scholarly journals Survey of Missouri Pesticide Applicator Practices, Knowledge, and Perceptions

2017 ◽  
Vol 31 (2) ◽  
pp. 165-177 ◽  
Author(s):  
Mandy D. Bish ◽  
Kevin W. Bradley

The introduction of soybean and cotton traits with resistance to synthetic auxin herbicides has led to an increase in concern over the off-target movement of dicamba and 2,4-D. A direct-mail survey was sent to Missouri pesticide applicators in January of 2016 to understand current herbicide application practices and applicator knowledge and awareness of the new synthetic auxin technologies. Completed surveys were returned by 2,335 applicators, representing approximately 11% of the state’s registered pesticide applicators. Survey data reported herein provides information regarding current pesticide applicator knowledge and practices and highlights areas that need more emphasis during applicator training. Overall, survey respondents were familiar with physical drift and methods to minimize that risk. However respondents were less familiar with volatility and temperature inversions, which can each influence off-target herbicide movement. Of the 427 commercial applicators and 1,535 noncommercial applicators who answered questions regarding volatility, 81% and 74% respectively, recognized that high temperatures can contribute to a herbicide’s ability to volatilize. However, only 48% and 39% understood that a herbicide’s vapor pressure influences volatility. Answers from the survey indicate further education is needed on the synthetic auxin technologies, such as what herbicides can be used with each technology, proper methods for inspecting and cleaning spray equipment, and the importance of reading herbicide labels. When asked whether applicators were aware of the new 2,4-D-resistant and dicamba-resistant traits, 76% of 443 commercial applicators and only 40% of 1,713 noncommercial applicators selected “yes.” Additionally, survey results suggests that current methods aimed to facilitate communication among producers and applicators, such as FieldWatch and Flag the Technology, may not be successfully adopted, at least in Missouri. Findings from this survey can be utilized to enhance training of pesticide applicators in preparation for the synthetic auxin herbicide technologies.

2019 ◽  
Vol 58 (9) ◽  
pp. 1973-1992 ◽  
Author(s):  
Mandy D. Bish ◽  
Patrick E. Guinan ◽  
Kevin W. Bradley

ABSTRACTMost pesticides applied in the United States have labels that include language prohibiting application during temperature inversions. This restriction, which is well known and is followed by aerial pesticide applicators, has more recently become a focus for ground pesticide applicators. This is partially due to the recent introduction of genetically engineered soybean and cotton with tolerance to dicamba herbicide. Dicamba has been utilized for more than 50 years to control weeds in grain crops, such as corn. In 2017, dicamba was approved for use in dicamba-tolerant soybean and cotton. In 2017 and 2018, dicamba movement onto nontarget plants was substantial. As based on patterns of injury to nontolerant crops and time of applications, some of which occurred during the evening, inversions were likely contributors to off-target movement. Historically, most research on surface temperature inversions and pesticides focused on aerial applications. Research presented here focused on development of inversion profiles at atmospheric heights relevant to ground applications, which typically occur 46–107 cm above ground level (AGL). During the 2015–17 soybean growing seasons, data were collected at three heights AGL (46, 168, and 305 cm) in three soybean-producing regions of Missouri to characterize inversions. Over 600 inversions were characterized; all were nocturnal in nature. Inversions typically lasted overnight at two locations; duration varied at the third. The largest temperature difference recorded was 6°C. This research has resulted in real-time inversion monitoring that is available online to applicators (http://agebb.missouri.edu/weather/realTime/maps/index.php#temp_inversion), and the data generated can be utilized to improve accuracy of low-level inversion forecasting models.


