scholarly journals FOLIAR NITROGEN EFFECTS ON ONION PRODUCTION AND DAMAGE BY THRIPS AND PURPLE BLOTCH

HortScience ◽  
1990 ◽  
Vol 25 (8) ◽  
pp. 864a-864 ◽  
Author(s):  
Robert Wiedenfeld ◽  
B. Scully ◽  
Marvin Miller ◽  
Jonathan Edelson ◽  
Jiandong Wang
Keyword(s):  
N Uptake ◽  
Leaf Age ◽  
Leaf Tissue ◽  
South Texas ◽  
Thrips Tabaci ◽  
Total N ◽  
Foliar Fertilization ◽  
Nitrogen Concentrations ◽  
Use Efficiency ◽  
Leaf N

Purple blotch (Alternari a porri) and thrips (Thrips tabaci) can seriously reduce yields of short day onions in South Texas. The level of injury caused by these organisms is influenced by the concentration of nitrogen in leaf tissue. Lower levels of tissue nitrogen increase susceptibility to A. porri but decrease susceptibility to thrips. The purpose of this study was to evaluate the effect of tissue N levels on joint susceptibility of 4 onion cultivars to A. porri and thrips. Foliage was fertilized at 0, 4, 8, 12 or 16 lbs N/ac/wk for 6 weeks. Nitrogen concentrations in onion leaves varied over time and by leaf age, but showed very little effect due to foliar fertilization. Significant differences in thrips were noted among cultivars, but not among leaf N concentrations with cultivars. Purple blotch outbreak occurred late in the growing season and was not related to leaf N levels. Total N uptake failed to respond to foliar fertilization, therefore overall use efficiency of the foliar N applied averaged only about 10% relative to the amount taken up in the check plots.

Impact of industrial-age climate change on the relationship between water uptake and tissue nitrogen in eucalypt seedlings

2013 ◽  
Vol 40 (2) ◽  
pp. 201 ◽  
Author(s):  
Gyro L. Sherwin ◽  
Laurel George ◽  
Kamali Kannangara ◽  
David T. Tissue ◽  
Oula Ghannoum
Keyword(s):  
High Temperature ◽  
Elevated Co2 ◽  
Water Use ◽  
N Uptake ◽  
15N Nmr ◽  
Plant Water ◽  
Total N ◽  
Use Efficiency ◽  
Chemical Groups ◽  
Tissue Nitrogen

This study explored reductions in tissue nitrogen concentration ([N]) at elevated CO2 concentrations ([CO2]), and changes in plant water and N uptake. Eucalyptus saligna Sm. seedlings were grown under three [CO2] levels (preindustrial (280 μL L–1), current (400 μL L–1) or projected (640 μL L–1)) and two air temperatures (current, (current + 4°C)). Gravimetric water use, leaf gas exchange and tissue dry mass and %N were determined. Solid-state 15N-NMR spectroscopy was used for determining the partitioning of N chemical groups in the dry matter fractions. Water use efficiency (WUE) improved with increasing [CO2] at ambient temperature, but strong leaf area and weak reductions in transpiration rates led to greater water use at elevated [CO2]. High temperature increased plant water use, such that WUE was not significantly stimulated by increasing [CO2] at high temperature. Total N uptake increased with increasing [CO2] but not temperature, less than the increase recorded for plant biomass. Tissue [N] decreased with rising [CO2] and at high temperature, but N use efficiency increased with rising [CO2]. Total N uptake was positively correlated with total water use and root biomass under all treatments. Growth [CO2] and temperature did not affect the partitioning of 15N among the N chemical groups. The reductions of tissue [N] with [CO2] and temperature were generic, not specific to particular N compounds. The results suggest that reductions in tissue [N] are caused by changes in root N uptake by mass flow due to altered transpiration rates at elevated [CO2] and temperature.

