Optimum Soluble and Slow-release N Rates for Rhododendrons and the Fate of Such N Applied to Various Potting Media

Two year-long, factorial experiments were conducted on Rhododendron catawbienses (cv. Roseum elegans) grown in 2.3-liter plastic pots. I) Annual N rates of 0, 0.4, 0.8, 1.6, and 3.2 g/pot were applied as NH4NO3 (SBL) or sulfur-coated urea (SR) to plants potted in a composted hardwood bark (CHB)/peatmoss (P)/sand (S) medium. Plant growth and quality was best at 0.8 g N/pot for SBL and 1.6 and 3.2 g N/pot for SR. II) Annual N rates of 0.8 (SBL) and 2.4 (SR) g/pot were chosen as optimum rates and applied to plants potted in the following media: pine bark (PB)/P/S; CHB/P/S; P/S; and PB/CHB/P/S. Plant growth and N uptake was best in PB/PS. Plant quality was best in P/S. NO3 in leachate did not differ among media, but was greater in SBL. Total N immobilized in media was greater in PB/CHB/P/S. N recovered from SR-treated pots as unused fertilizer did not differ among media. Total applied N recovered was 90% for SBL and 51% for SR.

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Triticale out-performs wheat on range of UK soils with a similar nitrogen requirement

The Journal of Agricultural Science ◽

10.1017/s0021859616000356 ◽

2016 ◽

Vol 155 (2) ◽

pp. 261-281 ◽

Cited By ~ 7

Author(s):

S. E. ROQUES ◽

D. R. KINDRED ◽

S. CLARKE

Keyword(s):

Harvest Index ◽

Field Experiments ◽

N Uptake ◽

N Fertilizer ◽

Yield Response ◽

Consistent Difference ◽

Total N ◽

The Mean ◽

The Uk ◽

N Rates

SUMMARYTriticale has a reputation for performing well on poor soils, under drought and with reduced inputs, but there has been little investigation of its performance on the better yielding soils dominated by wheat production. The present paper reports 16 field experiments comparing wheat and triticale yield responses to nitrogen (N) fertilizer on high-yielding soils in the UK in harvest years 2009–2014. Each experiment included at least two wheat and at least two triticale varieties, grown at five or six N fertilizer rates from 0 to at least 260 kg N/ha. Linear plus exponential curves were fitted to describe the yield response to N and to calculate economically optimal N rates. Normal type curves with depletion were used to describe protein responses to N. Whole crop samples from selected treatments were taken prior to harvest to measure crop biomass, harvest index, crop N content and yield components. At commercial N rates, mean triticale yield was higher than the mean wheat yield at 13 out of 16 sites; the mean yield advantage of triticale was 0·53 t/ha in the first cereal position and 1·26 t/ha in the second cereal position. Optimal N requirement varied with variety at ten of the 16 sites, but there was no consistent difference between the optimal N rates of wheat and triticale. Triticale grain had lower protein content and lower specific weight than wheat grain. Triticale typically showed higher biomass and straw yields, lower harvest index and higher total N uptake than wheat. Consequently, triticale had higher N uptake efficiency and higher N use efficiency. Based on this study, current N fertilizer recommendations for triticale in the UK are too low, as are national statistics and expectations of triticale yields. The implications of these findings for arable cropping and cereals markets in the UK and Northern Europe are discussed, and the changes which would need to occur to allow triticale to fulfil a role in achieving sustainable intensification are explored.

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The effect of lignin application on plant growth and soil biological quality

10.5194/egusphere-egu2020-19535 ◽

2020 ◽

Author(s):

Mesfin Gebremikael ◽

Ramon Vandendaele ◽

Marta Alarcon ◽

Ruben Torregrosa ◽

Stefaan De Neve

Keyword(s):