HortScience ◽  
2021 ◽  
pp. 1-8
Author(s):  
Michele R. Warmund ◽  
David H. Trinklein ◽  
Mark R. Ellersieck ◽  
Reid J. Smeda

The use of dicamba and 2,4-D products on herbicide-tolerant crops has resulted in numerous cases of off-target movement and injury to sensitive plants, including tomato (Solanum lycopersicon L.). Two greenhouse studies were conducted to determine whether ‘Big Beef’ (‘BB’) or ‘Florida 91’ (‘FL’) tomato plants pretreated with an antitranspirant, including Moisture-Loc (ML) at 100 mL·L−1, TransFilm (TF) at 50 g·L−1, or Wilt-Pruf (WP) at 100 mL·L−1, mitigated injury from synthetic auxin herbicides. Dicamba or 2,4-D was applied at a rate corresponding to 1/200 of the manufacturer’s labeled rate of 0.56 kg ae/ha or 1.06 kg ae/ha, respectively. At 2 weeks after treatment (WAT), plants treated with ML or WP before either herbicide exhibited injury symptoms, but they were always less severe than those treated with the herbicide alone for both cultivars. However, shoot length measurements indicated that none of the antitranspirants consistently provided protection against herbicide injury at 2 WAT. By 12 WAT, ML or WP used before either herbicide increased the number of live reproductive organs compared with dicamba or 2,4-D alone for both cultivars. Floral abortion on tomato plants was also reduced when ML or WP was applied before an herbicide treatment by 12 WAT. Although WP and ML did not provide complete protection against synthetic auxin herbicide injury, the concept of using film-forming barriers may be useful in mitigating some of the short-term effects of drift on plants.


2020 ◽  
Vol 71 (12) ◽  
pp. 3701-3709 ◽  
Author(s):  
Cara L McCauley ◽  
Scott A M McAdam ◽  
Ketaki Bhide ◽  
Jyothi Thimmapuram ◽  
Jo Ann Banks ◽  
...  

Abstract The perception pathway for endogenous auxin has been well described, yet the mode of action of synthetic auxin herbicides, used for >70 years, remains uncharacterized. We utilized transcriptomics and targeted physiological studies to investigate the unknown rapid response to synthetic auxin herbicides in the globally problematic weed species Erigeron canadensis. Synthetic auxin herbicide application consistently and rapidly down-regulated the photosynthetic machinery. At the same time, there was considerable perturbation to the expression of many genes related to phytohormone metabolism and perception. In particular, auxin herbicide application enhanced the expression of the key abscisic acid biosynthetic gene, 9-cis-epoxycarotenoid deoxygenase (NCED). The increase in NCED expression following auxin herbicide application led to a rapid biosynthesis of abscisic acid (ABA). This increase in ABA levels was independent of a loss of cell turgor or an increase in ethylene levels, both proposed triggers for rapid ABA biosynthesis. The levels of ABA in the leaf after auxin herbicide application continued to increase as plants approached death, up to >3-fold higher than in the leaves of plants that were drought stressed. We propose a new model in which synthetic auxin herbicides trigger plant death by the whole-scale, rapid, down-regulation of photosynthetic processes and an increase in ABA levels through up-regulation of NCED expression, independent of ethylene levels or a loss of cell turgor.


2020 ◽  
pp. 1-15
Author(s):  
Sarah Striegel ◽  
Maxwel C. Oliveira ◽  
Nicholas Arneson ◽  
Shawn P. Conley ◽  
David E. Stoltenberg ◽  
...  

Abstract Use of synthetic auxin herbicides has increased across the midwestern United States after adoption of synthetic auxin-resistant soybean traits, in addition to extensive use of these herbicides in corn. Off-target movement of synthetic auxin herbicides such as dicamba can lead to severe injury to sensitive plants nearby. Previous research has documented effects of glyphosate on spray-solution pH and volatility of several dicamba formulations, but our understanding of the relationships between glyphosate and dicamba formulations commonly used in corn and for 2,4-D remains limited. The objectives of this research were to (1) investigate the roles of synthetic auxin herbicide formulation, glyphosate, and spray additives on spray solution pH; (2) assess the impact of synthetic auxin herbicide rate on solution pH; and (3) assess the influence of glyphosate and application time of year on dicamba and 2,4-D volatility using soybean as bioindicators in low-tunnel field volatility experiments. Addition of glyphosate to a synthetic auxin herbicide decreased solution pH below 5.0 for four of the seven herbicides tested (range of initial pH of water source, 7.45–7.70). Solution pH of most treatments was lower at a higher application rate (4× the labeled POST rate) than the 1× rate. Among all treatment factors, inclusion of glyphosate was the most important affecting spray solution pH; however, the addition of glyphosate did not influence area under the injury over distance stairs (P = 0.366) in low-tunnel field volatility experiments. Greater soybean injury in field experiments was associated with high air temperatures (maximum, >29 C) and low wind speeds (mean, 0.3–1.5 m s−1) during the 48 h after treatment application. The two dicamba formulations (diglycolamine with VaporGrip® and sodium salts) resulted in similar levels of soybean injury for applications that occurred later in the growing season. Greater soybean injury was observed after dicamba than after 2,4-D treatments.


