Comparing Sensor-Based Adjustment of Weed Harrowing Intensity with Conventional Harrowing under Heterogeneous Field Conditions

Setting the right intensity is crucial for the success of post-emergence weed harrowing in cereals. The percentage of crop soil cover (CSC) correlates with the selectivity of weed harrowing. Therefore, real-time camera-based measurements of CSC offer a novel approach to automatically adjust the intensity of harrowing. The intensity of harrowing is varied by hydraulic steering of the tine angle. Five field experiments in cereals were conducted at three locations in southwestern Germany in 2019 and 2020 to measure the effect of camera-based harrowing (2020) and conventional harrowing on weed control efficacy (WCE), crop density, and grain yield. For this purpose, pair-wise comparisons of three fixed harrowing intensities (10°, 40°, and 70° tine angle) and three predefined CSC thresholds (CSC of 10%, 20%, and 60%) were realized in randomized complete block designs. Camera-based intensity adjustment resulted in more homogeneous CSC across the whole plot (6–16% less standard deviation variation) compared to conventional fixed settings of the tine angle. Crop density, WCE, crop biomass, and grain yield were significantly higher for camera-based harrowing than for conventional harrowing. WCE and yields of all automatic adjusted harrowing treatments were equal to the herbicide control plots. Camera-based harrowing provides a robust technology for effective weed management with a lower risk of crop damage than conventional harrowing.

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Rattail fescue (Vulpia myuros) interference and seed production as affected by sowing time and crop density in winter wheat

Weed Science ◽

10.1017/wsc.2020.84 ◽

2020 ◽

pp. 1-10

Author(s):

Muhammad Javaid Akhter ◽

Per Kudsk ◽

Solvejg Kopp Mathiassen ◽

Bo Melander

Keyword(s):

Winter Wheat ◽

Grain Yield ◽

Seed Production ◽

Yield Components ◽

Field Experiments ◽

Growing Season ◽

Sowing Time ◽

Growing Seasons ◽

Crop Density ◽

Wide Range

Abstract Field experiments were conducted in the growing seasons of 2017 to 2018 and 2018 to 2019 to evaluate the competitive effects of rattail fescue [Vulpia myuros (L.) C.C. Gmel.] in winter wheat (Triticum aestivum L.) and to assess whether delayed crop sowing and increased crop density influence the emergence, competitiveness, and fecundity of V. myuros. Cumulative emergence showed the potential of V. myuros to emerge rapidly and under a wide range of climatic conditions with no effect of crop density and variable effects of sowing time between the two experiments. Grain yield and yield components were negatively affected by increasing V. myuros density. The relationship between grain yield and V. myuros density was not influenced by sowing time or by crop density, but crop–weed competition was strongly influenced by growing conditions. Due to very different weather conditions, grain yield reductions were lower in the growing season of 2017 to 2018 than in 2018 to 2019, with maximum grain yield losses of 22% and 50% in the two growing seasons, respectively. The yield components, number of crop ears per square meter, and 1,000-kernel weight were affected almost equally, reflecting that V. myuros’s competition with winter wheat occurred both early and late in the growing season. Seed production of V. myuros was suppressed by delaying sowing and increasing crop density. The impacts of delayed sowing and increasing crop density on seed production of V. myuros highlight the potential of these cultural weed control tactics in the long-term management programs of this species.

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Effects of different cropping systems and weed management methods on free energy and content of pigments in maize

Pesticidi i fitomedicina ◽

10.2298/pif1401045s ◽

2014 ◽

Vol 29 (1) ◽

pp. 45-54 ◽

Cited By ~ 2

Author(s):

Igor Spasojevic ◽

Vesna Dragicevic ◽

Milena Simic ◽

Dusan Kovacevic ◽

Milan Brankov

Keyword(s):

Free Energy ◽

Grain Yield ◽

Weed Management ◽

Positive Impact ◽

Growth Parameters ◽

Cropping Systems ◽

Cropping System ◽

Area Index ◽

Weed Biomass ◽

Crop Density

Rotation is a cropping system that has many advantages and ensures better crop growth and yielding. Its combinination with other cropping measures can ensure optimal crop density for maximal growth and photosynthesis efficiency. The aim of this study was to investigate the influence of different cropping systems: monoculture and two rotations, including maize, wheat and soybean (MSW and MWS), and different weed management methods (weed removal by hoeing, application of a full recommended herbicide dose (RD) and half that dose (0.5 RD), and weedy check) on weed biomass and maize growth parameters - leaf area index (LAI), free energy, contents of chlorophyll and carotenoids, grain yield, and their possible relationships in two fields of the maize hybrids ZP 677 (H1) and ZP 606 (H2). The lowest LAI and grain yield were found in monoculture, particularly in weedy check, which had relatively high weed infestation. Higher weed biomass was also observed in herbicide treated plots in monoculture. Such high competition pressure indicates a stress reflected on reduced LAI and chlorophyll content, and increased free energy and content of carotenoids. On the other hand, rotation, particularly if it is combined with the application of herbicides or hoeing, had a positive impact on yielding potential by increasing LAI and the contents of chlorophyll and carotenoids, and decreasing free energy.

