comprised of two experiments, was carried out at Vegetable Area, University of Agriculture Faisalabad, to determine the most suitable nursery raising system and fertilizer application rate for onion nursery in order to get maximum plant population of good quality seedlings. The first experiment comprised of four different nursery growing methods: (1) flat bed + broadcast sowing, (2) flat bed + line sowing, (3) raised bed (6 inches height from ground surface) + broadcast sowing, and (4) raised bed + line sowing. The largest plant population, and highest plant fresh and dry weights were obtained on flat beds under line sowing. The smallest plant population was obtained on raised beds under broadcast sowing, however, the lowest fresh and dry weights of seedlings were found with flat beds under broadcast sowing. The second experiment comprised of three diammonium phosphate (DAP) application rates (50 g, 100 g and 150 g per 272.25 ft−2 applied at one-week interval) and a control. The maximum shoot and root lengths as well as fresh and dry weights were obtained with 100 g DAP 272 ft−2. In conclusion, line sowing on flat beds and application of 100g DAP 272 ft−2 at one-week interval produced high quality nursery of onion cv. Phulkara. But, flat bed system must be coupled with proper drainage to avoid excessive water due to frequent rainfall in tropical areas.


1997 ◽  
Vol 128 (4) ◽  
pp. 415-424 ◽  
Author(s):  
C. J. PILBEAM ◽  
A.M. McNEILL ◽  
H. C. HARRIS ◽  
R. S. SWIFT

15N-labelled fertilizer was applied at different rates (0, 30, 60, 90 kg N ha−1) and in different forms (urea or ammonium sulphate) to wheat grown in Syria in three seasons (1991/92, 1992/93 and 1994/95).Recovery of 15N-labelled fertilizer in the above-ground crop at harvest was low (8–22%), with the amount of 15N-labelled fertilizer recovered in the crop increasing as the rate of application increased. Fertilizer application caused a significant increase in the amount of unlabelled soil N in the crop, suggesting that the application of N fertilizer caused a ‘real’ added nitrogen interaction. Recovery of 15N-labelled fertilizer in the crop was unaffected by the form of the fertilizer.On average 31% (14–54%) of the 15N-labelled fertilizer remained in the soil at harvest, mostly in the 0–20 cm layer. At the lowest application rate (30 kg N ha−1) most of the residual fertilizer was as organic N, but at the higher application rates (60 and 90 kg N ha−1), a greater proportion of the 15N-labelled fertilizer was recovered as inorganic N, presumably as the result of top-dressing N in dry conditions in the spring. The amount of 15N-labelled fertilizer remaining in the soil increased as the fertilizer rate increased, but was unaffected by the form of fertilizer applied.Losses of 15N-labelled fertilizer were large (>35%), probably caused by gaseous losses, either through volatilization of N from the calcareous soil, or through denitrification from wet soils rich in organic residues.N fertilization strategies in the West Asia/North Africa (WANA) region should take note of the low recovery of N fertilizer by the crop in the season of application, and the resultant large quantities of residual fertilizer.


HortScience ◽  
1999 ◽  
Vol 34 (3) ◽  
pp. 463D-463
Author(s):  
Kimberly Klock-Moore

The objective of this experiment was to compare the growth of impatiens `Accent Orange' in substrates containing compost made from biosolids and yard trimmings with four slow-release fertilizer application rates. Plugs of impatiens were transplanted into 400-ml pots filled with 100% compost as a stand-alone substrate or with 60%, 30%, or 0% compost combined with control substrate components. Six days after transplanting, all plants were top-dressed with 0.5, 1, 2, or 4 g of Nutricote 13N-5.7P-10.8K (type 180) per pot. Shoot dry mass increased as the percentage of compost in the substrate increased from 0% to 100%. Shoot dry mass also increased as the fertilizer application rate increased from 0.5 to 4 g per pot. Plants grown in 30% and 60% compost with 0.5 g of fertilizer were similar in size to plants grown in 0% compost with 4 g of fertilizer per pot. Plants grown in 100% compost at all of the fertilizer rates were larger than all other plants in this study.


