Interference of turnipweed (Rapistrum rugosum) and Mexican pricklepoppy (Argemone mexicana) in wheat

AbstractTurnipweed [Rapistrum rugosum (L.) All.] and Mexican pricklepoppy (Argemone mexicana L.) are increasingly prevalent in the northern cropping regions of Australia. The effect of different densities of these two weeds was examined for their potential to cause yield loss in wheat (Triticum aestivum L.) through field studies in 2016 and 2017. There was 72% to 78% yield reduction in wheat due to competition from R. rugosum. Based on the exponential decay model, 18.2 and 24.3 plants m−2 caused a yield reduction of 50% in 2016 and 2017, respectively. Rapistrum rugosum produced a maximum of 32,042 and 29,761 seeds m−2 in 2016 and 2017, respectively. There was 100% weed seed retention at crop harvest. Competition from A. mexicana resulted in a yield loss of 17% and 22% in 2016 and 2017, respectively; however, plants failed to set seeds due to intense competition from wheat. Among the yield components, panicles per square meter and grains per panicle were affected by weed competition. The studies indicate a superior competitiveness of R. rugosum in wheat and a suppressive effect of wheat on A. mexicana. The results indicate that a wheat crop can be included in crop rotation programs where crop fields are infested with A. mexicana. High seed retention in R. rugosum indicates the possibility to manage this weed through seed catching and harvest weed seed destruction.

Download Full-text

Interference of Annual Sowthistle (Sonchus oleraceus) in Wheat

Weed Science ◽

10.1017/wsc.2019.69 ◽

2019 ◽

pp. 1-21 ◽

Cited By ~ 2

Author(s):

Sudheesh Manalil ◽

Hafiz Haider Ali ◽

Bhagirath Singh Chauhan

Keyword(s):

Weed Management ◽

Field Studies ◽

Integrated Weed Management ◽

Yield Reduction ◽

Sonchus Oleraceus ◽

Poor Seed ◽

Exponential Decay Model ◽

Weed Infestation ◽

Varying Environments ◽

Asteraceae Family

Abstract Annual sowthistle (Sonchus oleraceus L.) is a broadleaf weed that is increasing in prevalence in the northern cropping regions of Australia. Being a member of Asteraceae family, this weed possesses many biological attributes needed to thrive in varying environments and weed management pressure. Interference of this weed was examined in a wheat (Triticum aestivum L.) crop through field studies in 2016 and 2017. Different densities of S. oleraceus were evaluated for their potential to cause yield loss in wheat: 0.0 (weed free), low (9 to 15 plants m−2), medium (29 to 38 plants m−2), and high (62 to 63 plants m−2). Based on the exponential decay model, 43 and 52 plants m−2 caused a yield reduction of 50% in 2016 and 2017, respectively. Yield components such as panicles m−2 and grains per panicles were affected by weed density. At the high weed infestation level, S. oleraceus produced a maximum of 182,940 and 192,657 seeds m−2 in 2016 and 2017, respectively. Sonchus oleraceus exhibited poor seed retention at harvest as more than 95% of seeds were blown away by wind. Adverse effects on crop, high seed production and wind-blown dispersal may lead to an increased prevalence of this weed in the absence of an integrated weed management strategy utilizing both herbicides and non-chemical options.

Download Full-text

Influence of Crop Competition and Harvest Weed Seed Control on Rigid Ryegrass (Lolium rigidum) Seed Retention Height in Wheat Crop Canopies

Weed Science ◽

10.1017/wsc.2018.28 ◽

2018 ◽

Vol 66 (5) ◽

pp. 627-633 ◽

Cited By ~ 9

Author(s):

Michael J. Walsh ◽

John C. Broster ◽

Charlotte Aves ◽

Stephen B. Powles

Keyword(s):

