Rapid Estimation of Potentially Mineralizable N in Early Spring Following Fall Biosolids Applications to Winter Wheat

Effects of rotation length, fallow-substitute crops, and N and P fertilizer on some physical and biological properties of a Brown Chernozemic loam in southwestern Saskatchewan were determined over a period of 16 yr. After 12 yr, the erodible fraction in the top 15 cm of soil (i.e., < 0.84 mm) was inversely related to trash conserved and thus rotation length. Soil organic N (in the top 15 cm) increased from 0.18 to 0.20% in continuous-type rotations receiving an average 32 kg N∙ha−1∙yr−1 and adequate P, but it did not increase in continuous wheat receiving P only, nor in fallow rotations, except the one that included fall rye (Secale cereale L.). This N increase was credited partly to fertilizer and partly to more efficient use and cycling of subsoil NO3-N via plant roots and crop residues. After 10 yr, well-fertilized continuous-type rotations had a 13% greater C content than fallow rotations and continuous wheat receiving only P. In the top 7.5 cm of soil under the four rotations examined in detail, bacterial numbers were lowest in fallow-wheat, intermediate in fallow-wheat-wheat, higher in continuous wheat receiving N and P, and highest in continuous wheat receiving only P. Similarly, microbial biomass C in these four rotations was 180, 226, 217 and 357 kg∙ha−1; biomass N was 52, 65, 54 and 72 kg∙ha−1; and biomass C/N ratios were 3.4, 3.5, 4.1 and 5.1, respectively. Differences in biomass C/N, respiration rates and numbers of bacteria, actinomycetes and yeasts indicated both quantitative and qualitative microbial changes and reflected increasing rotation length and differences in fertility. Potentially mineralizable N (No) was 192 kg∙ha−1 for adequately fertilized continuous wheat, and exceeded No in fallow-wheat by 45%, in fallow-wheat-wheat by 17% and in continuous wheat receiving only P by 25%. The latter rotation contained a large but fairly inactive microbial population. We concluded that land degradation caused by frequent summerfallowing can be arrested and the decline in amount and quality of organic matter reversed by use of available agronomic technology. Key words: Microbial biomass, microbial activity, potentially mineralizable N, respiration, soil erodibility

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Cytokinins and abscisic acid in hardening winter wheat

Canadian Journal of Botany ◽

10.1139/b90-205 ◽

1990 ◽

Vol 68 (7) ◽

pp. 1597-1601 ◽

Cited By ~ 11

Author(s):

John S. Taylor ◽

Munjeet K. Bhalla ◽

J. Mason Robertson ◽

Lu J. Piening

Keyword(s):

Triticum Aestivum ◽

Abscisic Acid ◽

Winter Wheat ◽

Leaf Tissue ◽

Triticum Aestivum L ◽

Early Spring ◽

Growth Chamber ◽

Late Winter ◽

Sequence Of Events ◽

Freeze Dried

During overwintering in a northern climate, winter wheat goes through a hardening process, followed by dehardening in late winter – early spring. This sequence of events may be partially controlled by changes in endogenous hormone levels. Crowns and leaf tissue from field grown winter wheat (Triticum aestivum L. cv. Norstar) seeded at the beginning of September were collected and freeze-dried at monthly intervals during the winters of 1985–1986 and 1986–1987. Material was also sampled and freeze-dried from seedlings grown in a growth chamber under hardening conditions (21 °C for 2 weeks plus 3 °C for 6 weeks) or nonhardening conditions (3 weeks at 21 °C). The tissues were analysed for cytokinins and abscisic acid. Cytokinin levels, measured with the soybean hypocotyl section assay, declined from October onwards and then rose to a peak in late winter (January and February, winter 1986–1987; February and March, winter 1985–1986), subsequently declining again. Abscisic acid, quantitated as the methyl ester by gas chromatography with an electron capture detector, increased in level from October to December, then decreased to a relatively low level between January and March. Hardened seedlings from the growth chamber contained significantly higher abscisic acid levels and significantly lower cytokinin levels than did the nonhardened seedlings. Key words: abscisic acid, cytokinins, hardening, Triticum aestivum, winter wheat.

