Weed Control In Soybean Research Articles

Evaluation of thiencarbazone‐methyl for use in acetolactate synthase‐resistant soybean

AbstractTo combat herbicide‐resistant weeds, new options are needed to effectively rotate herbicide modes of action and slow the development of additional herbicide resistance. Thiencarbazone‐methyl (TCM), an acetolactate synthase (ALS)‐inhibiting herbicide, is currently being evaluated for preemergence (PRE) and postemergence (POST) activity on many troublesome summer annual and perennial weeds. Multiple experiments were conducted to assess the utility of this product in soybean (Glycine max) production systems. Field experiments were conducted across Arkansas in 2016 and 2017 to determine the tolerance of ALS‐resistant soybean varieties to PRE and POST applications of TCM at either 0.03 or 0.06 lb acre–1. For all locations, no significant interactions or main effects were observed for any parameters evaluated. Overall, soybean injury remained consistently low, with <3% injury at 21 days after treatment (DAT) on all ALS‐resistant varieties. However, the ALS‐susceptible variety showed high levels of injury for both PRE (75%) and POST (98%) applications at 21 DAT. Two additional experiments were conducted in 2016, 2017, and 2018 to evaluate the efficacy of PRE and POST applications of TCM in ALS/glufosinate‐resistant soybean. For PRE applications, residual activity of TCM, imazethapyr, chlorimuron, nicosulfuron, halosulfuron, and flumetsulam at labeled rates for soybean or corn were evaluated. TCM at 0.06 lb acre–1was effective in controlling ivyleaf morningglory (91 %) and broadleaf signalgrass (97%) at 21 DAT, but was not effective in controlling ALS‐resistant Palmer amaranth (58%). In the POST experiment, TCM at 0.03 or 0.06 lb acre–1was compared to imazethapyr, chlorimuron, nicosulfuron, and halosulfuron with and without glufosinate (0.5 lb acre–1). Alone, TCM produced higher control of ivyleaf morningglory (99 to 100%) and broadleaf signalgrass (94 to 99%) at 21 DAT compared to all other ALS‐inhibiting herbicides. However, TCM alone was not effective in controlling ALS‐resistant Palmer amaranth (55 to 61%) at 21 DAT, but when combined with glufosinate control increased to 95 to 99%. The results from this research suggest that TCM could have utility in soybean weed control systems due to the high level of resistance exhibited by ALS‐resistant soybean varieties and the efficacy of TCM on common soybean weed species at both the PRE and POST application timings.

Integration of Chemical and Cultural Methods for Weed Control Management in Soybean (Glycin Max. L)

A field experiment was conducted during kharif season 2012 and 2013 at Rajmata Vijayaraje Scindia Krishi Vishwa Vidhyalaya RVSKVV, College Farm Gwalior (M.P.) to asses the suiTable method for weed control in soybean. On the basis of two years pooled data results weeding twice at 20 and 40 DAS significantly highest growth, yield attributes and seed yield as compared to the un-weeded control and was at par with pendimethalin (750 g a.i./ha) + one hand weeding, trifluralin (1000 g a.i./ha) + one hand weeding at 20 DAS and imezathapyr(100 g a.i./ha) + one hand weeding at 40 DAS. These treatments also recorded lower weed dry biomassand higher weed control efficiency. Pendimethalin (750 g a.i./ha) + one hand weeding at 20 DAS resulted higher net return (` 63500) and B:C (2.58) ratio followed by trifluralin + one hand weeding and hand weeding twice at 20 and 40 DAS. In addition to hand weeding twice, pre emergence herbicide Pendimethalin (750g a,i/ha) + one hand weeding at 20 DAS can be effectively used as an alternative for controlling weeds for obtaining optimum seed yield in soybean.