Wheat Crop ◽

Average Height ◽

Crop Canopy ◽

Lolium Rigidum ◽

Weed Seed ◽

Seed Retention ◽

Rigid Ryegrass ◽

Crop Maturity ◽

Crop Competition

AbstractHarvest weed seed control (HWSC) is an Australian innovation, developed to target high proportions of weed seed retained at crop maturity by many major weed species. There is the potential, however, that a reduction in the average height of retained seed is an adaptation to the long-term use of HWSC practices. With the aim of examining the distribution of rigid ryegrass (Lolium rigidumGaudin) seed through crop canopies, a survey of Australian wheat (Triticum aestivumL.) fields was conducted at crop maturity. Nine sites with medium to long-term HWSC use were specifically included to examine the influence of HWSC use on seed retention height. During the 2013 wheat harvest,L. rigidumand wheat plant samples were collected at five heights downward through the crop canopy (40, 30, 20, 10, and 0 cm above ground level) in 71 wheat fields. Increased crop competition resulted in higher proportions ofL. rigidumseed in the upper crop canopy (>40 cm). The increase in plant height is likely a shade-intolerance response ofL. rigidumplants attempting to capture more light. This plant attribute creates the opportunity to use crop competition to improve HWSC efficacy by increasing the average height of seed retention. Crop competition can, therefore, have a double impact by reducing overallL. rigidumseed production and increasing seed retention height. Examining the distribution of wheat biomass andL. rigidumseed through the crop canopy, we determined that reducing harvest height for HWSC considerably increased the collection ofL. rigidumseed (25%) but to a lesser extent wheat crop biomass (14%). Comparison of + and − HWSC use at nine locations found no evidence of adaptation to this form of weed control following 5 to 10 yr of use. Although the potential for resistance to HWSC remains, these results indicate that this will not readily occur in the field.

Download Full-text

Seed Retention of Grass Weeds at Wheat Harvest in the Pacific Northwest

Weed Science ◽

10.1017/wsc.2020.91 ◽

2020 ◽

pp. 1-32

Author(s):

Carolina San Martín ◽

Mark E Thorne ◽

Jennifer A Gourlie ◽

Drew J Lyon ◽

Judit Barroso

Keyword(s):

Pacific Northwest ◽

Seed Production ◽

Secale Cereale ◽

Bromus Tectorum ◽

Wheat Crop ◽

Weed Seed ◽

Weed Species ◽

Seed Shattering ◽

Seed Retention ◽

The Pacific

Abstract Harvest weed seed control (HWSC) may control problematic weeds by decreasing contributions to the weed seed bank. However, HWSC practices will not be effective if plants have shed a great part of their seeds before harvest, or if a low proportion of seed production is retained at a height that enables collection during harvest. The seed shattering pattern of several weed species was evaluated over three growing seasons to determine their potential to be controlled with HWSC in the Pacific Northwest (PNW). The studied weed species were downy brome (Bromus tectorum L.), feral rye (Secale cereale L.), Italian ryegrass [Lolium perenne ssp. multiflorum (Lam.) Husnot,], and rattail fescue [Vulpia myuros (L.) C.C. Gmel.]. Seed retention at harvest, seed production, and plant height differed among species, locations, and years. Environmental conditions influenced seed shattering patterns, particularly the time plants started to shatter seeds and the rate of the shattering. Agronomic factors such as herbicide use, inter-row space, or crop height/vigor also seemed to affect shattering patterns and seed production, but more specific studies must be conducted to determine their individual effects. Bromus tectorum, L. perenne ssp. multiflorum, and V. myuros had an average seed retention at harvest of less than 50%. In addition, the low seed retention height of V. myuros makes this species a poor candidate for HWSC. Secale cereale had average seed retention at harvest greater than 50% and seed retention height was greater than 30 cm. The variability of seed retention in different species will make the efficacy of HWSC practices species and environment dependent in PNW winter wheat cropping systems. Harvesting the wheat crop as early as possible will be crucial to the success of HWSC.

Download Full-text

Interference of Wild Oats (Avena fatua) and Sterile Oats [Avena sterilis ssp. ludoviciana (Durieu)] in Wheat

Weed Science ◽

10.1017/wsc.2021.25 ◽

2021 ◽

pp. 1-20

Author(s):

Gulshan Mahajan ◽

Bhagirath Singh Chauhan

Keyword(s):

