Sustaining productivity of a Vertisol at Warra, Queensland, with fertilisers, no-tillage or legumes. 2. Long-term fertiliser nitrogen needs to enhance wheat yields and grain protein

1996 ◽  
Vol 36 (6) ◽  
pp. 665 ◽  
Author(s):  
WM Strong ◽  
RC Dalal ◽  
EJ Weston ◽  
JE Cooper ◽  
KJ Lehane ◽  
...  

Cereal production in the summer-dominant rainfall region of Australia, especially the north-east, has relied heavily on natural soil fertility. Continued cereal production has so depleted the fertility of some soils that corrective strategies are required to restore the production of high protein wheat needed for domestic and export markets. Application of nitrogen (N) fertilisers, along with other strategies to improve soil N status, was evaluated between 1987 and 1994 on a Vertisol located in an area of unreliable winter rainfall. Responses of wheat grain yield and protein content to applied N (0-150 kg/ha) under zero tillage (ZT) and conventional tillage (CT) were determined each year, except 1991 when severe drought prevented wheat sowing. The ZT practices increased grain yields, particularly in 1988 and 1992-93 when antecedent soil water supplies were moderate (about 1 m wet soil in 1988 and 1992) or low (about 0.6 m wet soil in 1993), apparently due to increased antecedent soil water. Tillage practice had little effect on available nitrate-N (kg/ha) to 1.5 m, but the greater water supply in ZT soil usually benefited the wheat crop when N was applied. Applying N increased returns from 5 of the 7 crops because of grain yield and/or grain protein responses. Grain yield responses were inconsistent in the year of fertiliser application where no N fertiliser had been applied to preceding crops. Nevertheless, grain protein usually increased with increasing N application at sowing, except in 1994, when drought after sowing prevented secondary root development and fertiliser uptake. Where N was applied with each successive crop, the crops receiving small N applications (0, 12.5 or 25 kg/ha.crop) produced grain of a low protein concentration (<10%) and lower yields (<90% maximum yield) than crops which received larger N applications (75 kg/ha.crop). Profits were substantially reduced where the rate of N applied was insufficient to raise grain protein concentration to >11.5%, due to the low market value of low protein wheat, or because of lower grain yields. Routine N application to crops over the period 1987-94, which included the longest drought (1990-94) in the lifetime of most producers, caused similarly inconsistent grain yield increases but increased grain protein concentrations (>11.5%) in all except the first crop (1987). Increased frequency of high protein wheat and a high anticipated market value of the higher protein grain should encourage greater producer confidence with routine application of N throughout this region.

2004 ◽  
Vol 142 (3) ◽  
pp. 319-325 ◽  
Author(s):  
L. C. EMEBIRI ◽  
D. B. MOODY

Nitrogen (N) levels in the soil and N fertilization are among the major factors that affect grain protein concentration (GPC) in malting barley (Hordeum vulgare L.). The use of inherently low protein cultivars might be an advantage in conditions of excessive soil N or in situations where N is applied to maximize yield. In the present study, eight malting barley genotypes were grown under dryland and irrigated conditions to compare their response to four rates of nitrogen (N) application (0, 30, 60 and 120 kg/ha). The trials were carried out in 1998 and 1999 at a site in the Wimmera region of Victoria, Australia, which has a Mediterranean-type environment. Seasonal differences accounted for a large proportion of the observed variation in GPC, but had little influence on variation in grain yield. Nitrogen application significantly increased grain yield and GPC, and decreased kernel weight and plumpness. The rate of response for grain protein was higher under dryland than irrigated conditions, but the genotype-by-nitrogen interaction was not significant under both conditions. To further characterize genotypic response, the method of pattern analysis was used to identify groups of genotypes showing a similar pattern in their response to N application and to relate the patterns to available knowledge about the inherent GPC of their grains. The eight genotypes were clustered into three entry groups, corresponding to low, moderate and high-protein genotypes. There was little difference among groups in the rate of response to N application. However, the genotype group with inherently low GPC maintained the lower protein over those with higher grain protein at the different rates of N application. Under dryland conditions, the low-protein genotypes tended to have less plump kernels with increasing rates of N application than the respective high-protein group.