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Variability and interconnection of economically useful indicators of soybeans under the influence of herbicides

The Agrarian Scientific Journal ◽

10.28983/asj.y2020i5pp19-22 ◽

2020 ◽

pp. 19-22

Author(s):

Yuriy Viktorovich Lobachev ◽

Valeriy Tikonovich Krasilnikov

Keyword(s):

Correlation Analysis ◽

Grain Yield ◽

Protein Content ◽

Field Experiments ◽

Specific Effect ◽

Correlation Dependence ◽

Saratov Region ◽

Grain Productivity ◽

Control Variant ◽

The Right

Under the conditions of the Right Bank of the Saratov Region, the effect of four herbicides, two new tank mixtures and two new compositions of herbicides on the value and variability of the following indicators of soybeans: “grain yield”, “number of beans from a plant”, “the number of grains per plant", "the mass of 1000 grains", "the protein content in the grain” was studied in three field experiments using two-way variance and correlation analysis. The relationships between grain yield and elements of its structure, grain yield and protein content in grain are studied. All studied variants after application of herbicides significantly exceeded the control variant in grain yield. Options with the use of a new tank mixture of frontier optima + gezagard herbicides, frontier optima + galaxy top herbicidal compositions, hezagard + galaxy top herbicide compositions significantly exceeded the grain yield after application of herbicides. This led to a decrease in the variability of the studied indicators and changed the nature of the correlation dependence of grain productivity with other economically useful indicators of soybeans. The specific effect of the application of individual herbicides, their tank mixtures and compositions on the variability and interconnection of economically useful indicators of soybeans has been established.

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Manipulation of sunflower population density and herbicide rate for economical and sustainable weed management

ROMANIAN BIOTECHNOLOGICAL LETTERS ◽

10.25083/rbl/26.4/2751-2758 ◽

2021 ◽

Vol 26 (4) ◽

pp. 2751-2758

Author(s):

EDITA ŠTEFANIĆ ◽

SLAVICA ANTUNOVIĆ ◽

BOŽICA JAPUNDŽIĆ-PALENKIĆ ◽

DINKO ZIMA

Keyword(s):

Population Density ◽

Weed Control ◽

Crop Yield ◽

Weed Management ◽

Management Strategies ◽

Control Efficacy ◽

Economic Return ◽

Crop Density ◽

Herbicide Treatments ◽

Weed Infestation

Field study tested weed control efficacy, crop yield and economic return using various weed management strategies in sunflower growing with different population density. Treatments included four rates of PRE emergence application of S-metolachlor + fluchloridon and one POST emergence application of flumioxazin + quizalofop-pethyl. PRE-em application (1.4 + 2.4 and 1.2 + 2.0) provided at the higher crop densities (70 000) best weed control. However, PRE- em treatments with lower doses (0.8 + 1.6 and 1.0 + 1.8) and POST- em application did not maintain acceptable control of dominant weeds. Grain yield increased with the crop density, but did not statistically differ between applied herbicide treatments. Finally, the implication of this study demonstrated that sole application of tested herbicide treatments at higher crop sowing density (60 000 and 70 000) was found to be economically the best alternative strategy for reducing weed infestation and achieving a better yield.

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Tolerance and Selectivity of Cereal Species and Cultivars to Postemergence Weed Harrowing

Weed Science ◽

10.1614/ws-08-109.1 ◽

2009 ◽

Vol 57 (3) ◽

pp. 338-345 ◽

Cited By ~ 17

Author(s):

Jesper Rasmussen ◽

Helle H. Nielsen ◽

Hanne Gundersen

Keyword(s):