2014 ◽  
Vol 4 (2) ◽  
pp. 54-78
Author(s):  
Petr Adamec ◽  
Marián Svoboda

This paper deals with the results of sociological survey focused on identification of the attitudes of elderly people to further education. The research was carried out in September 2010. Experience of elderly people with further education, their readiness (determination) for further education as well as their motivation and barriers in further education were also subjects of this research. Detecting elderly population’s awareness of universities of the third age and finding out their further education preferences were an integral part of the research. Research sample consisted of citizens over 55 years living in the South Moravian region. The survey results are structured by socio-demographic features e.g.: age, sex, educational attainment etc. and provide an interesting insight into the attitudes of the target group to one of the activities that contributes to improvement of their quality of life.


2020 ◽  
pp. 1-31
Author(s):  
Geoffrey P. Schortgen ◽  
Aaron J. Patton

The herbicide 2,4-D is used in a variety of cropping systems, especially in grasses since it is a selective postemergence broadleaf herbicide. However, the most common formulation (2,4-D dimethylamine) is antagonized when mixed in hard water. The objective of this research was to determine which formulations of 2,4-D or premixes of various formulations of synthetic auxin herbicides are subject to hard water antagonism. Formulations surveyed for hard water antagonism in the first experiment included 2,4-D dimethylamine, 2,4-D diethanolamine, 2,4-D monomethylamine, 2,4-D isopropylamine salt, 2,4-D choline salt, 2,4-D isooctyl ester, and 2,4-D ethylhexyl ester. Synthetic auxin formulation types in the second experiment included water-soluble, emulsifiable concentrates and emulsion-in-water. All formulations were mixed with both soft and hard water (600 mg CaCO3 L-1) and applied to dandelions to determine if antagonism occurred in hard water. Water-soluble (amine and choline) 2,4-D formulations were antagonized by hard water, but water-insoluble (ester) 2,4-D formulations were not antagonized. Similar results were found by formulation type with water-soluble synthetic auxin premixes antagonized but emulsifiable concentrates not antagonized. Further, water-soluble salt formulations were not antagonized when formulated in premixes with other synthetic auxin herbicides as an emulsion-in-water. This research demonstrates that all 2,4-D water-soluble formulations and water-soluble premixes with phenoxycarboxylic acid herbicides are subject to hard water antagonism. Formulations of 2,4-D containing emulsifying agents protect against antagonism by the water-insoluble nature of ingredients in their formulation.


2018 ◽  
Vol 32 (5) ◽  
pp. 597-602 ◽  
Author(s):  
Marcelo Zimmer ◽  
Bryan G. Young ◽  
William G. Johnson