2009 ◽  
Vol 35 (5) ◽  
pp. 252-262
Author(s):  
L.P. Werner ◽  
L.G. Jull

Ammonium-nitrate (NH4NO3) double enriched with the 15N isotope (1.5 atom %) was used to evaluate fertilizer N recovery, N partitioning, and aboveground N status in container-grown common hackberry (Celtis occidentalis L.) trees back-filled with native soil at Arlington, Wisconsin and Lisle, Illinois, U.S. Treatments consisted of 0, 1.42 g N tree-1 (0.05 oz) and 4.27 g N tree-1 (0.15 oz), the area equivalent of 0, 0.49, and 1.47 kg N 100 m-2 (0, 1, and 3 lb N 1000 ft-2). Trees were harvested 14, 30, 60, and 90 days after fertilization. Fertilizer-induced changes in aboveground N status were significant only at the 4.27 g N tree-1 (0.15 oz) treatment level. The amount of fertilizer N recovered in aboveground tissues increased with rate of application. Fertilizer N was preferentially partitioned to foliage and current season stem wood. The percentage of fertilizer recovered in aboveground tissues did not differ between the application rates, ranging from 15%–25% at Arlington, WI, and 5%–9% at Lisle, IL. Frost damage to the foliage at Lisle, IL may have resulted in location differences in aboveground biomass which affected fertilizer N uptake and recovery. These data suggest fertilizer N accumulated in nontarget sinks and/or were lost from the site of application at both rates of application.


2020 ◽  
Vol 66 (No. 9) ◽  
pp. 468-476
Author(s):  
Miroslav Jursík ◽  
Martin Kočárek ◽  
Michaela Kolářová ◽  
Lukáš Tichý

Six sunflower herbicides were tested at two application rates (1N and 2N) on three locations (with different soil types) within three years (2015–2017). Efficacy of the tested herbicides on Chenopodium album increased with an increasing cation exchange capacity (CEC) of the soil. Efficacy of pendimethalin was 95%, flurochloridone and aclonifen 94%, dimethenamid-P 72%, pethoxamid 49% and S-metolachlor 47%. All tested herbicides injured sunflower on sandy soil (Regosol) which had the lowest CEC, especially in wet conditions (phytotoxicity 27% after 1N application rate). The highest phytotoxicity was recorded after the application of dimethenamid-P (19% at 1N and 45% at 2N application rate). Main symptoms of phytotoxicity were leaf deformations and necroses and the damage of growing tips, which led to destruction of some plants. Aclonifen, pethoxamid and S-metolachlor at 1N did not injure sunflower on the soil with the highest CEC (Chernozem) in any of the experimental years. Persistence of tested herbicides was significantly longer in Fluvisol (medium CEC) compared to Regosol and Chernozem. Dimethenamid-P showed the shortest persistence in Regosol and Chernozem. The majority of herbicides was detected in the soil layer 0–5 cm in all tested soils. Vertical transport of herbicides in soil was affected by the herbicide used, soil type and weather conditions. The highest vertical transport was recorded for dimethenamid-P and pethoxamid (4, resp. 6% of applied rate) in Regosol in the growing season with high precipitation.  


2018 ◽  
Vol 40 (3) ◽  
pp. 304-312 ◽  
Author(s):  
Lais Tessari Perboni ◽  
Dirceu Agostinetto ◽  
Leandro Vargas ◽  
Joanei Cechin ◽  
Renan Ricardo Zandoná ◽  
...  

Abstract: The goals of this study were to evaluate herbicide application rates at different timings for preharvest desiccation of wheat (Trial 1), as well as to evaluate the effect of the timing of herbicide desiccation at preharvest and harvest timing (Trial 2) on yield, germination, and herbicide residue in wheat seed. In Trial 1, treatments consisted of two application rates of glufosinate, glyphosate, paraquat, or paraquat+diuron and a control without application; application time periods were in the milk grain to early dough stage, soft dough to hard dough stage, and hard dough stage. In Trial 2, treatments consisted of different application time periods (milk grain to early dough stage, and soft dough to hard dough stage), different herbicides (glufosinate, 2,4-D+glyphosate, and untreated control), and different harvest times (5, 10 and 15 days after herbicide application). One thousand seeds weight, yield, first and final germination count, and herbicide residue on seeds were evaluated. Preharvest desiccation with paraquat, glufosinate, and 2,4-D+glyphosate at the milk grain to early dough stage reduces wheat yield. Regardless of the herbicide and application rate, application in the milk grain to early dough stage and soft dough to hard dough stage provides greater germination of wheat seeds, except at the lower dose of paraquat. Systemic herbicides accumulate more in wheat seeds.


Sign in / Sign up

Export Citation Format

Share Document