Nitrogen use efficiency, economic return and yield performance of Pigeonpea [Cajanus cajan (L.) Millsp.] as influenced by nipping and fertility levels

2019 ◽  
Author(s):  
A.K. Dhaka ◽  
Satish Kumar ◽  
Bhagat Singh ◽  
Karmal Singh ◽  
Amit Kumar ◽  
...  
Keyword(s):  
Nitrogen Use Efficiency ◽  
N Uptake ◽  
Utilization Efficiency ◽  
N Balance ◽  
Flower Initiation ◽  
Recovery Efficiency ◽  
Nitrogen Use ◽  
Total N ◽  
Yield Attributes ◽  
Use Efficiency

An experiment was conducted to study nitrogen use efficiency in pigeonpea at Research farm, CCS Haryana Agricultural University, Hisar, India having three nipping treatments (no nipping, nipping at just start of branching and nipping at flower initiation) and five fertility levels (control, 20 kg N + 40 kg P2O5/ha, 30 kg N + 40 kg P2O5 /ha, 40 kg N + 40 kg P2O5/ha and 20 kg N + 40 kg P2O5/ha + foliar spray of 2% N immediately after nipping) replicated thrice in split plot design during growing seasons of 2016 and 2017. Nipping at start of branching reduced the plant height, while increased primary and secondary branches, pods/plant and yield over no nipping. Significantly higher total N uptake, protein content, net return, B: C, agronomical NUE, physiologic NUE, agro-physiologic NUE, apparent recovery efficiency, utilization efficiency of N and partial N balance were improved with nipping at start of branching. Among fertility levels, 40 kg N + 40 kg P2O5 / ha recorded significantly higher yield attributes with 39.7 per cent higher seed yield over control. Significantly higher agronomic NUE, physiologic NUE, agro-physiological NUE, apparent recovery efficiency, utilization efficiency of N, partial N balance and NER were recorded with 20 kg/ha as compared to higher nitrogen doses.

N uptake, N partitioning, and photosynthetic N-use efficiency of an old and a new maize hybrid

1994 ◽  
Vol 74 (3) ◽  
pp. 479-484 ◽  
Author(s):  
D. E. McCullough ◽  
A. Aguilera ◽  
M. Tollenaar
Keyword(s):  
Dry Matter ◽  
N Uptake ◽  
N Use Efficiency ◽  
Maize Hybrid ◽  
Unit Leaf ◽  
N Supply ◽  
N Partitioning ◽  
Use Efficiency ◽  
N Use ◽  
Leaf N

An old maize (Zea mays L.) hybrid (Pride 5) has been shown to be less tolerant to N stress than a new maize hybrid (Pioneer 3902) during early phases of development. The objective of this study was to quantify the response of the two hybids to N supply in terms of N uptake, N partitioning, and photosynthetic N–use efficiency. Plants were grown under controlled-environment conditions until the 12-leaf stage at three levels of N supply (i.e., 15 mM N, 2.5 mM N, and 0.5 mM N) and were sampled at the 4-, 8-, and 12-leaf stages. Rates of N uptake per unit ground area were higher for Pioneer 3902 than for Pride 5 under maximum N stress during the 8- to 12-leaf phase, but rates were higher for Pride 5 at high N. Rates of N uptake per unit root weight were higher for Pioneer 3902 than for Pride 5 under both medium and low N supply. The old hybrid (Pride 5) partitioned more dry matter and N to leaves than the new hybrid under low N supply, but leaf N per unit leaf area was higher for the new hybrid. The new hybrid (Pioneer 3902) maintained greater rates of leaf photosynthesis per unit leaf N regardless of N supply. Consequently, results indicate that the higher N-use efficiency of Pioneer 3902 under low N supply is associated with higher N uptake and a higher leaf N per unit leaf area. Key words:Zea mays L., dry matter accumulation, photosynthesis, leaf N

scholarly journals Nitrogen Leaching, Water, and Nitrogen Use Efficiency of Citrus Trees Fertilized at Three Rates of Nitrogen

HortScience ◽  
1995 ◽  
Vol 30 (4) ◽  
pp. 780C-780
Author(s):  
Jim Syvertsen ◽  
M.L. Smith
Keyword(s):  
Water Use ◽  
N Uptake ◽  
Fruit Yield ◽  
N Leaching ◽  
Volkamer Lemon ◽  
Canopy Volume ◽  
Leaf N Concentration ◽  
Use Efficiency ◽  
N Rates ◽  
Leaf N

Effects of nitrogen (N) rate and rootstock on tree growth, fruit yield, evapotranspiration, N uptake, and N leaching were measured over a 2-year period. Four-year-old `Redblush' grapefruit trees on either sour orange (SO), a relatively slow-growing rootstock, or `Volkamer' lemon (VL), a more-vigorous rootstock, were transplanted into 7.9-m3 drainage lysimeter tanks filled with native sand and fertilized at three N rates. N rates averaged from about 14% to 136% of the recommended rate when trees were 5 and 6 years old. More N leached below trees on SO as trees on VL had greater N uptake efficiency. Canopy volume and leaf N concentration increased with N rate, but rootstock had no effect on leaf N. Fruit yield of trees on SO was not affected by N rate, but high N increased water use and yield for larger trees on VL. Canopy growth or yield per volume of water used (water use efficiency) was lowest at low N, but N use efficiency was highest at the low N rates.