Management of grass weeds with quizalofop in soybean [Glycine max (L.) Merrill

Post-emergence herbicides are useful for managing weeds in soybean fields. Use of post-emergence herbicide(s) is increasing in India because of the ease of use and control of broad spectrum of weeds. As soybean is a rainy season crop in India, weed control remains an important concern for soybean farmers. An experiment was laid out at Research Farm of Punjab Agricultural University, Ludhiana to study effect of different herbicides for control of grass weeds in soybean. Treatments comprised of post-emergence application of quizalofop 25, 37.5 and 50 g/ha, fenoxaprop 100 g/ha, weed free and unweeded control. Phyto-toxic evaluation of herbicides was carried out on succeeding wheat crop. Quizalofop 37.5–50 g/ha significantly reduced weed density and biomass of grass weeds compared to weedy check. Quizalofop 50 g/ha gave complete control (100%) of Dactyloctenium aegyptium, Digitaria sanguinalis, Acrachne racemosa and Eragrostis spp. till 40 days and > 85% till 80 days after treatment. Quizalopfop 50 g/ha recorded soybean seed yield and yield attributes similar to that of weed free check; it gave highest B:C (2.61) and net returns ($660/ha) All weed control treatments provided higher soybean seed yield compared to unweeded control. Quizalofop at all doses was safe to succeeding wheat crop.

The Effect of Nozzle Selection and Carrier Volume on Weed Control in Soybean in North Carolina

The Effect of Nozzle Selection and Carrier Volume on Weed Control in Soybean in North Carolina

Use of residual herbicides in soybean and impact on corn in succession

The weed resistance to herbicides has generated the need to adopt different management strategies, listing the tank mixture applications and use of herbicides in different modalities. In this context, it is essential to evaluate the selectivity of these herbicides associations for the crop in which the positioning is performed, as well as the effect of the residual activity of these affecting the crop sown in succession. The objective of this study was to evaluate the control efficacy and selectivity of herbicides applied in pre and post-emergence in soybeans, and the effect of the residual activity of these products on corn cultivated in succession. Two experiments were conducted in field conditions, one for evaluating the effectiveness of the herbicides associations on weed control in soybeans and another to check the selectivity of these for soybeans and the carryover effect for corn cultivated in succession. The experimental design used in both experiments was the completely randomized blocks evaluating nine treatments. All treatments presented efficacy in the control of B. pilosa, D. horizontalis, and C. echinatus. Reductions in soybean yields were observed with the application of diclosulam (25.2 g ha-1) in pre or post-emergence. The association among glyphosate + trifluralin + cloransulam (720 + 1350 + 33,6 g ha-1) caused reductions in soybean yield. None of the treatments used in soybeans affected the corn yield grown in succession.

Cultivation Systems, Vegetable Soil Covers and their Influence on the Phytosocyology of Weeds

ABSTRACT: Phytosociological studies are groups of methods that aim at the identification, composition and distribution of plant species in a community. The objective of this study was to identify and quantify the main weeds found in beans, maize and soybean cultivated in no-tillage and conventional systems. The experimental design was a randomized block one, with four replications. Experiments were conducted during three consecutive years, with summer crop (bean, maize and soybean) treatments, no-tillage system (NTS) composed by the covers, black oat, vetch and forage radish, in addition to their intercrop. In the conventional planting system (CTS), the area was left fallow in the off-season. The shoot dry matter of the covers was evaluated in each crop. The evaluated variables were: frequency, density, abundance, dry matter and the importance value index of the species in the area. Eighteen species of weeds and 12 families were identified, with Asteraceae and Poaceae families showing the highest number of individuals. The shoot dry matter production presented a difference among the covers; the cover black oat alone and intercrop with radish and vetch stood out, with the highest averages in the 3 years of the experiments. Cropping systems and different cover crops within the no-tillage system interfered in the number of encontered species. The emergence of Euphorbia heterophylla was favored, while the emergence of Lolium multiflorum was inhibited. E. heterophylla was the most encountered in the NTS areas, and its germination was negatively influenced by soil mobilization. The intercrop of black oat and vetch provided maximum weed control in soybean.

