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Trials for post-emergence weed control in faba beans
Get PDFAckerbohnen (Vicia faba) erfreuen sich einer wachsenden Anbaubedeutung. Allerdings ist nach Wegfall des Herbizids Basagran (Bentazon) aktuell nur eine Unkrautbekämpfung im Vorauflauf möglich. Dies ist vor allem für pfluglos wirtschaftende Betriebe problematisch, bei denen eventuell eine Mulchauflage die Wirkung der Bodenherbizide vermindert. Bei allen Betrieben könnte zudem bei einer Minderwirkung der Vorauflaufherbizide nach Frühjahrstrockenheit eine Nachbehandlung wünschenswert sein.Zu dieser Problemstellung wurde an der Fachhochschule Südwestfalen in Soest im Frühjahr 2016 zunächst ein Halbfreiland-Gefäßversuch angelegt. Dort wurden zwölf in anderen Kulturen zugelassene Nachauflaufherbizide im frühen Nachauflauf der Ackerbohnen bezüglich ihrer Verträglichkeit getestet. Es zeigten sich bei der Hälfte der eingesetzten Herbizide leichte bis deutliche Schäden an den Ackerbohnen.Im darauffolgenden Jahr 2017 wurden die als aussichtsreich identifizierten Herbizide Betanal maxxPro (Phenmedipham + Desmedipham + Ethofumesat + Lenacil) und Clearfield-Clentiga (Imazamox + Quinmerac) an zwei Standorten im Raum Soest in Freilandversuche überführt. Diese wurden sowohl auf Verträglichkeit als auch auf Wirksamkeit geprüft. Sichtbare Schäden in Form von Wuchsdepressionen und leichten Nekrosen traten dabei in den Varianten mit Betanal maxxPro an beiden Standorten auf, die sich jedoch rasch wieder auswuchsen. Die Wirksamkeit der Nachauflaufherbizide unterschied sich an beiden Standorten sehr deutlich und erreichte nicht die Wirkungssicherheit der Vorauflaufprodukte.Faba beans (Vicia faba) enjoy rising popularity. Since the herbicide Basagran (Bentazon) is no longer available, weed control is only possible as pre-emergence treatments. This is especially a problem for farms with conservation tillage, where a layer of mulch can possibly impede the effectiveness of soil herbicides. On all farms a subsequent treatment could be desirable, if spring drought makes the herbicide treatments less effective.To answer this questions the University of Applied Science in Soest / Germany carried out a pot trial under semi field conditions in spring 2016. In this trial twelve herbicides licensed in other crops were tested for their compatibility to faba beans in an early post-emergence stage. Half of the used herbicides resulted in light to distinct damage on the horse beans.In the following year 2017 the as promising identified herbicides Betanal maxxPro (Phenmedipham + Desmedipham + Ethofumesat + Lenacil) and Clearfield-Clentiga (Imazamox + Quinmerac) were transferred to field trials in two locations in the area of Soest, where they were tested for their compatibility and efficacy. Visible phytotoxic symptoms in form of depression in growing and slight necrosis were found on the variants including Betanal maxxPro in both locations, but the symptoms were outgrown fast. The efficacy of the postemergence herbicides was very different in both locations and did not reach the dependable efficacy of the pre-emergence products
Two new cereal herbicides containing new Arylex™ active: Zypar™ and Pixxaro™ EC against various Geranium species
No full textIn den letzten Jahren haben die Storchschnabel-Arten in Deutschland in verschiedenen Kulturen immer mehr an Bedeutung gewonnen. Die Gründe hierfür sind hauptsächlich der Verzicht auf wendende, intensive Bodenbearbeitung sowie eine immer kleinere Auswahl an Herbizidwirkstoffen für die Unkrautbekämpfung. Dow AgroSciences hat in den letzten Jahren zwei neue Getreideherbizide mit dem neuen Wirkstoff Arylex entwickelt: Zypar und Pixxaro EC. Beide sind sehr gut geeignet, verschiedene Storchschnabel-Arten zu bekämpfen. Dow AgroSciences hat in Deutschland Versuche initiert, um die Bekämpfungsleistung beider Produkte gegen Storchschnabel-Arten zu untersuchen und daraus Empfehlungen für die Praxis ableiten zu können. Die Versuche wurden sowohl im Gewächshaus als auch im Feld angelegt