Plant Growth ◽

Soil Quality ◽

Root Biomass ◽

N Uptake ◽

Urban Trees ◽

Simultaneous Increase ◽

High Dose ◽

Total N ◽

Simultaneous Application ◽

Laboratory Conditions

There is a wide variety of agricultural waste co- and by-products that could potentially be valorised in high-value applications. One of such products is lignin, the second most abundant organic biopolymer after cellulose. Because of the large amounts of pruning wastes in the Mediterranean regions, lignin extraction can be one of the possibilities for valorisation and sustainable management of agricultural wastes. Research on the application of lignin, particularly lignosulfonates, is limited to its use as a biostimulant for root growth under controlled laboratory conditions and as a complexing agent in micronutrient foliar fertilizer formulations. Little is known about the impacts of lignin extracted from various feedstock on plant growth and soil quality.&#160;We investigated the potential of lignin as plant biostimulator and soil conditioner in a pot experiment with fresh soil and lignin extracts obtained from three types of pruning wastes (urban trees, fruit and forest trees) using ryegrass as a test plant, under laboratory conditions. Two doses of lignin extracts (equivalent to 5 and 20 kg lignin-C ha-1) were applied to assess whether the effect on plant growth and soil quality depends on the rate of application. Soil and plant parameters were determined seven weeks after the grass was planted at 17 &#176;C and 16 h photoperiod.&#160;&#160;Root biomass significantly increased (62-152%) in treatments with lignin addition, particularly lignin from urban and forest pruning wastes compared to the control. However, the increase in root biomass did not result in a simultaneous increase in shoot biomass or N uptake showing the need to apply additional plant nutrient. The microbial biomass C did not significantly respond to the application of lignin. A significantly higher dehydrogenase enzyme activity was recorded in samples with the high dose of lignin extracted from the urban wastes compared to the lower dose. Urban waste lignin extract contains 15-18 times more total N compared to the lignin extracts from forest and fruit trees, which could explain its significant effect on enzymatic activities and root biomass.&#160;The findings show that differences in feedstock properties may influence the plant growth stimulating activity of the lignin. Further research is needed to improve the plant growth-stimulating effect of lignin, to investigate the simultaneous application of the major plant nutrients and the response of the microbial community to lignin application. &#160;&#160;&#160;

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RELATIVE PERFORMANCE OF BORON, SULPHUR AND ZINC COATINGS ONTO PRILLED UREA FOR INCREASING PRODUCTIVITY AND NITROGEN USE EFFICIENCY IN MAIZE

Experimental Agriculture ◽

10.1017/s0014479717000254 ◽

2017 ◽

Vol 54 (4) ◽

pp. 577-591 ◽

Cited By ~ 1

Author(s):

VIJAY POONIYA ◽

YASHBIR SINGH SHIVAY ◽

MADAN PAL ◽

RADHIKA BANSAL

Keyword(s):

Nitrogen Use Efficiency ◽

Field Experiments ◽

N Uptake ◽

Maize Yield ◽

Nitrogen Use ◽

Total N ◽

Prilled Urea ◽

Zn Uptake ◽

Coated Urea ◽

Use Efficiency

SUMMARYDeficiencies of micro (Zn, B) and secondary (S) nutrients are well-documented in soil as well as in cereal crops, leading to decreased crop yields and low nutritional quality of food. We evaluated the effects of coated urea on maize yield, N and Zn uptake, and input cost relationships. Field experiments were conducted on maize to test boron-coated (BCU), sulphur-coated (SCU) and zinc-coated urea (ZnCU) during 2013 and 2014. On the basis of 2 years’ average data, the highest grain yield was achieved with 0.5% BCU, 5% SCU and 2.5% ZnCU as zinc sulphate hepta hydrate. These treatments increased yields by 5.4, 12.8 and 9.9% over prilled urea (PU), respectively. Application of 0.5% BCU (supplying 1.4 kg B ha−1), 5% SCU (supplying 14.1 kg S ha−1) and 2.5% ZnCU (supplying 7.05 kg Zn ha−1) registered the highest N concentrations and uptake in grain and stover. Total N uptake (grain + stover) was increased by 7.6, 16.7 and 17.1% with BCU, SCU and ZnCU treatments over PU. As compared to PU, Zn concentration in maize grain was significantly higher and total Zn uptake (grain + stover) increased by 32.4% with 2.5% ZnCU. Coated urea materials also enhanced the partial factor productivity (PFPN), agronomic efficiency (AEN), recovery efficiency (REN) and harvest index (HIN) over those of PU. From the economic viewpoint this study suggests that coating of urea with 0.3% boron, 5% sulphur or 2% zinc gives maximum net returns and benefit-cost ratio. Our data indicate that coating of B, Zn and S onto urea increases maize yield, profitability and nitrogen use efficiency in the western Indo-Gangetic plains of India.

