Site-factor Influence on Barley Response to Fertilizer in On-farm Trials in Northern Syria: Descriptive and Predictive Models

1992 ◽  
Vol 28 (1) ◽  
pp. 63-87 ◽  
Author(s):  
M. J. Jones ◽  
A. Wahbi
Keyword(s):  
Rainfall Variability ◽  
Growth Period ◽  
Yield Response ◽  
Regression Equations ◽  
Nitrogen And Phosphorus ◽  
Fertilizer Rate ◽  
Data Set ◽  
Site Factor ◽  
Yield Responses ◽  
Fertilizer Rates

SummaryThe effects of site and rate of application of fertilizer on the grain and straw production of barley were investigated in 75 trials on representative farmers' fields. Grain and straw production were strongly but curvilinearly correlated with growth-period rainfall over the range 136–568 mm, almost irrespective of soil type, previous crop or fertilizer rate, and responded positively to applied nitrogen and/or phosphorus in 74 of the trials. Responses to nitrogen increased and those to phosphorus decreased with increasing rainfall. Yields tended to be lower but responses to nitrogen were higher where barley followed barley and were influenced by the availability of phosphate and mineral nitrogen in the soil at planting time.These results are summarized in regression equations, which express yield quadratically in terms of fertilizer rates, seasonal rainfall and their interactions over the full 75-trial data set and within representative sub-sets. The wide differences in crop response to fertilizer highlight the problem of recommending fertilizer rates for a low and variable rainfall environment. Simple second-order multiple regressions for different geographical areas, rainfall zones, crop rotations etc., based on mean rainfall values, account for around 40% of the variance in yield response to nitrogen and phosphorus fertilizer; only a small proportion of the remaining variance appears attributable to rainfall variability. Alternatively, yield may be expressed as a function of fertilizer rate and rainfall using rainfall probability values derived from long-term records. This can be used to estimate the probabilities of predetermined yield responses for specified sites and fertilizer rates and to produce maps of those probabilities.

Nitrogen and phosphorus requirements of wheat sown by minimum tillage into rice stubble and the effects of rice stubble treatment

1979 ◽  
Vol 19 (99) ◽  
pp. 488 ◽  
Author(s):  
BS Dear ◽  
DJ McDonald ◽  
G Falconer
Keyword(s):  
Nitrogen Fertilizer ◽  
Significant Rise ◽  
Yield Response ◽  
Nitrogen And Phosphorus ◽  
Single Superphosphate ◽  
Minimum Tillage ◽  
Protein Levels ◽  
Highly Correlated ◽  
Yield Responses ◽  
Fertilizer Rates

Egret wheat was sown into rice stubble using a minimum cultivation technique called seedavation. Nitrogen was surface applied as sulphate of ammonia in 1974 and ammonium nitrate in 1975 at 0,60 and 120 kg N ha-1. Phosphorus as single superphosphate was drilled with the seed at 0 and 17.5 kg P ha-1. The effects of burning, incorporating and removing rice stubble were compared. Large grain yield responses to nitrogen were achieved with yields up to 5 t ha-1 despite the use of minimum tillage. Tiller numbers were highly correlated with yield. No yield response to phosphorus was obtained. Low protein levels (less than 10%) suitable for biscuit wheat were obtained even at the high nitrogen fertilizer rates. The effect of stubble treatment varied between years; in 1974 it had no effect on yield; however, in 1975 removing or incorporating stubble reduced yields compared with burning the stubble. These results indicate that in rice growing areas a significant rise in wheat yields can be achieved through the use of higher nitrogen fertilizer rates.

Assessment of the Effects of Environmental Factors on the Response of Wheat to Fertilizer in On-farm Trials in a Mediterranean Type Environment

1996 ◽  
Vol 32 (3) ◽  
pp. 339-349 ◽  
Author(s):  
M. Pala ◽  
A. Matar ◽  
A. Mazid
Keyword(s):  
Seasonal Rainfall ◽  
Fertilizer Treatment ◽  
Regression Equations ◽  
Strongly Correlated ◽  
Soil Mineral ◽  
Wheat Grain ◽  
Soil Mineral Nitrogen ◽  
Fertilizer Rate ◽  
On Farm ◽  
Fertilizer Rates