Yield Loss ◽

Winter Season ◽

Avena Fatua ◽

Yield Reduction ◽

Infestation Level ◽

Weed Seed ◽

Avena Sterilis ◽

Good Opportunity ◽

Wide Range ◽

Weed Infestation

Abstract Wild oat (Avena fatua L.) and sterile oat [Avena sterilis ssp. ludoviciana (Durieu) Gillet & Magne; referred to as A. sterilis here], winter season weeds, are increasing their prevalence in the eastern grain region of Australia. Biological attributes of these weeds enable them to survive in a wide range of environments and under different weed infestation levels. The interference of A. fatua and A. sterilis in a wheat (Triticum aestivum L.) crop was examined in southeast Queensland, Australia through field studies in 2019 and 2020. Different infestation levels (0, 3, 6, 12, 24, and 48 plants m−2) of A. fatua and A. sterilis were evaluated for their potential to cause yield losses in wheat. Based on a three-parameter logarithmic model, the A. fatua and A. sterilis infestation levels corresponding to 50% wheat yield loss were 15 and 16 plants m−2, respectively. The yield reduction was due to a reduced spike number per unit area because of an increased weed infestation level. At the highest weed infestation level (48 plants m−2), A. fatua and A. sterilis produced a maximum of 4,800 and 3,970 seeds m−2, respectively. A. fatua exhibited lower seed retention (17-39%) than A. sterilis (64-80%) at wheat harvest, as most of the seeds of A. fatua had shattered at crop maturity. Our results implied that there is a good opportunity for harvest weed seed control if the paddock is infested with A. sterilis. This study suggests that in the absence of an integrated weed management strategy (using both chemical and nonchemical options), a high infestation of these weeds could cause a severe crop yield loss, increase weed seed production, and replenish weed seedbank in the soil.

Download Full-text

Winter Wheat Response to Preplant Applications of Aminocyclopyrachlor

Weed Technology ◽

10.1614/wt-d-10-00049.1 ◽

2011 ◽

Vol 25 (1) ◽

pp. 51-57 ◽

Cited By ~ 20

Author(s):

Andrew R. Kniss ◽

Drew J. Lyon

Keyword(s):

Winter Wheat ◽

Yield Loss ◽

Wheat Yield ◽

Field Studies ◽

Wheat Crop ◽

Yield Losses ◽

Fallow Period ◽

Winter Wheat Yield ◽

Winter Wheat Crop ◽

Preceding Winter

Field studies were conducted in Wyoming and Nebraska in 2007 through 2009 to evaluate winter wheat response to aminocyclopyrachlor. Aminocyclopyrachlor was applied at rates between 15 and 120 g ai ha−1 6, 4, and 2 mo before winter wheat planting (MBP). Redroot pigweed control was 90% with aminocyclopyrachlor rates of 111 and 50 g ha−1 when applied 4 or 2 MBP. Aminocyclopyrachlor at 37 g ha−1 controlled Russian thistle 90% when applied 6 MBP. At Sidney, NE, winter wheat yield loss was > 10% at all aminocyclopyrachlor rates when applied 2 or 4 MBP, and at all rates > 15 g ha−1 when applied 6 MBP. At Lingle, WY, > 40% winter wheat yield loss was observed at all rates when averaged over application timings. Although the maturing wheat plants looked normal, few seed were produced in the aminocyclopyrachlor treatments, and therefore preharvest wheat injury ratings of only 5% corresponded to yield losses ranging from 23 to 90%, depending on location. The high potential for winter wheat crop injury will almost certainly preclude the use of aminocyclopyrachlor in the fallow period immediately preceding winter wheat.

Download Full-text

Understanding the Competitive Effects of Blessed Milkthistle Densities on Wheat

Planta Daninha ◽

10.1590/s0100-83582020380100010 ◽

2020 ◽

Vol 38 ◽

Author(s):

A. REHMAN ◽

R. QAMAR ◽

M.E. SAFDAR ◽

H.M.R. JAVEED ◽

M. SHEHZAD ◽

...