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Responses of yield and N use of spring sown crops to N fertilization, with special reference to the use of plant growth regulators

Agricultural and Food Science ◽

10.23986/afsci.5639 ◽

1999 ◽

Vol 8 (4-5) ◽

pp. 423-440 ◽

Cited By ~ 5

Author(s):

L. PIETOLA ◽

R. TANNI ◽

P. ELONEN

Keyword(s):

Plant Growth ◽

Growth Regulators ◽

Spring Wheat ◽

N Uptake ◽

N Fertilization ◽

N Leaching ◽

Soil Mineral N ◽

Soil Mineral ◽

Mineral N ◽

N Rates

The role of plant growth regulators (PGR) in nitrogen (N) fertilization of spring wheat and oats (CCC), fodder barley (etephon/mepiquat) and oilseed rape (etephone) in crop rotation was studied in 19931996 on loamy clay soil. Carry over effect of the N fertilization rates (0180 kg ha-1 ) was evaluated in 1997. N fertilization rate for the best grain/seed yield (120150 kg ha-1 ) was not affected by PGRs. The seed and N yields of oilseed rape were improved most frequently by recommended use of PGR. The yields of oats were increased in 199596. Even though PGR effectively shortened the plant height of spring wheat, the grain yield increased only in 1995. N yield of wheat grains was not increased. Response of fodder barley to PGR was insignificant or even negative in 1995. The data suggest that PGRs may decrease some N leaching at high N rates by improving N uptake by grain/seeds, if the yield is improved. The carryover study showed that in soils with no N fertilization, as well as in soils of high N rates, N uptake was higher than in soils with moderate N fertilization (6090 kg ha-1 ), independent of PGRs. According to soil mineral N contents, N leaching risk is significant (1535 kg ha-1 ) only after dry and warm late seasons. After a favourable season of high yields, the N rates did not significantly affect soil mineral N contents. ;

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An Entomogenous Nematode Steinernema carpocapsae is Compatible with Potting Media Environments Created by Horticultural Practices

Journal of Entomological Science ◽

10.18474/0749-8004-26.4.390 ◽

1991 ◽

Vol 26 (4) ◽

pp. 390-394 ◽

Cited By ~ 5

Author(s):

Ronald D. Oetting ◽

Joyce G. Latimer

Keyword(s):

Plant Growth ◽

Plant Growth Regulators ◽

Growth Regulators ◽

Galleria Mellonella ◽

Steinernema Carpocapsae ◽

Pine Bark ◽

Peat Moss ◽

Negative Effects ◽

Significant Difference ◽

Potting Media

Three experiments were conducted to evaluate the effect of different potting media and horticultural practices on the infectivity of Steinernema carpocapsae (Weiser). Bioassays were conducted with S. carpocapsae added to potting media containing Galleria mellonella (L.) larvae. Potting media tested were aged pine bark, new pine bark, peat moss, aged cow manure, and a peat/vermiculite soilless medium (Pro-Gro 200). The horticultural practices tested were potting media pH level, fertilization, salt level, and application of plant growth regulators. The plant growth regulators ancymidol, paclobutrazol, chlormequat, and daminozide were each applied as a medium drench. The LC50s of the nematodes against G. mellonella, in potting media with different horticultural practices, were all between 0.50 and 2.06 with no significant difference in infectivity. Nematodes could be used for insect control with no negative effects under these growing conditions.