SUMMARYA series of researcher-managed wheat fertilizer trials was conducted on representative farmers' fields across northwest Syria between 1986 and 1990. Wheat grain and straw yields were strongly correlated with seasonal (October-May) rainfall, almost irrespective of soil fertility, crop sequence or fertilizer rate, with a highly significant response to nitrogen fertilizer which increased with increasing rainfall and decreasing initial soil mineral-nitrogen values. These results were summarized in regression equations which express yield in terms of fertilizer rates, seasonal rainfall and their interactions. The equations with applied nitrogen and seasonal rainfall were the most appropriate for determining fertilizer needs. Economic analysis indicated that all fertilizer treatment rates were profitable under existing price conditions and that fertilizer use would still be beneficial for a nitrogen price up to three times higher than that of the price of grain (weight for weight) with a seasonal rainfall of 250 mm, and up to six times higher with a seasonal rainfall of 450 mm.

Tillage and fertilizer rate effects on yam yield (Dioscorea alata L.)

1969 ◽  
Vol 77 (3-4) ◽  
pp. 153-159
Author(s):  
Wanda I. Lugo ◽  
Héctor M. Lugo ◽  
Agenol González ◽  
Nydia Rafols ◽  
Carlos Almodóvar
Keyword(s):  
Conventional Tillage ◽  
Yield Response ◽  
Dioscorea Alata ◽  
Fertilizer Rate ◽  
Soil Response ◽  
Good Physical Condition ◽  
No Till ◽  
Rate Effects ◽  
Fertilizer Rates ◽  
Recommended Level

In Puerto Rico yam (Dioscorea spp.) is usually planted in thoroughly tilled soils of the mountain region. An experiment was established in an Ultisol (aquic tropudults), a Vertisol (udic chromusterts) and an Oxisol tropeptic haplorthox) to study the effect of tillage and fertilizer rates on yield of the Binugas yam (Dioscorea alata L.). Three tillage treatments (conventional, deep and minimum) were compared to no-till; and three fertilizer levels (0, 1X and 2X the recommended level) were evaluated. The highest yields were observed in the conventionally tilled plots but differences among tillage treatments were significant only in the Ultisol and Vertisol soils. At these sites, yields under no-tillage were significantly lower than those under conventional tillage. No yield response to tillage was observed in the Oxisol, possibly because of the good physical condition of this soil. Response to fertilizer treatments was observed only in the Oxisol, a soil of low native fertility.

scholarly journals Substrate Properties and Fertilizer Rates on Yield Responses of Lettuce in a Vertical Growth System

2020 ◽  
Vol 12 (16) ◽  
pp. 6465
Author(s):  
ZaDarreyal Wiggins ◽  
Onyekachukwu Akaeze ◽  
Dilip Nandwani ◽  
Anthony Witcher
Keyword(s):  
Water Content ◽  
Bulk Density ◽  
Total Porosity ◽  
Fresh Weight ◽  
Fertilizer Rate ◽  
Growth System ◽  
Substrate Properties ◽  
Yield Responses ◽  
Water Holding ◽  
Fertilizer Rates

The increased demand for food and the challenge for space for agriculture production in urban centers have made the vertical growth system an interesting trend. Agriculture is no longer only the horizontal, traditional, and soil grown method. Urban agriculture has created ways for inner city growers to be able to farm in a restricted space. Vertical farming is the practice of growing crops, especially leafy vegetables such as lettuce, in vertically stacked layers, as this results in significantly higher plant population per unit area. Two research trials were conducted in the fall of 2018 and the spring of 2019 to determine the effect of substrate properties and fertilizers on lettuce yield to optimize the urban production of lettuce. Three substrates (P3 + CF7 = Perlite 30%: Coco fiber 70%, PB7 + C3 = Pine Bark 70%: Compost 30%, and PB9 + C1 = Pine Bark 90%: Compost 10%) along with full and half rates of a fertilizer blend (VertiGro Organics fermented molasses, Ohrstrom’s Maxicrop liquid seaweed, and organic mineral blend) were evaluated on fresh and dried weight yield of lettuce. Substrate physical properties (air space, water holding capacity, total porosity, and bulk density) and substrate volumetric water content were also determined. ‘Nevada’ and ‘Optima’ lettuce varieties showed similar yield responses (fresh and dried weight) to substrate and fertilizer rates in both trials. In the fall 2018 trial, the highest fresh weight was observed in substrate PB7 + C3 with half fertilizer rate, with a mean plant weight of 41.13 g and 49.75 g for ‘Optima’ and ‘Nevada’, respectively. The least mean fresh weight was observed in half fertilizer rate of substrate P3 + CF7. For the spring 2019 trial, PB7 + C3 in half fertilizer strength gave the highest fresh weight for ‘Optima’ and ‘Nevada’ (45.64 g and 41.13 g, respectively). These values were statistically comparable to all other treatments except for substrate P3 + CF7 in full and half fertilizer which gave the least mean fresh weight. Volumetric water content in substrates P3 + CF7 recorded the highest average, while PB7 + C3 gave the least. Higher water holding capacity, total porosity, and lower airspace were observed in substrate P3 + CF7. Higher airspace was observed in PB9 + C1 but was comparable to PB7 + C3. PB7 + C3 gave the highest bulk density in both trials.

