Growth and Nitrogen Status of Young Pecan Trees Using Fertigation

The prolonged period from tree planting to first commercial harvest of pecan [Carya illinoinensis (Wangenh.) K. Koch] provides incentive for many growers to intensively manage young trees to induce commercial production as soon as possible. This management includes high nitrogen (N) application rates with or without fertigation. However, there remains little data regarding the effect of N fertilization or fertigation on young pecan trees grown under southeastern U.S. orchard conditions. The objectives of this study were to compare the effects of fertigation with more commonly recommended forms of fertilization on growth and leaf N, phosphorous (P), potassium (K), and zinc (Zn) concentrations of first- through third-leaf pecan trees irrigated with microsprinklers. An optimal growth rate of young pecan trees was obtained as easily with a balanced granular fertilizer application using significantly less N compared with fertigation applications. The minimal treatment differences observed along with the fact that leaf N concentration never fell below the minimum recommended level in any treatment throughout the study supports the supposition that first-year pecan trees require no N fertilizer during the year of establishment. Only modest N application rates are required during the second and third growing seasons. This practice helps to promote optimal tree growth while minimizing excessive losses of N to the environment.

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Effect of Differential Rates of Nitrogen Fertilization on Subsequent Recovery of Isotopically Labeled Fertilizer Nitrogen by Mature Almond Trees

HortScience ◽

10.21273/hortsci.30.4.755f ◽

1995 ◽

Vol 30 (4) ◽

pp. 755F-755

Author(s):

Steven A. Weinbaum ◽

Wesley P. Asai ◽

David A. Goldhamer ◽

Franz J.A. Niederholzer ◽

Tom T. Muraoka

Keyword(s):

Fertilizer Application ◽

N Fertilization ◽

Fertilizer N ◽

N Application ◽

Fertilizer Nitrogen ◽

Application Rates ◽

Legitimate Concern ◽

Almond Trees ◽

Leaf N Concentration ◽

Leaf N

There is legitimate concern that excessive fertilizer nitrogen (N) application rates adversely affect groundwater quality in the San Joaquin Valley of California. A 5-year study was conducted to assess the interrelationships between N fertilization rates, tree productivity, leaf [N], soil [NO–3], tree recovery of isotopically labeled fertilizer N, and NO–3 leaching. High N trees recovered <50% as much labeled fertilizer N in the crop as did trees previously receiving low to moderate fertilizer application rates. Our data suggest that the dilution of labeled N in the soil by high residual levels of NO–3 in the soil had a greater effect than tree N status (as expressed by leaf N concentration) on the relative recovery of fertilizer N.

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Nitrogen Management Based on Visible/Near Infrared Spectroscopy in Pear Orchards

Remote Sensing ◽

10.3390/rs13050927 ◽

2021 ◽

Vol 13 (5) ◽

pp. 927

Author(s):

Jie Wang ◽

Xiaojun Shi ◽

Yangchun Xu ◽

Caixia Dong

Keyword(s):