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Use of hot KCl-NH4-N to estimate fertilizer N requirements

Canadian Journal of Soil Science ◽

10.4141/s96-106 ◽

1997 ◽

Vol 77 (2) ◽

pp. 161-166 ◽

Cited By ~ 19

Author(s):

C. A. Campbell ◽

Y. W. Jamel ◽

A. Jalil ◽

J. Schoenau

Keyword(s):

N Mineralization ◽

Growth Models ◽

Growing Season ◽

Order Rate Constant ◽

Weather Data ◽

N Availability ◽

Fertilizer N ◽

Available N ◽

Mineralizable N ◽

Potentially Mineralizable N

We need an easy-to-use chemical index for estimating the amount of N that becomes available during the growing season, to improve N use efficiency. This paper discusses how producers may, in future, use crop growth models that incorporate indices of soil N availability, to make more accurate, risk-sensitive estimates of fertilizer N requirements. In a previous study, we developed an equation, using 42 diverse Saskatchewan soils, that related potentially mineralizable N (N0) to NH4N extracted with hot 2 M KCl (X), (i.e., N0 = 37.7 + 7.7X, r2 = 0.78). We also established that the first order rate constant (k) for N mineralization at 35°C is indeed a constant for arable prairie soils (k = 0.067 wk−1). We modified the N submodel of CERES-wheat to include k and N0 (values of N0 were derived from the hot KCl test). With long-term weather data (precipitation and temperature) as input, this model was used to estimate probable N mineralization during a growing season and yield of wheat (grown on fallow or stubble), in response to fertilizer N rates at Swift Current. The model output indicated that the amount of N mineralized in a growing season for wheat on fallow was similar to that for wheat on stubble, as we hypothesized. Further the model indicated that rate of fertilizer N had only minimal effect on N mineralized. We concluded that, despite the importance of knowing the Nmin capability of a soil, it is available water, initial levels of available N and rate of fertilizer N that are the main determinants of yield in this semiarid environment. The theoretical approach we have proposed must be validated under field conditions before it can be adopted for use. Key words: N mineralization, Hot KCl-NH4-N, potentially mineralizable N, CERES-wheat model

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Enhanced nitrogen management strategies for winter wheat production in the Canadian prairies

Canadian Journal of Plant Science ◽

10.1139/cjps-2017-0319 ◽

2018 ◽

Vol 98 (3) ◽

pp. 683-702 ◽

Cited By ~ 4

Author(s):

B.L. Beres ◽

R.J. Graf ◽

R.B. Irvine ◽

J.T. O’Donovan ◽

K.N. Harker ◽

...

Keyword(s):

Winter Wheat ◽

Grain Yield ◽

Nutrient Management ◽

Management Strategies ◽

Maximum Yield ◽

Nitrification Inhibitor ◽

Early Spring ◽

Nitrification Inhibitors ◽

Side Band ◽

Application Method

To address knowledge gaps around enhanced efficiency urea fertilizer efficacy for nitrogen (N) management, a study was designed to improve integrated nutrient management systems for western Canadian winter wheat producers. Three factors were included in Experiment 1: (i) urea type [urea, urea + urease inhibitor—Agrotain®; urea + urease and nitrification inhibitor—SuperU®, polymer-coated urea—Environmentally Smart Nitrogen® (ESN®), and urea ammonium nitrate (UAN)], (ii) application method (side-band vs. spring-broadcast vs. 50% side-band: 50% spring-broadcast), and (iii) cultivar (AC Radiant hard red winter wheat vs. CDC Ptarmigan soft white winter wheat). The Agrotain® and CDC Ptarmigan treatments were removed in Experiment 2 to allow for additional application methods: (i) fall side-band, (ii) 50% side-band — 50% late fall broadcast, (iii) 50% side-band — 50% early spring broadcast, (iv) 50% side-band — 50% mid-spring broadcast, and (v) 50% side-band — 50% late spring broadcast. CDC Ptarmigan produced superior grain yield and N utilization over AC Radiant. Grain yield and protein content were influenced by N form and application method. Split applications of N usually provided the maximum yield and protein, particularly with Agrotain® or SuperU®. An exception to the poor fall-application results was the SuperU® treatments, which produced similar yield to the highest-yielding treatments. The results suggest that split applications of N might be most efficient for yield and protein optimization when combined with an enhanced efficiency urea product, particularly with urease or urease + nitrification inhibitors, and if the majority of N is applied in spring.

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Increasing of wheat grain yield by use of a liquid fertilizer

Advance in Biological Research ◽

10.26855/abr.2020008 ◽

2020 ◽

Vol 1 (1) ◽

pp. 45-49

Author(s):

Tsotne Samadashvili ◽

Gulnari Chkhutiashvili ◽

Mirian Chokheli ◽

Zoia Sikharulidze ◽

Qetevan Nacarishvili

Keyword(s):