Interference Periods in Soybean Crop as Affected by Emergence Times of Weeds

ABSTRACT: Weeds emergence times modify competition with crops. Thus, the hypothesis was that the increase in weed emergence flow decreases the period prior to interference (PPI) in soybeans and increases the critical period of interference prevention (CPIP). The objective was to determine the PPI and the CPIP of weeds in soybean crops as affected by the preferred time of weeds emergence flow. Three experiments were conducted in the field in a randomized block design with four replications. The treatments were arranged in a factorial design with factor A consisting of coexistence or weed control in soybeans and factor B for eight periods (0, 7, 14, 21, 28, 35, 42 and 135 days after crop emergence (DAE)). The numbers of emerged plants and weed dry mass by genus and crop productivity were evaluated. The weed interference in culture during all the crop cycle reduces the soybean average yield 73, 94 and 89% in the first, second and third sowing times, respectively. Chemical control may be adopted at the end of PPI, which must be done at 14, 15 and 5 DAE crop, for the first, second, third times, respectively. The sowing in advance and intermediate time of recommendation increase the PPI in about 10 days, favoring the weed management in soybean crops.

Performance of Crops Grown in Succession to Soybeans Treated with Different Residual Herbicides

ABSTRACT: Herbicides with residual effect applied in soybeans may affect the productivity of late harvest crops grown in succession. Thus, the objective of this research was to evaluate the agronomic performance of adzuki bean crops, crambe, millet and palisade grass pasture grown in succession to soybean crop treated with residual herbicides, as well as assess the contribution in weed management. Four trials were conducted in field conditions at the soybean crop in the harvest and then succeeded by adzuki bean crops, crambe, millet and palisade grass as late harvest. An experimental design was adopted in a randomized block arrangement with four replications and nine treatments represented by the application of residual herbicides: imazethapyr (1.0 and 1.5 L ha-1), chlorimuron (60 and 90 g ha-1), fomesafen (1.0 and 1.5 L ha-1) and chloransulan methyl (74.6 and 71.4 g ha-1) and without herbicide control, kept in manual weeding. The herbicides were efficient in weed control in soybeans, not affecting crop yield. However, there was no residual activity of herbicides contribution in reducing infestation in the late harvest crops. The herbicides did not promote phytotoxicity to crops of crambe, beans, millet and palisadegrass pasture when they were compared with the other treatments. The beans treated with methyl chloransulan, regardless of dose, showed a higher yield. The absence of phytotoxicity to crops can be associated with rainfall incident on soybens which contributed to the dissipation of herbicides.

English

English

Efficacy of post-emergence herbicides for weed control in soybean

A field experiment was conducted at Punjab Agricultural University, Ludhiana to study the efficacy of post-emergence herbicides for weed control in soybean. The herbicides (pendimethalin, imazethapyr, imazethapyr + imazamox and quizalofop-p-ethyl) did not show any significant adverse effects on the number, dry weight and leghaemoglobin content of nodules. Application of pendimethalin 0.45 kg/ha as pre-emergence (PE) + hand weeding (HW) at 40 days after sowing (DAS) recorded significantly higher seed yield than other treatments, however, it was at par with two hand weeding. Among the herbicides, imazethapyr at 75 g/ha applied at 3 weeks after sowing (WAS) recorded significantly higher seed yield than pendimethalin 0.45 kg/ha (PE) and weedy check and was at par with imazethapyr + imazamox 70 g/ha and quizalofop-p-ethyl 50 g/ha applied at 3 WAS. Application of pendimethalin 0.45 kg/ha (PE) + HW at 40 DAS provided the highest net returns (` 49496/ha) followed by two hand weedings. However, application of post-emergence herbicides imazethapyr at 75 g/ha and imazethapyr + imazamox 70 g/ha at 3 WAS were found promising in controlling weeds, providing optimum seed yield and higher B: C ratio. In case of scarcity of labour, post-emergence herbicides can play an important role in controlling weeds effectively.

