The use of total nitrogen in youngest fully expanded blades for assessing the nitrogen status of onion (Allium cepa L.) crops

1992 ◽  
Vol 32 (2) ◽  
pp. 245 ◽  
Author(s):  
NA Maier ◽  
AP Dahlenburg ◽  
TK Twigden
Keyword(s):  
Total Nitrogen ◽  
Maximum Yield ◽  
Sampling Time ◽  
Marketable Yield ◽  
Total N ◽  
N Concentration ◽  
Allium Cepa L ◽  
Plant Test ◽  
Low Sensitivity ◽  
Nitrogen Rates

This paper describes the derivation of critical total nitrogen (N) concentrations in youngest fully expanded blades (YFEB), to assess the N status of onion crops. Five rates of N, from 0 to 390 kg/ha, were applied in randomised block experiments to cv. Cream Gold at 2 sites in 1988 and 1989. YFEB were sampled 5 times between the 3- and 9-leaf stages (41-108 days after the 'hook' stage). Marketable yield significantly (P<0.01) increased as the rate of N increased at both sites. Nitrogen rates required for 95% of maximum yield were 230 and 210 kg/ha at sites 1 and 2, respectively. Sensitivity of YFEB total N concentrations to variation in N supply depended on sampling time. For example, at site 2, the increases in total N concentrations due to application of N ranged from 6.3% at 42 days to 36.3% at 93 days. Because of low sensitivity, sampling at the 3-leaf stage may be too early to detect N deficiency reliably. Mean � s.e. increases in total N concentration were 30.6 � 6.1 and 20.3 � 4.9% at sites 1 and 2, respectively. At early sampling times the relationships between relative marketable yield and total N concentration showed a marked Piper-Steenbjerg effect. Critical total N concentrations derived from these relationships decreased from 3.7-40% at 41-42 days to 1.8-1.9% at 106-108 days. This decrease highlights the importance of carefully defining sampling time to ensure correct interpretation of plant test data.

Effect of nitrogen on the yield and quality of irrigated onions (Allium cepa L.) cv. Cream Gold grown on siliceous sands

1990 ◽  
Vol 30 (6) ◽  
pp. 845 ◽  
Author(s):  
NA Maier ◽  
AP Dahlenburg ◽  
TK Twigden
Keyword(s):  
Field Experiments ◽  
Maximum Yield ◽  
Soluble Solids ◽  
Fresh Weight ◽  
Marketable Yield ◽  
Scale Thickness ◽  
Yield And Quality ◽  
Allium Cepa L ◽  
Nitrogen Rates

The effect of nitrogen (N), at rates up to 590 kg N/ha, on the yield and quality of Cream Gold onions grown on siliceous sands was investigated in field experiments conducted during 1987-88 (1 site) and 1988-89 (2 sites). As the rate of applied N increased there was a significant (P<0.001) increase in the fresh weight of tops harvested when the largest bulbs were 25-30 mm in diameter. Fresh weight of tops was significantly (P<0.001) correlated with final marketable yield of bulbs. Nitrogen application accelerated top senescence. Nitrogen-deficient plants had erect green tops at harvest. Marketable yield was significantly (P<0.01) increased and the yield of culls (unmarketable bulbs) was significantly (P<0.01) decreased as the rate of N increased at all sites. Nitrogen rates in the range 299-358 kg N/ha were required for 95% of maximum yield. Scale thickness increased significantly (P<0.05) and glucose and fructose concentrations decreased significantly (P<0.05) at 2 sites as the rate of applied N increased. Soluble solids and dry matter of bulbs were not affected by N. Bulb size increased as the rate of applied N increased, however, the magnitude of the effect varied between sites. Number of days to 10% sprouting during storage at 15 � 0.5�C was significantly increased as the rate of applied N increased up to 40 kg N/ha at 2 sites. We have concluded that for the cv. Cream Gold grown on siliceous sands, the high rates of fertiliser N required to maximise marketable yield and bulb size were not detrimental to quality.