Infrared Spectroscopy ◽

Near Infrared Spectroscopy ◽

Near Infrared ◽

Fertilizer Application ◽

First Year ◽

N Application ◽

N Concentration ◽

Application Rates ◽

Leaf N Concentration ◽

Leaf N

The timely estimation of nitrogen (N) requirements is essential for managing N fertilizer application in pear orchards. Visible/near infrared spectroscopy is a non-destructive and effective technique for real-time assessment of leaf N concentration, but its utility for decisions about fertilizer application in the pear orchards remains to be determined. In this study, we used leaf spectroscopy to determine leaf N concentration, used this value to calculate the amounts of N required for supplementary fertilization, and then evaluated the effects of the application. Over the two-year study, Cuiguan pear trees were treated with N at the following rates: 0 (N0), 100 (N1), 200 (N2), 300 (N3), and 400 (N4) g N per tree, regarded as five “controlled” N application rates. Another four “regulatory” treatments (Nr1-4) were fertilized as the “controlled” N application rates the first year, then given adjusted N application by topdressing as calculated using the N concentrations inferred from visible/near infrared spectroscopy data the second year. A model (R2 = 0.82) was established the first year to relate leaf spectra and N concentration using a partial least squares regression with full bands (350–2500 nm). The amount of N in the topdressing for the supplemental treatments was determined using the predicted leaf N concentration and the topdressing calculation method adapted from the N balance formula. Results showed that adjusted N applications of the Nr1 and Nr2 increased yield by 26% and 23%, respectively, over the controlled treatments N1 and N2. Although treatments Nr3 and Nr4 did not increase yield significantly over N3 and N4, the partial factor productivity of nitrogen in Nr4 was higher than the N4. The transverse diameter of fruit from Nr1 trees was significantly higher than from N1 trees, while the longitudinal diameter of fruit from Nr1, Nr2, and Nr3 trees was significantly higher than from N1, N2 and N3 trees, suggesting that fruit longitudinal growth and single-fruit weight is stimulated by adjusted N applications. However, the soluble solids in fruit from trees receiving adjusted N were not significantly greater than in fruit from non-supplemented trees. In conclusion, our results illustrate that regulatory N management contributes to fruit yield and quality especially in the nitrogen deficiency condition and improves the nitrogen use efficiency in nitrogen surplus. The N prediction model established using the nondestructive visible/near infrared spectroscopy is convenient and economical.

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Optimizing Nitrogen Application for Growth and Productivity of Pomegranates

Agronomy ◽

10.3390/agronomy10030366 ◽

2020 ◽

Vol 10 (3) ◽

pp. 366

Author(s):

Silit Lazare ◽

Yang Lyu ◽

Uri Yermiyahu ◽

Yehuda Heler ◽

Alon Ben-Gal ◽

...

Keyword(s):

N Uptake ◽

N Fertilization ◽

Field Conditions ◽

Nitrogen Application ◽

N Application ◽

Environmentally Responsible ◽

Irrigation Solution ◽

Vegetative Indices ◽

Leaf N ◽

Usage Efficiency

Quantification of actual plant consumption of nitrogen (N) is necessary to optimize fertilization efficiency and minimize contamination of earth resources. We examined the performance of fruit-bearing pomegranate trees grown in soilless media and exposed to eight N-fertigation treatments, from 5 to 200 mg N L−1. Reproductive and vegetative indices were found to be optimal when 20 to 70 mg N L−1 was supplied. Nitrogen application levels over 70 mg L−1 reduced pomegranate development and reproduction. N uptake in low-level treatments was almost 100% and decreased gradually, down to 13% in 200 mg N L−1 treatment. N usage efficiency was maximized under 20 mg N L−1, in which case 80% to 90% of added N was taken up by the trees. At high N application, its efficiency was reduced with less than 50% utilized by the trees. Leaf N increased to a plateau as a function of increasing irrigation solution N, maximizing at ~15 to 20 mg N g−1. Therefore, analysis of diagnostic leaves is not a valid method to identify excessive detrimental N. The results should be valuable in the development of efficient, sustainable, environmentally responsible protocols for N fertilization in commercial pomegranate orchards, following adaptation and validation to real soil field conditions.

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Suitability of peanut residue as a nitrogen source for a rye cover crop

Scientia Agricola ◽

10.1590/s0103-90162007000200012 ◽

2007 ◽

Vol 64 (2) ◽

pp. 181-186 ◽

Cited By ~ 9

Author(s):

Kipling Shane Balkcom ◽

Charles Wesley Wood ◽

James Fredrick Adams ◽

Bernard Meso

Keyword(s):

Cover Crops ◽

Cover Crop ◽

Sandy Loam ◽

Soil Surface ◽

N Application ◽

Growing Seasons ◽

Application Rates ◽

Arachis Hypogaea L ◽

Secale Cereale L ◽

Biomass Yields

Leguminous winter cover crops have been utilized in conservation systems to partially meet nitrogen (N) requirements of succeeding summer cash crops, but the potential of summer legumes to reduce N requirements of a winter annual grass, used as a cover crop, has not been extensively examined. This study assessed the N contribution of peanut (Arachis hypogaea L.) residues to a subsequent rye (Secale cereale L.) cover crop grown in a conservation system on a Dothan sandy loam (fine-loamy, kaolinitic, thermic Plinthic Kandiudults) at Headland, AL USA during the 2003-2005 growing seasons. Treatments were arranged in a split plot design, with main plots of peanut residue retained or removed from the soil surface, and subplots as N application rates (0, 34, 67 and 101 kg ha-1) applied in the fall. Peanut residue had minimal to no effect on rye biomass yields, N content, carbon (C) /N ratio, or N, P, K, Ca and Zn uptake. Additional N increased rye biomass yield, and N, P, K, Ca, and Zn uptakes. Peanut residue does not contribute significant amounts of N to a rye cover crop grown as part of a conservation system, but retaining peanut residue on the soil surface could protect the soil from erosion early in the fall and winter before a rye cover crop grows sufficiently to protect the typically degraded southeastern USA soils.