1981 ◽  
Vol 21 (111) ◽  
pp. 424 ◽  
Author(s):  
WM Strong

Eighteen fertilizer trials, each with five levels of nitrogen (N) and three levels of phosphorus (PI, were conducted on black earth soils of the Darling Downs to establish optimal economic rates of N fertilizer in commercial, irrigated wheat crops. The optimal economic rate of N with a fertilizer: wheat price ratio (kg N: kg grain) of 5:l, the yield response of 100 kg/ha of applied N, the yield without fertilizer, and the yield with fertilizer not limiting were calculated from derived yield response relations at each site. A multi-variate regression procedure was used to determine which soil or crop management factors significantly influenced the rate of N needed to optimize wheat yield. Delay in planting after June 1 and the level of residual mineral N in the soil at planting had strong negative effects on the response to fertilizer and the optimal rate of fertilizer required. The results indicate that yields of irrigated wheat may be below the economic optimum because of sub-optimal applications of N. Other soil and management factors such as available soil P and number of irrigations also affected grain yield. At 1 3 sites low protein wheat (< 1 1.4�1~) was produced with all but the highest two rates of N fertilizer and at two sites even the highest rate produced low protein wheat. The effect of N fertilizer applied at planting on grain protein concentration was changed by the yield response to the fertilizer application. Grain protein concentration was curvilinearly related (R2 = 0.81) to relative grain yield (yield as a proportion of the maximum yield); grain protein was at its minimum at a relative yield of 0.5. Although heavy rates of N fertilizer at planting increased grain protein concentration on a few sites, usually these applications led to an inefficient use of N fertilizer; apparent incorporation of fertilizer N into grain decreased with increasing rate of fertilizer.


2019 ◽  
Vol 58 (1) ◽  
pp. 34-43
Author(s):  
R. Hackett

AbstractThere is relatively little recent information regarding the effect of timing of fertiliser N application to spring barley on grain yield and grain protein concentration (GPC) under Irish conditions. The objectives of this work were to examine the effects of a) timing of the first N application to spring barley (at sowing or at crop emergence), b) altering the proportion of the total N allocation that is applied in the first of two applications and c) delaying a portion of the total N dose until after the tillering phase on grain yield and GPC of spring barley. Twenty experiments were carried out over four seasons (2011–2014) in the south and south-east of Ireland. Results indicated that there was little consistent difference, in terms of grain yield or GPC between applying the first N at sowing compared to where the initial N application was made at crop emergence. Similarly, altering the proportion of N applied in the first application, irrespective of whether the first application was at sowing or at crop emergence, had little effect on either yield or GPC. Delaying the application of a portion (0.2) of the total N until after the tillering stage also had little consistent effect on either yield or GPC. It is concluded that where the majority of N is applied to spring barley before the end of the tillering stage, altering the timing of applications or the proportion of the total applied in each application will have limited effect on grain yield or GPC.


2021 ◽  
Vol 58 (4) ◽  
pp. 530-539
Author(s):  
Rashmi Upadhyay ◽  
Mamta Banjara ◽  
Devidas Thombare ◽  
Shrikant Yankanchi ◽  
Girish Chandel

Understanding the gravity of nutritional significance of rice (Oryza sativa L.) protein, an experiment conducted in Randomized Complete Block Design (RCBD) involving effect of nitrogen (N) rates i.e.,140 kg N/ha, 120 kg N/ha, 100 kg N/ha and 80 kg N/ha on grain protein content, yield parameters and cooking characteristics of polished rice from eight rice genotypes was conducted. N application significantly affected the grain protein content, grain yield, head rice recovery, plant height and effective tillers. In high protein cultivars substantially low to intermediate amylose content and more cooking time was recorded while in low protein counterpart amylose content was comparatively high with low cooking time. Maximum cooking time in polished rice was of 25 min at 180 kg N/ha dose and highest amylose content of about 27% at 80 kg N/ha. Gumminess and hardness of cooked rice and cooking time significantly elevated with increase in N dose. The substantial differences in grain protein content in brown, polished and cooked rice was observed. Cooking revealed the significant increase in protein content ranged from 50%-70% in low protein to high protein genotypes. R-RGM-ATN-47 with highest grain yield of 62.13 q/ha, grain protein content of 10.00 % in polished rice and intermediate amylose appears to be the most promising candidate.