Keyword(s):

Weed Management ◽

Yield Loss ◽

Cost Effective ◽

Field Studies ◽

Wheat Crop ◽

Yield Losses ◽

Comprehensive Understanding ◽

Gradual Reduction ◽

Competitive Effects ◽

1000 Grain Weight

ABSTRACT: Weed-induced yield loss in wheat crop is a great threat to food security in Pakistan. A comprehensive understanding of weed-crop competition is very important to develop sustainable and cost-effective weed management. For this purpose, two-year field studies were conducted to determine the effect of different blessed milkthistle densities on the phenology and yield of wheat crop in a rice-wheat cropping scheme in Sargodha, Pakistan during 2013-2014 and 2014-2015. The experiment comprised seven treatments: control (weed free), weedy check (weedy without any control) and blessed milkthistle densities of 5, 10, 15, 20 and 25 plants m-2. In response to increasing weed density, a gradual reduction in yield and yield-related traits of wheat was noted. Compared to the weed-free control, a significant reduction in number of productive tillers m-2 (20% and 18%), plant height (15% and 18%), spike length (19% and 26%), number of grains spike-1 (23% and 26%), 1000 grain weight (28% and 28%), grain (29% and 30%) and biological (20% and 24%) yields of wheat occurred at and beyond blessed milkthistle density of 5 plants m-2 during 2013-2014 and 2014-2015 respectively. It can be concluded that blessed milkthistle weed must be controlled if its population density reaches 5 plants m-2 in order to avoid significant grain yield losses in wheat.

Download Full-text

Yield Reductions of Wheat Cultivar Obora (UTIQUE96/FLAG-1) due to Russian Wheat Aphid (Diuraphis noxia) Infestation under Field Conditions at Selected Districts of West Showa Zone, Ethiopia

Agricultural Science Digest - A Research Journal ◽

10.18805/ag.d-366 ◽

2022 ◽

Author(s):

Nahil Abebe ◽

Mulugeta Negeri ◽

Emana Getu ◽

Thangavel Selvara

Keyword(s):

Yield Loss ◽

Insect Pests ◽

Triticum Aestivum L ◽

Russian Wheat Aphid ◽

Diuraphis Noxia ◽

Wheat Crop ◽

Yield Reduction ◽

Cereal Crop ◽

Cropping Season ◽

Maximum Decrease

Background: Wheat (Triticum aestivum L.) is an important cereal crop as being consumed as staple food in the world as well as in Ethiopia. The production of wheat in Ethiopia decreased due to the incidence of insect pests. Out of insects’ pests the Russian wheat aphid (Diuraphis noxia) is the recent one that causes yield loss either directly or indirectly. Methods: The experiment was carried out at selected districts of West Showa zone, Ethiopia during off cropping season 2019 to evaluate the yield reduction in wheat crop due to the invasion of Russian wheat aphids. Malamar, Dimethoate, neem seeds, leaves, Beaveria bassiana and Metarhizium anisopliae were used in form of spray. Result: However, Malamar and Dimethoate highly significantly lowered the population of Diuraphis noxia. The combination of Beaveria bassiana and Metarhizium anisopleae significantly lowered the population of Russian wheat aphid. The combination of Neem leaf and Neem seeds, as well as Beaveria bassiana, proved to be effective against Russian wheat aphid yet they were protected and sound against the environments. Malamar showed the maximum decrease in Diuraphis noxia populations followed by Dimethoate, the combination of Beaveria bassiana and Metarhizium anisopleae.

Download Full-text

Modelling the Economics of Controlling Nodding Broomrape (Orobanche cernua) in Sunflower (Helianthus annuus)

Weed Science ◽

10.1017/s004317450009439x ◽

1996 ◽

Vol 44 (3) ◽

pp. 591-595 ◽

Cited By ~ 6

Author(s):

L. García-Torres ◽

M. Castejón-Muñoz ◽

M. Jurado-Expósito ◽

F. López-Granados

Keyword(s):

Helianthus Annuus ◽

Crop Yield ◽

Treatment Cost ◽

Yield Loss ◽

Field Studies ◽

Control Treatment ◽

Yield Reduction ◽

Economic Threshold ◽

Economic Thresholds ◽

Crop Yield Loss

Field studies were conducted at nine locations in southern Spain during 2 yr to develop models of nodding broomrape competition with sunflower and to establish economic thresholds. At each location, 30 to 35 small plots, each consisting of three sunflower plants, were chosen at random. The infection severity (BIS, no. of emerged broomrapes per sunflower plant) varied from 0 to 35. Plots were harvested at maturity to assess several sunflower and broomrape population variables. The percent sunflower yield reduction averaged over locations due to broomrape was estimated by the equation: % SYR = 1.7 x BIS (r2= 0.92). Crop yield loss per BIS unit increased with the expected yield and was estimated to be about 25, 50, and 75 kg ha−1for yields of 1000, 2000, and 3000 kg ha−1, respectively. A consistent relationship could be established between broomrape-infected sunflower yield, crop and broomrape biomass, and BIS parameters: SSYI= 0.2259 x PoBio/(1 + 0.0687 x BIS) (r2= 0.7820). The BIS economic threshold was about 1.5 and 3.5 for control treatment cost of $ 40 ha−1and potential yields of 2000 and 1000 kg ha−1, respectively.

