Impact of Timing and Method of Virus Inoculation on the Severity of Wheat Streak Mosaic Disease

Wheat streak mosaic virus (WSMV), transmitted by the wheat curl mite Aceria tosichella, frequently causes significant yield loss in winter wheat throughout the Great Plains of the United States. A field study was conducted in the 2013–14 and 2014–15 growing seasons to compare the impact of timing of WSMV inoculation (early fall, late fall, or early spring) and method of inoculation (mite or mechanical) on susceptibility of winter wheat cultivars Mace (resistant) and Overland (susceptible). Relative chlorophyll content, WSMV incidence, and yield components were determined. The greatest WSMV infection occurred for Overland, with the early fall inoculations resulting in the highest WSMV infection rate (up to 97%) and the greatest yield reductions relative to the control (up to 94%). In contrast, inoculation of Mace resulted in low WSMV incidence (1 to 28.3%). The findings from this study indicate that both method of inoculation and wheat cultivar influenced severity of wheat streak mosaic; however, timing of inoculation also had a dramatic influence on disease. In addition, mite inoculation provided much more consistent infection rates and is considered a more realistic method of inoculation to measure disease impact on wheat cultivars.

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Physiologic Specialization of Puccinia triticina on Wheat in the United States in 2016

Plant Disease ◽

10.1094/pdis-11-17-1701-sr ◽

2018 ◽

Vol 102 (6) ◽

pp. 1066-1071 ◽

Cited By ~ 15

Author(s):

J. A. Kolmer ◽

M. E. Hughes

Keyword(s):

United States ◽

Winter Wheat ◽

Leaf Rust ◽

Great Plains ◽

Puccinia Triticina ◽

The United States ◽

Wheat Cultivars ◽

Soft Red Winter Wheat ◽

Winter Wheat Cultivars ◽

Red Winter Wheat

Leaves of wheat infected with the leaf rust fungus Puccinia triticina were obtained from farm fields and breeding plots at experimental stations in the Great Plains, Ohio River Valley, and southeastern states in 2016 in order to identify virulence phenotypes prevalent in the United States in different wheat-growing regions. In total, 496 single uredinial isolates derived from the leaf rust collections were tested for virulence to 20 lines of Thatcher wheat that differ for single leaf rust resistance genes. In total, 71 virulence phenotypes were described in the United States in 2016. The three most common virulence phenotypes across the United States were MBTNB, MBDSD, and TNBJJ. Phenotype MBTNB is virulent to Lr11, and was most common in the soft red winter wheat region of the southeastern states and Ohio Valley. Phenotype MBDSD is virulent to Lr17 and Lr39, and was most common in the hard red winter wheat area of the southern Great Plains. Phenotype TNBJJ is virulent to Lr24 and Lr39, which are present in the hard red winter wheat cultivars. The P. triticina population in the United States was characterized by two major regional groups of virulence phenotypes in the Great Plains region where hard red winter and spring wheat cultivars are grown, and in the southeastern states and Ohio Valley region where soft red winter wheat cultivars are grown. Isolates from New York State differed the most for virulence compared with the other two major regions.

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Imazamox Rates, Timings, and Adjuvants Affect Imidazolinone-Tolerant Winter Wheat Cultivars

Weed Technology ◽

10.1614/wt-04-148r1.1 ◽

2005 ◽

Vol 19 (3) ◽

pp. 599-607 ◽

Cited By ~ 14

Author(s):

John C. Frihauf ◽

Stephen D. Miller ◽

Craig M. Alford

Keyword(s):

Winter Wheat ◽

Field Experiments ◽

Nitrate Solution ◽

Wheat Yield ◽

Early Spring ◽

Growing Seasons ◽

Ammonium Nitrate Solution ◽

Severity Of Injury ◽

Winter Wheat Cultivars ◽

Early Fall

Irrigated field experiments were conducted near Torrington, WY, during the 2001 to 2002 (year 1) and 2002 to 2003 (year 2) winter wheat growing seasons to evaluate cultivar response to different imazamox rates, adjuvants, and application timings. Five cultivars were treated postemergence in the early fall (EF), late fall (LF), or early spring (ES) with imazamox at 54 or 108 g ai/ha, including either nonionic surfactant (NIS) at 0.25% or methylated seed oil (MSO) at 1% (v/v) as adjuvants. A 28% urea ammonium nitrate solution at 1% (v/v) was included with all treatments. Spring injury was more severe in year 1 than year 2. Severe spring injury on ‘AP502 CL’, ‘Above’, ‘IMI-Fidel’, ‘IMI-Jagger’, and ‘IMI-Madsen’ was linked to fall application of 108 g/ha imazamox with MSO. Imazamox applied at 108 g/ha plus MSO applied in the fall consistently injured all cultivars more than the same rate with NIS and 54 g/ha imazamox regardless of adjuvant and timing, although severity of injury in the experiments differed between EF and LF timings in years 1 and 2, respectively. Correlation analysis supports injury reduced reproductive tillers per meter of row and wheat yields and increased the number of seeds per spike in year 1. The reduction of reproductive tillers per meter of row in year 1 was likely the result of severe injury caused by 108 g/ha imazamox applied in the EF coupled with little snow cover to protect against cold winter temperatures. Wheat yield in year 1 was reduced by 108 g/ha imazamox applied in the early fall; however, imazamox applied at 54 g/ha with either adjuvant in EF, LF, or ES were safe. Yield parameters and wheat yields in year 2 were not affected by imazamox rate, adjuvant, timing, or interactions of these factors.