Winter Wheat ◽

Grain Yield ◽

Stem Elongation ◽

Organic Fertilizer ◽

Wheat Yield ◽

Mineral Fertilizer ◽

Field Trials ◽

Early Spring ◽

Wheat Grain ◽

Liquid Fertilizer

Wheat is a vital crop in Georgia and in the world. Because of the increase in the rate of population growth, improving the grain yield is the way to meet food demand. Proper crop nutrition plays a vital role in maintaining the world’s food supply. Fertilizer is essential for accomplishing this.One of the most important means for increasing the wheat yield is fertilizer, especially, organic fertilizer. The present research was carried out to study the effects of different doses (150ml, 200ml and 300 ml on ha) of humic organic fertilizer “Ecorost” on yield of winter wheat cultivar “Tbilisuri 15”. The humic liquid fertilizer "Ecorost" is a peat-based organic-mineral fertilizer. The product is active and saturated due to the use of the latest technology and living bacteria found in peat. The field trials were conducted in 2017-2019 at the Experimental Site of Scientific Research Center of Agriculture in Dedopliskharo- arid region (Eastern Georgia).Liquid fertilizer was applied two times: in tillering stage in early spring and two weeks after - in stem elongation stage. Results indicated that the highest wheat grain yield (4t/ha) was achieved when the plants were fertilized with 300 ml on 1 ha ofEcorost. Applications of liquid fertilizer “Ecorost” increased grain yield of winter wheat by 16.2% in comparison with standard nitrogen fertilization. Thus, liquid fertilizer “Ecorost” had a significant effect on wheat grain yield compared to control standard nitrogen fertilizer.

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Effects of Climate Change on Epidemics of Powdery Mildew in Winter Wheat in China

Plant Disease ◽

10.1094/pdis-02-17-0168-re ◽

2017 ◽

Vol 101 (10) ◽

pp. 1753-1760 ◽

Cited By ~ 11

Author(s):

Xiuli Tang ◽

Xueren Cao ◽

Xiangming Xu ◽

Yuying Jiang ◽

Yong Luo ◽

...

Keyword(s):

Climate Change ◽

Relative Humidity ◽

Powdery Mildew ◽

Winter Wheat ◽

Weather Conditions ◽

Early Spring ◽

Long Term Effects ◽

Temperature Changes ◽

Disease Epidemics

Powdery mildew is a highly destructive winter wheat pathogen in China. Since the causative agent is sensitive to changing weather conditions, we analyzed climatic records from regions with previous wheat powdery mildew epidemics (1970 to 2012) and investigated the long-term effects of climate change on the percent acreage (PA) of the disease. Then, using PA and the pathogen’s temperature requirements, we constructed a multiregression model to predict changes in epidemics during the 2020s, 2050s, and 2080s under representative concentration pathways RCP2.6, RCP4.5, and RCP8.5. Mean monthly air temperature increased from 1970 to 2012, whereas hours of sunshine and relative humidity decreased (P < 0.001). Year-to-year temperature changes were negatively associated with those of PA during oversummering and late spring periods of disease epidemics, whereas positive relationships were noted for other periods, and year-to-year changes in relative humidity were correlated with PA changes in the early spring period of disease epidemics (P < 0.001). Our models also predicted that PA would increase less under RCP2.6 (14.43%) than under RCP4.5 (14.51%) by the 2020s but would be higher by the 2050s and 2080s and would increase least under RCP8.5 (14.37% by the 2020s). Powdery mildew will, thus, pose an even greater threat to China’s winter wheat production in the future.

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Adapting the potentially mineralizable N concept for the prediction of fertilizer N requirements

Fertilizer Research ◽

10.1007/bf00750500 ◽

1995 ◽

Vol 42 (1-3) ◽

pp. 61-75 ◽

Cited By ~ 11

Author(s):

C. A. Campbell ◽

Y. W. Jame ◽

O. O. Akinremi ◽

M. L. Cabrera

Keyword(s):

Fertilizer N ◽

Mineralizable N ◽

Potentially Mineralizable N

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Influence of level of a nitric food on efficiency and quality of grain of winter wheat in the conditions of Predkamya of RT

Vestnik of Kazan state agrarin university ◽

10.12737/3828 ◽

2014 ◽

Vol 9 (1) ◽

pp. 91-94

Author(s):

Тагиров ◽

Marsel Tagirov ◽

Газизов ◽

Ilyas Gazizov ◽

Фадеева ◽

...

Keyword(s):

Winter Wheat ◽

Nitrogen Nutrition ◽

Mineral Elements ◽

Early Spring ◽

Nitrogen Fertilizers ◽

Yield Increase ◽

Grain Productivity ◽

Plant Stand ◽

The Republic

Winter wheat productivity and grain quality is largely dependent on the availability of mineral elements of plants throughout the growing season. [2] Early spring fertilization with nitrogen fertilizers contributes to more rapid growth of the root system, further tillering, strengthening of ear shoots development and highest yield increase. Application of fertilizers, containing micronutrients (Akvarin 5), having a complex effect on plants, is perspective in high quality grain production. In this paper, we studied the effect of nitrogen nutrition and trace elements on grain productivity and quality, perspective and zoned species in the Republic of Tatarstan. Spring introduction of nitrogen in the form of ammonium nitrate leads to an increase the density of productive plant stand to 10.0%, crop yield to 20%. Treating the plant by Akvarin5 preparation in tillering period, it increases the density of plant stand of winter wheat on average 2.89%, productivity to 4.3% or 0.21 tons per hectare, compared to one with a nitrogen fertilizing. Akvarin 5 preparation leads to weight rising of 1000 grains more significant at making it in earing - flowering phase, than in the phase of tillering. It also increases the weight of the grain and gluten content. A greater influence on the nature of grain has a nitrogen fertilizer, than treatment by Akvarin 5.

