scholarly journals Nitrogen and Water Rates for Subsurface Trickle-irrigated Romaine Lettuce

HortScience ◽  
1995 ◽  
Vol 30 (6) ◽  
pp. 1233-1237 ◽  
Author(s):  
Thomas L. Thompson ◽  
Thomas A. Doerge

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.

HortScience ◽  
1995 ◽  
Vol 30 (7) ◽  
pp. 1382-1387 ◽  
Author(s):  
Thomas L. Thompson ◽  
Thomas A. Doerge

Three field experiments using subsurface trickle irrigation with various rates of target soil water tension (SWT) and N rates were conducted in southern Arizona during 1990–93. The experiments were conducted with collard (Brassica oleracea L. Acephela Group cv. Vates), mustard [Brassica juncea (L.) Czerniak cv. Southern Giant], and spinach (Spinacea oleracea L. cv. Indian Summer). The interactive effects of water and N treatments on crop yield, N uptake, and unutilized fertilizer N were studied. In general, excessive irrigation (SWT <5.6 kPa) resulted in lower yield and N uptake and higher unutilized fertilizer N. Optimum SWTs were 9 kPa for collard, 8 kPa for spinach, and 6 to 10 kPa for mustard.


2016 ◽  
Vol 155 (2) ◽  
pp. 261-281 ◽  
Author(s):  
S. E. ROQUES ◽  
D. R. KINDRED ◽  
S. CLARKE

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.


Soil Research ◽  
1989 ◽  
Vol 27 (4) ◽  
pp. 685 ◽  
Author(s):  
PE Bacon ◽  
LG Lewin ◽  
JW McGarity ◽  
EH Hoult ◽  
D Alter

The fate of 15N-labelled fertilizer applied to rice (Oryza sativa L) was studied in microplots established within two field experiments comprising a range of stubble levels, stubble management techniques, N application rates and times. The first experiment investigated uptake of soil and fertilizer N in plots where application of 0 or 100 kg N ha-1 to the previous rice crop had produced 11.5 and 16.1 t ha-1 of stubble respectively. The stubble was then treated in one of four ways-burn (no till); burn then cultivated; incorporated in autumn or incorporated at sawing. Microplots within these large plots received 60 kg ha-1 of 5% 15N enriched urea at sowing, just prior to permanent flood (PF), or just after panicle initiation (PI) of the second crop. The second experiment was undertaken within a field in which half of the plots had stubble from the previous three rice crops burned, while the other plots had all stubble incorporated. In the fourth successive rice crop, the two stubble management systems were factorially combined with three N rates (0, 70 or 140 kg N ha-1) and three application times (PF, PI or a 50 : 50 split between PF and PI). Nitrogen uptake and retention in the soil were studied within 15N-labelled microplots established within each of these large plots. Only 4% of the 15N applied at sowing in the first experiment was recovered in the rice crop, while delaying N application to PF or PI increased this to an average of 20% and 44% respectively over the two experiments. The doubling of N application rate doubled fertilizer N uptake and also increased uptake of soil N at maturity by 12 kgN ha-1. Three years of stubble incorporation increased average uptake of fertilizer and soil N in the second experiment by 5 and 12 kg N ha-1 respectively. In both experiments, the soil was the major source of N, contributing 66-96% of total N uptake. On average, in the fourth crop, 20% of fertilizer N was in the grain, 12% in the straw and 3% in the roots, while 23% was located in the top 300 mm of soil. A further 3% was in the soil below 300 mm. The remaining 39% was lost, presumably by denitrification.


2020 ◽  
Vol 56 (5) ◽  
pp. 688-698
Author(s):  
Ali M. Ali

AbstractProximal plant sensing with active canopy sensors offers a leap in the non-destructive assessment of crop agronomic information. For managing fertilizer nitrogen (N), sensor readings must be translated using functional models or algorithms to fertilizer amounts. Six field experiments were conducted in three wheat seasons in the West Nile Delta in Egypt to develop and validate an algorithm based on GreenSeeker canopy reflectance sensor for field-specific fertilizer N management in wheat, which takes into account both spatial and temporal variability of N during the crop growth season. The proposed algorithm is based on the prediction of total N uptake and response index of N uptake determined from normalized difference vegetation index measured by the sensor from plots differing in yield potential as established by applying a range of fertilizer N levels in the four experiments conducted in the first two wheat seasons. The treatments in the two experiments conducted in the third wheat season were designed to define appropriate fertilizer N management prior to applying a sensor-based dose at Feekes 6 stage (jointing stage). The application of 40 and 60 kg N ha−1 at 10 and 30 days after sowing of wheat and a sensor-guided dose of N estimated by using the algorithm developed in this study resulted in yields similar to those obtained by following the general recommendation, but with an average of 66 kg N ha−1 less fertilizer N. These results were also reflected in a substantial increase in N recovery (21.9%) and agronomic (7.7 kg grain kg−1 N) efficiencies compared with the general recommendation, thereby proving the usefulness of the sensor-based algorithm in optimizing fertilizer N management in wheat.