Total nitrogen concentration in leaves of potatoes (Solanum tuberosumL.) as an index of nutritional status

1976 ◽  
Vol 87 (2) ◽  
pp. 293-296 ◽  
Author(s):  
A. Gupta ◽  
M. C. Saxena
Keyword(s):  
Total Nitrogen ◽  
Tuber Yield ◽  
Critical Concentration ◽  
Nitrogen Concentration ◽  
Curvilinear Relationship ◽  
N Application ◽  
Total N ◽  
Potato Plants ◽  
N Concentration ◽  
Total Nitrogen Concentration

SummaryLeaf samples were collected, at weekly intervals, throughout the growing season, from potato (Solanum tuberosumL.) plants supplied with varying amounts of nitrogen (0, 60, 120, 180 and 240 kg N/ha) and analysed for total N. Application of nitrogen increased the N concentration in the green leaves at all stages of growth. There was a significant curvilinear relationship between the final tuber yield and the total N concentration in the leaves at 48–90 days after planting in 1968–9 and at 79–107 days after planting in 1969–70. The N concentration at 70–90 days after planting was consistently related to the final tuber yield in both years. Thus this period was ideal for assessing the nitrogen status of potato plants. The critical concentration of total nitrogen generally decreased with advance in age. It ranged from 4·65% at 76 days to 3·30% at 90 days during 1968–9, whereas in 1969–70 it ranged from 4·20% at 79 days to 3·80% at 93 days. During the period from 83 to 86 days the critical percentage was around 3·6% in both the years.

scholarly journals LEAF TOTAL NITROGEN CONCENTRATION AS AN INDICATOR OF NITROGEN STATUS FOR PLANTLETS AND YOUNG PLANTS OF EUCALYPTUS CLONES

2015 ◽  
Vol 39 (4) ◽  
pp. 1127-1140 ◽  
Author(s):  
Eric Victor de Oliveira Ferreira ◽  
Roberto Ferreira Novais ◽  
Bruna Maximiano Médice ◽  
Nairam Félix de Barros ◽  
Ivo Ribeiro Silva
Keyword(s):  
Total Nitrogen ◽  
Block Design ◽  
Nitrogen Concentration ◽  
Soil N ◽  
Total N ◽  
Chlorophyll Meter ◽  
N Concentration ◽  
Total Nitrogen Concentration ◽  
N Status ◽  
Leaf N

The use of leaf total nitrogen concentration as an indicator for nutritional diagnosis has some limitations. The objective of this study was to determine the reliability of total N concentration as an indicator of N status for eucalyptus clones, and to compare it with alternative indicators. A greenhouse experiment was carried out in a randomized complete block design in a 2 × 6 factorial arrangement with plantlets of two eucalyptus clones (140 days old) and six levels of N in the nutrient solution. In addition, a field experiment was carried out in a completely randomized design in a 2 × 2 × 2 × 3 factorial arrangement, consisting of two seasons, two regions, two young clones (approximately two years old), and three positions of crown leaf sampling. The field areas (regions) had contrasting soil physical and chemical properties, and their soil contents for total N, NH+4-N, and NO−3-N were determined in five soil layers, up to a depth of 1.0 m. We evaluated the following indicators of plant N status in roots and leaves: contents of total N, NH+4-N, NO−3-N, and chlorophyll; N/P ratio; and chlorophyll meter readings on the leaves. Ammonium (root) and NO−3-N (root and leaf) efficiently predicted N requirements for eucalyptus plantlets in the greenhouse. Similarly, leaf N/P, chlorophyll values, and chlorophyll meter readings provided good results in the greenhouse. However, leaf N/P did not reflect the soil N status, and the use of the chlorophyll meter could not be generalized for different genotypes. Leaf total N concentration is not an ideal indicator, but it and the chlorophyll levels best represent the soil N status for young eucalyptus clones under field conditions.

scholarly journals Nitrogen fertilization in banana grown on a highly weathered soil of the humid mountain region of Puerto Rico.

