Fertilizer placement affects growth and reproduction of three common weed species in pine bark–based soilless nursery substrates

AbstractWeed management in container crops is primarily accomplished through frequent PRE herbicide applications and supplemental hand weeding. However, many ornamental species are sensitive to herbicides, and a significant number of tropical plants, ornamental grasses, and foliage crops have not been screened for herbicide tolerance. As nursery crops are produced in inert substrates that are largely composed of bark or peat, strategic fertilizer placement has the potential to significantly reduce weed growth in container-grown ornamentals. Growth and reproduction of three common container nursery weed species, eclipta [Eclipta prostrata (L.) L.], large crabgrass [Digitaria sanguinalis (L.) Scop.], and spotted spurge (Euphorbia maculata L.), were evaluated following fertilization via alternative methods, including subdressing or dibbling in comparison with industry standard practices of topdressing or incorporating a controlled-release fertilizer (17-5-11 [8 to 9 mo.]) to each 3.8-L container at 36.5 g per container. Fertilizer placement had little to no effect on germination of Eclipta prostrata or D. sanguinalis, but incorporation increased E. maculata germination by 77% to 183% compared with other placements or a nonfertilized control. Subdressing reduced seed production by 94%, 63%, and 92% for Eclipta prostrata, D. sanguinalis, and E. maculata, respectively, compared with the average number of seeds produced in the conventional placement methods (average of incorporation and topdressing). Dibbling fertilizer resulted in similar decreases in the case of D. sanguinalis and E. maculata, while Eclipta prostrata produced no seeds when fertilizer was dibbled. Similar to reductions observed in reproduction, subdressing fertilizer resulted in biomass decreases of 90%, 81%, and 85% compared with the average biomass of the incorporation and topdressed placements. Results suggest alternative fertilizer placements could be implemented as part of an integrated weed management program in container production to reduce weed growth.

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Effects of Three Fertilization Methods on Weed Growth and Herbicide Performance in Soilless Nursery Substrates1

Journal of Environmental Horticulture ◽

10.24266/0738-2898-36.4.133 ◽

2018 ◽

Vol 36 (4) ◽

pp. 133-139

Author(s):

Cody J. Stewart ◽

S. Christopher Marble ◽

Brian E. Jackson ◽

Brian J. Pearson ◽

P. Christopher Wilson

Keyword(s):

Fertilizer Treatment ◽

Fertility Rates ◽

Weed Species ◽

Fertilizer Placement ◽

Digitaria Sanguinalis ◽

Fertilizer Rate ◽

Weed Growth ◽

Eclipta Prostrata ◽

Preemergence Herbicides ◽

Large Crabgrass

Abstract Research objectives were to determine the effect of fertilization method (incorporation, subdress, and topdress) on weed growth and the performance of preemergence herbicides applied to soilless substrates. Nursery containers were filled with a pine bark:peat substrate and fertilized at two different rates [4.4 and 9.5 kg.m−3 (8.9 and 19.2 lb.yd−3)] via topdressing, subdressing, or incorporating. Containers were treated with either dimethenamid-P for spotted spurge (Euphorbia maculata L.), flumioxazin for eclipta (Eclipta prostrata L.) or prodiamine for large crabgrass (Digitaria sanguinalis L.). A control was established for each fertilizer rate/placement and weed species that was not treated. Incorporating or subdressing fertilizer resulted in reduced large crabgrass and spotted spurge growth in non-treated containers. Weeds grew larger at the higher fertility rates in both topdress and incorporated treatments but fertilizer rate did not affect growth of spotted spurge or large crabgrass when fertilizers were subdressed. Herbicides generally provided commercially acceptable weed control regardless of fertilizer treatment, but results varied with species. Results suggest that in the absence of herbicides, topdressing may result in greater weed growth compared with subdressing or incorporating fertilizers; however, fertilizer placement will have less impact on herbicide performance if proper herbicides are chosen and applied correctly. Index words: topdress, subdress, incorporate, large crabgrass, eclipta, spotted spurge, preemergence Chemicals used in this study: Flumioxazin (SureGuard®); 2-[7-fluoro-3,4-dihydro-3-oxo-4-(2-propynyl)-2H-1,4-benzoxazin-6-yl]-4,5,6,7-tetrahydro-1H-isoindole1,3(2H)-dione; Dimethenamid-P (Tower) 2-chloro-N-[(2,4-dimethyl-3-thienyl)-N-(2-methoxy-1-methylethyl)acetamide; Prodiamine (Barricade) 2,4-dinitro-N3, N3-dipropyl-6-(trifluoromethyl)-1,3-benzenediamine (Barricade®) Species used in this study: Large crabgrass (Digitaria sanguinalis L.); Eclipta (Eclipta prostrata L.); Spotted spurge (Euphorbia maculata L.)