2008 ◽  
Vol 17 (1) ◽  
pp. 73 ◽  
Author(s):  
A. NYKÄNEN ◽  
A. GRANSTEDT ◽  
L. JAUHIAINEN

Legume-based leys form the basis for crop rotations in organic farming as they fix nitrogen (N) from the atmosphere for the succeeding crops. The age, yield, C:N, biological N fixation (BNF) and total N of red clover-grass leys were studied for their influence on yields, N uptake and N use efficiency (NUE) of the two sequential cereal crops planted after the leys. Mineral N in deeper soil (30-90 cm) was measured to determine N leaching risk. Altogether, four field experiments were carried out in 1994-1998 at two sites. The age of the ley had no significant effect on the yields and N uptake of the two subsequent cereals. Surprisingly, the residual effect of the leys was negligible, at 0–20 kg N ha-1yr-1. On the other hand, the yield and C:N of previous red clover-grass leys, as well as BNF-N and total-N incorporated into the soil influenced subsequent cereals. NUEs of cereals after ley incorporation were rather high, varying from 30% to 80%. This might indicate that other factors, such as competition from weeds, prevented maximal growth of cereals. The mineral N content deeper in the soil was mostly below 10 kg ha-1 in the sandy soil of Juva, but was 5-25 kg ha-1 in clayey soil of Mietoinen.;


1989 ◽  
Vol 37 (3) ◽  
pp. 269-272
Author(s):  
J.H.G. Slangen ◽  
G.J. Krook ◽  
C.H.M. Hendriks ◽  
N.A.A. Hof

The effect of different amounts (0, 75, 150 and 225 kg/ha) and timings of split application of N on yield and nutrient uptake of 3 hybrid cultivars grown for bulbs was investigated. Efficiency of N-uptake was determined by soil and plant analysis with field experiments in 1983, 1984 and 1985. Leaching of fertilizers applied before planting induced low nutrient efficiencies in sandy soils. Dividing the total N-dressings into 4 monthly applications from Mar. to June or Apr. to July led to a higher N-efficiency, though fertilizers were easily leached with high rainfall. A total of 150 kg N/ha appeared to be adequate. Concentrations of plant nutrients (P, K, Ca, Mg and Na) in mature plants of cultivars Aristo, Connecticut King and Enchantment are presented in relation to bulb yield and N-uptake. (Abstract retrieved from CAB Abstracts by CABI’s permission)


2019 ◽  
Vol 99 (3) ◽  
pp. 345-355
Author(s):  
Richard E. Engel ◽  
Carlos M. Romero ◽  
Patrick Carr ◽  
Jessica A. Torrion

Fertilizer NO3-N may represent a benefit over NH4-N containing sources in semiarid regions where rainfall is often not sufficient to leach fertilizer-N out of crop rooting zones, denitrification concerns are not great, and when NH3 volatilization concerns exist. The objective of our study was to contrast plant-N derived from fertilizer-15N (15Ndff), fertilizer-15N recovery (F15NR), total N uptake, grain yield, and protein of wheat (Triticum aestivum L.) from spring-applied NaNO3 relative to urea and urea augmented with urease inhibitor N-(n-butyl)thiophosphoric triamide (NBPT). We established six fertilizer-N field trials widespread within the state of Montana between 2012 and 2017. The trials incorporated different experimental designs and 15N-labeled fertilizer-N sources, including NaNO3, NH4NO3, urea, and urea + NBPT. Overall, F15NR and 15Ndff in mature crop biomass were significantly greater for NaNO3 than urea or urea + NBPT (P < 0.05). Crop 15Ndff averaged 53.8%, 43.9%, and 44.7% across locations for NaNO3, urea, and urea + NBPT, respectively. Likewise, crop F15NR averaged 52.2%, 35.8%, and 38.6% for NaNO3, urea, and urea + NBPT, respectively. Soil 15N recovered in the surface layer (0–15 cm) was lower for NaNO3 compared with urea and urea + NBPT. Wheat grain yield and protein were generally not sensitive to improvements in 15Ndff, F15NR, or total N uptake. Our study hypothesis that NaNO3 would result in similar or better performance than urea or urea + NBPT was confirmed. Use of NO3-N fertilizer might be an alternative strategy to mitigate fertilizer-N induced soil acidity in semiarid regions of the northern Great Plains.