scholarly journals How Nitrogen Supply Affects Growth and Nitrogen Uptake, Use Efficiency, and Loss from Citrus Seedlings

1996 ◽  
Vol 121 (1) ◽  
pp. 105-114 ◽  
Author(s):  
John D. Lea-Cox ◽  
James P. Syvertsen
Keyword(s):  
Plant Growth ◽  
N Uptake ◽  
Single Application ◽  
N Application ◽  
N Supply ◽  
N Concentration ◽  
Leaf N Concentration ◽  
Use Efficiency ◽  
Complete Nutrient Solution ◽  
Leaf N

We examined how N supply affected plant growth and N uptake, allocation and leaching losses from a fine sandy soil with four Citrus rootstock species. Seedlings of `Cleopatra' mandarin (Citrus reticulata Blanco) and `Swingle' citrumelo (C. paradisi × P. trifoliata) were grown in a glasshouse in 2.3-liter pots of Candler fine sand and fertilized weekly with a complete nutrient solution containing 200 mg N/liter (20 mg N/week). A single application of 15NH415NO3(17.8% atom excess 15N) was substituted for a normal weekly N application when the seedlings were 22 weeks old (day O). Six replicate plants of each species were harvested at 0.5, 1.5, 3.5, 7, 11, and 30 days after 15N application. In a second experiment, NH4 NO3 was supplied at 18,53, and 105 mg N/week to 14-week-old `Volkamer' lemon (C. volkameriana Ten. & Pasq.) and sour orange (C. aurantium L.) seedlings in a complete nutrient solution for 8 weeks. A single application of 15NH415NO3 (23.0% 15N) was substituted at 22 weeks (day 0), as in the first experiment, and seedlings harvested 3,7, and 31 days after 15N application. Nitrogen uptake and partitioning were similar among species within each rate, but were strongly influenced by total N supply and the N demand by new growth. There was no 15N retranslocation to new tissue at the highest (105 mg N/week) rate, but N supplies below this rate limited plant growth without short-term 15N reallocation from other tissues. Leaf N concentration increased linearly with N supply up to the highest rate, while leaf chlorophyll concentration did not increase above that at 53 mg N/week. Photosynthetic CO2 assimilation was not limited by N in this study; leaf N concentration exceeded 100 mmol·m-2 in all treatments. Thus, differences in net productivity at the higher N rates appeared to be a function of increased leaf area, but not of leaf N concentration. Hence, N use efficiency decreased significantly over the range of N supply, whether expressed either on a gas-exchange or dry weight basis. Mean plant 15N uptake efficiencies after 31 days decreased from 60% to 47% of the 15N applied at the 18,20, and 53 mg N/week rates to less than 33% at the 105 mg N/week rate. Leaching losses increased with N rate, with plant growth rates and the subsequent N requirements of these Citrus species interacting with residual soil N and potential leaching loss.

scholarly journals Improvement of Root Characteristics Due to Nitrogen, Phosphorus, and Potassium Interactions Increases Rice (Oryza sativa L.) Yield and Nitrogen Use Efficiency

Agronomy ◽  
2021 ◽  
Vol 12 (1) ◽  
pp. 23
Author(s):  
Ming Du ◽  
Wenzhong Zhang ◽  
Jiping Gao ◽  
Meiqiu Liu ◽  
Yan Zhou ◽  
...  
Keyword(s):  
Grain Yield ◽  
Root Length ◽  
N Uptake ◽  
N Use Efficiency ◽  
Root Characteristics ◽  
Nitrogen Use ◽  
Total N ◽  
Absorption Area ◽  
Use Efficiency ◽  
N Use