2001 ◽  
Vol 81 (4) ◽  
pp. 505-514 ◽  
Author(s):  
F. Walley ◽  
D. Pennock ◽  
M. Solohub ◽  
G. Hnatowich

A 3-yr field study was initiated in 1996 to examine the different grain yield and grain protein responses of wheat to varied N fertilizer rates in a typical glacial till landscape in Saskatchewan, Canada. Our objective was to assess the agronomic and economic feasibility of variable rate fertilizer (VRF) N application for wheat. Results suggest that spring soil water status largely determined the yield and the protein content of wheat both within different years of the study and between different landscape positions within a given year. Although grain yield was strongly related to spring soil water and was predictable on that basis, the grain yield response of wheat to fertilizer N additions was highly variable due, in part, to the dual role that N played in determining both grain yield and grain protein content. As a consequence of the unpredictable nature of the varied response of wheat to N fertilizer additions, there was little economic rationale for using VRF strategies in the 3 yr of this study. However, in the long-term, we believe that VRF N application strategies can be employed to manage N inputs from the perspective of managing and replacing harvested N. Key words: Variable rate fertilizer application, precision farming, nitrogen application, N fertilizer, Saskatchewan


2002 ◽  
Vol 82 (4) ◽  
pp. 489-498 ◽  
Author(s):  
B G McConkey ◽  
D. Curtin ◽  
C A Campbell ◽  
S A Brandt ◽  
F. Selles

We examined 1990-1996 crop and soil N data for no-tillage (NT), minimum tillage (MT) and conventional tillage (CT) systems from four long-term tillage studies in semiarid regions of Saskatchewan for evidence that the N status was affected by tillage system. On a silt loam and clay soil in the Brown soil zone, spring what (Triticum aestivum L.) grain yield and protein concentration were lower for NT compared with tilled (CT or MT) systems for a fallow-wheat (F-WM) rotation. Grain protein concentration for continuous wheat (Cont W) was also lower for NT than for MT. For a sandy loam soil in the Brown soil zone, durum (Triticum durum L.) grain protein concentration was similar for MT and NT for both Cont W and F-W, but NT had higher grain yield than MT (P < 0.05 for F-W only). For a loam soil in the Dark Brown soil zone, wheat grain yield for NT was increased by about 7% for fallow-oilseed-wheat (F-O-W) and wheat-oilseed-wheat (W-O-W) rotations. The higher grain yields for NT reduced grain protein concentration by dilution effect as indicated by similar grain N yield. However, at this site, about 23 kg ha-1 more fertilizer N was required for NT than for CT. Elimination of tillage increased total organic N in the upper 7.5 cm of soil and N in surface residues. Our results suggest that a contributing factor to decreased availability of soil N in medium- and fine-textured soils under NT was a slower rate of net N mineralization from organic matter. Soil nitrates to 2.4 m depth did not indicate that nitrate leaching was affected by tillage system. Current fertilizer N recommendations developed for tilled systems may be inadequate for optimum production of wheat with acceptable grain protein under NT is semiarid regions of Saskatchewan. Key words: Tillage intensity, N availability, soil N fractions, N mineralization, crop residue decomposition, grain protein


2002 ◽  
Vol 82 (3) ◽  
pp. 507-512 ◽  
Author(s):  
H. Wang ◽  
M. R. Fernandez ◽  
F. R. Clarke ◽  
R. M. DePauw ◽  
J. M. Clarke

Although leaf spotting diseases have been reported to have a negative effect on grain yield and seed characteristics of wheat (Triticum spp.), the magnitude of such effects on wheat grown on dryland in southern Saskatchewan is not known. A fungicide experiment was conducted at Swift Current (Brown soil) and Indian Head (Black soil) from 1997 to 1999 to determine the effect of leaf spotting diseases on yield and seed traits of wheat. Two fungicides, Folicur 3.6F and Bravo 500, were applied at different growth stages on three common wheat (Triticum aestivum L.) and three durum wheat (T. turgidum L. var durum) genotypes. Fungicide treatments generally did not affect yield, kernel weight, test weight or grain protein concentration, and these effects were relatively consistent among genotypes. Folicur applied at head emergence in 1997 and at flag leaf emergence and/or head emergence in 1998 increased yield at Indian Head (P < 0.05). Fungicides applied at and before flag leaf emergence tended to increase kernel weight. Grain protein concentration increased only in treatments of Bravo applications at Indian Head in 1998. These results suggested that under the dryland environment and management in southern Saskatchewan leaf spotting diseases generally have a small effect on yield, kernel weight, test weight and protein concentration. Key words: Wheat, leaf spotting diseases, fungicide, yield