Influence of Broadcast Spray Nozzle on the Deposition, Absorption, and Efficacy of Dicamba plus Glyphosate on Four Glyphosate-Resistant Dicot Weed Species

AbstractDicamba-resistant soybean technology provides an additional site of action for POST control of herbicide-resistant broadleaf weeds in soybean but also raises concern of off-site movement and damage to sensitive crops in adjacent fields. Dicamba formulations approved for use on dicamba-resistant soybean require applicators to use nozzles producing large droplets to reduce the risk of spray-particle drift. The use of nozzles with relatively larger droplet spectra can reduce herbicide deposition on target weeds, especially if a filtering effect from the crop canopy occurs. Experiments were conducted to evaluate the influence of broadcast nozzle design on the deposition and efficacy of 280 g ha−1glyphosate plus 140 g ha−1dicamba applied POST to four herbicide-resistant weed species. The TTI11004 nozzle, the original nozzle labeled for dicamba applications on dicamba-resistant soybean, reduced deposition coverage and density on spray cards compared with the TT11004 and XR11004 nozzle. The AIXR11004 nozzle produces a very coarse droplet spectrum and did not reduce coverage on spray cards, though it did reduce deposition density. Herbicide solution deposition onto Palmer amaranth, tall waterhemp, giant ragweed, and horseweed ranged from 0.41 to 0.52, 0.55 to 0.87, 0.49 to 0.58, and 0.38 to 0.41 µl cm−2, respectively. Nozzle design and droplet spectrum did not influence the deposition of herbicide solution onto the target weed, as all nozzles were equivalent for all species and site-years. Herbicide efficacy was not influenced by nozzle design, as weed control and plant height reduction were similar for all species. The results of this experiment show that the use of the TTI11004 nozzle for dicamba applications to dicamba-resistant soybean will provide acceptable herbicide deposition and efficacy when applied under the label requirements of weed height and carrier volume.

Weed control in soybean with preemergence‐ and postemergence‐applied herbicides

The addition of effective herbicide sites of action in preemergence (PRE)‐ and postemergence (POST)‐applied programs could improve the effectiveness of weed control in soybean. Therefore, the main objective of this study was to evaluate the efficacy of several herbicides and herbicides premixes applied PRE‐only and POST‐only for control of 11 troublesome weed species in eastern Nebraska. Earn 0.5 CEUs in Integrated Pest Management by reading this article and taking the quiz at www.certifiedcropadviser.org/education/classroom/classes/497.<textboxend>

Estimation of Critical Period for Weed Control in Soybean on Agro-forestry System with Kayu Putih

Estimation of Critical Period for Weed Control in Soybean on Agro-forestry System with Kayu Putih

Weed Control in Soybean with Preemergence‐ and Postemergence‐applied Herbicides

Core Ideas Herbicide premixes provided good (>90%) broadleaf and grass weed control in Nebraska. Preemergence‐applied herbicide premixes with different sites of action will help manage resistance weeds. Preemergence‐applied herbicides should be a foundation for weed management in soybean. In the past 20 years, weed control in soybean (Glycine max) was mainly based on postemergence (POST) applications of glyphosate, which resulted in glyphosate‐resistant weeds. Herbicide‐resistant weeds warrants evaluation of new strategies for effective control. Therefore, the objective of this study was to evaluate the performance of herbicides applied preemergence (PRE) and POST on 11 agronomic weeds in eastern Nebraska. The study was conducted in 2014 and 2015 in Concord, NE. The best PRE‐applied treatments were metolachlor + imazethapyr, fomesafen + imazethapyr, flumioxazin + imazethapyr, and flumioxazin + metribuzin, which controlled broadleaf and grass weed species ≥90 and ≥80%, respectively. However, weed control with POST herbicides was more variable, ranging from 19 to 91%. The POST‐applied fomesafen and fomesafen + imazethapyr controlled ivyleaf morningglory (Ipomoea hederacea), common lambsquarters (Chenopodium album), common waterhemp (Amaranthus tuberculatus), and redroot pigweed (Amaranthus retroflexus) ≥85%. Greater soybean yields were achieved with most PRE‐applied herbicides and POST‐applied fomesafen + imazethapyr only. Metolachlor + imazethapyr, metolachlor, and fomesafen applied PRE protected soybean yields better than when applied POST. Results suggested that PRE‐applied herbicide mixtures of different sites of action are the base for controlling weeds and protecting soybean yields in eastern Nebraska.