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Phosphorus Fertilizer Application Method Affects Weed Growth and Competition with Wheat

Weed Science ◽

10.1614/ws-08-173.1 ◽

2009 ◽

Vol 57 (3) ◽

pp. 311-318 ◽

Cited By ~ 18

Author(s):

Robert E. Blackshaw ◽

Louis J. Molnar

Keyword(s):

Weed Management ◽

Wheat Yield ◽

Fertilizer Application ◽

Management Systems ◽

Integrated Weed Management ◽

Weed Species ◽

Application Method ◽

Weed Growth ◽

P Fertilizer ◽

Application Methods

Strategic fertilizer management is an important component of integrated weed management systems. A field study was conducted to determine the effect of various application methods of phosphorus (P) fertilizer on weed growth and wheat yield. Weed species were chosen to represent species that varied in their growth responsiveness to P: redroot pigweed (medium), wild mustard (medium), wild oat (medium), green foxtail (high), redstem filaree (high), and round-leaved mallow (high). P fertilizer application methods were seed placed at a 5-cm depth, midrow banded at a 10-cm depth, surface broadcast immediately before seeding, and surface broadcast immediately after seeding of wheat. An unfertilized control was included. P treatments were applied to the same plot in four consecutive years to determine annual and cumulative effects over years. Shoot P concentration and biomass of weeds were often lower with seed-placed or subsurface-banded P fertilizer compared with either surface-broadcast application method. This result occurred more frequently with the highly P-responsive weeds and was more evident in the latter study years. P application method had little effect on weed-free wheat yield but often had a large effect on weed-infested wheat yield. Seed-placed or midrow-banded P compared with surface-broadcast P fertilizer often resulted in higher yields when wheat was in the presence of competitive weeds. Seedbank determinations at the conclusion of the study indicated that the seed density of five of six weed species was reduced with seed-placed or subsurface-banded P compared with surface-broadcast P. Information gained in this study will aid development of more effective weed management systems in wheat.

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Influence of Cereal Rye Management on Weed Control in Soybean

Frontiers in Agronomy ◽

10.3389/fagro.2020.600568 ◽

2020 ◽

Vol 2 ◽

Author(s):

Kurt M. Vollmer ◽

Mark J. VanGessel ◽

Quintin R. Johnson ◽

Barbara A. Scott

Keyword(s):

Weed Control ◽

Weed Management ◽

Cover Crop ◽

Management Program ◽

Weed Suppression ◽

Integrated Weed Management ◽

Weed Species ◽

Delayed Effect ◽

Cereal Rye ◽

Winter Annual

Cereal rye as a cover crop is often used to improve soil health and as part of integrated weed management programs. Despite this, cereal rye biomass is often not managed for optimal weed suppression. This study evaluated the effects of managing cereal rye as part of an integrated weed management strategy in soybean. Factors consisted of levels of cereal rye management (no cereal rye, no nitrogen, or 20 kg/ha of nitrogen); cereal rye termination timing (20 or 10 d before soybean planting); and residual herbicide treatment applied at cereal rye termination (with or without). Winter annual weed control with cereal rye was generally greater compared to no cereal rye. Winter annual weed control was consistently better when cereal rye was terminated at 20 d before soybean planting compared to 10 d; while summer annual weed control was improved if termination was delayed. Effect of cereal rye management on summer annual weed control varied by weed species. In the absence of residual herbicides, Palmer amaranth control responded to the different levels of cereal rye management. However, morningglory spp. only responded to rye with supplemental N applications. Large crabgrass control was similar for treatments containing cereal rye, regardless of nitrogen input. Our results demonstrate the importance of cover crop management when incorporating cereal rye into an integrated weed management program for soybean.