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Influence of intra-row plant spacing, phosphorus application and growth stage on the forage, seed yields and quality of phasey bean (Macroptilium lathyroides) in subhumid area of Nigeria

Nigerian Journal of Animal Production ◽

10.51791/njap.v31i1.1456 ◽

2021 ◽

Vol 31 (1) ◽

pp. 45-50

Author(s):

A. T. Omokanye ◽

J. T. Amodu ◽

S. O. Onifade

Keyword(s):

Production Systems ◽

Fertilizer Application ◽

Plant Spacing ◽

Growing Seasons ◽

Application Rates ◽

P Fertilizer ◽

P Application ◽

Macroptilium Lathyroides ◽

Seed Yields ◽

Phosphorus Application

Forage, seed yields and herbage chemical composition of phasey bean Macroptilium lathyroides) were investigated at 3 intra-row plant spacings (15, 30 and 45cm between plants; 50 cm between roms), 4 phosphorus (P) fertilizer application rates (O), 50, 100 and 750 kg/ha P) and 5 harvest stages (uncut control, 6, 9, 12 and 15 weeks post sowing) in two growing seasons at Shika in northern Nigeria. The least intra-row plant spacing (15cm) produced higher (p<0.01) total DM vield (1.50 t/ha) than wider spacings. The proportion of leaf was least (40 %) in the widest spacing compared with other spacings (59-62 %). The P-fertilized plots produced 58-60% more total DM vields than the unfertilized plots and total DM yields increased with advanced plant growth. The highest percentage (61-63) of leaf was recorded from 6 to 12 weeks post sowing. Nitrogen level in herbage increased (p<0.05) with increased intra-row plant spacing and P application. Phosphorus and Calcium. Levels in herbage did not respond to intra-row plant spacing but increased with P application. The Ca:P ratios at the harvest stages were between 1:1 and 6:1. The highest seed yields (198 and 188 kg/ha) were recorded respectiely in the least intra-row plant spacing and the application of 100 kg Piha. Supplementation of calves on grasses/cereal stovers with phasey bean hay in a sustainable crop livestock production systems is suggested.

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Inoculation and N Fertilization Affect the Dry Matter, N Fixation, and Bioactive Compounds in Sulla Leaves

Agronomy ◽

10.3390/agronomy9060289 ◽

2019 ◽

Vol 9 (6) ◽

pp. 289 ◽

Cited By ~ 1

Author(s):

Leonardo Sulas ◽

Giuseppe Campesi ◽

Giovanna Piluzza ◽

Giovanni A. Re ◽

Paola A. Deligios ◽

...

Keyword(s):

Bioactive Compounds ◽

Dry Matter ◽

Seed Set ◽

Natural Habitat ◽

N Fertilization ◽

N Fixation ◽

N Application ◽

Uninoculated Control ◽

The Relationship ◽

Leaf N

Sulla (Sulla coronaria [L.] Medik), a Mediterranean short-lived legume with tolerance to drought-prone environments, requires inoculation outside its natural habitat. Its leaves are appreciated for the bromatological composition and content of bioactive compounds. However, no information is available regarding the distinct effects of inoculation and nitrogen (N) applications on leaf dry matter (DM), fixed N, and bioactive compounds. Sulla leaves were sampled from the vegetative stage to seed set in Sardinia (Italy) during 2013–2014 and leaf DM, N content, and fixed N were determined. Compared to the best performing inoculated treatments, DM yield and fixed N values of the control only represented 8% to 20% and 2% to 9%, respectively. A significant relationship between fixed N and leaf DM yield was established, reaching 30 kg fixed N t–1 at seed set. Significant variations in leaf atom% 15N excess and %Ndfa quantified decreases in leaf N fixation coupled with N application. Moreover, the petiole content of phenolic compounds markedly increased in the uninoculated control, suggesting deeper investigations on the relationship between bioactive compounds and inoculation treatments. Results highlighted substantial variation in DM, N yields, N-fixation ability, and content of bioactive compounds of sulla leaves caused by inoculation and N fertilization.