Weed control in soybean (Glycine max L.) through resource management strategies and its influence on yield and nutrient uptake

A field experiment was conducted during kharif season of 2011 at Research Farm, Sher-e-Kashmir University of Agricultural Sciences and Technology, Chatha, Jammu to evaluate the effect of weed management prac-tices on yield and nutrient uptake of soybean utilizing different resource management strategies. The lowest weed density and dry matter of weeds was recorded with hand weeding at 15 and 35 days after sowing (DAS) which was equally effective as imazethapyr @ 75 g ha -1 (PoE) fb hoeing at 35 DAS and quizalofop-ethyl @ 40 g ha-1 (PoE) fb hoeing at 35 DAS. All weed control treatments had significant effect on yield and nutrient up-take of soybean. Among the different weed control treatments, lowest N, P and K uptake by weeds were recorded in hand-weeding (15 and 35 DAS) which was statistically at par with imazethapyr @ 75 g ha -1 fb hoeing at 35 DAS. The maximum uptake by seed and straw were recorded in weed free which was statistically at par with twice hand weeding at 15 and 35 DAS, imazethapyr @ 75 g ha-1 fb hoeing at 35 DAS and quizalofop-ethyl @ 40 g ha-1 fb hoeing at 35 DAS. The highest seed and straw yield of soybean was harvested with hand-weeding (15 and 35 DAS) followed by imazethapyr @ 75 g ha -1 fb hoeing at 35 DAS. For the first time, soybean crop has been introduced in Jammu region for research purpose. Weed management varies with agro-climatic conditions. The study would be helpful to understand weed menace in this particular climatic condition of Jammu and to manage them combinedly and efficiently.

Evaluation of efficacy of post - emergence herbicides for weed control in soybean under Marathwada region

An investigation was undertaken to evaluate the efficacy of post emergence herbicides for weed control in soybean under Marathwada region at department of Agronomy, Marathwada Agricultural University, Parbhani during the Kharif season of the year 2010. Highest number of pods plant -1 (40.62), number of grains pod -1 (2.22), seed weight plant -1 (12.18g), 100 seed weight (13.50 g), seed yield (2888 kg ha -1 ) and straw yield (3570 kg ha -1 ) were recorded in treatment (T 10 ) weed free check (2 HW+2 hoeing at 3 rd and 5 th WAS). Followed by pendimethalin PE @ 750 g a.i.ha -1 +1 HW at 30 DAS, number of pods plant -1 (38.66), number of grains pod -1 (2.18), seed weight plant -1 (10.53g), 100 seed weight (12.50g), seed yield (2820 kg ha -1 ) and straw yield (3503 kg ha -1 ). Amongst the post-emergence herbicides treatment (T 8 ) imazethapyr POE @75 g a.i.ha -1 at 21 DAS recorded highest number of pods plant -1 (38.25), number of grains pod -1 (2.14), seed weight plant -1 (09.86g), 100 seed weight (12.05g), seed yield (2705 kg ha -1 ) and straw yield (3416 kg ha -1 ) as compared to other herbicidal treatments.

Bio-efficacy of tank mixed herbicides for control of complex weed flora in soybean (Glycine max L. Merril)