Grain Yield ◽

Weed Control ◽

Field Experiments ◽

Yield Loss ◽

Soil Cover ◽

Crop Damage ◽

Growth Stages ◽

Crop Tolerance ◽

Barley Cultivars ◽

Cereal Species

POST weed harrowing and other cultivation methods to control weeds in early crop growth stages may result in crop damage due to low selectivity between crop and weeds. Crop tolerance to cultivation plays an important role but it has not been clearly defined and analyzed. We introduce a procedure for analyzing crop tolerance on the basis of digital image analysis. Crop tolerance is defined as the ability of the crop to avoid yield loss from cultivation in the absence of weeds, and it has two components: resistance and recovery. Resistance is the ability of the crop to resist soil covering and recovery is the ability to recover from it. Soil covering is the percentage of the crop that has been buried because of cultivation. We analyzed data from six field experiments, four experiments with species of small grains, barley, oat, wheat, and triticale, and two experiments with barley cultivars with different abilities to suppress weeds. The order of species' tolerance to weed harrowing was triticale > wheat > barley > oat and the differences were mainly caused by different abilities to recover from soil covering. At 25% soil covering, grain yield loss in triticale was 0.5%, in wheat 2.5%, in barley 3.7%, and in oat 6.5%. Tolerance, resistance, and recovery, however, were influenced by year, especially for oat and barley. There was no evidence of differences between barley cultivars in terms of tolerance indicating that differences among species are more important than differences among cultivars. Selectivity analysis made it possible to calculate the crop yield loss due to crop damage associated with a certain percentage of weed control. In triticale, 80% weed control was associated with 22% crop soil cover on average, which reduced grain yield 0.4% on average in the absence of weeds. Corresponding values for wheat, barley, and oat were 23, 21, and 20% crop soil cover and 2.3, 3.6, and 5.1% grain yield loss.

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Integrated Weed Management Using Planting Pattern, Cultivar, and Herbicide in Dry-Seeded Rice in Northwest India

Weed Science ◽

10.1614/ws-d-13-00115.1 ◽

2014 ◽

Vol 62 (2) ◽

pp. 350-359 ◽

Cited By ~ 11

Author(s):

Gulshan Mahajan ◽

Vikas Poonia ◽

Bhagirath S. Chauhan

Keyword(s):

Grain Yield ◽

Weed Control ◽

Weed Management ◽

Field Experiments ◽

Weed Suppression ◽

Integrated Weed Management ◽

Rice Grain ◽

Planting Pattern ◽

Weed Biomass ◽

Northwest India

Field experiments were conducted in Punjab, India, in 2011 and 2012 to study the integrated effect of planting pattern [uniform rows (20-cm spacing) and paired rows (15-, 25-, and 15-cm spacing)], cultivars (PR-115 and IET-21214), and weed control treatments (nontreated control, pendimethalin 750 g ai ha−1, bispyribac-sodium 25 g ai ha−1, and pendimethalin 750 g ha−1 followed by bispyribac-sodium 25 g ha−1) on weed suppression and rice grain yield in dry-seeded rice. In the nontreated control, IET-21214 had higher grain yield than PR-115 in both planting patterns. However, such differences were not observed within the herbicide treatment. IET-21214 in paired rows, even in nontreated control, provided grain yield (4.7 t ha−1) similar to that in uniform rows coupled with the sole application of pendimethalin (4.3 t ha−1) and bispyribac-sodium (5.0 t ha−1). In uniform rows, sequential application of pendimethalin (PRE) and bispyribac-sodium (POST) provided the highest grain yield among all the weed control treatments and this treatment produced grain yield of 5.9 and 6.1 t ha−1 for PR-115 and IET-21214, respectively. Similarly, in paired rows, PR-115 in paired rows treated with sequential application of pendimethalin and bispyribac-sodium had highest grain yield (6.1 t ha−1) among all the weed control treatments. However, IET-21214 with the sole application of bispyribac-sodium produced grain yield similar to the sequential application of pendimethalin and bispyribac-sodium. At 30 days after sowing, PR-115 in paired rows coupled with pendimethalin application accrued weed biomass (10.7 g m−2) similar to the sequential application of pendimethalin and bispyribac-sodium coupled with uniform rows (8.1 g m−2). Similarly, IET-21214 with bispyribac-sodium application provided weed control similar to the sequential application of pendimethalin and bispyribac-sodium. Our study implied that grain yield of some cultivars could be improved by exploring their competitiveness through paired-row planting patterns with less use of herbicides.