Download Full-text

Enhanced wheat competition effects on the growth, seed production, and seed retention of major weeds of Australian cropping systems

Weed Science ◽

10.1017/wsc.2019.53 ◽

2019 ◽

Vol 67 (6) ◽

pp. 657-665 ◽

Cited By ~ 2

Author(s):

Michael J. Walsh

Keyword(s):

Seed Production ◽

Wheat Crop ◽

Crop Canopy ◽

Raphanus Raphanistrum ◽

Weed Seed ◽

Weed Biomass ◽

Bromus Diandrus ◽

Seed Retention ◽

Competition Effects ◽

Crop Competition

AbstractThe loss of herbicide options due to resistance and lack of new chemistries have delivered the realization that herbicides are a finite resource and weed control alternatives are desperately needed. In Australian conservation cropping, the only available alternatives suited to routine use are the recently introduced harvest weed seed control (HWSC) and the ever-present but undervalued crop competition. Target-neighbor design pot studies examined wheat (Triticum aestivum L.) competition effects on biomass and seed production of rigid ryegrass (Lolium rigidum Gaudin), wild radish (Raphanus raphanistrum L.), ripgut brome (Bromus diandrus Roth), and wild oat (Avena fatua L.). The influence of wheat competition on crop canopy distribution of weed biomass and seed production was also examined. At the current commercially targeted wheat density (120 plants m−2) weed biomass was reduced by 69%, 73%, 72%, and 49% and seed production by 78%, 78%, 77%, and 50% for L. rigidum, R. raphanistrum, B. diandrus, and A. fatua, respectively, when compared with no competition. These results highlighted the importance of uniform wheat crop establishment in minimizing the ongoing impact of weeds. Enhanced what competition (from 120 to 400 plants m−2) resulted in further smaller, but substantial, reductions in biomass (19%, 13%, 20%, and 39%) and seed production (12%, 13%, 17%, and 45%) for L. rigidum, R. raphanistrum, B. diandrus, and A. fatua, respectively. This enhanced competition also increased weed seed retention in the upper crop canopy (>40 cm) by 35% and 31% for L. rigidum and B. diandrus, respectively, but not for A. fatua and R. raphanistrum, for which weed seed retention was already >80% at the wheat density of 120 plants m−2. Enhanced wheat crop competition, then, has the dual effect of restricting the growth and development of L. rigidum, R. raphanistrum, B. diandrus, and A. fatua as well increasing the susceptibility of these weed species to HWSC.

Download Full-text

Sulfentrazone Persistence in Southern Soils: Bioavailable Concentration and Effect on a Rotational Cotton Crop

Weed Technology ◽

10.1614/wt-03-091r1 ◽

2004 ◽

Vol 18 (2) ◽

pp. 346-352 ◽

Cited By ~ 12

Author(s):

Christopher L. Main ◽

Thomas C. Mueller ◽

Robert M. Hayes ◽

John W. Wilcut ◽

Thomas F. Peeper ◽

...

Keyword(s):

North Carolina ◽

Yield Loss ◽

Field Studies ◽

Lint Yield ◽

Yield Reduction ◽

Cotton Lint ◽

Cotton Crop ◽

Cotton Lint Yield ◽

Rotational Crop

Field studies were conducted from 1998 to 2000 in Tennessee, North Carolina, Arkansas, and Oklahoma to determine the effects of sulfentrazone carryover to a cotton rotational crop from sulfentrazone applied the previous year. Sulfentrazone applied the previous year at 400 g/ha caused no yield loss in Tennessee, >30% yield reduction in Oklahoma, and 20% yield loss in Arkansas and North Carolina. In most experiments in this study, visual evaluations of injury closely correlated with final cotton lint yield (r2=0.84).

Download Full-text