AbstractSynthetic auxin herbicides such as 2,4-D and dicamba are often utilized to control broadleaf weeds in preplant burndown applications to soybean. Halauxifen-methyl is a new synthetic auxin herbicide for broadleaf weed control in preplant burndown applications to corn, cotton, and soybean at low use rates (5 g ae ha–1). Field experiments were conducted to evaluate efficacy and weed control spectrum of halauxifen-methyl applied alone and in mixtures with 2,4-D (560 g ae ha–1), dicamba (280 g ae ha–1), and glyphosate (560 g ae ha–1). Glyphosate-resistant (GR) horseweed was controlled with halauxifen-methyl applied alone (90% control) and in mixtures (87% to 97% control) 35 d after treatment (DAT). Common ragweed was controlled 93% with halauxifen-methyl applied alone and 91% to 97% in mixtures 35 DAT. Halauxifen-methyl applied alone resulted in poor giant ragweed control 21 DAT (73% control); however, mixtures of halauxifen-methyl with 2,4-D, dicamba, or glyphosate controlled giant ragweed (86% to 98% control). Halauxifen-methyl alone resulted in poor redroot pigweed control (62% control) 21 DAT; however, mixtures of halauxifen-methyl with dicamba, 2,4-D, or glyphosate controlled redroot pigweed (89% to 98% control). Halauxifen-methyl controls GR horseweed and common ragweed applied alone and in mixtures with other synthetic auxin herbicides and glyphosate. Furthermore, mixing 2,4-D or dicamba with halauxifen-methyl can increase the weed control spectrum in preplant burndown applications.


1993 ◽  
Vol 13 (4) ◽  
pp. 365-388 ◽  
Author(s):  
Richard Spoth ◽  
Cleve Redmond

There is a growing body of literature which argues for more research on barriers to participation in family-focused interventions, particularly among at-risk families. Following a review of research needs and issues suggested by the literature, this article presents results from a study which 1) evaluates reasons for decisions against participation in a family-focused prevention intervention project and 2) compares characteristics of intervention project participants with those of non-participants. Data on reasons for refusing participation were collected from non-participants during a recruitment telephone interview and via a mail survey. Results indicated that the most frequent reasons given for decisions against participation concerned intervention time demands and research-related requirements such as videotaping. There were no significant differences between participants and non-participants on any sociodemographic variables. Analyses of the relationships between reasons for participation refusal and sociodemographic subgroupings of non-participants, however, suggested that variations exist among these subgroups. Overall, results highlight the feasibility and importance of data collection on intervention project non-participants, both to clarify potential participation barriers and to gather data on sample representativeness.


1977 ◽  
Vol 5 (1) ◽  
pp. 40-47 ◽  
Author(s):  
Richard D. Kahoe

College freshmen personality inventories and a mail survey were used to study correlates of current and retrospective (college freshmen) conservatism among 142 former students of a religiously conservative college. A content-free aspect of conservatism, reflected by authoritarian and dogmatic personality traits, was identified, but it had greater salience for racial than for religious or legalistic attitudes. The latter attitudes were inferred to depend more on content-based aspects of conservatism — religious institutional influences made salient by an individual's intrinsic religious orientation. College freshmen religious conservatism was related to more subsequent education, but further education was strongly related to increasing liberalism of religious attitudes.


2018 ◽  
Vol 28 (1) ◽  
pp. 6-9
Author(s):  
Carl W. Coburn ◽  
Albert T. Adjesiwor ◽  
Andrew R. Kniss

Creeping bellflower (Campanula rapunculoides) is a difficult to manage weed commonly found in turfgrass and residential areas. We evaluated the efficacy of selected postemergence herbicides (glyphosate, dicamba, clopyralid, quinclorac, and triclopyr) on greenhouse-grown creeping bellflower. The experiment was conducted in Jan. 2016 and repeated in Sept. 2016. Each herbicide was applied at five rates plus a nontreated control. Clopyralid caused greater creeping bellflower biomass reduction and mortality than the other herbicides investigated. The herbicide dose required to cause 50% mortality was lowest for clopyralid [86–138 g·ha−1 acid equivalent (a.e.)] compared with dicamba (221–536 g·ha−1 a.e.), glyphosate (196–678 g·ha−1 a.e.), triclopyr (236–782 g·ha−1 a.e.), and quinclorac (>3000 g·ha−1 a.e.). Clopyralid could be an effective herbicide for managing creeping bellflower, although it is currently not registered for use in many habitats where this plant is a problematic weed.


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