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Tank Mix of Saflufenacil with Glyphosate and Pendimethalin for Broad-spectrum Weed Control in Florida Citrus

HortTechnology ◽

10.21273/horttech.21.5.606 ◽

2011 ◽

Vol 21 (5) ◽

pp. 606-615 ◽

Cited By ~ 6

Author(s):

Megh Singh ◽

Mayank Malik ◽

Analiza H.M. Ramirez ◽

Amit J. Jhala

Keyword(s):

Weed Control ◽

Weed Management ◽

Field Experiments ◽

Management Program ◽

Integrated Weed Management ◽

Control Efficacy ◽

Citrus Production ◽

Herbicide Mixture ◽

Florida Citrus ◽

Citrus Trees

Citrus (Citrus spp.) is one of the most important crops in Florida agriculture. Weed control is a major component in citrus production practices. If not controlled, weeds may compete with citrus trees for nutrients, water, and light and may also increase pest problems. Herbicides are an important component of integrated weed management program in citrus. Saflufenacil, a new herbicide registered for broadleaf weed control in citrus, can be applied alone or in a tank mix with other herbicides to improve weed control efficacy. A total of six field experiments were conducted in 2008 and 2009 to evaluate the efficacy of saflufenacil applied alone or in a tank mix with glyphosate and pendimethalin for weed control. In addition, experiments were also conducted to evaluate phytotoxicity of saflufenacil applied at different rates and time intervals in citrus. The results suggested that saflufenacil applied alone was usually effective for early season broadleaf weed control; however, weed control efficacy reduced beyond 30 days after treatment (DAT) compared with a tank mix of saflufenacil, glyphosate, and pendimethalin. For example, control of weeds was ≤70% when saflufenacil or glyphosate applied alone compared with tank mix treatments at 60 and 90 DAT. Addition of pendimethalin as a tank mix partner usually resulted in better residual weed control compared with a tank mix of saflufenacil and glyphosate, and this herbicide mixture was comparable with grower's adopted standard treatment of a tank mix of glyphosate, norflurazon, and diuron and several other tank mix treatments. Saflufenacil applied once in a season at different rates or even in sequential applications did not injure citrus trees when applied according to label directions. It is concluded that with its novel mode of action, saflufenacil tank mixed with glyphosate and pendimethalin would provide citrus growers with another chemical tool to control broadleaf and grass weeds.

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Exploring the Effects of Different Stubble Tillage Practices and Glyphosate Application Combined with the New Soil Residual Herbicide Cinmethylin against Alopecurus myosuroides Huds. in Winter Wheat

Agronomy ◽

10.3390/agronomy12010167 ◽

2022 ◽

Vol 12 (1) ◽

pp. 167

Author(s):

Miriam Hannah Messelhäuser ◽

Marcus Saile ◽

Bernd Sievernich ◽

Roland Gerhards

Keyword(s):

Winter Wheat ◽

Weed Control ◽

Weed Management ◽

Field Experiments ◽

Soil Tillage ◽

Effective Control ◽

Tillage Practices ◽

Alopecurus Myosuroides ◽

Crop Density ◽

Seedbed Preparation

Effective control of Alopecurus myosuroides Huds. (blackgrass) solely with a chemical treatment is not guaranteed anymore because populations exhibit resistance to almost all herbicide modes of action. Integrated weed management (IWM) against blackgrass is necessary to maintain high weed control efficacies in winter cereals. Four field experiments were conducted in Southwest Germany from 2018 to 2020 to control A. myosuroides with a combination of cultural and chemical methods. Stubble treatments, including flat, deep and inversion soil tillage; false seedbed preparation and glyphosate use, were combined with the application of the new pre-emergence herbicide cinmethylin in two rates in winter wheat. Average densities of A. myosuroides in the untreated control plots were up to 505 plants m−2. The combination of different stubble management strategies and the pre-emergence herbicide cinmethylin controlled 86–97% of A. myosuroides plants at the low rate and 95–100% at the high rate until 120 days after sowing. The different stubble tillage practices varied in their efficacy between trials and years. Most effective and consistent were pre-sowing glyphosate application on the stubble and stale seedbed preparation with a disc harrow. Stubble treatments increased winter wheat density in the first year but had no effect on crop density in the second year. Pre-emergence application of cinmethylin did not reduce winter wheat densities. Multiple tactics of weed control, including stubble treatments and pre-emergence application of cinmethylin, provided higher and more consistent control of A. myosuroides. Integration of cultural weed management could prevent the herbicide resistance development.