und haben gezeigt, dass beide Produkte verschiedene Storchschnabel-Arten sehr gut bekämpfen können. Hinsichtlich der Wirkung gegen unterschiedliche Storchschnabel-Arten hat sich gezeigt, dass der Kleine Storchschnabel (Geranium pussilum) von beiden am besten zu bekämpfen ist, gefolgt vom Schlitzblättrigen Storchschnabel (Geranium dissectum). Am schwierigsten zu bekämpfen scheint Weicher Storchschnabel (Geranium molle) zu sein. Dies zeigt sich besonders bei reduzierten Aufwandmengen oder bei weiter entwickelten Storchschnabel-Pflanzen. Insgesamt zeigen beide Produkte eine sehr gute Wirkung gegen verschiedene Storchschnabel-Arten und stellen daher zukünftig eine interessante Lösung für die Storchschnabel-Bekämpfung im Getreide dar.In recent years, various Geranium species have increased their significance in many important crops in Germany. The most important reason for this situation is the increased use of no-till farming as well as a smaller selection of herbicides used to control weeds. Dow AgroSciences has recently developed two cereal herbicides containing the new active Arylex™ (halauxifen-methyl), Zypar™ und Pixxaro™ EC. Dow AgroSciences initiated trials in Germany to investigate the potential of both products to control Geranium species to recommend the most effective products to farmers. Trials were carried out in greenhouses and in the field. Both products controlled various Geranium species and controlled Geranium pusillum and G. dissectum particularly well. The most difficult to control of the Geranium species was Geranium molle
CONVISO Smart - first experiences with the new sugar beet production system
Get PDFCONVISO Smart ist ein neues System zur Bekämpfung von Ungräsern und Unkräutern in Zuckerrüben. Es besteht aus der Kombination eines Herbizides mit Wirkstoffen aus der Gruppe der ALS-Hemmer (CONVISO One) und einer Zuckerrübensorte, die gegenüber diesem Herbizid tolerant ist. Durch die Kombination aus blatt- und bodenaktiven Wirkstoffen, die Unkräuter auch in größeren Entwicklungsstadien erfassen können, können die Applikationstermine des Herbizides im Gegensatz zum klassischen Zuckerrübenanbau in vielen Fällen flexibler und damit später gesetzt werden. Zusätzlich kann die Anzahl der Applikationen deutlich reduziert werden.Doch wie wirken sich die spätere Terminierung und die reduzierte Anzahl an Herbizid-Anwendungen auf das Wirkungsspektrum insgesamt aus?Hierzu wurden verschiedene Versuche durchgeführt, um u.a. die Dauer der Bodenwirkung im Vergleich zu klassischen Zuckerrübenherbiziden zu bestimmen.Die hieraus resultierenden Ergebnisse bezüglich Wirksamkeit und Dauerwirkung von CONVISO One zeigen das breite Unkrautspektrum des Produktes sowie die langanhaltende Dauerwirkung, durch die in den meisten Fällen mit nur zwei Applikationen eine Unkrautfreiheit der Zuckerrübe bis zum Reihenschluss erzielt werden kann.CONVISO Smart is a new system to control grass and dicotyledonous weeds in sugar beets. It is a combination of an ALS-inhibitor herbicide (CONVISO One) and a corresponding ALS-inhibitor tolerant sugar beet. Due to the combination of both foliar and soil active ingredients in the herbicide product, which can control weeds even at increased BBCH stages, application timing can be more flexible and numbers of application can be reduced.But what is the effect of CONVISO One on the weed spectrum and efficacy if the herbicide application is conducted later in the season in comparison to the classical sugar beet production system?A number of trials have been conducted in Germany to get an idea of the efficacy spectrum and the residual efficacy of the new herbicide.Results confirm the broad efficacy spectrum and the long residual efficacy of the product, so in most cases only two applications are needed to control weeds until row closure of the beets
1.11 Challenges to develop risk assessment schemes for Brazilian bees: multiple exposure routes
Get PDF3.8 ‘Focal species’ – can this well-known concept in higher-tier risk assessments be an appropriate approach for solitary bees?