Although nitrogen (N), phosphorus (P), and potassium (K) co-application improves crop growth, yield, and N use efficiency (NUE) of rice, few studies have investigated the mechanisms underlying these interactions. To investigate root morphological and physiological characteristics and determine yield and nitrogen use parameters, rhizo-box experiments were performed on rice using six treatments (no fertilizer, PK, N, NK, NP, and NPK) and plants were harvested at maturity. The aboveground biomass at the elongating stage and grain yield at maturity for NPK treatment were higher than the sum of PK and N treatments. N, P, and K interactions enhanced grain yield due to an increase in agronomic N use efficiency (NAE). The co-application of N, P, and K improved N uptake and N recovery efficiency, exceeding the decreases in physiological and internal NUE and thereby improving NAE. Increases in root length and biomass, N uptake per unit root length/root biomass, root oxidation activity, total roots absorption area, and roots active absorption area at the elongating stage improved N uptake via N, P, and K interactions. The higher total N uptake from N, P, and K interactions was due to improved root characteristics, which enhanced the rice yield and NUE.

scholarly journals Genotypic Effects of Fertilization on Seedling Sweetgum Biomass Allocation, N Uptake, and N Use Efficiency

2001 ◽  
Vol 1 ◽  
pp. 407-414 ◽  
Author(s):  
Scott X. Chang ◽  
Daniel J. Robison
Keyword(s):  
Biomass Production ◽  
N Uptake ◽  
N Use Efficiency ◽  
Total N ◽  
Nutrient Use ◽  
Use Efficiency ◽  
P Application ◽  
N Use ◽  
Nutrient Use Efficiencies ◽  
N Additions

Screening and selecting tree genotypes that are responsive to N additions and that have high nutrient use efficiencies can provide better genetic material for short-rotation plantation establishment. A pot experiment was conducted to test the hypotheses that (1) sweetgum (Liquidambar styraciflua L.) families have different patterns in biomass production and allocation, N uptake, and N use efficiency (NUE), because of their differences in growth strategies, and (2) sweetgum families that are more responsive to N additions will also have greater nutrient use efficiencies. Seedlings from two half-sib families (F10022 and F10023) that were known to have contrasting responses to fertility and other stress treatments were used for an experiment with two levels of N (0 vs. 100 kg N/ha equivalent) and two levels of P (0 vs. 50 kg P/ha equivalent) in a split-plot design. Sweetgum seedlings responded to N and P treatments rapidly, with increases in both size and biomass production, and those responses were greater with F10023 than with F10022. Growth response to N application was particularly strong. N and P application increased the proportional allocation of biomass to leaves. Under increased N supply, P application increased foliar N concentration and content, as well as total N uptake by the seedlings. However, NUE was decreased by N addition and was higher in F10023 than in F10022 when P was not limiting. A better understanding of genotype by fertility interactions is important in selecting genotypes for specific site conditions and for optimizing nutrient use in forestry production.

scholarly journals Net Carbon Dioxide Assimilation, Carbon Isotope Discrimination, Growth, and Water-use Efficiency of Citrus Trees in Response to Nitrogen Status

1997 ◽  
Vol 122 (2) ◽  
pp. 226-232 ◽  
Author(s):  
J.P. Syvertsen ◽  
M.L. Smith ◽  
J. Lloyd ◽  
G.D. Farquhar
Keyword(s):  
Water Use Efficiency ◽  
Water Use ◽  
Leaf Tissue ◽  
N Availability ◽  
Isotope Discrimination ◽  
Volkamer Lemon ◽  
Woody Root ◽  
Use Efficiency ◽  
Whole Tree ◽  
Leaf N

Five- to six-year-old `Redblush' grapefruit (Citrus paradisi Macf.) trees on `Volkamer' lemon [VL = C. volkameriana (Ten. & Pasq.)] or sour orange (SO = C. aurantium L.) rootstock, were grown individually in 7.9-m3 lysimeters for 2.5 years using low to high rates of fertilizer N. Net CO2 assimilation (ACO2) of leaves and leaf dry mass per area (DM/a) increased with leaf N concentration, whereas leaf tissue C isotope discrimination (Δ) decreased. Leaf tissue Δ was negatively related to ACO2 and DM/a. Transient effects of rootstock on leaf N were reflected by similar effects on Δ. There was no effect of leaf N on water-use efficiency (WUE) of leaves (WUEL = ACO2/transpiration); WUEL was not correlated with Δ. Although photosynthetic N use efficiency (ACO2/N) consistently decreased with increased leaf N, Δ was not consistently related to ACO2/N. Annual canopy growth, tree evapotranspiration (ET), and fruit yield increased with whole tree N uptake. Leaf tissue Δ was negatively related to all of these tree measurements at the end of the second year. By that time, whole-tree WUE (WUET, annual canopy growth per ET) also was negatively related to Δ. Larger trees on VL had higher ET than trees on SO, but there were no rootstock effects on WUET or on Δ. Leaf tissue Δ was consistently higher than Δ values of trunk and woody root tissues. Citrus leaf tissue Δ can be a useful indicator of leaf N, characteristics of leaf gas exchange, tree growth, yield, and WUET in response to N availability.

