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Clearfield®-Clentiga® Runway Pack: A flexible solution for complete post-emergence weed control in winter oilseed rape
Get PDFDas seit 2015 zugelassene Herbizid Clearfield-Clentiga ist für die flexible Anwendung im Nachauflauf im Clearfield-Winterraps konzipiert und ermöglicht den vollständigen Verzicht auf die Anwendung von Bodenherbiziden im Vorauflauf/frühen Nachauflauf. Als idealer Ergänzungspartner für Clearfield-Clentiga (1,0 l/ha + 1,0 l/ha Dash E.C.) hat sich in der Praxis und in Versuchen 0,2 l/ha Runway erwiesen.Die stets sehr gute Raps-Verträglichkeit der Clearfield-Herbizide wird auch in der Kombination mit Runway nicht maßgeblich beeinflusst. Gelegentlich auftretende temporäre Blattdeformationen, wie sie für synthetische Auxin-Herbizide typisch sind, beeinträchtigen die weitere Raps-Entwicklung nicht.Das Wirkungsspektrum des Clearfield-Clentiga Runway Packs umfasst alle 28 geprüften dikotylen Unkrautarten und mit Ausnahme von Ackerfuchsschwanz auch Ungräser incl. Ausfallgetreide. Besonders hervorzuheben sind die hervorragenden Wirkungsgrade gegen alle kreuzblütigen Unkrautarten einschließlich (Nicht-Clearfield-) Ausfallraps, alle korbblütigen Unkräuter einschließlich Acker-Kratzdistel, alle doldenblütigen Unkräuter, Klettenlabkraut, Taubnessel, Vergissmeinnicht, Mohn und alle sommerannuellen Unkräuter. Auch die im Raps sehr schwer zu bekämpfenden Storchschnabel-Arten, Erdrauch, Vogelmiere, Ehrenpreis und Stiefmütterchen gehören zum Umfang sehr gut bekämpfbarer Unkräuter. Clearfield-Clentiga Runway Pack weist eine sehr gute Terminflexibilität auf: Im geprüften Bereich BBCH 11 – BBCH +14 von Raps unterschieden sich die Wirkungsgrade nur unwesentlich. Entscheidend für die vorrangig über die Blattaufnahme agierenden Wirkstoffe ist es, dass die zu bekämpfenden Unkräuter aufgelaufen sind und sich noch nicht gegenseitig abdecken bzw. noch nicht vom Raps abgeschirmt werden.Unter spezifischen Bedingungen wie z.B. hoher Besatz mit Ackerfuchsschwanz oder Storchschnabel kann Clearfield-Clentiga Runway Pack auch in Spritzsysteme z.B. mit Metazachlor-, Dimethenamid-P oder Propyzamid-haltigen Herbiziden integriert werden. Die aufgrund der guten Ausfallgetreide-Wirkung mögliche Reduktion der Einsatzintensität von FOP- und DIM-Herbiziden ist hinsichtlich des Resistenzmanagements positiv zu bewerten.Clearfield-Clentiga, which has been registered since 2015, is designed for post-emergence use in Clearfield winter oilseed rape, and allows for the complete elimination of pre-emergence/early post-emergence soil herbicides. As an ideal partner for Clearfield-Clentiga (1.0 L / ha + 1.0 L / ha Dash E.C.), 0.2 L / ha of Runway has excelled in practice and in trials.The very good crop tolerance of the Clearfield herbicides is not significantly influenced in the combination with Runway. Occasional temporary leaf deformations typical of synthetic auxin herbicides do not interfere with further rape development.The Clearfield-Clentiga Runway Pack\u27s spectrum of activity includes all 28 tested dicotyledonous weed species, and, with the exception of blackgrass, also grasses, including volunteer cereals. Particularly noteworthy are the excellent efficacy against all cruciferous weed species including (non-Clearfield) volunteer oilseed rape, all compositae weeds including thistle, all umbelliferae weeds, cleavers, deadnettle, forget-me-not, poppy and all summery weeds. But also cranesbill species, which are very difficult to control in rapeseed, fumitory, speedwell, and pansy, belong to the very well controlled weeds. Clearfield-Clentiga Runway Pack shows a very good timing flexibility: In the tested range BBCH 11 – BBCH 14 of oilseed rape, the efficiency differed only insignificantly. The decisive factor for the active substances, which predominantly act via the leaves, is, that the weeds to be controlled have to be emerged and are not yet mutually covering or are not yet screened by the crop. Under specific conditions, e.g. high infestation with blackgrass or cranesbill, Clearfield-Clentiga Runway Pack can also be used in spraying systems together with metazachlor, dimethenamid-P or propyzamide-containing herbicides. The reduction of the use of FOP and DIM herbicides, which is possible due to the good volunteer cereal control, is to be seen positively with regard to resistance management