Factors affecting yield and fertilizer response of sugar beet in Iran

1973 ◽  
Vol 81 (2) ◽  
pp. 311-316
Author(s):  
E. W. Bolle-Jones ◽  
F. Sanei
Keyword(s):  
Sugar Beet ◽  
Field Experiments ◽  
Phosphate Fertilizer ◽  
Fertilizer Application ◽  
Yield Response ◽  
Soil Test ◽  
Nitrogen And Phosphorus ◽  
Fertilizer Response ◽  
High Calcium ◽  
Yield Responses

SummaryField experiments were conducted in four provinces of Iran in which sugar-beet yield responses to added nitrogen and phosphorus fertilizers were correlated with soil test values and number of irrigations.Although significant yield responses to fertilizer application were obtained in all four provinces, extremely few significant relationships were established between soil test values and yield response.Average crop yield was favourably influenced by the number of irrigations applied in Fare and Khorasan, by organic carbon status in Esfahan and Khorasan and adversely affected by increased soil conductivity in Esfahan and Khorasan. These results were taken to imply an inadequate number of irrigations in Fars and Khorasan. The high calcium carbonate status found in Fars soil adversely affected the level of average yield.Response to nitrogen fertilizer declined in Fars and Khorasan as the leaf nitrogen exceeded 3·15 and 4·0% respectively. Response to phosphate fertilizer declined in West Azerbaijan and Khorasan when leaf phosphorus exceeded 0·4%.

scholarly journals Response of wheat, pea, and canola to micronutrient fertilization on five contrasting prairie soils

2020 ◽  
Vol 10 (1) ◽  
Author(s):  
Noabur Rahman ◽  
Jeff Schoenau
Keyword(s):  
Foliar Application ◽  
Relative Effectiveness ◽  
Yield Response ◽  
Soil Extraction ◽  
Dominant Form ◽  
Prairie Soils ◽  
Biomass Yields ◽  
Mineral Soils ◽  
Yield Responses ◽  
Cu And Zn

Abstract A polyhouse study was conducted to evaluate the relative effectiveness of different micronutrient fertilizer formulation and application methods on wheat, pea and canola, as indicated by yield response and fate of micronutrients in contrasting mineral soils. The underlying factors controlling micronutrient bioavailability in a soil–plant system were examined using chemical and spectroscopic speciation techniques. Application of Cu significantly improved grain and straw biomass yields of wheat on two of the five soils (Ukalta and Sceptre), of which the Ukalta soil was critically Cu deficient according to soil extraction with DTPA. The deficiency problem was corrected by either soil or foliar application of Cu fertilizers. There were no significant yield responses of pea to Zn fertilization on any of the five soils. For canola, soil placement of boric acid was effective in correcting the deficiency problem in Whitefox soil, while foliar application was not. Soil extractable Cu, Zn, and B concentration in post-harvest soils were increased with soil placement of fertilizers, indicating that following crops in rotation could benefit from this application method. The chemical and XANES spectroscopic speciation indicates that carbonate associated is the dominant form of Cu and Zn in prairie soils, where chemisorption to carbonates is likely the major process that determines the fate of added Cu and Zn fertilizer.