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Response of two-row and six-row barley to fertiliser N under Irish conditions

Irish Journal of Agricultural and Food Research ◽

10.1515/ijafr-2016-0013 ◽

2016 ◽

Vol 55 (2) ◽

pp. 136-144 ◽

Cited By ~ 1

Author(s):

R. Hackett

Keyword(s):

Winter Barley ◽

N Use Efficiency ◽

Soil N ◽

N Application ◽

Growing Seasons ◽

Application Rates ◽

Different Types ◽

Use Efficiency ◽

Hybrid Cultivar ◽

N Use

Abstract A range of cultivar types, including two-row and six-row types as well as line and hybrid types, are used for winter barley production in Ireland. There is little information available on the fertiliser nitrogen (N) requirements or the N use efficiency of these different types, particularly under Irish conditions. The objectives of the work presented here were to compare the response to fertiliser N of a two-row line cultivar, a six-row line cultivar and a six-row hybrid cultivar in terms of grain yield and aspects of N use efficiency. Experiments were carried out over three growing seasons, in the period 2012-2014, on a light-textured soil comparing the response of the three cultivars of winter barley to fertiliser N application rates ranging from 0 to 260 kg N/ha. There was no evidence that cultivar type, regardless of whether it was a two-row or six-row line cultivar or a six-row hybrid cultivar, influenced the response to fertiliser N of winter barley. There were some indications that six-row cultivars were less efficient at recovering soil N but used accumulated N more efficiently than the two-row cultivar. This work provided no evidence to support adjustment of fertiliser N inputs to winter barley based on cultivar type.

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Carbon footprint of crop production in China: an analysis of National Statistics data

The Journal of Agricultural Science ◽

10.1017/s0021859614000665 ◽

2014 ◽

Vol 153 (3) ◽

pp. 422-431 ◽

Cited By ~ 48

Author(s):

K. CHENG ◽

M. YAN ◽

D. NAYAK ◽

G. X. PAN ◽

P. SMITH ◽

...

Keyword(s):

Carbon Footprint ◽

Crop Production ◽

Management Practices ◽

Fertilizer Application ◽

N Fertilization ◽

Paddy Rice ◽

N Fertilizer ◽

Carbon Equivalent ◽

Ghg Mitigation ◽

Application Rates

SUMMARYAssessing carbon footprint (CF) of crop production in a whole crop life-cycle could provide insights into the contribution of crop production to climate change and help to identify possible greenhouse gas (GHG) mitigation options. In the current study, data for the major crops of China were collected from the national statistical archive on cultivation area, yield, application rates of fertilizer, pesticide, diesel, plastic film, irrigated water, etc. The CF of direct and indirect carbon emissions associated with or caused by these agricultural inputs was quantified with published emission factors. In general, paddy rice, wheat, maize and soybean of China had mean CFs of 2472, 794, 781 and 222 kg carbon equivalent (CE)/ha, and 0·37, 0·14, 0·12 and 0·10 kg CE/kg product, respectively. For dry crops (i.e. those grown without flooding the fields: wheat, maize and soybean), 0·78 of the total CFs was contributed by nitrogen (N) fertilizer use, including both direct soil nitrous oxide (N2O) emission and indirect emissions from N fertilizer manufacture. Meanwhile, direct methane (CH4) emissions contributed 0·69 on average to the total CFs of flooded paddy rice. Moreover, the difference in N fertilizer application rates explained 0·86–0·93 of the provincial variations of dry crop CFs while that in CH4 emissions could explain 0·85 of the provincial variation of paddy rice CFs. When a 30% reduction in N fertilization was considered, a potential reduction in GHGs of 60 megatonne (Mt) carbon dioxide equivalent from production of these crops was projected. The current work highlights opportunities to gain GHG emission reduction in production of crops associated with good management practices in China.