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Assessment of weed and crop fitness in cover crop residues for integrated weed management

Weed Science ◽

10.1017/s0043174500091153 ◽

1998 ◽

Vol 46 (5) ◽

pp. 595-603 ◽

Cited By ~ 52

Author(s):

Martin M. Williams ◽

David A. Mortensen ◽

John W. Doran

Keyword(s):

Weed Control ◽

Weed Management ◽

Cover Crop ◽

Field Experiments ◽

Crop Residues ◽

Seedling Emergence ◽

Integrated Weed Management ◽

Weed Species ◽

Weed Growth ◽

Canopy Volume

Cover crop residues are not widely used for weed control because, as a stand-alone tactic, they do not effectively suppress all weeds and their duration of weed control is too short. Field experiments were conducted in 1995 and 1996, under both irrigated and rainfed conditions, to quantifyAmaranthusspp.,Setariaspp., and soybean emergence and growth in residues of fall-planted, spring-killed barley, rye, triticale, wheat, and hairy vetch. For both weed species, seedling emergence was reduced 3 wk after soybean planting by rye and wheat residues (≥ 2, 170 kg ha−1) in 1996. In 1996,Amaranthusspp. canopy volume was reduced 38 to 71% by residues 3 wk after planting. Likewise,Setariaspp. canopy biomass was reduced 37 to 97% in residues 5 wk after planting over both years. The response comparison index was used to identify frequency by which weed growth was placed at a disadvantage relative to soybean growth.Amaranthusspp. andSetariaspp. growth suppressions 3 to 5 wk after planting indicate potential times for intervention with other integrated weed management tactics such as reduced postemergence herbicide rates and interrow cultivation.

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Herbicide resistant weeds: the case of resistance to glyphosate

Vietnam Journal of Science Technology and Engineering ◽

10.31276/vjste.63(2).74-80 ◽

2021 ◽

Vol 63 (2) ◽

pp. 74-80

Author(s):

The Duc Ngo ◽

Keyword(s):

Weed Management ◽

Glyphosate Resistance ◽

Resistance Mechanisms ◽

Management Program ◽

Ambrosia Artemisiifolia ◽

Target Site ◽

Integrated Weed Management ◽

Weed Species ◽

Site Mutation ◽

Sites Of Action

Glyphosate has become the most widely used herbicide worldwide since 1974 with a global use of 8.6 billion kg (glyphosate active ingredient) between 1974 and 2014. This study reports on glyphosate resistant (GR) weeds and their resistance mechanisms based on global scientifically reported cases. Forty-nine different weed species have evolved resistance to glyphosate in 29 countries with a total of 318 identified cases worldwide. Fifty percent of these resistance cases were found in glyphosate-resistant cropping systems. There were 255 identified cases (80.2%) of glyphosate resistance in the top five countries (in terms of number of cases and species), namely USA, Australia, Argentina, Brazil, and Canada. The five most popular weed species (in terms of number of cases) found to be resistant to glyphosate were Conyza canadensis, Amaranthus palmeri, Amaranthus tuberculatus, Lolium perenne ssp. Multiflorum,and Ambrosia artemisiifolia with 42, 42, 29, 26, and 21 reported cases, respectively. Out of 49 weed species, 19 GR weed species were found to not only be resistant to glyphosate but also to other herbicide sites of action (multiple herbicide resistance). Glyphosate resistance mechanisms in weeds include (1) target-site alterations: target-site mutation and target-site gene amplification; and (2) non-target-site mechanisms involving different modes of exclusion from the target site: reduced glyphosate uptake, reduced glyphosate translocation, and enhanced glyphosate metabolism. It is essential to have an integrated weed management program that includes not only smart herbicide mixtures and rotations, but also cultural, manual, mechanical, and crop-based weed management methods.