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Effect of plant age on water content in crowns of fall rye and winter wheat cultivars differing in snow mold resistance

Canadian Journal of Plant Science ◽

10.4141/p00-002 ◽

2001 ◽

Vol 81 (3) ◽

pp. 541-550 ◽

Cited By ~ 2

Author(s):

D. A. Gaudet ◽

A. Laroche ◽

B. Puchalski

Keyword(s):

Winter Wheat ◽

Water Content ◽

Developmental State ◽

Early Spring ◽

Plant Age ◽

Wheat Cultivars ◽

Snow Mold ◽

Winter Wheat Cultivars ◽

Controlled Environments ◽

Mold Resistance

Resistance to snow molds in winter wheat increases with plant age, and older plants express higher levels of resistance than young plants. Experiments were conducted to study the effect of plant age on percent crown water content (%CWC) and dry weights in fall rye and winter wheat cultivars grown under controlled environments and in the field at Lethbridge, AB. Under controlled environments, the oldest (6 wk of pre-hardening growth at 20°C) treatments accumulated the greatest dry weights following exposure of plants to 1 to 6 wk hardening conditions at 2°C, compared with younger (1 to 4 wk pre-hardening growth) treatments. Exposure of plants to hardening temperatures had the greatest effect on %CWC values, which decreased, gradually, from 82–89% (4.95–8.67 g H2O g–1 DW) in unhardened treatments to 67–72% (2.05–2.65 g H2O g–1 DW) in plants receiving the 6 wk pre-hardening and 6 wk hardening growth. However, the oldest treatments (4 to 6 wk pre-hardening growth) always exhibited the lowest %CWC values among all hardening treatments. The %CWC in the oldest (6 wk) unhardened plants was also lower ([Formula: see text] = 80.8% or 4.24 g H2O g–1 DW) than in the youngest (1wk) unhardened plants ([Formula: see text] = 91.2% or 11.31 g H2O g–1 DW ), demonstrating that water loss occurs in older plants in the absence of low hardening temperatures. In a field study at Lethbridge during the autumn, winter, and early spring of 1997–1998 and 1998–1999, different seeding dates were employed to obtain plants differing in age and developmental state. The %CWC in early-seeded treatments was lower during the autumn, and remained lower in early spring, compared with later seeded cultivars. The %CWC in crowns was negatively associated with the snow mold resistance rating of a fall rye and five winter wheat cultivars under controlled environment conditions, and among a fall rye and 13 winter wheat cultivars in the field; the highest correlation values in the field were observed from mid-November to mid-March during 1997–1998 (r = –0.84), and 1998–1999 (r = – 0.76). These results indicate that the type of snow mold resistance that increases with plant age is related to the accumulation of crown dry matter and the ability of wheat and rye plants to lose crown water in response to both extended growth at warm temperatures and hardening at low, above freezing temperatures. Key words: Carbohydrates, fructans, low temperature basidiomycete, Coprinus psychromorbidus

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Effect of Application Timing on Winter Wheat Response to Metribuzin

Weed Technology ◽

10.1017/wet.2016.7 ◽

2017 ◽

Vol 31 (1) ◽

pp. 94-99 ◽

Cited By ~ 1

Author(s):

Mark J. VanGessel ◽

Quintin R. Johnson ◽

Barbara A. Scott

Keyword(s):

Winter Wheat ◽

Yield Loss ◽

Early Spring ◽

Growth Stages ◽

Wheat Cultivars ◽

Weed Species ◽

Application Timing ◽

Herbicide Resistant ◽

Stage 4 ◽

Stage 1

Metribuzin will control many problematic weed species in winter wheat in the mid-Atlantic states, including herbicide-resistant biotypes, but it has not been recommended due to crop safety concerns. In a three-year trial, metribuzin was applied at 105 or 210 g ai ha−1to wheat at the PRE, 2-leaf (Feekes stage 1 to 2), early spring (Feekes stage 3 to 4), and late spring (Feekes stage 4 to 6) growth stages using wheat cultivars sensitive to metribuzin. Early spring applications had the least amount of injury, and injury at this timing was transient and yield was not reduced. Yield loss was observed with the other application timings in at least one out of three years. Rainfall shortly after application appears to increase the risk of wheat injury.

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