BELKAR™ - a new herbicide for the control of a wide range of broadleaf weeds in winter oilseed rape applied post-emergence in autumn
Get PDFDie Anwendung von Vorauflaufherbiziden im Herbst ist das vorrangige Mittel der Wahl bei der Unkrautbekämpfung im Winterraps. Der Ansatz für BELKARTM ist die Verlagerung der Herbizidanwendung vom Vorauflauf in den Nachauflauf im Herbst. BELKAR kombiniert die beiden Wirkstoffe ArylexTM active und PicloramTM und enthält damit zwei nicht-ALS Wirkmechanismen. Picloram wird schon seit vielen Jahren erfolgreich im Winterraps eingesetzt, der Wirkstoff Arylex ist ein neuer Wirkstoff aus der Gruppe der Auxinähnlichen Herbizide für die Bekämpfung von wichtigen zweikeimblättrigen Unkräutern. Arylex ist der erste Vertreter der Wirkstoffgruppe der ‘Arylpicolinate‘, einer neuen Gruppe innerhalb der HRAC-Gruppe O. Der wissenschaftliche Name von Arylex ist Halauxifen-methyl‘ (DOW AGROSCIENCES, 2013). BELKAR ist das erste Herbizid in Europa, welches den Wirkstoff Arylex zur Anwendung im Winterraps enthält. Mit einer maximalen Aufwandmenge von 0.5 L/ha werden 4.8 g ae/ha Arylex und 24 g ae/ha Picloram ausgebracht. BELKAR kann sowohl im Rahmen einer Splitting-Anwendung mit 0.25 L/ha ab Kulturstadium BBCH 12-14 oder mit einer einmaligen Anwendung von 0.5 L/ha ab Kulturstadium BBCH 16 ausgebracht werden. BELKAR kontrolliert ein breites Spektrum an wichtigen Unkräutern im Winterraps, einschließlich Capsella bursa-pastoris, Centaurea cyanus, Galium aparine, Papaver rhoeas, Geranium spp., Thlaspi arvense, Matricaria spp. und Descurainia sophia. Mit BELKAR bietet sich dem Anwender in Zukunft ein neues Bekämpfungskonzept zur Unkrautbekämpfung im Nachauflauf im Winterraps. Durch die Tankmischung von BELKAR mit dem Wirkstoff Aminopyralid wird das Wirkungsspektrum auf dikotyle Unkräuter noch erweitert und somit eine wirksame Alternative zur Unkrautkontrolle im Vorauflauf geschaffen.Autumn-applied pre-emergence herbicides are currently the primary options for weed control used in winter oilseed rape. A characteristic of the new product BELKARTM herbicide is that it will be applied post-emergence in autumn. BELKAR combines both active ingredients ArylexTM Active and Picloram and therefore contains two non-ALS mode of actions. While Picloram has been widely used in oilseed rape in recent years, Arylex is a new auxinic herbicide for the post-emergence weed control of important broad-leaved weeds. Arylex is the first member of the ‘Arylpicolinate’ structural class, a new class within the HRAC Group O. The ISO common name of Arylex is ‘halauxifen-methyl’ (DOW AGROSCIENCES, 2013). BELKAR is the first herbicide in Europe containing this active for the use in winter oilseed rape. With a maximum use rate of 0.5 L/ha, the product will deliver 4.8 g ae/ha of Arylex and 24 g ae/ha of Picloram. BELKAR can be applied as a sequential application from crop stage of BBCH 12-14 at rates of 0.25 L/ha or a single application with 0.5 L/ha from crop stage BBCH 16. BELKAR provides control of a wide range of key weeds, including most important ones such as Capsella bursa-pastoris, Centaurea cyanus, Galium aparine, Papaver rhoeas, Geranium spp., Thlaspi arvense, Matricaria spp. and Descurainia sophia. With BELKAR, a post-emergence herbicide application in autumn offers a viable option for effective weed control in oilseed rape. As a new concept, the tank mix combination BELKAR with the active ingredient Aminopyralid will even more expand the weed spectrum and will provide an alternative to preemergence herbicide applications in winter oilseed rape
Does weed control by precision spray technology favour the emergence of resistance?