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Glyphosate as a Tool for the Incorporation of New Herbicide Options in Integrated Weed Management in Maize: A Weed Dynamics Evaluation

Agronomy ◽

10.3390/agronomy9120876 ◽

2019 ◽

Vol 9 (12) ◽

pp. 876

Author(s):

Iñigo Loureiro ◽

Inés Santin-Montanyá ◽

María-Concepción Escorial ◽

Esteban García-Ruiz ◽

Guillermo Cobos ◽

...

Keyword(s):

Species Diversity ◽

Weed Management ◽

Management Program ◽

Integrated Weed Management ◽

Weed Species ◽

Additional Tool ◽

Cropping Season ◽

Farm Scale ◽

Weed Dynamics ◽

The Impact

A farm-scale investigation was conducted to evaluate the potential impact of integrating glyphosate into different weed management programs when cultivating herbicide-tolerant maize in central Spain from 2012 to 2014. The weed management programs were (1) a conventional weed management with pre- and post-emergent herbicide applications, (2) a weed management program in which the number and total amount of conventional herbicides applied were reduced, and (3) three weed management programs that comprised either two post-emergent applications of the herbicide glyphosate, or only one glyphosate application combined with pre- and/or post-emergent herbicides. Weed density throughout each cropping season was greater in those weed management programs that did not include a pre-emergence application of herbicides than those that did. Moreover, none of the weed management programs affected the richness and species diversity of the weeds or reduced yields. Although the impact of the different programs was similar in terms of weed species diversity, the composition of the weed community differed and this effect must be considered when providing agroecosystem services. Our results indicate that glyphosate-tolerant maize provides an additional tool that allows integrated weed control of the weed populations without reducing yields.

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Weed Problems in Uruguayan Agriculture: Evolution and Current Situation

Outlooks on Pest Management ◽

10.1564/v32_oct_05 ◽

2021 ◽

Vol 32 (5) ◽

pp. 203-207

Author(s):

M. Alejandro Garcia ◽

Lucia V. Meneses ◽

Tiago Edu Kaspary

Keyword(s):

Weed Management ◽

Agricultural Production ◽

Production Systems ◽

Integrated Weed Management ◽

Zero Tillage ◽

Weed Species ◽

Management Tools ◽

Herbicide Resistant ◽

Species Frequencies ◽

Agricultural Production Systems

Uruguayan agriculture has undergone dramatic changes in the last 50 years driven by the adoption of new agricultural production systems that incorporate zero tillage and herbicide resistant crops. This has resulted in a shift in weed species frequencies and the dispersion of introduced herbicide resistant weed populations. Finally, integrated weed management tools are being developed by research and extension services to manage herbicide-resistant (HR) weeds better and to reduce environmental impact of herbicides.

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Key Aspects on the Biology, Ecology and Impacts of Johnsongrass [Sorghum halepense (L.) Pers] and the Role of Glyphosate and Non-Chemical Alternative Practices for the Management of This Weed in Europe

Agronomy ◽

10.3390/agronomy9110717 ◽

2019 ◽

Vol 9 (11) ◽

pp. 717 ◽

Cited By ~ 1

Author(s):

Travlos ◽

Montull ◽

Kukorelli ◽

Malidza ◽

Dogan ◽

...

Keyword(s):

Weed Management ◽

Control Plant ◽

Field Trials ◽

European Countries ◽

Alternative Methods ◽

Sorghum Halepense ◽

Current Status ◽

Integrated Weed Management ◽

Alternative Practices

Sorghum halepense (L.) Pers is a common and noxious worldwide weed of increasing distribution in many European countries. In the present review, information on the biology, ecology, agricultural, economic and environmental impact of johnsongrass is given, and the current status of this weed in Europe is discussed. Furthermore, special attention is given to the important role of field trials using glyphosate to control weeds in arable and perennial crops in many European countries. Some of the factors which affect control efficacy and should be taken into account are also discussed. Finally, several non-chemical alternative methods (cultural, mechanical, thermal, biological, etc.) for johnsongrass management are also presented. The adoption of integrated weed management (IWM) techniques such as glyphosate use, crop rotation, and deep tillage is strongly recommended to control plant species that originate from both seed and rhizomes.