1969 ◽  
Vol 86 (1-2) ◽  
pp. 15-26
Author(s):  
Héber Irizarry ◽  
Ricardo Goenaga ◽  
Ulises Chardón
Keyword(s):  
Total Nitrogen ◽  
Nitrogen Uptake ◽  
Dry Matter ◽  
Nitrogen Concentration ◽  
Maximum Yield ◽  
Leaf Nitrogen ◽  
Dry Matter Production ◽  
Nitrogen Rate ◽  
Matter Production ◽  
Nitrogen Rates

A 40-month experiment was conducted to re-evaluate the nitrogen fertilization recommendation for banana grown on a clayey, mixed isohyperthermic Aquic Haplohumults under rainfed conditions. Five nitrogen rates (0, 85,170, 255 and 340 kg/ha/crop) were arranged in a randomized compíete block design with three replications. The nitrogen treatments were applied with 24.4 kg/ha of phosphorus, 651,7 kg/ha of potassium, and a minor element mixture containing 22.7 kg/t of fertilizer. Treatments were applied every three months. Applications of magnesium alone were also applied between treatments at the rate of 55 kg/ha in the plant crop (PC) and 110 kg/ha in each of two ratoon crops (R1, R2). During growth and development of three crops we collected data of plant and bunch traits, green and oven-dry biomass weight, nitrogen concentration in various plant organs, and bunch marketable weight at harvest. Results showed that the rate x crop interaction was highly significant (P < 0,01) for total nitrogen uptake, and for nitrogen concentration in the leaf-lamina four months before bunch harvest, and significant (P < 0.05) for total dry matter production. Total nitrogen uptake, leaf nitrogen concentration, and total dry matter production linearly increased with increments in the nitrogen rates. Overall total nitrogen uptake and total dry matter production were always significantly higher in the R2 than in the PC, Regardless of the nitrogen rate, a significantly higher nutrient concentration was always found in the leaf-lamina of the R1 plants than in either the PC or the R2 plants. Crop had no significant effect on yield, but nitrogen rate significantly influenced yield. A maximum yield of 57,060 kg/ ha/crop was obtained with an estimated nitrogen application of 240 kg/ha. This amount corresponded to a leaf nitrogen concentration of between 2.75 and 2.85 g/kg. Since the maximum yield for all crops was obtained with a nitrogen application of only 240 kg/ha, we concluded that the linear response to fertilization in excess of this amount for total nitrogen uptake, nutrient concentration, and total dry matter production may be attributed to luxury consumption of nitrogen.

Assessment of the nitrogen status of onions (Allium cepa L.) cv. Cream Gold by plant analysis

1990 ◽  
Vol 30 (6) ◽  
pp. 853 ◽  
Author(s):  
NA Maier ◽  
AP Dahlenburg ◽  
TK Twigden
Keyword(s):  
Field Experiments ◽  
Soluble Solids ◽  
Marketable Yield ◽  
Total N ◽  
Scale Thickness ◽  
Plant Parts ◽  
N Supply ◽  
Nitrate N ◽  
Allium Cepa L ◽  
N Rates