A field experiment was conducted at ZARS, Jhabua (M.P.) during kharif 2014 to find out most suitable and efficient method of weed control in soybean. The experiment consisted of nine treatments laid out in randomized block design with three replications. All the weed management practices led to significant reduction in density and dry matter of weeds as compared to weedy check. Two hand weeding (20 & 40 DAS) recorded lowest weed density (4.9/ m2), weed dry matter (22.35 g/m2) with highest weed control efficiency of 59.67% and found at par with the application of Chlorimuron Ethyl @ 9gm /ha + Quizalofop-p-ethyl @ 50 g /ha (density 5.48/ m2, dry matter 26.62 g/m2 and WCE of 51.97%) and Imazethapyr @ 35 g /ha + Imazamox @ 35 g/ha (density 6.13/ m2, dry matter 26.00 g/m2 and WCE of 53.08%). Maximum yield of 1782 kg/ha was recorded in two hand weeding (20 & 40 DAS) closely followed by Chlorimuron Ethyl @ 9gm /ha + Quizalofop-p-ethyl @ 50 g /ha (1723 kg/ha) and Imazethapyr @ 35 g / ha + Imazamox @ 35 g/ha (1697 kg/ha). Reduction in soybean yield in weedy check to be recorded is 38.78 per cent when compared to weed free and 36.68 per cent in comparison to Chlorimuron Ethyl @ 9gm /ha + Quizalofopp-ethyl @ 50 g /ha. However, highest Benefit to Cost ratio is recorded in Chlorimuron Ethyl +Quizalofop-p-ethyl (3.26) closely followed by Imazethapyr + Imazamox (3.22) and Weed free (3.21).

Efficacy of flumioxazine 50% SC for weed control in soybean

The experimental research was conducted to study efficacy of flumioxazine 50% SC at various dosage for weed control in soybean over Pendimethalin 30% EC, Oxyflourfen 23.5 % EC and Chlorimuron Ethyl 25% WP. Weed control efficiency, number of pods per plant, number of seeds per pod, 100 seed weight, grain yield, haulm yield, harvest index, net return and BC ratio were evaluated. The results revealed that pre-emergence application of flumioxazine at 250 g/ha recorded higher weed control efficiency at all stages of crop growth followed by pre-emergence application of flumioxazine at 150 g/ ha. Pre-emergence application of flumioxazine at 112.5 g/ ha recorded increased yield and economic returns in soybean. Pre-emergence application of flumioxazine at 112.5 g/ ha can reduce the weed growth below the economic threshold level and increase the yield and net return and hence it provides an option to farmers to manage weeds effectively along with improved growth leading to higher productivity of soybean.

To find out suitable post-emergence herbicide for weed control in soybean under Marathwada region

An investigation was undertaken to find out suitable post emergence herbicides for weed control in soybean under Marathwada region at Department of Agronomy, Marathwada Agricultural University, Parbhani during the Kharif season of the year 2010. Highest number of pods plant -1 (40.62), seed yield (2888 kg ha -1 ), straw yield (3570 kg ha -1 ) and weed control efficiency at 40 DAS and at harvest (monocot and dicot) i.e ., 98.43, 98.78 and 96.19, 95.93 per cent, respectively were recorded in treatment (T 10 ) weed free check ( 2 HW + 2 hoeing at 3 rd and 5 th WAS). Followed by treatment T 9 pendimethalin PE @ 750 g a.i.ha -1 + 1 HW at 30 DAS, number of pods plant -1 (38.66), seed yield (2820 kg ha -1 ), straw yield (3503 kg ha -1 ) and WCE 97.10,97.23 and 89.40,85.55 per cent monocot and dicot at 40 DAS and at harvest, respectively. Weed index i.e ., lowest yield loss over weed free check was observed in treatment T 9 pendimethalin PE @ 750 g a.i.ha -1 +1 HW at 30 DAS (2.35%) and amongst the post emergence herbicides treatment (T 8 ) imazethapyr POE @ 75 g a.i.ha -1 at 21 DAS (6.33%). Amongst the post emergence herbicides treatment (T 8 ) imazethapyr POE @ 75 g a.i.ha -1 at 21 DAS were recorded highest number of pods plant -1 (38.25), seed yield (2705 kg ha -1 ), straw yield (3416 kg ha -1 ), WCE 96.02,96.42 and 86.05,81.68 per cent monocot and dicot at 40 DAS and at harvest, respectively and weed index 6.33 per cent as compared to other post herbicidal treatments.