Get PDFTeilflächenspezifische Unkrautbekämpfung ist eine Methode für eine umweltschonende Landwirtschaft. Es ist jedoch unklar, wie diese Methode die Entwicklung von Herbizidresistenzen beeinflusst. Zur Untersuchung dieser Fragestellung wurde das von SANDT et al. (2008) für die Simulation der teilfächenspezifischen Unkrautbekämpfung entwickelte Modell durch die Hinzunahme resistenter Biotypen und ihrer genetischen Interaktion erweitert. Das Modell ermöglicht die Simulation der Entwicklung resistenter Biotypen in Abhängigkeit von der Schadschwelle, Aufwandmengen, Fruchtfolgen und der Anfangsverteilung resistenter Biotypen in der Population. Es werden Beispiele gezeigt für eine polygene Vererbung von metabolischer Resistenz unter Beteiligung von 3 Loci und damit 27 Biotypen. Erste Simulationsergebnissse deuten darauf hin, dass teilflächenspezifische Unkrautbekämpfung die Entwicklung resistenter Biotypen verzögern kann.Weed control by precision farming is recommended both by economic and ecological reasons. It is still unclear whether precision weed control favours the emergence of herbicide resistant biotypes. To investigate this, the cellular automaton model of Sandt et al. (2008) for the simulation of precision weed control was extended to resistant biotypes and their genetic interactions. The model is capable of simulating the emergence of resistant biotypes in dependence of weed control thresholds, application rates and initial distribution of biotypes. Examples are shown for the case of polygenic inheritance of resistance involving three loci and thus 27 biotypes. Preliminary simulation results hint that precision farming can delay the emergence of resistance at high weed control thresholds
Germination base temperature and relative growth rate of 13 weed species - comparing populations from two geographical origins
Get PDFEs wurden zwei Experimente durchgeführt, um die Validität von Modellparametern eines Unkraut-Simulationsmodells für norddeutsche Bedingungen zu testen. Es umfasst zurzeit Parameter zum Lebenszyklus von 25 annuellen Unkräutern, die entweder durch Experimente in der Region Burgund erhoben oder aus der Literatur entnommen wurden. Solche Parameter können sich in Populationen verschiedener geographischer Herkunft erheblich unterscheiden.Im Experiment zur Basistemperatur für die Keimung wurden norddeutsche Samen von zehn Arten untersucht. Die meisten von Ihnen wiesen Basistemperaturen auf, die ca.1.5-2.7 °C höher lagen, als die Basistemperaturen der französischen Experimente. Das Experiment zur Relativen Wachstumsrate mit 19 Arten zeigte für die meisten Arten ähnliche Werte in französischen und deutschen Populationen.Für eine Nutzung des Modells in Norddeutschland sollten die Basistemperaturen angepasst werden. Wachstumsraten können beibehalten werden, wobei für einen kleinen Teil an Arten zu klären ist, ob Unterschiede durch saisonale Verschiebungen bei Samenernte und Experiment zu erklären sind.Two experiments were conducted to test parameter validity of a simulation model under North German conditions. At the moment, the model is stocked with life cycle parameters of 25 annual weed species. These were obtained from experiments in the region Burgundy and from literature. Such parameters may vary strongly between geographical regions. Base temperature for germination was studied in one experiment for North German seeds of ten species. Mostly, base temperatures were between 1.5 and 2.7 °C higher than the parameters from French experiments. The second experiment, on Relative growth rate of 19 species, yielded similar values for most species in French and German seed populations.In respect to using the model for simulations under North German conditions, adaptations should be undertaken for the germination base temperature. Growth rates can be kept unchanged, but for some species it needs to be clarified whether differences between parameters can be explained through seasonal variations in seed collection or experiment
Aspects of a system analysis contributing to an evaluation of the CONVISO® SMART SYSTEM