Three field experiments were carried out during 1987-88 (1 site) and 1988-89 (2 sites) with Cream Gold onions grown on siliceous sands, to investigate the effect of nitrogen (N), at rates up to 475 kg N/ha on total-N, nitrate-N, potassium (K) and phosphorus (P) concentrations in youngest fully expanded blades (YFEB), bulked blades, necks and developing bulbs. The plant samples were collected when the largest bulbs were 25-30 mm in diameter. Nitrate-N concentrations were in the order WEB> bulked blades>necks = developing bulbs. For total-N the order was YFEB = bulked blades>necks> developing bulbs. Nitrate-N was more sensitive to variations in N supply than total-N in all tissues sampled. Potassium concentrations were in the order bulked blades > YFEB > necks > bulbs. At N rates <75 kg N/ha, P concentrations were in the order YFEB = bulked blades > bulbs > necks. Coefficients of determination (r2) for the relationships between nitrate-N and total-N concentrations and relative marketable yield of bulbs were in the range 0.73-0.98. At sites 1 and 3, the relationships between total-N and relative marketable yield were 'C-shaped' or showed the Piper-Steenbjerg effect. Critical concentrations (values at 90% relative marketable yield) for nitrate-N varied between plant parts (375-590 mg/kg) and sites (590-940 mg/kg for YFEB). Critical total-N concentrations also varied between the different plant parts (1.2-2.9%) but less so between sites (2.4-2.9% for YFEB) compared with nitrate-N. Based on sensitivity (as indicated by the range in tissue concentrations in response to variations in N supply) and on the correlations between nitrate-N and total-N concentrations and per cent relative marketable yield, we concluded that nitrate-N and total-N concentrations in YFEB were suitable indicators of the N status of onion plants. The YFEB is easily identified, and compared with bulked blades, necks or bulbs, samples of 50-100 can be collected without destroying plants and will also not result in excessive plant material to dry. Based on the variation in critical values between sites (reproducibility), total-N is preferred to nitrate-N. Correlations between nitrate-N and total-N concentrations in YFEB and bulb quality attributes (scale thickness, glucose concentration, fructose concentration, soluble solids and dry matter) were poor (72 values 10.48) and of little predictive value.

scholarly journals Effect of Nitrogen Fertilization on Yield and Canopy Reflectance of Pepper (Capsicum annuum)

HortScience ◽  
2004 ◽  
Vol 39 (4) ◽  
pp. 871C-871
Author(s):  
Paolo Sambo* ◽  
Daniele Borsato ◽  
Giorgio Gianquinto
Keyword(s):  
Capsicum Annuum ◽  
Nitrogen Fertilization ◽  
Maximum Yield ◽  
Growth Cycle ◽  
Fruit Weight ◽  
Nitrate Content ◽  
Canopy Reflectance ◽  
Marketable Yield ◽  
Nitrogen Treatments ◽  
Nitrogen Rates

Research at Padova Univ., Italy, during Summer 2003, was carried out to determine the effect on nitrogen fertilization on yield and canopy reflectance of sweet bell pepper (Capsicum annuum). Pepper var. Tolomeo LRP 4993 (Syngenta) was transplanted into plots (24 m2) on 20 May, maintaining 40 cm between plants and 75 cm between rows (3.3 plant per m2). The experimental design was a randomized block with four replicates. Treatments were 6 nitrogen fertilization rates ranging from 0 to 300 kg·ha-1. Nitrogen was distributed at planting and as top dressing, 44 days after planting. All other production techniques were typical of pepper production in the Veneto region. Beginning the second week after transplanting, canopy reflectance was measured weekly using a multispectral radiometer MSR 87 (Cropscan Rochester, Minn.). Fruits were harvested at breaking color stage starting from 21 July to 9 Oct. (8 harvests). At harvest, total and marketable yield, fruit averaged weight and nitrogen content were determined. Maximum yield was recorded at the 120 kg·ha-1 nitrogen treatment, while higher rates proved ineffective at increasing production. Nitrogen rates positively affected fruit weight. The nitrate content of fruits also increased with the nitrogen rates although it remained below the level dangerous for human health. Canopy reflectance was able to detect the different nitrogen treatments only during the late stages of the growth cycle making difficult its use as a tool to drive nitrogen fertilization.

Petiole sap nitrate is better than total nitrogen in dried leaf for indicating nitrogen status and yield responsiveness of capsicum in subtropical Australia

1994 ◽  
Vol 34 (6) ◽  
pp. 835 ◽  
Author(s):  
JK Olsen ◽  
DJ Lyons
Keyword(s):  
Total Nitrogen ◽  
Nitrate Concentration ◽  
Fruit Yield ◽  
Yield Response ◽  
Total N ◽  
N Concentration ◽  
Marketable Fruit ◽  
Petiole Sap ◽  
N Status ◽  
Subtropical Australia

