Influence of wild oat plant density on spring wheat yield

Field experiments were conducted to determine the effect of nitrogen fertilization on competition between wild oat (Avena fatuaL. # AVEFA) and spring wheat (Triticum aestivum‘Anza’). Nitrogen fertilizer treatments were applied over several wild oat-wheat density combinations. Wheat grain yield in wild oat-infested plots generally declined with fertilization while the density of wild oat panicles increased. Apparently, in competition with wheat, wild oat was better able to utilize the added nitrogen and thus gained a competitive advantage over the wheat. The increased competitiveness of wild oat resulted in reduced crop yields. Under the conditions of these experiments, nitrogen fertilization resulted in positive wheat yield response only when the wild oat plant density was below 1.6 percent of the total plant density.

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Efficacy of Fall Incorporated and Non-incorporated Granular Triallate on Wild Oat (Avena fatua) and Wheat (Triticum aestivum)

Weed Technology ◽

10.1017/s0890037x00039762 ◽

1994 ◽

Vol 8 (3) ◽

pp. 607-611 ◽

Cited By ~ 2

Author(s):

Kenneth J. Kirkland

Keyword(s):

Triticum Aestivum ◽

Spring Wheat ◽

Wheat Yield ◽

Subsequent Development ◽

Avena Fatua ◽

Wild Oat ◽

Fresh Weight ◽

West Central ◽

Wheat Stubble ◽

Incorporation Method

The influence of incorporation vs no incorporation on the efficacy of granular triallate applied in mid-October at 1400 and 1700 g ai/ha to control wild oat was evaluated in spring wheat in west central Saskatchewan over a 7-yr period. All fall-applied triallate reduced wild oat panicles and fresh weight, and increased yield compared to untreated checks. With applications in standing wheat stubble there was no difference in wild oat control from incorporation versus no incorporation. All triallate treatments reduced wild oat panicles and fresh weight by over 95%, and resulted in wheat yield increases ranging from 29 to 67%. In tilled fallow, incorporated granules provided better wild oat control than when there was no incorporation. Wheat yield increases ranged from 50 to 85% for triallate treatments with yield for incorporated triallate approximately 15% greater than non-incorporated. The rate of triallate did not affect the level of wild oat control achieved with either incorporation method. In separate tolerance studies triallate incorporation method did not affect spring wheat emergence or subsequent development.

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Spring Wheat (Triticum aestivum) Growth and Yield as Influenced by Duration of Wild Oat (Avena fatua) Competition

Weed Technology ◽

10.1017/s0890037x00037945 ◽

1993 ◽

Vol 7 (4) ◽

pp. 890-893 ◽

Cited By ~ 11

Author(s):

Kenneth J. Kirkland

Keyword(s):

Triticum Aestivum ◽

Spring Wheat ◽

Wheat Yield ◽

Avena Fatua ◽

Growth And Yield ◽

Wild Oat ◽

Fresh Weight ◽

Leaf Stage ◽

Removal Experiments

The effect of duration of wild oat competition on spring wheat yield and growth was determined in time-of-removal experiments conducted over a three year study period in Saskatchewan, Canada. Failure to remove wild oat reduced wheat yield 28 and 39% at wild oat populations of 64 and 188 plants per m2, respectively. Wheat yield was not reduced by wild oat densities of 64 or 118 plants per m2until the six- and seven-leaf stage of wild oat, respectively. Removing wild oat at 64 plants per m2before the seven-leaf stage and 118 plants per m2before the five-leaf stage did not increase wheat culm or fresh weight production.

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CONTROL OF WILD OAT WITH TRIALLATE IN A SPRING WHEAT CONSERVATION TILLAGE SYSTEM

Canadian Journal of Plant Science ◽

10.4141/cjps86-026 ◽

1986 ◽

Vol 66 (1) ◽

pp. 181-184 ◽

Cited By ~ 1

Author(s):

S. J. CARLSON ◽

L. A. MORROW

Keyword(s):

Triticum Aestivum ◽

Spring Wheat ◽

Conservation Tillage ◽

Wheat Yield ◽

Triticum Aestivum L ◽

Avena Fatua ◽

Wild Oat ◽

Minimum Tillage ◽

Tillage System

Triallate granules were applied at 2.8 kg/ha without incorporation either immediately before or after planting into standing spring wheat (Triticum aestivum L. ’Fielder’ and ’Dirkwin’) stubble. The triallate granules controlled wild oat (Avena fatua L.), and resulted in increased spring wheat yield. Difenzoquat or diclofop-methyl application also increased wheat yields.Key words: Triallate, oat (wild), conservation tillage, minimum tillage, wheat (spring)

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Frequency of post-emergence harrowing effects wild oat control and spring wheat yield

Canadian Journal of Plant Science ◽

10.4141/cjps95-026 ◽

1995 ◽

Vol 75 (1) ◽

pp. 163-165 ◽

Cited By ~ 9

Author(s):