Get PDFIn Feldversuchen zeigte sich, dass das Herbizid Conviso One über ein breites Wirkungsspektrum und eine lange Wirkungsdauer verfügt. Die Erwartung an das System aus Herbizid und toleranter Sorte (Conviso Smart) ist, dass typische Probleme der praxisüblichen Unkrautbekämpfung im Zuckerrübenanbau besser gelöst werden können. Damit wären Voraussetzungen geschaffen, die Anzahl an Herbizidmaßnahmen zu reduzieren und damit die Intensität des Herbizideinsatzes insgesamt zu verringern. Wie vorteilhaft das neue System für einen Zuckerrüben anbauenden Betrieb ist, ergibt sich aus dessen Unkrautsituation und damit aus den Veränderungen in den Direktkosten für Herbizide und der Anzahl eingesparter Überfahrten zur Unkrautbekämpfung.Field trials demonstrated the broad spectrum of efficacy and the long residual activity of the herbicide Conviso One. It is expected that the system consisting of a herbicide plus a herbicide-tolerant variety (Conviso Smart) will provide solutions for typical problems regarding weed control in sugar beets. This system would allow reducing the number of herbicide treatments and the overall intensity of weed control measures. The actual positive effects on a sugar beet growing farm depend on the respective weed situation, which in turn would interact with the extent of changes in direct costs for herbicides and in number of herbicide application
1.3 New industry research and approaches that could help to improve the risk assessment on bees
Get PDF1.8 Lethal and sublethal effects of several formulations of azadirachtin on IPM Impact R&D colonies of the bumblebee Bombus terrestris (Hymenoptera: Apidae)
Get PDFThe effects of different dose rates of the most important commercially available formulations of azadirachtin and technical powder of azadirachtin were tested on Bombus terrestris, using a new laboratory method on full standardised IPM Impact R&D colonies, starting with a mother queen and 20 callows. The maximum field recommended concentration (MFRC) was applied in the first series of tests through topical, oral pollen and oral sugar water treatment. A sequential dilution testing scheme was used, by decreasing the dose rate each time with 1/10 of the concentration of the previous trial, if triggered, until no significant effects were recorded any more. The survival of the mother queen and initial workers, the total number of formed workers/drones at the end of the test and the number of new born gynes and queen brood were determined as the most important end points. For the evaluation of the results the data were calculated and categorized in the IOBC side-effect classes, used for laboratory trials.This study confirms the practical experience and the previous laboratory trials that no negative toxic or sublethal effects may occur in practice with legally registered formulations of azadirachtin on Bombus terrestris while spraying this botanical insecticide at the recommended and authorised dose rates.Furthermore, during this research study it was found that an illegal formulation of azadirachtin, based on a naphta petroleum which has been withdrawn several years before the study was carried out, was used in the study of Barbosa, W.F., De Meyer, L., Guedes, R.N.C. and Smagghe, G. (2015). Analysis of two samples of this applied formulation, in EU and USA laboratories, proved that only a limited amount of azadirachtin -about half of the indicated amount- was contained, while a chlorpyrifos contamination was traced in the formulation.The effects of different dose rates of the most important commercially available formulations of azadirachtin and technical powder of azadirachtin were tested on Bombus terrestris, using a new laboratory method on full standardised IPM Impact R&D colonies, starting with a mother queen and 20 callows. The maximum field recommended concentration (MFRC) was applied in the first series of tests through topical, oral pollen and oral sugar water treatment. A sequential dilution testing scheme was used, by decreasing the dose rate each time with 1/10 of the concentration of the previous trial, if triggered, until no significant effects were recorded any more. The survival of the mother queen and initial workers, the total number of formed workers/drones at the end of the test and the number of new born gynes and queen brood were determined as the most important end points. For the evaluation of the results the data were calculated and categorized in the IOBC side-effect classes, used for laboratory trials.This study confirms the practical experience and the previous laboratory trials that no negative toxic or sublethal effects may occur in practice with legally registered formulations of azadirachtin on Bombus terrestris while spraying this botanical insecticide at the recommended and authorised dose rates.Furthermore, during this research study it was found that an illegal formulation of azadirachtin, based on a naphta petroleum which has been withdrawn several years before the study was carried out, was used in the study of Barbosa, W.F., De Meyer, L., Guedes, R.N.C. and Smagghe, G. (2015). Analysis of two samples of this applied formulation, in EU and USA laboratories, proved that only a limited amount of azadirachtin -about half of the indicated amount- was contained, while a chlorpyrifos contamination was traced in the formulation