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Foliar and topdressing application of nitrogen to the common bean crop

Pesquisa Agropecuária Brasileira ◽

10.1590/s0100-204x2018001200005 ◽

2018 ◽

Vol 53 (12) ◽

pp. 1329-1337 ◽

Cited By ~ 1

Author(s):

Tailene Elisa Kotz-Gurgacz ◽

Rogério Peres Soratto ◽

Fernando Vieira Costa Guidorizzi

Keyword(s):

Grain Yield ◽

Common Bean ◽

Slow Release ◽

Urea Formaldehyde ◽

N Uptake ◽

N Application ◽

N Sources ◽

The Common ◽

Slow Release Urea ◽

N Rates

Abstract: The objective of this work was to evaluate the effect of applying N sources to leaves and N rates to the soil on the growth, N uptake, and grain and crude protein yields of the common bean (Phaseolus vulgaris) crop. Three experiments - two irrigated and one rainfed - were conducted during the 2012/2013 agricultural season, in a randomized complete block design with four replicates. The treatments consisted of the application of: four N rates (0, 45, 90, and 180 kg ha-1) to the soil, as topdressing in the V4 stage; and five N sources/rates - i.e., control, without foliar N application; 2.5 kg ha-1 N as conventional urea (N-CU); 5.0 kg ha-1 N-CU; 2.5 kg ha-1 N as slow-release urea-formaldehyde (N-SR); and 5.0 kg ha-1 N-SR - to leaves, in the R5 stage. Soil N fertilization, using rates between 124 and 180 kg ha-1, increases shoot N content and uptake, number of pods per plant, grain yield, and protein content and yield. Regardless of the growing environment and N application to the soil, the foliar supply of N as slow-release urea-formaldehyde increases grain and protein yields, whereas the greatest rate of N as conventional urea also increases grain yield.

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Influence of Slow-release Fertilizer Source on Growth and Quality of Areca Palm, Chrysalidocarpus lutescens Wendl

Journal of Environmental Horticulture ◽

10.24266/0738-2898-6.1.7 ◽

1988 ◽

Vol 6 (1) ◽

pp. 7-9

Author(s):

F. D. Rauch ◽

P. Yahata ◽

P. K. Murakami

Keyword(s):

Plant Growth ◽

Slow Release ◽

Urea Formaldehyde ◽

Slow Release Fertilizer ◽

Slow Release Fertilizers ◽

Coated Urea ◽

Slow Growing ◽

Growing Crop

There was little difference noted in plant growth and quality of Areca palm, Chrysalidocarpus lutescens Wendl., when treated with three levels of several slow-release fertilizers at the manufacturer's recommended rates. The two resin-coated (RC) materials 18N-2.6P-10K and 17N-3.1P-10K (18-6-12 and 17-7-12) and urea formaldehyde (UF) fertilizer 10N-4.4P-8.3K (10-10-10) resulted in significantly better growth than either the isobutyledene diurea (IBDU) 20N-2.2P-4.2K (20-5-5) or the sulfur-coated urea (SCU) 14N-6P-12K (14-14-14) fertilizer sources. The RC materials were the least expensive fertilizers used in the production of this slow growing crop.

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A COMPARISON OF 12- TO 14- MONTH SLOW RELEASE FERTILIZERS IN AZALEA PRODUCTION

HortScience ◽

10.21273/hortsci.26.5.485a ◽

1991 ◽

Vol 26 (5) ◽

pp. 485a-485

Author(s):

Joseph Eakes ◽

John W. Olive

Keyword(s):

Electrical Conductivity ◽

Plant Growth ◽

Slow Release ◽

Fertilizer Application ◽

Pine Bark ◽

Peat Moss ◽

Growth Indices ◽

Potting Medium ◽

Slow Release Fertilizers ◽

First 90 Days

Five 12- to 14- month slow release fertilizers (Osmocote 17-7-12, Sierra 16-6-10, High-N 24-4-7, Sierrablend 17-7-10, and Nutricote 16-10-10 Type 360) were incorporated into a 3:1 pine bark: peat moss potting medium at one of 4 rates (0.9, 1.2, 1.5, and 1.8 kg N/m3). Plant growth of 3 azale a species, `Coral Bells' (Kurume), `Formosa' (Southern Indica), and `Pink Gumpo' (Satsuki), and monthly medium solution electrical conductivity (EC) were determined. Growth indices 180 days after applying fertilizer were greatest for plants receiving the Sierrablend and Osmocote fertilizers regardless of azalea species. Plant growth indices increased as N rate increased for the 3 azaleas, regardless of the fertilizer product. The highest media solution EC readings occurred during the first 90 days after fertilizer application for all fertilizer treatments and declined thereafter.