1984 ◽  
Vol 64 (4) ◽  
pp. 563-570 ◽  
Author(s):  
M. R. CARTER ◽  
D. A. RENNIE

Growth chamber and field studies were conducted to assess the relative utilization of placed and broadcast 15N-urea by spring wheat. The field studies were conducted on zero and conventional (shallow) tillage systems, of 4-yr duration, located on Chernozemic soils at two locations in Saskatchewan. Placement below the seeding depth in comparison to broadcast application, generally reduced fertilizer N immobilization and increased fertilizer N uptake, recovery, and efficiency. Under moisture stress, placed applications were effective in enhancing dry matter yield and total N uptake. It is concluded that fertilizer N placement for these two contrasting tillage systems should be identical, thus some soil disturbance under zero tillage may be necessary to achieve optimum crop use of applied fertilizer N. The dominant N transformation processes and possible tillage induced differences, in regard to methods of N application, are discussed. Key words: Placed and broadcast N application, N efficiency, N utilization, 15N-urea, zero tillage, soil moisture


1997 ◽  
Vol 77 (4) ◽  
pp. 543-551 ◽  
Author(s):  
F. S. Rembon ◽  
A. F. MacKenzie

Soybean (Glycine max L. Merill) can produce high-N residues that may benefit subsequent corn (Zea mays L.) production, but the degree of benefit is often unpredictable and may be related to tillage methods. This study investigated the effects of conventional-tillage (CT) and no-tillage (NT) on fertilizer replacement values for corn in a corn-soybean rotation. Field experiments were conducted for two growing seasons on two soils, a Ste. Rosalie clay (Humic Gleysol), and an Ormstown silty clay (Humic Gleysol). Continuous corn, corn following soybean, soybean following corn, continuous soybean, and three levels of fertilizer N (0, 90, 180 and 0, 20, and 40 kg N ha−1 for corn and soybean, respectively) were compared. Tillage did not effect yield or N uptake consistently. Corn grain yields and N uptake were greater following soybean than following corn. Soybean provided N fertilizer credits ranging from 40 to 150 kg N ha−1, which was greater than the residual NO3 in the soil prior to planting. Credits were greater in the year with higher corn yields and lower previous winter precipitation resulting in greater NO3 carryover. Tillage effects on N credits from soybean differed between the sites. Consequently, N contributions of soybean to corn could not be related to tillage method or soil type. Key words:Zea mays L., Glycine max L. Merill, rotations, grain yield, N uptake, tillage, fertilizer N


2011 ◽  
Vol 21 (3) ◽  
pp. 266-273 ◽  
Author(s):  
Paolo Benincasa ◽  
Marcello Guiducci ◽  
Francesco Tei

Nitrogen (N) use efficiency (NUE) of crops is examined by taking into account both plant N uptake efficiency, focusing on the recovery of fertilizer-N, and the utilization efficiency of the absorbed N. The latter is further analyzed as the overall effect of the absorbed N on crop leaf area, light absorption, photosynthesis, crop growth, biomass partitioning, and yield. The main sources of variation for the NUE of crops are considered, and several of them are discussed based on results from field experiments carried out at the University of Perugia (central Italy) between 1991 and 2008 on sweet pepper (Capsicum annuum), lettuce (Lactuca sativa), and processing tomato (Solanum lycopersicum). More specifically, the effects of species, cultivar, fertilizer-N rate, form and application method (mineral and organic fertilization, green manuring, fertigation frequency), and sink limitation are reported. Implications for residual N in the soil and leaching risks are also discussed. The fertilizer-N rate is the main factor affecting crop NUE for a given irrigation management and rainfall regime. Indeed, avoiding over fertilization is the first and primary means to match a high use efficiency and economic return of fertilizer-N with limited environmental risks from nitrate leaching. The form and application method of fertilizer-N also may affect the NUE, especially in the case of limiting or overabundant N supply. Particularly, high fertigation frequency increased the recovery of fertilizer-N by the crop. It is suggested that species-specific curves for critical N concentration (i.e., the minimum N concentration that allows the maximum growth) can be the reference to calibrate the quick tests used to guide dynamic fertilization management, which is essential to achieve both the optimal crop N nutritional status and the maximum NUE.


Sign in / Sign up

Export Citation Format

Share Document