Protein production and nitrogen utilization by barley cultivars in response to nitrogen fertilizer under varying moisture conditions

1991 ◽  
Vol 71 (4) ◽  
pp. 997-1009 ◽  
Author(s):  
C. A. Grant ◽  
L. E. Gauer ◽  
L. D. Bailey ◽  
D. T. Gehl
Keyword(s):  
Protein Concentration ◽  
N Uptake ◽  
Protein Yield ◽  
N Use Efficiency ◽  
High Moisture ◽  
Total N ◽  
Barley Cultivars ◽  
Use Efficiency ◽  
Moisture Conditions ◽  
N Use

In a 3-yr field experiment, six barley cultivars — one conventional height malting type, two semidwarf, two conventional height, and one short feed type — were grown at three sites, with six nitrogen application rates ranging from 0 to 200 kg ha−1, to determine the effects of cultivar and N level on N utilization under varying moisture conditions. Nine site-years of data were divided into three levels, low, moderate, and high, based on estimated moisture supply. As moisture level increased, protein concentration of the barley cultivars decreased, while protein yield and total N uptake increased. Cultivars with higher grain yield tended to be lower in protein concentration, but higher in protein yield, total N uptake and N use efficiency than those with lower grain yields. Differences among the cultivars in protein concentration were greater at low than high moisture levels, while differences due to N application were greater at high than low moisture levels. Within the range of N applied, nitrogen use efficiency decreased at high N levels under low and moderate moisture conditions, but was relatively constant at high moisture levels. Protein concentration response to N applications differed slightly among cultivars at all moisture levels, but cultivar by N level interactions in protein yield response only occurred under high moisture conditions. Cultivars respond similarly to N applications in terms of straw N concentration, total N uptake and N use efficiency. Key words: N, nitrogen, barley (Hordeum vulgare), moisture, protein, N use efficiency

scholarly journals Temporal and Organ-specific Responses in NUE Traits to N Fertilization, Fungicide Intensity and Early Sowing in Winter Wheat Cultivars

Agronomy ◽  
2019 ◽  
Vol 9 (6) ◽  
pp. 313 ◽  
Author(s):  
Lukas Prey ◽  
Moritz Germer ◽  
Urs Schmidhalter
Keyword(s):  
Winter Wheat ◽  
Harvest Index ◽  
N Uptake ◽  
N Fertilization ◽  
N Use Efficiency ◽  
Control Treatment ◽  
Total N ◽  
Organ Specific ◽  
Use Efficiency ◽  
N Use

Fungicide intensity and sowing time influence the N use efficiency (NUE) of winter wheat but the underlying mechanisms, interactions of plant traits, and the temporal effects are not sufficiently understood. Therefore, organ-specific responses in NUE traits to fungicide intensity and earlier sowing were compared at two nitrogen (N) levels for six winter wheat cultivars in 2017. Plants were sampled at anthesis and at maturity and separated into chaff, grain, culms, and three leaf layers to assess their temporal contribution to aboveground dry matter (DM) and N uptake (Nup). Compared to the control treatment, across cultivars, the treatment without fungicide mostly exerted stronger and inverse effects than early sowing, on grain yield (GY, −12% without fungicide, +8% n.s. for early sowing), grain Nup (GNup, −9% n.s., +5% n.s.) as well as on grain N concentration (+4%, −2% n.s.). Grain yield in the treatment without fungicide was associated with similar total DM, as observed in the control treatment but with lower values in harvest index, thousand kernel weight, N use efficiency for GY (NUE) and N utilization efficiency. Lower GNup was associated with similar vegetative N uptake but lower values in N translocation efficiency and N harvest index. In contrast, early sowing tended to increase total DM at anthesis and maturity as well as post-anthesis assimilation, at similar harvest index and increased the number of grains per spike and total N use efficiency. Total N uptake increased after the winter season but was similar at anthesis. Although the relative N response in many traits was lower without fungicide, few fungicide x interactions were significant, and the sowing date did not interact either with N fertilization for any of the N and DM traits. The results demonstrate the positive effects of fungicides and earlier sowing on various traits related to yield formation and the efficient use of nitrogen and are discussed based on various concepts.

Sign in / Sign up

Export Citation Format

Share Document