1996 ◽  
Vol 36 (4) ◽  
pp. 443 ◽  
Author(s):  
MG Mason ◽  
RW Madin

Field trials at Beverley (19911, Salmon Gums (1991; 2 sites) and Merredin (1992; 2 sites), each with 5 rates of nitrogen (N) and 3 levels of weed control, were used to investigate the effect of weeds and N on wheat grain yield and protein concentration during 1991 and 1992. Weeds in the study were grasses (G) and broadleaf (BL). Weeds reduced both vegetative dry matter yield and grain yield of wheat at all sites except for dry matter at Merredin (BL). Nitrogen fertiliser increased wheat dry matter yield at all sites. Nitrogen increased wheat grain yield at Beverley and Merredin (BL), but decreased yield at both Salmon Gums sites in 1991. Nitrogen fertiliser increased grain protein concentration at all 5 sites-at all rates for 3 sites [Salmon Gums (G) and (BL) and Merredin (G)] and at rates of 69 kg N/ha or more at the other 2 sites [Beverley and Merredin (BL)]. However, the effect of weeds on grain protein varied across sites. At Merredin (G) protein concentration was higher where there was no weed control, possibly due to competition for soil moisture by the greater weed burden. At Salmon Gums (G), grain protein concentration was greater when weeds were controlled than in the presence of weeds, probably due to competition for N between crop and weeds. In the other 3 trials, there was no effect of weeds on grain protein. The effect of weeds on grain protein appears complex and depends on competition between crop and weeds for N and for water at the end of the season, and the interaction between the two.


2012 ◽  
Vol 4 (11) ◽  
Author(s):  
Ali Hafeez Malik ◽  
Allan Andersson ◽  
Ramune Kuktaite ◽  
Muhammad Yaqub Mujahid ◽  
Bismillah Khan ◽  
...  

1994 ◽  
Vol 77 (1) ◽  
pp. 184-189 ◽  
Author(s):  
M. Fukue ◽  
V. B. Serikov ◽  
E. H. Jerome

Two routes by which interstitial pulmonary edema liquid may leave the lung during recovery are reabsorption into the pulmonary circulation and clearance by lung lymphatics. We hypothesized that reabsorption of edema liquid of low protein concentration into the pulmonary circulation would be greater than reabsorption of edema liquid of high protein concentration because of the greater protein osmotic gradient in the former. On the basis of previous studies, lymph flow should contribute minimally to the recovery. In 22 in situ perfused sheep lungs with lymph fistulas, we produced approximately 100 g of osmotic or hydrostatic edema (low protein) or increased leakiness edema by calcium depletion (high protein). To induce reabsorption, we changed the perfusate from low- (1% albumin, osmotic pressure = 4 cmH2O) to high-protein (7% albumin, osmotic pressure = 22 cmH2O) solution in the osmotic group, decreased capillary pressure from 29 +/- 9 to 11 +/- 6 cmH2O in the hydrostatic group, or reversed leakiness by adding CaCl2 to the perfusate in the increased leakiness group. Reabsorption occurred only during recovery from osmotic (40 +/- 22% of filtered liquid) and hydrostatic (15 +/- 11%) edema. Total lung lymph flow during recovery from osmotic, hydrostatic, or increased leakiness edema was 4.9 +/- 3.4, 4.3 +/- 3.4, or 3.5 +/- 1.9 g, respectively. We conclude that during recovery from pulmonary edema interstitial liquid is reabsorbed into the circulation in inverse proportion to its protein concentration. We confirm that only a small fraction of the interstitial edema liquid is cleared by the lymphatics during recovery from any type of edema.


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