PSVI-8 Meta-regression Analysis to Determine the Relationship Between Growing Pig Body Weight and Variation

2021 ◽  
Vol 99 (Supplement_1) ◽  
pp. 218-219
Author(s):  
Andres Fernando T Russi ◽  
Mike D Tokach ◽  
Jason C Woodworth ◽  
Joel M DeRouchey ◽  
Robert D Goodband ◽  
...  
Keyword(s):  
Body Weight ◽  
Regression Analysis ◽  
Sample Size ◽  
Polynomial Regression ◽  
Data Sets ◽  
Regression Equations ◽  
Prediction Equations ◽  
Data Set ◽  
Rate Of Increase ◽  
The Relationship

Abstract The swine industry has been constantly evolving to select animals with improved performance traits and to minimize variation in body weight (BW) in order to meet packer specifications. Therefore, understanding variation presents an opportunity for producers to find strategies that could help reduce, manage, or deal with variation of pigs in a barn. A systematic review and meta-analysis was conducted by collecting data from multiple studies and available data sets in order to develop prediction equations for coefficient of variation (CV) and standard deviation (SD) as a function of BW. Information regarding BW variation from 16 papers was recorded to provide approximately 204 data points. Together, these data included 117,268 individually weighed pigs with a sample size that ranged from 104 to 4,108 pigs. A random-effects model with study used as a random effect was developed. Observations were weighted using sample size as an estimate for precision on the analysis, where larger data sets accounted for increased accuracy in the model. Regression equations were developed using the nlme package of R to determine the relationship between BW and its variation. Polynomial regression analysis was conducted separately for each variation measurement. When CV was reported in the data set, SD was calculated and vice versa. The resulting prediction equations were: CV (%) = 20.04 – 0.135 × (BW) + 0.00043 × (BW)2, R2=0.79; SD = 0.41 + 0.150 × (BW) - 0.00041 × (BW)2, R2 = 0.95. These equations suggest that there is evidence for a decreasing quadratic relationship between mean CV of a population and BW of pigs whereby the rate of decrease is smaller as mean pig BW increases from birth to market. Conversely, the rate of increase of SD of a population of pigs is smaller as mean pig BW increases from birth to market.

Effect of the number of parents and their combining ability on the performance of synthetic varieties in tall fescue

2007 ◽  
Vol 58 (11) ◽  
pp. 1100 ◽  
Author(s):  
E. Piano ◽  
P. Annicchiarico ◽  
M. Romani ◽  
L. Pecetti
Keyword(s):  
Inbreeding Depression ◽  
Tall Fescue ◽  
Combining Ability ◽  
Diallel Cross ◽  
Forage Yield ◽  
Yield Response ◽  
Temperature Pattern ◽  
Synthetic Varieties ◽  
Yield Values ◽  
Yield Responses

Finding the optimal parent number for synthetic varieties has a crucial importance in forage breeding. The objective of this work was exploring this number for Mediterranean tall fescue selected for forage yield. The general (GCA) and specific (SCA) combining ability of parents, and their effects on the performance and the inbreeding depression of synthetics, were also assessed. The full-sib families from the diallel cross of 20 genotypes chosen from well performing populations were evaluated for fresh biomass over 13 harvests in Sanluri (Sardinia, Italy). The Syn 1 and Syn 2 of 15 synthetics varying in parent number (4, 8, 12, 16 or 20) and, within same number, in mean GCA of parents were evaluated for dry matter yield over 11 harvests in Lodi (northern Italy) in a greenhouse simulating the temperature pattern of a Mediterranean environment. The yield responses of Syn 2 synthetics with 2 to 20 parents with highest mean GCA were predicted from yield values of S1 and F1 progenies, also evaluated in Lodi. The variance of GCA effects was almost 2-fold larger than that of SCA effects. The observed vigour loss from Syn 1 to Syn 2 of the 4-parent synthetics (−6%) tended to be greater than those of higher parent number groups. The 4-parent synthetics with larger SCA effects tended to greater inbreeding depression. The comparison among synthetics with different parent number and highest GCA of their parents indicated the superiority of the 4-parent synthetic over any other in both generations (P < 0.05). The predicted yield response was maximised by the 3-parent synthetic. The results and other considerations suggest adoption of 4- to 6-parent synthetics.

Long-term effect of cropping system and nitrogen and phosphorus fertilizer on production and nitrogen economy of grain crops in a Brown Chernozem

2005 ◽  
Vol 85 (1) ◽  
pp. 81-93 ◽  
Author(s):  
C. A. Campbell ◽  
R. P. Zentner ◽  
F. Selles ◽  
P. G. Jefferson ◽  
B. G. McConkey ◽  
...  
Keyword(s):  
Water Use ◽  
Environmental Sustainability ◽  
Crop Production ◽  
N Uptake ◽  
Yield Response ◽  
Average Response ◽  
Nitrogen And Phosphorus ◽  
N Yield ◽  
P Fertilizer