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Halauxifen-methyl controls glyphosate-resistant horseweed (Conyza canadensis) but not giant ragweed (Ambrosia trifida) in winter wheat

Weed Technology ◽

10.1017/wet.2020.21 ◽

2020 ◽

Vol 34 (4) ◽

pp. 607-612 ◽

Cited By ~ 1

Author(s):

Jessica Quinn ◽

Nader Soltani ◽

Jamshid Ashigh ◽

David C. Hooker ◽

Darren E. Robinson ◽

...

Keyword(s):

Winter Wheat ◽

Weed Management ◽

Field Experiments ◽

The United States ◽

Integrated Weed Management ◽

Conyza Canadensis ◽

Limited Information ◽

Weed Species ◽

Ambrosia Trifida ◽

Giant Ragweed

AbstractHorseweed is a competitive summer or winter annual weed that produces up to 230,000 small seeds per plant that are capable of traveling more than 500 km via wind. Giant ragweed is a tall, highly competitive summer annual weed. Glyphosate-resistant (GR) horseweed and GR giant ragweed pose significant challenges for producers in the United States and Ontario, Canada. It is thought that an integrated weed management (IWM) system involving herbicide rotation is required to control GR biotypes. Halauxifen-methyl is a new selective broadleaf POST herbicide registered for use in cereal crops; there is limited information on its efficacy on horseweed and giant ragweed. The purpose of this research was to determine the efficacy of halauxifen-methyl applied POST, alone and in a tank mix, for the control of GR horseweed and GR giant ragweed in wheat across southwestern Ontario. For each weed species, an efficacy study consisting of six field experiments was conducted over a 2-yr period (2018, 2019). At 8 wk after application (WAA), halauxifen-methyl, fluroxypyr/halauxifen-methyl, fluroxypyr/halauxifen-methyl + MCPA EHE, fluroxypyr + MCPA ester, 2,4-D ester, clopyralid, and pyrasulfotole/bromoxynil + ammonium sulfate controlled GR horseweed >95%. Fluroxypyr and MCPA provided only 86% and 37% control of GR horseweed, respectively. At 8 WAA, fluroxypyr, fluroxypyr/halauxifen-methyl, fluroxypyr/halauxifen-methyl + MCPA EHE, fluroxypyr + MCPA ester, fluroxypyr/halauxifen-methyl + MCPA EHE + pyroxsulam, 2,4-D ester, clopyralid, and thifensulfuron/tribenuron + fluroxypyr + MCPA ester controlled GR giant ragweed 87%, 88%, 90%, 94%, 96%, 96%, 98%, and 93%, respectively. Halauxifen-methyl and pyroxsulam provided only 45% and 28% control of GR giant ragweed, respectively. Halauxifen-methyl applied alone POST in the spring controlled GR horseweed but not GR giant ragweed in winter wheat.

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A New Approach to Weed Management to Mitigate Herbicide Resistance in Argentina

Weed Science ◽

10.1614/ws-d-16-00016.1 ◽

2016 ◽

Vol 64 (SP1) ◽

pp. 641-648 ◽

Cited By ~ 6

Author(s):

Claudio Rubione ◽

Sarah M. Ward

Keyword(s):

Herbicide Resistance ◽

Weed Management ◽

Integrated Weed Management ◽

National Committee ◽

Weed Species ◽

Corn Production ◽

Public And Private ◽

Herbicide Resistant ◽

Crop Varieties ◽

Export Taxes

The evolution of herbicide-resistant weeds is a major concern in the corn- and soybean-producing Pampas region of Argentina, where growers predominantly plant glyphosate-resistant crop varieties and depend heavily on glyphosate for weed control. Currently, 16 weed species in Argentina are resistant to one or more of three different herbicide mechanisms of action, and resistant weed populations continue to increase, posing a serious threat to agricultural production. Implementation of integrated weed management to address herbicide resistance faces significant barriers in Argentina, especially current land ownership and rental patterns in the Pampas. More than 60% of Pampas cropland is rented to tenants for periods that rarely exceed 1 yr, resulting in crop rotation being largely abandoned, and crop export taxes and quotas have further discouraged wheat and corn production in favor of continuous soybean production. In this paper we discuss ways to facilitate new approaches to weed management in Argentina, including legal and economic reforms and the formation of a national committee of stakeholders from public and private agricultural sectors.

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