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Physiologic Specialization of Puccinia triticina on Wheat in the United States in 2015

Plant Disease ◽

10.1094/pdis-02-17-0200-sr ◽

2017 ◽

Vol 101 (12) ◽

pp. 1968-1973 ◽

Cited By ~ 5

Author(s):

J. A Kolmer ◽

M. E. Hughes

Keyword(s):

United States ◽

Winter Wheat ◽

Leaf Rust ◽

Great Plains ◽

Puccinia Triticina ◽

The United States ◽

Wheat Cultivars ◽

Soft Red Winter Wheat ◽

Winter Wheat Cultivars ◽

Red Winter Wheat

Leaves of wheat infected with the leaf rust fungus, Puccinia triticina, were obtained from farm fields and breeding plots at experimental stations in the Great Plains, Ohio River Valley, and southeastern states in 2015 in order to identify virulence phenotypes prevalent in the United States in different wheat growing regions. A total of 526 single uredinial isolates derived from the leaf rust collections were tested for virulence to 20 lines of Thatcher wheat that differ for single leaf rust resistance genes. A total of 60 virulence phenotypes were described in the United States in 2015. The three most common virulence phenotypes across the United States were MBDSD, MBTNB, and TBBGS. Phenotype MBDSD is virulent to Lr17, Lr37, and Lr39, and was most common in the hard red winter wheat area of the southern Great Plains. Phenotype MBTNB is virulent to Lr11, and was most common in the soft red winter wheat region of the southeastern states and Ohio Valley. Phenotype TBBGS is virulent to Lr39, which is present in the hard red winter wheat cultivars, and Lr21, which is present in the hard red spring wheat cultivars. The P. triticina population in the United States was characterized by two major regional groups of virulence phenotypes in the Great Plains region where hard red winter and spring wheat cultivars are grown, and in the southeastern states and Ohio Valley region where soft red winter wheat cultivars are grown.

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Estimating Yield Losses Due to Barley Yellow Dwarf on Winter Wheat in Kansas Using Disease Phenotypic Data

Plant Health Progress ◽

10.1094/php-rs-14-0039 ◽

2015 ◽

Vol 16 (1) ◽

pp. 1-6 ◽

Cited By ~ 9

Author(s):

Genna M. Gaunce ◽

William W. Bockus

Keyword(s):

Winter Wheat ◽

Yield Loss ◽

Disease Incidence ◽

Relative Yield ◽

Yellow Dwarf ◽

Wheat Cultivars ◽

Grain Yields ◽

Barley Yellow Dwarf ◽

Winter Wheat Cultivars ◽

The Impact

Barley yellow dwarf (BYD) is one of the most important wheat diseases in the state of Kansas. Despite the development of cultivars with improved resistance to BYD, little is known about the impact that this resistance has on yield loss from the disease. The intent of this research was to estimate yield loss in winter wheat cultivars in Kansas due to BYD and quantify the reduction in losses associated with resistant cultivars. During seven years, BYD incidence was visually assessed on numerous winter wheat cultivars in replicated field nurseries. When grain yields were regressed against BYD incidence scores, negative linear relationships significantly fit the data for each year and for the combined dataset covering all seven years. The models showed that, depending upon the year, 19–48% (average 33%) of the relative yields was explained by BYD incidence. For the combined dataset, 29% of the relative yield was explained by BYD incidence. The models indicated that cultivars showing the highest disease incidence that year had 25–86% (average 49%) lower yield than a hypothetical cultivar that showed zero incidence. Using the models, the moderate level of resistance in the cultivar Everest was calculated to reduce yield loss from BYD by about 73%. Therefore, utilizing visual BYD symptom evaluations in Kansas coupled with grain yields is useful to estimate yield loss from the disease. Accepted for publication 1 December 2014. Published 9 January 2015.