This study was conducted to assess the usefulness of petiole sap nitrate and total nitrogen (N) in dried leaf for determining N status and yield response in capsicum (Capsicum annuum L.) grown with plastic mulch and trickle irrigation in subtropical Australia. Five rates of N (0, 70, 140,210, 280 kg/ha) were applied in factorial combination with 2 rates of potassium (K: 0, 200 kg/ha) in randomised block experiments to capsicum cv. Bell Tower grown at Bundaberg Research Station in spring 1990 and autumn 1991. Critical nutrient ranges for nitrate concentration in petiole sap and for total N concentration in dried youngest mature leaf blades plus petioles (YMB + P) were derived at different stages of crop development (bud development, BD; first anthesis, FA; 80% flowering, F; fruit set, FS). Sap nitrate was about 5 times more sensitive to changes in N application than total N. Petiole sap nitrate accounted for a greater amount of the variation in marketable fruit yield (quadratic square root relationships, 0.45 < R2 < 0.83) than total N concentration in dried YMB + P (linear relationships, 0.29 < R2 < 0.74). Simple linear regressions indicated a stronger relationship between applied N and petiole sap nitrate concentration than total N concentration in dried YMB + P (range in R2 values among 8 sampling events: 0.71-0.91 for petiole sap nitrate, 0.35-0.78 for YMB + P total N). For the fertiliser application strategy, 60% of N was applied pre-fruitset and 40% after. Sap nitrate concentrations associated with 95 and 100% of maximum marketable fruit yield increased from BD (5010-6000 mg/L spring, 4980-5280 mg/L autumn) to FA (6220-7065 mg/L spring, 555M000 mg/L autumn). After FA, the range progressively decreased to 1640-2800 and 520-1220 mg/L at FS, for spring and autumn, respectively. It was concluded that petiole sap nitrate was a better indicator of plant N status and yield response than total N concentration in dried YMB + P for capsicum in subtropical Australia. A critical petiole sap K concentration (corresponding with maximum yield and at which no yield response to K addition was measured) of >4800 mg/L was proposed by correlating sap K with yield responses.

Growth and N status of Populus in mixture with red alder on recent volcanic mudflow from Mount Saint Helens

1990 ◽  
Vol 20 (1) ◽  
pp. 84-90 ◽  
Author(s):  
Paul E. Heilman
Keyword(s):  
Late Summer ◽  
Height Growth ◽  
Phosphorus Fertilization ◽  
Cross Sectional ◽  
Red Alder ◽  
Total N ◽  
Foliar N ◽  
N Concentration ◽  
The Mean ◽  
Foliar N Concentration

Eleven months after the May 1980 eruption of Mount Saint Helens in southeastern Washington, United States, three Populus clones were planted in an experiment on the Toutle River mudflow deposit. The trees grew at an abnormally slow rate and by 3 years were overtopped by a dense stand (14 600 ± 3600 trees/ha) of red alder seeded naturally onto the site. Over the 6-year period of the study, the total N content of the soil increased an average of 56 kg•ha−1•year−1•. Foliar N concentration in Populus increased significantly from a mean late summer – early autumn value in the 2nd year (1982) of 0.69% N to a value of 2.06% N at the end of the seventh growing season. The mean annual height growth of the largest Populus averaged <0.5 m/year in the first 3 years, increasing to an average of over 1.0 m/year in the 5th and 6th years. Fertilizer treatments with N (as urea) and N + P (as urea plus treble superphosphate) placed in the soil near the individual Populus at a maximum rate of 5.3 g N/tree increased height growth in the year of fertilization (1982) and the following year (the response in height growth for the 2 years totaled 64%). After 1984, no significant effects of fertilizer on height growth, total height, or diameter were evident. Nitrogen fertilization significantly increased foliar N concentration (1.54% N with the highest N treatment vs. 0.69% N in the control) in the year of treatment only. Phosphorus fertilization had no significant effect on growth or foliar P concentration. At 6 years, only 2% of the Populustrichocarpa Torr. & Gray clone and 13% of the tallest Populus hybrid were equal to or above the mean height of alder dominants and codominants (6.2 m). Additionally, the diameter growth of Populus was severely limited: the trees had only 8% of the cross-sectional area of "normal" trees for their height. Results indicated that on sites of low N such as the mudflow, Populus may not compete satisfactorily in mixture with alder. Such behavior is in sharp contrast to sites of high N, where red alder cannot compete with Populus.