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Foliar and root uptake of N deriving from simulated atmospheric N depositions in potted apple (Malus domestica) trees

Italus Hortus ◽

10.26353/j.itahort/2021.3.1324 ◽

2021 ◽

Vol 28 (3) ◽

pp. 13-24

Author(s):

Damiano Zanotelli ◽

Massimo Tagliavini ◽

Marta Petrillo ◽

Carlo Andreotti

Keyword(s):

Apple Tree ◽

Foliar Application ◽

N Uptake ◽

Global Scale ◽

Past Century ◽

N Availability ◽

Total N ◽

15N Labelling ◽

Atmospheric Depositions ◽

N Rates

A significant human-driven increment of the available reactive nitrogen (Nr) forms has occurred during the past century at the global scale, which in turn has increased the amount of Nr deposition. Grafted apple trees (Gala / M.9 strain T337) were used in a pot experiment conducted in semicontrolled conditions, where the 15N-labelling technique allowed to trace the fate of N from ammonium nitrate (15NH4 15NO3, isotopic enrichment: 10.3 atoms %) distributed at three increasing rates (N1, N2, N4, where N2 is the double of N1 and N4 is the double of N2) either to soil or to canopy (foliar application) to simulate atmospheric N depositions. At the end of the experiment, plants were destructively sampled, and N derived from depositions (Ndfd), total N, and biomass of above and belowground organs were determined. Uptake rates ranged from 21% to 57% and the Ndfd recovery was higher for soil than for foliar application. Foliar-supplied plants showed a higher Ndfd in leaves and shoots than soil-supplied ones, while the latter showed a higher Ndfd in roots than the former. Moreover, total N in trunk, shoot axes and leaves increased with the N rates up to the level N2, with no further increase in N4. Increasing tree N availability, regardless the supply mode, increased the shoot:root N content. The fact that the N uptake rate was rather stable at increasing N rates suggests that if N from atmospheric depositions becomes increasingly available at the canopy or soil level, it will actively contribute to apple tree nutrition and account for a significant fraction of the apple tree N needs.

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Nitrogen and Water Rates for Subsurface Trickle-irrigated Romaine Lettuce

HortScience ◽

10.21273/hortsci.30.6.1233 ◽

1995 ◽

Vol 30 (6) ◽

pp. 1233-1237 ◽

Cited By ~ 12

Author(s):

Thomas L. Thompson ◽

Thomas A. Doerge

Keyword(s):

Field Experiments ◽

N Uptake ◽

Fertilizer N ◽

Romaine Lettuce ◽

Total N ◽

Soil Water Tension ◽

Water Rates ◽

Yield Quality ◽

Quality Response ◽

N Rates

Two field experiments were conducted with subsurface trickle-irrigated romaine lettuce (Lactuca sativa L. cv. Parris Island Cos) during the 1990–92 winter growing seasons in southern Arizona. The objectives were to determine 1) yield and quality response to varying combinations of soil water tension (SWT) and N fertilizer, 2) seasonal patterns of N uptake, and 3) unutilized fertilizer N. During 1990–91, N rates were 35, 120, and 205 kg·ha–1. During 1991–92, the experiment was factorial with N levels from 50 to 300 kg·ha–1 and target SWT levels of 7.0 and 4.0 kPa. Unutilized fertilizer N was the difference between fertilized and nonfertilized plots in total N inputs not harvested in the crop. When excessive irrigation was not applied (SWT between 6.5 and 7.4 kPa), 95% of the maximum crop yield and yield quality (head length and fresh mass) response occurred at N rates of 156 to 193 kg·ha–1, with unutilized fertilizer N <60 kg·ha–1. Excessive irrigation (4.6 kPa) resulted in lower yields and yield quality and higher unutilized fertilizer N. Romaine accumulated >74% of its total N uptake in the 38 days before harvest. Unutilized fertilizer N increased sharply when adequate N and water rates were exceeded. These results suggest that a target SWT of no wetter than 6.5 kPa is appropriate for subsurface trickle-irrigated romaine lettuce.

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