Assessment of the long-term impact of fertilizers and other management factors on crop production and environmental sustainability of cropping systems in the semi-arid Canadian prairies is needed. This paper discusses the long-term influence of N and P fertilizers on crop production, N uptake and water use of hard red spring wheat (Triticum aestivum L.), and the effect of the preceding crop type [flax (Linum usitatissimum L.) and fall rye (Secale cereale L.)] on wheat grown on a medium-textured, Orthic Brown Chernozem at Swift Current, Saskatchewan. We analysed 36 yr of results (1967–2002) from eight crop rotation-fertility treatments: viz., fallow-wheat receiving N and P (F-W, N + P), three F-W-W treatments fertilized with (i) N + P, (ii) P only, and (iii) N only; two other 3-yr mixed rotations with N + P (i) F-flax-W (F-Flx-W) and (ii) F-fall rye-W (F-Rye-W); and two continuous wheat rotations (Cont W), one receiving N + P and the other only P. Growing season weather conditions during the 36-yr period were near the long-term mean, but the first 22 yr were generally drier than normal while the last 14 yr (1989–2002) had average to above-average growing conditions. This was partly responsible for grain and N yield being greater in the latter period than in the first 22 yr. The 36-yr average response of wheat grown on fallow to P fertilizer was 339 kg ha-1, while the response to N fertilizer over this period was only 123 kg ha-1. The 36-yr average response of wheat grown on stubble to N was 344 kg ha-1 for F-W-(W) and 393 kg ha-1 for Cont W. Neither flax nor fall rye influenced the yield response of the following wheat crops. Annualized grain production for F-W (N + P), F-W-W (+ N) and F-W-W (+ P) rotations were similar (1130 kg ha-1 yr-1); this was about 15% lower than for F-W-W (N + P), 40% lower than for Cont W (N + P), and 5% lower than for Cont W (+ P). Annualized aboveground N yield for Cont W (N + P) was 57% higher than for Cont W (+ P). Regressions were developed relating straw to grain yields for wheat, flax and fall rye. The amount of NO3-N left in the soil was directly related to amount of N applied and inversely to N removed in the crop. Thus, F-(W)-W (+ N) left about 28% more NO3-N in the rooting zone than F-(W)-W (N + P), while F-W-(W) (N + P) left 20% more than F-W-(W) (+ P), and Cont W (N + P) left 39% more than Cont W (+ P). F-Rye-W (N + P) left much less NO3-N in the soil than any other fallow-containing system and similar amounts to Cont W (N + P). Key words: Yields, grain protein, N and P fertilizer, straw/grain regressions, water use, soil nitrate

Nitrogen, Phosphorus and Water Contents During Grain Development and Maturation in Wheat

1977 ◽  
Vol 4 (5) ◽  
pp. 799 ◽  
Author(s):  
I Sofield ◽  
IF Wardlaw ◽  
LT Evans ◽  
SY Zee
Keyword(s):  
Grain Growth ◽  
Dry Matter ◽  
Nitrogen Concentration ◽  
Growth Period ◽  
Calcium Content ◽  
Dry Weight ◽  
Water Entry ◽  
Grain Development ◽  
Nitrogen And Phosphorus ◽  
Steady Rate

Plants of five cultivars of wheat were grown under controlled-environmental conditions in order to analyse the effect of cultivar and of temperature and illuminance after anthesis on the accumulation of nitrogen and phosphorus by grains in relation to dry matter. The water relations of the grain during maturation were also examined, using calcium content as an index of water entry. The nitrogen and phosphorus contents of grains increased linearly throughout the grain growth period. The percentage of nitrogen and phosphorus in grains fell sharply during the first few days after anthesis but rose progressively thereafter. The higher the temperature, and the lower the illuminance, the higher was the percentage of nitrogen in the grain of all cultivars. Such conditions also reduce final grain size, but their effects on nitrogen concentration in the grain were apparent early in grain development. No evidence was found of a flush of nitrogen or phosphorus into the grain late in its development. Water entry into the grain continued at a steady rate until maximum grain dry weight was reached, then ceased suddenly. No evidence was found of an increased rate of water loss by the grain at that stage, and the rapid fall in water content at the cessation of grain growth may have been due to blockage of the chalazal zone of entry into the grain by the deposition of lipids. Accumulation of dry matter, nitrogen and phosphorus and entry of water into the grain all ceased at the time of lipid deposition in the chalazal zone.

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