Kenneth J. Kirkland

Keyword(s):

Spring Wheat ◽

Wheat Yield ◽

Triticum Aestivum L ◽

Organic Production ◽

Cultural Control ◽

Wild Oat ◽

Fresh Weight ◽

Wild Oats ◽

Alternative Weed Control ◽

The One

Crops grown by organic producers or others choosing not to use herbicides require alternative weed control methods. In a 3-yr study at Scott, Saskatchewan, several harrowing frequencies were applied to emerged wild oats infesting spring wheat. Two passes with diamond tooth harrows at the one- to two-leaf stage of wild oats reduced panicle density and fresh weight in 2 of 3 yr. Multiple harrowings reduced wheat culms, fresh weight, and yield in 2 of the 3 yr. In 1992, four harrowings reduced wheat culms and yield, but had no effect on wild oat. In 1993, two harrowings reduced wild oat panicles and fresh weight, but had no effect on wheat culms and fresh weight, suggesting that moisture conditions at and immediately following harrowing have a differential effect on the ability of the two species to recover. Key words:Avena fatua L., Triticum aestivum L., cultural control, organic production

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Spring wheat seed size and seeding rate effects on yield loss due to wild oat (Avena fatua) interference

Weed Science ◽

10.1614/ws-03-007r1 ◽

2004 ◽

Vol 52 (1) ◽

pp. 133-141 ◽

Cited By ~ 34

Author(s):

Robert N. Stougaard ◽

Qingwu Xue

Keyword(s):

Grain Yield ◽

Seed Size ◽

Spring Wheat ◽

Plant Density ◽

Cropping System ◽

Wild Oat ◽

Wheat Seed ◽

Seeding Rate ◽

Cereal Grain ◽

Rate Effects

The development of competitive cropping systems could minimize the negative effects of wild oat competition on cereal grain yield, and in the process, help augment herbicide use. A 3-yr field experiment was conducted at Kalispell, MT, to investigate the effects of spring wheat seed size and seeding rate on wheat spike production, biomass, and grain yield under a range of wild oat densities. Wheat plant density, spikes, biomass, and yield all increased as seed size and seeding rates increased. Averaged across all other factors, the use of higher seeding rates and larger seed sizes improved yields by 12 and 18%, respectively. Accordingly, grain yield was more highly correlated with seed size than with seeding rate effects. However, the combined use of both tactics resulted in a more competitive cropping system, improving grain yields by 30%. Seeding rate effects were related to spike production, whereas seed size effects were related to biomass production. As such, plants derived from large seed appear to have greater vigor and are able to acquire a larger share of plant growth factors relative to plants derived from small seed.

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Spring wheat yield response to variable seeding rates in organic farming systems at different fertility regimes

Canadian Journal of Plant Science ◽

10.4141/cjps06051 ◽

2008 ◽

Vol 88 (1) ◽

pp. 43-52 ◽

Cited By ~ 6

Author(s):

R. L. Beavers ◽

A. M. Hammermeister ◽

B. Frick ◽

T. Astatkie ◽

R. C. Martin

Keyword(s):

Spring Wheat ◽

Plant Density ◽

Wheat Yield ◽

Organic Production ◽

Fertility Treatment ◽

Yield Response ◽

High Fertility ◽

Seeding Rate ◽

Crop Density ◽

Plot Experiment

Seeding rates in organic systems should balance a crop’s competitive ability while maintaining grain yield and quality. A 2-yr study assessed the response of spring wheat (Triticum aestivum L.) to variable seeding rates (1 × conventionally recommended rate, 1.25 ×, 1.5 × and 2 × ) in a plot experiment in Nova Scotia and on organic farms across Canada. The plot experiment was a two-factor factorial assessing seeding rate and fertility. For the Canada-wide experiment, the four seeding rates were completely randomized on each farm. Wheat yield was highest at the 2 × seeding rate in 2003, but average crop emergence across all treatment combinations was only 56%. In 2004, crop emergence was 76% and the 1.25 ×, 1.5 × and 2 × seeding rates had greater yield than the 1 × rate. Seeding rate affected plant density and heads per square metre, but no differences were observed among rates for kernels per head or thousand kernel weight. Grain protein content was similar among seeding rates and was increased by the high fertility treatment. On farms, a 1.25 × seeding rate was sufficient to maximize yield when averaged across all sites. Increasing seeding rate by at least 1.25 × the conventionally recommended rate appears to be an appropriate management practice for organic production. Key words: wheat (spring), seeding rate, crop density, organic agriculture

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Wild Oat (Avena fatua) Competition with Spring Wheat: Plant Density Effects

Weed Science ◽

10.1017/s0043174500082059 ◽

1985 ◽

Vol 33 (2) ◽

pp. 176-181 ◽

Cited By ~ 68

Author(s):

Harry L. Carlson ◽

James E. Hill

Keyword(s):