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Pre-anthesis development of winter wheat and barley and relationships with grain yield

Plant Soil and Environment ◽

10.17221/202/2018-pse ◽

2018 ◽

Vol 64 (No. 7) ◽

pp. 310-316 ◽

Cited By ~ 1

Author(s):

Mirosavljevic Milan ◽

Momcolovic Vojislava ◽

Maksimovic Ivana ◽

Putnik-Delic Marina ◽

Pržulj Novo ◽

...

Keyword(s):

Winter Wheat ◽

Grain Yield ◽

Sowing Date ◽

Wheat Cultivars ◽

Growing Seasons ◽

Sowing Dates ◽

Winter Wheat Cultivars ◽

Leaf Appearance ◽

Relationship Of ◽

The Relationship

The aim of this study was to improve understanding of (1) the effect of genotypic and environmental factors on pre-anthesis development and leaf appearance traits of barley and wheat; (2) the relationship of these factors with grain yield, and (3) the differences between these two crops across different environments/sowing dates. Therefore, trials with six two-row winter barley and six winter wheat cultivars were carried out in two successive growing seasons on four sowing dates. Our study showed that the observed traits varied between species, cultivars and sowing dates. In both growing seasons, biomass at anthesis and grain yield declined almost linearly by delaying the sowing date. There was no clear advantage in grain yield of wheat over barley under conditions of later sowing dates. Generally, barley produced more leaf and had shorter phyllochron than wheat. Both wheat and barley showed a similar relationship between grain yield and different pre-anthesis traits.

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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 A Rht GENE CONDITIONING THE SEMIDWARF CHARACTER ON WINTERHARDINESS IN WINTER WHEAT (Triticum aestivum L. em Thell)

Canadian Journal of Plant Science ◽

10.4141/cjps88-040 ◽

1988 ◽

Vol 68 (2) ◽

pp. 301-309 ◽

Cited By ~ 3

Author(s):

D. J. GILLILAND ◽

D. B. FOWLER

Keyword(s):

Triticum Aestivum ◽

Gibberellic Acid ◽

Winter Wheat ◽

Great Plains ◽

Cold Hardiness ◽

Triticum Aestivum L ◽

Breeding Strategy ◽

Sensitivity Analyses ◽

Wheat Cultivars ◽

Winter Wheat Cultivars

In the northern part of the North American Great Plains, the level of cultivar winter-hardiness required for winter wheat (Triticum aestivum L.) production is extremely high. Presently, available winter wheat cultivars with adequate winterhardiness are tall and, under favourable growing conditions, crop lodging and excessive amounts of straw can present serious production problems. Consequently, cultivars with short, stiff straw and a high harvest index would be desirable for high production areas within this region. However, semidwarf cultivars with superior winterhardiness have not yet been developed. In this study, six GA-insensitive (Rht) semidwarf parents with poor to moderate winterhardiness were crossed with three GA-sensitive (rht) tall parents possessing good winterhardiness to produce 20 different single, three-way and double crosses. These crosses were evaluated to determine if the GA-insensitive character could be combined with a high level of winterhardiness in winter wheat. Gibberellic acid (GA) sensitivity analyses of F2 seedlings established that a single GA-insensitive gene was involved in each cross. F2-derived F3 and F3-derived F4 lines were assessed for GA-sensitivity and winterhardiness levels were determined from field survival at several locations in Saskatchewan, Canada. Winter survival of homozygous GA-sensitive and GA-insensitive lines were similar in both generations. Lines with winterhardiness levels similar to those of the three tall parent cultivars were recovered in all GA-response classes. The absence of a meaningful pleiotropic effect of Rht genes on winterhardiness indicates that the reason semidwarf cultivars with superior winterhardiness levels have not been developed is due to the lack of a concentrated breeding effort to combine the two characters. A breeding strategy for the production of adapted winterhardy semidwarf winter wheat cultivars is discussed. The influence of endogenous gibberellin levels on cold hardiness in winter wheat is also considered.Key words: Cold hardiness, field survival, Triticum aestivum L, semidwarf, Gibberellic acid

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Physiologic Specialization of Puccinia triticina on Wheat in the United States in 2012

Plant Disease ◽

10.1094/pdis-12-13-1267-sr ◽

2014 ◽

Vol 98 (8) ◽

pp. 1145-1150 ◽

Cited By ~ 16

Author(s):

J. A Kolmer ◽

M. E. Hughes

Keyword(s):