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Effects of Fertilization on the Growth and Quality of Container-grown Areca Palm and Chinese Hibiscus during Establishment in the Landscape

HortTechnology ◽

10.21273/horttech.20.2.389 ◽

2010 ◽

Vol 20 (2) ◽

pp. 389-394

Author(s):

Timothy K. Broschat ◽

Kimberly Anne Moore

Keyword(s):

Ornamental Plants ◽

Plant Size ◽

N Fertilization ◽

N Application ◽

Landscape Plants ◽

Application Rates ◽

Affected Plant ◽

Highly Correlated ◽

Chinese Hibiscus

The roots of container-grown ornamental plants primarily are concentrated within the original container substrate root ball during the establishment period following transplanting into the landscape. Plants growing in container substrates containing pine bark or peatmoss have higher nitrogen (N) requirements than in most landscape soils due to microbial immobilization of N by these organic components. However, use of high-N fertilizers, such as those used in container production of ornamentals, can cause imbalances with potassium (K) and magnesium (Mg) when used on palms in sandy landscape soils. Areca palm (Dypsis lutescens) and chinese hibiscus (Hibiscus rosa-sinensis ‘President’) that had been growing in containers were transplanted into a landscape soil to determine if high N fertilization during the establishment period could accelerate the rate of establishment without exacerbating K and Mg deficiencies. Although plants of both species had the darkest green color and largest size when continuously fertilized with high N fertilizer, this treatment did induce Mg deficiency in both species. Plant size and color for both species were highly correlated with cumulative N application rates, but also with initial N application rates, suggesting that high N fertilization during the first 6 months affected plant quality at 12 and 24 months after planting, even if high N fertilization was discontinued. However, continued use of a moderate N landscape palm maintenance fertilizer ultimately produced areca palm plants as good as those receiving high N during the establishment period.

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Nitrogen Uptake Efficiency and Leaching Losses from Lysimeter-grown Citrus Trees Fertilized at Three Nitrogen Rates

Journal of the American Society for Horticultural Science ◽

10.21273/jashs.121.1.57 ◽

1996 ◽

Vol 121 (1) ◽

pp. 57-62 ◽

Cited By ~ 23

Author(s):

J.P. Syvertsen ◽

M.L. Smith

Keyword(s):

N Uptake ◽

Dry Weight ◽

Fruit Yield ◽

Fibrous Root ◽

N Application ◽

Nitrogen Uptake Efficiency ◽

Uptake Efficiency ◽

N Concentration ◽

Application Rates ◽

Leaf N

Four-year-old `Redblush' grapefruit (Citrus paradisi Macf.) trees on either the relatively fast-growing rootstock `Volkamer' lemon (VL) (C. volkameriana Ten. & Pasq.) or on the slower-growing rootstock sour orange (SO) (C. aurantium L.) were transplanted into 7.9-m3 drainage lysimeter tanks filled with native Candler sand, irrigated similarly, and fertilized at three N rates during 2.5 years. After 6 months, effects of N application rate and rootstock on tree growth, evapotranspiration, fruit yield, N uptake, and leaching were measured during the following 2 years. When trees were 5 years old, low, medium, and high N application rates averaged about 79,180, or 543 g N/tree per year and about 126,455, or 868 g N/tree during the following year. Recommended rates average about 558 g N/tree per year. A lysimeter tank with no tree and additional trees growing outside lysimeters received the medium N treatment. Nitrogen concentration in the drainage water increased with N rate and exceeded 10 mg·liter-1 for trees receiving the high rates and also for the no tree tank. Leachate N concentration and total N recovered was greater from trees on SO than from those on VL. Average N uptake efficiency of medium N rate trees on VL was 6870 of the applied N and 61 % for trees on SO. Nitrogen uptake efficiency decreased with increased N application rates. Trees outside lysimeters had lower leaf N and fruit yield than lysimeter trees. Overall, canopy volume and leaf N concentration increased with N rate, but there was no effect of N rate on fibrous root dry weight. Fruit yield of trees on SO was not affected by N rate but higher N resulted in greater yield for trees on VL. Rootstock had no effect on leaf N concentration, but trees on VI. developed larger canopies, had greater fibrous root dry weight, used more water, and yielded more fruit than trees on SO. Based on growth, fruit yield and N leaching losses, currently recommended N rates were appropriate for trees on the more vigorous VL rootstock but were 22% to 69 % too high for trees on SO.

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