Grain Yield ◽

Regression Models ◽

Field Experiments ◽

Plant Density ◽

Wheat Yield ◽

Wheat Plant ◽

Avena Fatua ◽

Wild Oat ◽

Plant Densities ◽

Crop Stand

Field experiments were conducted to measure the grain yield of wheat (Triticum aestivumL. ‘ANZA’) at various wild oat (Avena fatuaL. ♯ AVEFA) and wheat plant densities. Wheat yield declined as wild oat plant density increased. Wheat yield increased in wild oat-infested plots as wheat plant density increased. Regression models were developed to describe the combined effect of wheat and wild oat plant densities on wheat grain yield. Wheat yields were best described by a nonlinear regression model using the relative density of wild oat in the weed-crop stand as the dependent variable. Inclusion of crop stand as a competitive factor significantly improved the fit of all regression models tested. Wild oat were more competitive against wheat in these experiments than in experiments reported by others. Possible reasons for differences in observed competitiveness are discussed.

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Effects of Spring Wheat Seed Size and Reduced Rates of Tralkoxydim on Wild Oat Control, Wheat Yield, and Economic Returns

Weed Technology ◽

10.1614/wt-05-152r.1 ◽

2006 ◽

Vol 20 (2) ◽

pp. 472-477 ◽

Cited By ~ 2

Author(s):

Qingwu Xue ◽

Robert N. Stougaard

Keyword(s):

Seed Size ◽

Spring Wheat ◽

Weed Management ◽

Wheat Yield ◽

Wild Oat ◽

Wheat Seed ◽

Economic Returns ◽

Size Classes ◽

Large Seed ◽

Combined Use

Spring wheat competitive ability has recently been demonstrated to co-vary with seed size. The objective of this study was to determine if spring wheat seed size would influence the effects of variable tralkoxydim rates on wild oat control, wheat yield, and economic returns. The factorial treatment arrangement consisted of three spring wheat seed size classes and five tralkoxydim rates. Wild oat density, panicles, and biomass decreased as spring wheat seed size and tralkoxydim rate increased, with the combined effect being additive. Wild oat variables decreased in a log-logistic manner as tralkoxydim rate increased during both years. However, tralkoxydim was less effective in 2000 than 2002, as indicated by the higher dosage required to reduce the wild oat variables by 50% (greaterI50values). In contrast, the effect of large seeded wheat in suppressing wild oat was more consistently expressed, with wild oat variables decreasing linearly as seed size increased. Wheat yield and economic returns increased exponentially as tralkoxydim rate increased. At the same time, wheat yield and economic returns were greater for wheat plants derived from large seed compared to those derived from small seed. Averaged over all other factors, adjusted gross returns of 578, 657, and 703 $/ha were realized for the small, medium, and large seed size classes, respectively. The combined use of large seeded wheat plus tralkoxydim applications provided greater wild oat control than did either single tactic. The use of large seeded wheat had a stabilizing effect that increased the consistency and durability of the weed management system while simultaneously improving economic returns.

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Variable crop plant establishment contributes to differences in competitiveness with wild oat among cereal varieties

Canadian Journal of Plant Science ◽

10.4141/p04-190 ◽

2005 ◽

Vol 85 (4) ◽

pp. 771-776 ◽

Cited By ~ 13

Author(s):

John T. O’Donovan ◽

Robert E. Blackshaw ◽

K. Neil Harker ◽

George W. Clayton ◽

Ross McKenzie

Keyword(s):

Spring Wheat ◽

Field Experiments ◽

Plant Density ◽

Crop Plant ◽

Wheat Crop ◽

Wild Oat ◽

Seeding Rate ◽

Hordeum Vulgare L ◽

Wheat Varieties ◽

Crop Density

Field experiments were conducted at three locations in Alberta to determine the relative competitiveness with wild oat (Avena fatua L.) of three hard red spring (HRS) and three Canada prairie spring (CPS) wheat (Triticum aestivum L.) varieties and a semidwarf hull-less barley (Hordeum vulgare L.) (Falcon), and normal height general purpose barley (AC Lacombe). Crop variety significantly affected crop yield loss, wild oat shoot dry weight and wild oat seed yield (competitive indicators). AC Lacombe barley was consistently more competitive than Falcon barley or any of the wheat varieties, while the HRS wheat varieties were mainly more competitive than the CPS varieties. Falcon barley was generally similar in competitiveness to the CPS wheat varieties. Differences among varieties in crop plant density at establishment correlated significantly with the competitive indicators suggesting that this factor contributed to the differences in competitiveness among the varieties. Crop density tended to be higher with the more competitive AC Lacombe barley and HRS wheat varieties than with the less competitive Falcon barley and CPS wheat varieties. Variety and seeding rate did not interact significantly but intentionally increasing the seeding rate improved the competitiveness of all varieties. Key words: Hard red spring wheat, Canada prairie spring wheat, crop seeding rate, hull-less barley, semi-dwarf wheat and barley

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