Chemical and mechanical weed control in soybean ( Glycine max )

In this study we investigated the possibility of chemical and mechanical weed control strategies in soybean. Soybean field experiments were carried out in 2013 and 2014 in Southern Germany. Five treatments including common herbicide mixtures and four mechanical weed control treatments, implementing a harrow and a hoe, were tested at different locations. In the herbicide experiments two treatments were applied by PRE emergence herbicides (metribuzin, clomazone, dimethenamid and metribuzin, flufenacet, clomazone) and another two treatments were sprayed with a combination of PRE + POST emergence herbicides (metribuzin, flufenacet, thifensulfuron and pendimethalin, thifensulfuron, bentazone, cycloxydim). Furthermore, a POST herbicide treatment was implemented (thifensulfuron, bentazone, thifensulfuron and fluazifop-P-butyl). In the mechanical weed control experiments, treatments were: three times hoeing, PRE emergence harrowing plus three times hoeing, hoeing and harrowing in rotation or three times harrowing. In both experiments an untreated control was included. A 90% weed control efficacy and 23% yield increase was observed in the POST herbicide treatment. PRE + POST treatments resulted in 92% to 99% weed control efficiency and 15% yield increase compared to the untreated control. In the mechanical weed control experiments the combination of PRE emergence harrowing and POST emergence hoeing resulted in 82% weed control efficiency and 34% higher yield compared to the untreated control. Less weed control efficiency (72%) was observed in the harrow treatment, leading to 20% higher yield compared to the control. The suitability of both strategies for implementation in “Integrated Weed Management” has been investigated. Chemische und mechanische Unkrautkontrolle in Sojabohne ( Glycine max ) In den Jahren 2013 und 2014 wurden Feldversuche mit chemischen und mechanischen Strategien zur Unkrautkontrolle in Sojabohnen angelegt. Die chemischen Experimente setzten sich aus funf Herbizidvarianten und einer Kontrolle zusammen. In zwei der Varianten wurden Vorauflaufherbiziden mit den Wirkstoffen Metribuzin, Clomazone und Dimethenamid (Variante 1) und einer Kombination aus Metribuzin, Flufenacet und Clomazone (Variante 2) eingesetzt. Zwei weitere Varianten beinhalteten Herbizide aus dem Vor- und Nachauflauf mit den Wirkstoffen Metribuzin, Flufenacet und Thifensulfuron (Variante 3) sowie Pendimethalin, Thifensulfuron, Bentazon und Cycloxydim (Variante 4). Die funfte Variante beinhaltete eine reine Nachauflaufstrategie mit den Wirkstoffen Thifensulfuron, Bentazon, Thifensulfuron und Fluazifop-Pbutyl. In den mechanischen Experimenten wurde in Variante 1 drei Hackuberfahrten durchgefuhrt. In den weiteren Varianten wurde entweder im Vorauflauf gestriegelt und anschliesenden ebenfalls dreimalig gehackt (Variante 2), die Hacke und der Striegel im Nachauflauf abwechselnd eingesetzt (Variante 3) oder ausschlieslich der Striegel zur Unkrautkontrolle verwendet (Variante 4). Zudem wurde eine Kontrollvariante in der die Unkrauter von Hand reguliert (Variante 5) wurden und eine Variante ohne jegliche Unkrautkontrolle durchgefuhrt (Variante 6). Eine Effizienz in Bezug auf die Unkrautkontrolle von 90 % konnte in den Nachauflaufherbiziden beobachtet werden. Die Varianten mit Vorauflaufherbiziden und den Kombinationen aus Vor- und Nachauflaufherbiziden zeigten Werte von 92 % bis 99 % verglichen mit der unbehandelten Kontrolle. Der Ertragszuwachs in der Nachauflaufvariante betrug 23 % wahrend in den Varianten mit Kombination aus Vor- und Nachauflauf ein Ertragszuwachs von 15 % verglichen zu unbehandelten Kontrolle erfasst wurde. In den Versuchen mit mechanischer Unkrautkontrolle zeigte die Variante aus Vorauflaufstriegeln mit anschliesend dreimaligem Hacken im Nachauflauf einen Bekampfungserfolg von 82 % und eine Ertragssteigerung von 34 % verglichen mit der Kontrollvariante. Bei dem Einsatz des Stiegels (Variante 4) konnte eine Unkrautkontrolle von 72 % bei einer Ertragssteigerung von 20 % beobachtet werden.