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Effect of Herbicides and Sesbaniaco- Culture on Weed Management and Grain Yield of Direct Seeded Rice Variety Khumal-4 at Khumaltar Condition, Nepal

Agronomy Journal of Nepal ◽

10.3126/ajn.v4i0.15534 ◽

2016 ◽

Vol 4 ◽

pp. 121-127

Author(s):

R K Bhattarai ◽

D D Gautam ◽

J D Ranjit ◽

B S Chauhan

Keyword(s):

Grain Yield ◽

Weed Management ◽

Field Experiments ◽

Rice Yield ◽

Block Design ◽

Rice Variety ◽

Knapsack Sprayer ◽

Rice Season ◽

Direct Seeded ◽

Hand Weeding

Field experiments were conducted at the experimental field of Agronomy Division, Khumaltar, Nepal during 2012 and 2013 to find the effect of different herbicides on weed management and grain yield of direct seeded rice. The experiment was carried out in a Randomised Complete Block Design (RCBD ) with seven treatments in three replications. Khumal-4 rice variety was used with in all the seven treatments viz; W1 = Weedy Check (no weeding) ; W2 = Farmers practice ( two hand weeding) ; W3 =Pyrazosulfuron (pre) @ 20 g a.i /ha fb (followed by ) Bispyribac (post-emergence (post) @ 25 g a. i / ha ; W4 = Pyrazosulfuron (pre) @ 20 g a.i /ha fb Bispyribac (post) @ 25 g a. i / ha fb 2, 4 –D; W5= Oxadiargyl (pre-emergence (pre) @ 90 g a.i/ha fb Bispyribac (post) @ 25 g a. i / ha; W6 = Oxadiargyl (pre) @ 90 g a.i /ha fb Bispyribac (post) @ 25 g a. i / ha fb 2, 4- D @ 500 g a .i /ha ; W7 = Sesbania (soaked) fb 2, 4- D @ 500 g a.i / ha fb one hand weeding. Rice seeds were directly sown by seed drill machine at seed rate of 30 kg/ha. All the pre emergence herbicides were sprayed on the first day of rice sowing whereas the post emergence herbicides were sown on 20 -25 days after sowing (DAS) by using a knapsack sprayer. Sesbania seed were sown at 30 kg/ha as co-culture with rice on the same day as rice was sown by broadcasting. The Sesbania was knocked down at 30 DAS using 2, 4-D.The yield of rice in 2013 was less than that of 2012 which could be due to the less rainfall and uneven rain distribution during the rice season. The results showed that among the Pyrazosulfuron (pre) @ 20 g a.i /ha fb Bispyribac (post) @ 25 g a. i / ha fb 2, 4 –D was found effective in controlling weed population , biomass and producing highest grain yield of rice 6512 kg /ha in 2012 and 3190 kg/ha in 2013 followed by the treatment Sesbania co-culture (Soaked) fb 2, 4- D @ 500 g a.i/ ha fb one and weeding giving increased rice yield of 6499 kg/ha in 2012 and 2858 kg/ha in 2013.Agronomy Journal of Nepal (Agron JN) vol. 4, Page: 121-127, 2016

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Integrated Management of Weeds in Direct-Seeded Rice in Cambodia

Agronomy ◽

10.3390/agronomy10101557 ◽

2020 ◽

Vol 10 (10) ◽

pp. 1557

Author(s):

Robert Martin ◽

Bunna Som ◽

Joel Janiya ◽

Ratha Rien ◽

Sophea Yous ◽

...

Keyword(s):

Weed Control ◽

Weed Management ◽

Rice Field ◽

Field Experiments ◽

Integrated Management ◽

Weed Suppression ◽

Crop Damage ◽

Integrated Weed Management ◽

Crop Tolerance ◽

Direct Seeded

The objective of this work was to determine the value of improved establishment methods and herbicide applications as alternatives to high seeding rates to improve weed suppression in rice. Field experiments were carried out in 2010 and 2011 to determine optimal seeding rates and seeding methods with and without weed competition in wet-seeded rice. Under wet seeding conditions, drum seeding at 80 kg ha−1 was the most profitable treatment for both weed-free and unweeded rice. Although pre-emergence herbicides are beginning to be adopted in wet-seeded rice, they are seldom used in dry direct-seeded rice in Cambodia. Experiments were carried out in 2018 and 2019 to test crop tolerance and the efficacy of butachlor, oxadiazon, pendimethalin and pretilachlor applied post-sowing and pre-emergence to dry direct-seeded rice. Oxadiazon and butachlor, with the option for a post-emergence herbicide, provided effective weed control and a high grain yield in dry direct-seeded rice. Pretilachlor did not effectively control weeds under dry seeding conditions. Although pendimethalin exhibited good weed control, crop damage was a risk in poorly prepared seedbeds which typify Cambodian rice systems. With an effective integrated weed management strategy, it might be possible to safely reduce seeding rates below 80 kg ha−1 using drum or drill seeding machines.

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