Get PDFBumble bees and solitary bees have to be considered in addition to honey bees regarding environmental pollinator risk assessments. For solitary bees it is proposed to use Osmia cornuta (LATR., 1805) or O. bicornis (L., 1758) as test organisms. Whereas for higher-tier assessments, semi-field testing of solitary bees has been proved to obtain sound results, experience from current Osmia field studies show that exposure of adults and larvae is not necessarily the case due to the pronounced polylectic feeding behaviour. As an alternative refinement option the ‘focal species’ concept may be used, which is well-known as a kind of first step for higher tier bird and mammal risk assessments. This approach as it applies to solitary bees, as well as its needs, refinement options and limitations is presented.Bumble bees and solitary bees have to be considered in addition to honey bees regarding environmental pollinator risk assessments. For solitary bees it is proposed to use Osmia cornuta (LATR., 1805) or O. bicornis (L., 1758) as test organisms. Whereas for higher-tier assessments, semi-field testing of solitary bees has been proved to obtain sound results, experience from current Osmia field studies show that exposure of adults and larvae is not necessarily the case due to the pronounced polylectic feeding behaviour. As an alternative refinement option the ‘focal species’ concept may be used, which is well-known as a kind of first step for higher tier bird and mammal risk assessments. This approach as it applies to solitary bees, as well as its needs, refinement options and limitations is presented
3.9 Semi-field testing of the solitary bee Osmia bicornis (L., 1758) (Hymenoptera, Megachilidae) in flowering Phacelia tanacetifolia – Chances, improvements and limitations
Get PDFBased on the proposed test design of the ICPPR non-Apis working group, a semi-field (tunnel) study was conducted with the solitary bee Osmia bicornis (L., 1758) in flowering Phacelia using tunnels. Untreated crop was used as a control, and the insect growth regulator fenoxycarb as a test item which is intended to be used as reference item for this study type. To improve the design and to enhance the informative value of such studies our method deviated in three points: placing the cocoons in the tubes of the nesting units, performing additional brood assessments in two to three day intervals and increasing the application rate of the test item.Overall the results indicated that the proposed test design is suitable to perform studies on O. bicornis in Phacelia under semi-field conditions.Data on the reproduction performance, brood termination and hatching rate of the progenies show low variability between the replicates in both treatment groups. No impact on the flight activity, mortality, reproduction performance and hatching success of the progenies was observed, but an increased brood termination rate of larvae produced within the first days after application was recorded; in particular, placing the cocoons in the tubes lead to higher proportions of nesting established females. Moreover, due to the assessment of the cell production in 2 to 3 day intervals, it is possible to analyse time dependent effects on the reproductive performance, brood termination and hatching rate which can be expected by the decreasing exposure in the course of the study. And finally, it is shown that fenoxycarb is not a suitable reference item for such studies.Based on the proposed test design of the ICPPR non-Apis working group, a semi-field (tunnel) study was conducted with the solitary bee Osmia bicornis (L., 1758) in flowering Phacelia using tunnels. Untreated crop was used as a control, and the insect growth regulator fenoxycarb as a test item which is intended to be used as reference item for this study type. To improve the design and to enhance the informative value of such studies our method deviated in three points: placing the cocoons in the tubes of the nesting units, performing additional brood assessments in two to three day intervals and increasing the application rate of the test item.Overall the results indicated that the proposed test design is suitable to perform studies on O. bicornis in Phacelia under semi-field conditions.Data on the reproduction performance, brood termination and hatching rate of the progenies show low variability between the replicates in both treatment groups. No impact on the flight activity, mortality, reproduction performance and hatching success of the progenies was observed, but an increased brood termination rate of larvae produced within the first days after application was recorded; in particular, placing the cocoons in the tubes lead to higher proportions of nesting established females. Moreover, due to the assessment of the cell production in 2 to 3 day intervals, it is possible to analyse time dependent effects on the reproductive performance, brood termination and hatching rate which can be expected by the decreasing exposure in the course of the study. And finally, it is shown that fenoxycarb is not a suitable reference item for such studies