United States ◽

Winter Wheat ◽

Leaf Rust ◽

Great Plains ◽

Puccinia Triticina ◽

The United States ◽

Wheat Cultivars ◽

Soft Red Winter Wheat ◽

Hard Red Winter Wheat ◽

Red Winter Wheat

Collections of Puccinia triticina were obtained from rust-infected leaves provided by cooperators throughout the United States and from wheat fields and breeding plots by United States Department of Agriculture–Agricultural Research Service personnel and cooperators in the Great Plains, Ohio River Valley, southeastern states, and Washington State and Idaho in order to determine the virulence of the wheat leaf rust population in 2012. Single uredinial isolates (501 in total) were derived from the collections and tested for virulence phenotype on 20 lines of ‘Thatcher’ wheat that are near-isogenic for leaf rust resistance genes. In 2012, 74 virulence phenotypes were described in the United States. Virulence phenotypes TNBGJ, TCRKG, and MBTNB were the three most common phenotypes. Phenotype TNBGJ is virulent to Lr39/41 and was widely distributed throughout the hard red winter wheat region of the Great Plains. Phenotype TCRKG is virulent to Lr11, Lr18, and Lr26 and was found mostly in the soft red winter wheat region in the eastern United States. Phenotype MBTNB is virulent to Lr11 and was also found mostly in the soft red winter wheat region. The frequency of isolates with virulence to Lr39/41, which is present in many hard red winter wheat cultivars in the Great Plains region, continued to increase. Isolates with virulence to Lr21, which is present in many hard red spring wheat cultivars, also continued to increase in frequency in the northern Great Plains region.

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Effect of Fluoride on Germination, Early Growth and Antioxidant Enzymes Activity of Three Winter Wheat (Triticum aestivum L.) Cultivars

Applied Sciences ◽

10.3390/app10196971 ◽

2020 ◽

Vol 10 (19) ◽

pp. 6971

Author(s):

Justyna Pelc ◽

Martyna Śnioszek ◽

Jacek Wróbel ◽

Arkadiusz Telesiński

Keyword(s):

Antioxidant Enzymes ◽

Winter Wheat ◽

Root Growth ◽

Wheat Cultivar ◽

Fluoride Concentration ◽

Triticum Aestivum L ◽

Wheat Cultivars ◽

Growth Phases ◽

Winter Wheat Cultivars ◽

The Impact

This paper assesses the impact of sodium fluoride on the morphological parameters and activity of catalase and peroxidase during the germination and root growth phases of three winter wheat cultivars: Tobak, Dalewar, and Arkadia. During examination, the seeds were placed on plastic Petri dishes with an NaF solution at concentrations of 0 (control), 2.5, 5.0, 8.0, and 10.0 mmol dm−3. The obtained results have shown a decrease in germination, inhibition of root growth, and inhibition of catalase activity, both in the embryos and roots of all tested winter wheat cultivars. The observed effects have been strengthened with the increase of the fluoride concentration. However, the effect of NaF on the peroxidase activity has been dependent on the wheat cultivar. It is difficult to state unequivocally which of the tested winter wheat cultivars has been characterized by the highest sensitivity to fluoride. An η2 analysis has confirmed that the NaF concentration has a greater effect than the winter wheat cultivar on the activity of the determined antioxidant enzymes.

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Integrated Management of Stripe Rust and Overwintering of Puccinia striiformis f. sp. tritici in Wisconsin

Plant Health Progress ◽

10.1094/php-04-20-0027-rs ◽

2020 ◽

Vol 21 (3) ◽

pp. 205-211

Author(s):

Brian D. Mueller ◽

Carol L. Groves ◽

Shawn P. Conley ◽

Scott A. Chapman ◽

Mehdi Kabbage ◽

...

Keyword(s):

Winter Wheat ◽

Stripe Rust ◽

Management Practices ◽

Puccinia Striiformis ◽

Integrated Management ◽

The United States ◽

Growth Stages ◽

Soft Red Winter Wheat ◽

Winter Wheat Cultivars ◽

The Impact

Puccinia striiformis f. sp. tritici (Pst) is the causal agent of stripe rust and is one of the most problematic pathogens of winter and spring wheat in the United States. Planting resistant cultivars and applying foliar fungicides are common management practices to control this pathogen. In this 2-year study, two fungicides applied at three growth stages were tested on three soft red winter wheat cultivars varying in levels of resistance to stripe rust. Both fungicides (prothioconazole + tebuconazole and pyraclostrobin) applied at Feekes 8 and 10 reduced disease index and increased yield compared with the nontreated control in susceptible (‘Pro Seed 420’) and moderately susceptible (‘Kaskaskia’) cultivars. The highly resistant cultivar (‘Pro Seed 380’) had the greatest yields, and fungicide treatments had no effect on disease levels or yield. In an accompanying study, Pst was found to survive over the 2016 to 2017 winter on the susceptible cultivar Pro Seed 420. This study confirmed that resistance and properly timed fungicide applications play a crucial role in managing stripe rust on winter wheat. This study also demonstrated that Pst can overwinter in Wisconsin, and the impact of this occurrence should be examined further.

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