1.19 Questionable suitability of OECD 237 protocol in risk assessment scheme?
Get PDFPersistent xenobiotics are potentially hazardous for the bee larvae despite that they are not directly exposed in contrary to adult foraging bees. The crucial phase of larval development is the first six days after hatching when young larva grows exponentially and during this phase larvae are potentially exposed to xenobiotics via diet. That is why the life cycle of honeybee is still a great challenge for scientists. OECD reflected “this need” and adopted the OECD 237 protocol (Honey bee (Apis mellifera) larval toxicity test, single exposure) on 26th July 2013. The protocol addresses the requirements formulated by the United States, Canada, and Europe to test the toxicity of chemicals compounds on larvae fed with spiked food under laboratory conditions in a tier1 strategy.Persistent xenobiotics are potentially hazardous for the bee larvae despite that they are not directly exposed in contrary to adult foraging bees. The crucial phase of larval development is the first six days after hatching when young larva grows exponentially and during this phase larvae are potentially exposed to xenobiotics via diet. That is why the life cycle of honeybee is still a great challenge for scientists. OECD reflected “this need” and adopted the OECD 237 protocol (Honey bee (Apis mellifera) larval toxicity test, single exposure) on 26th July 2013. The protocol addresses the requirements formulated by the United States, Canada, and Europe to test the toxicity of chemicals compounds on larvae fed with spiked food under laboratory conditions in a tier1 strategy
2.2 Validation of the 22-day Honey Bee Larval Toxicity, Repeated (Chronic) Exposure Study Design
Get PDFAssessing the chronic toxicity of a compound to developing honey bees (Apis mellifera L.) has proven to be a challenge since the mid-2000s. Such data are requested by global regulatory authorities so they can evaluate the risk of compounds to larval honey bees when exposure is likely to occur in the environment. Poor test performance has led to frequent study failures and data uncertainty. Here we highlight a recent effort by the Pollinator Research Task Force (PRTF)1 to validate the use of a method for evaluating the chronic toxicity of a compound (e.g., a pesticide) to an immature honey bee for use in a risk assessment. A ring test protocol was selected and based upon the current OECD guidance document No. 2392 with amendments developed at the University of Florida (Schmehl et al. 2016)3. Fifteen independent laboratories on three continents representing government, academia, and industry followed the same testing protocol to: 1) determine if test performance is robust across different geographic regions and different laboratory personnel and 2) identify limitations associated with the methodology. The control performance criteria for a valid test according to OECD GD 239 is ≥ 85% survival at the end of the larval development and ≥ 70% survival through adult emergence. Thirteen trials (81.3%) satisfied the validity criteria and the test design’s performance was determined adequate for regulatory testing. The toxic reference chemical (dimethoate) had a consistent response with a 22-day EC 50 range of 8-22 μg active substance (a.s.)/g diet. An acetone concentration at the maximum concentration allowed by the OECD GD 239 (2% acetone) was observed to be problematic to test performance. In conclusion, the ring test methods based upon the OECD GD 239 demonstrated that the repeat (chronic) exposure of a compound on developing bees can be successfully conducted. A copy of the full study report4 can be accessed here.Assessing the chronic toxicity of a compound to developing honey bees (Apis mellifera L.) has proven to be a challenge since the mid-2000s. Such data are requested by global regulatory authorities so they can evaluate the risk of compounds to larval honey bees when exposure is likely to occur in the environment. Poor test performance has led to frequent study failures and data uncertainty. Here we highlight a recent effort by the Pollinator Research Task Force (PRTF)1 to validate the use of a method for evaluating the chronic toxicity of a compound (e.g., a pesticide) to an immature honey bee for use in a risk assessment. A ring test protocol was selected and based upon the current OECD guidance document No. 2392 with amendments developed at the University of Florida (Schmehl et al. 2016)3. Fifteen independent laboratories on three continents representing government, academia, and industry followed the same testing protocol to: 1) determine if test performance is robust across different geographic regions and different laboratory personnel and 2) identify limitations associated with the methodology. The control performance criteria for a valid test according to OECD GD 239 is ≥ 85% survival at the end of the larval development and ≥ 70% survival through adult emergence. Thirteen trials (81.3%) satisfied the validity criteria and the test design’s performance was determined adequate for regulatory testing. The toxic reference chemical (dimethoate) had a consistent response with a 22-day EC 50 range of 8-22 μg active substance (a.s.)/g diet. An acetone concentration at the maximum concentration allowed by the OECD GD 239 (2% acetone) was observed to be problematic to test performance. In conclusion, the ring test methods based upon the OECD GD 239 demonstrated that the repeat (chronic) exposure of a compound on developing bees can be successfully conducted. A copy of the full study report4 can be accessed here