scholarly journals Seasonal variation in nitrogen pools and <sup>15</sup>N/<sup>13</sup>C natural abundances in different tissues of grassland plants

2012 ◽  
Vol 9 (5) ◽  
pp. 1583-1595 ◽  
Author(s):  
L. Wang ◽  
J. K. Schjoerring
Keyword(s):  
Seasonal Pattern ◽  
Exchange Potential ◽  
Total N ◽  
Δ13c Values ◽  
Green Leaves ◽  
Nh3 Emission ◽  
N Concentration ◽  
Grassland Plants ◽  
N Assimilation ◽  
Different Tissues

Abstract. Seasonal changes in nitrogen (N) pools, carbon (C) content and natural abundance of 13C and 15N in different tissues of ryegrass plants were investigated in two intensively managed grassland fields in order to address their ammonia (NH3) exchange potential. Green leaves generally had the largest total N concentration followed by stems and inflorescences. Senescent leaves had the lowest N concentration, indicating N re-allocation. The seasonal pattern of the Γ value, i.e. the ratio between NH4+ and H+ concentrations, was similar for the various tissues of the ryegrass plants but the magnitude of Γ differed considerably among the different tissues. Green leaves and stems generally had substantially lower Γ values than senescent leaves and litter. Substantial peaks in Γ were observed during spring and summer in response to fertilization and grazing. These peaks were associated with high NH4+ rather than with low H+ concentrations. Peaks in Γ also appeared during the winter, coinciding with increasing δ15N values, indicating absorption of N derived from mineralization of soil organic matter. At the same time, δ13C values were declining, suggesting reduced photosynthesis and capacity for N assimilation. δ15N and δ13C values were more influenced by mean monthly temperature than by the accumulated monthly precipitation. In conclusion, ryegrass plants showed a clear seasonal pattern in N pools. Green leaves and stems of ryegrass plants generally seem to constitute a sink for NH3, while senescent leaves have a large potential for NH3 emission. However, management events such as fertilisation and grazing may create a high NH3 emission potential even in green plant parts. The obtained results provide input for future modelling of plant-atmosphere NH3 exchange.

scholarly journals The effect of sub-irrigation with untreated and treated municipal wastewater on organic matter and Nitrogen content on two soil types

2019 ◽  
Keyword(s):  
Organic Matter ◽  
Nitrogen Content ◽  
Total Nitrogen ◽  
Municipal Wastewater ◽  
Tap Water ◽  
Soil Mass ◽  
Treated Wastewater ◽  
Total N ◽  
Untreated Wastewater ◽  
Zone Ii

<p>In order to study the chemical parameters of the soil after sub-irrigation with wastewater, a system was installed in one of the greenhouses of the Agricultural University of Athens. Wastewater was applied subsurface into the soil mass of the pots were used. Three treatments were used: Untreated wastewater (U), Treated wastewater (T) and tap water (W) as control. Two different types were used: Soil (a) characterized as Sandy loam and soil (b) characterized as Loamy sand. Moreover, in order to investigate the change of total Nitrogen and organic matter concentrations at the point where the emitter was placed, the soil mass was divided into two zones. The upper (zone I) and the lower one (zone II). The total nitrogen content, ammonia nitrogen (NH4-N), nitrogen nitrate (NO3-N) and the percentage of organic matter, were determined in the soil samples. Statistically significant differences (p &lt;0, 05) were observed in the organic matter and the total N%, only for soil (b). For soil (a), organic matter percentage was increased in zone (I) (irrigation with treated wastewater at 20 cm depth). For soil (b), total N% was increased in zone (I), while nitrate and ammonium were increased in zone (II) (irrigation with untreated wastewater at 20 cm depth).</p>

Sign in / Sign up

Export Citation Format

Share Document