3.13 Tank mixtures of insecticides and fungicides, adjuvants, additives, fertilizers and their effects on honey bees after contact exposure in a spray chamber
Get PDFIn agriculture honey bees may be exposed to multiple pesticides. In contrast to single applications of plant protection products (PPP), the effects of tank mixtures of two or more PPP on honey bees are not routinely assessed in the risk assessment of plant protection products. However, tank mixes are often common practice by farmers. Mixtures of practically non-toxic substances can lead to synergistic increase of toxic effects on honey bees, observed for the first time in 19921 in combinations of pyrethroids and azole fungicides. 2004 Iwasa et al. already reported that ergosterol-biosynthesis-inhibiting (EBI) fungicides strongly increase the toxicity of neonicotinoids in laboratory for the contact exposure route. Furthermore, in agricultural practice additives, adjuvants and fertilizers may be added to the spray solution. For these additives usually no informations on potential side effects on bees are available when mixed with plant protection products. Therefore, it is considered necessary to investigate possible additive or synergistic impacts and evaluate potentially critical combinations to ensure protection of bees. Here, we investigated the effects on bees of combinations of insecticides, fungicides and fertilizers under controlled laboratory conditions. A spray chamber was used to evaluate effects following contact exposure by typical field application rates. Subsequently, mortality and behaviour of bees were monitored for at least 48 h following the OECD acute contact toxicity test 2143. Dependencies of synergistic effects and the time intervals between the applications of the mixing partners were evaluated.In agriculture honey bees may be exposed to multiple pesticides. In contrast to single applications of plant protection products (PPP), the effects of tank mixtures of two or more PPP on honey bees are not routinely assessed in the risk assessment of plant protection products. However, tank mixes are often common practice by farmers. Mixtures of practically non-toxic substances can lead to synergistic increase of toxic effects on honey bees, observed for the first time in 19921 in combinations of pyrethroids and azole fungicides. 2004 Iwasa et al. already reported that ergosterol-biosynthesis-inhibiting (EBI) fungicides strongly increase the toxicity of neonicotinoids in laboratory for the contact exposure route. Furthermore, in agricultural practice additives, adjuvants and fertilizers may be added to the spray solution. For these additives usually no informations on potential side effects on bees are available when mixed with plant protection products. Therefore, it is considered necessary to investigate possible additive or synergistic impacts and evaluate potentially critical combinations to ensure protection of bees. Here, we investigated the effects on bees of combinations of insecticides, fungicides and fertilizers under controlled laboratory conditions. A spray chamber was used to evaluate effects following contact exposure by typical field application rates. Subsequently, mortality and behaviour of bees were monitored for at least 48 h following the OECD acute contact toxicity test 2143. Dependencies of synergistic effects and the time intervals between the applications of the mixing partners were evaluated
Sektion 2 Herbologie / Unkrautbekämpfung / Herbizide I
Get PDF02-1 - Sinn und Unsinn ALS-Hemmer toleranter SortenJan Petersen
02-2 / 02-3 - SWOT-Analyse für das CONVISO® SMART-System im ZuckerrübenanbauNicol Stockfisch, Nelia Nause
02-4 - Reduktion der Glyphosat-Anwendungen im Ackerbau: Aus betrieblichen Anwendungsmustern lernenSabine Andert, Bärbel Gerowitt
02-5 - Umweltwirkungen des GlyphosateinsatzesJan Petersen
02-6 - Prosulfocarb - ein ,,alter\u27\u27 Wirkstoff mit Zukunft?!Christoph Krato, Hans Raffel
02-7 - Kann Herbizid Hormesis die Resistenzentwicklung in Unkräutern beeinflussen?Regina G. Belz
02-8 - Unkrautvegetation im Mais - Ergebnisse aus zwei MonitoringjahrenHeike Pannwitt, Christoph Krato, Bärbel Gerowitt02-1 - Sense and non-sense of ALS-inhibitor tolerant varietiesJan Petersen
02-2 / 02-3 - SWOT-analysis of the CONVISO® SMART-system for sugar beet cultivationNicol Stockfisch, Nelia Nause
02-4 - Reduction of glyphosate application in arable farming: Learning from on-farm use patternSabine Andert, Bärbel Gerowitt
02-5 - Environmental effects of glyphosate useJan Petersen
02-6 - Prosulfocarb - an \u27\u27old\u27\u27 compound with perspective?!Christoph Krato, Hans Raffel
02-7 - Does herbicide hormesis influence weed resistance evolution?Regina G. Belz
02-8 - Weed vegetation in maize- results from two years of monitoringHeike Pannwitt, Christoph Krato, Bärbel Gerowit