scholarly journals Off-target Pesticide Movement: A Review of our Current Understanding of Drift Due to Inversions and Secondary Movement

2020 ◽  
pp. 1-43
Author(s):  
Mandy Bish ◽  
Eric Oseland ◽  
Kevin Bradley
Keyword(s):  
Environmental Factors ◽  
Current Understanding ◽  
Target Movement ◽  
Herbicide Resistant ◽  
Pesticide Drift ◽  
Temperature Inversions ◽  
Radiation Cooling ◽  
Light Gaps ◽  
Review Current

Abstract Pesticide drift has been a concern since the introduction of pesticides. Historical incidences with off-target movement of 2,4-D and dichlorodiphenyltrichloroethane (DDT) increased our understanding of pesticide fate in the atmosphere related to aerial pesticide applications. More recent incidences with dicamba have brought to light gaps in our current understanding of aerial pesticide movement following ground pesticide applications. In this paper, we review current understanding of inversions and other weather and environmental factors that contribute to secondary pesticide movement and highlight questions that need to be addressed. Factors that influence volatility and terminology associated with the atmosphere, such as cool air drainage, temperature inversions, and radiation cooling will be discussed. We also present literature that highlights the need to consider the role(s) of wind in secondary drift in addition to the role in physical drift. With increased awareness of pesticide movement and more herbicide-resistant traits available than ever before, it has become even more essential that we understand secondary movement of pesticides, recognize our gaps in understanding, and advance from what is currently unknown.

scholarly journals Gasotransmitter Regulation of Ion Channels: A Key Step in O2 Sensing By the Carotid Body

Physiology ◽  
2014 ◽  
Vol 29 (1) ◽  
pp. 49-57 ◽  
Author(s):  
Nanduri R. Prabhakar ◽  
Chris Peers
Keyword(s):  
Ion Channels ◽  
Carotid Body ◽  
Physiological Responses ◽  
Current Understanding ◽  
Body Function ◽  
Arterial Blood ◽  
Carotid Bodies ◽  
Review Current ◽  
O2 Sensing

Carotid bodies detect hypoxia in arterial blood, translating this stimulus into physiological responses via the CNS. It is long established that ion channels are critical to this process. More recent evidence indicates that gasotransmitters exert powerful influences on O2 sensing by the carotid body. Here, we review current understanding of hypoxia-dependent production of gasotransmitters, how they regulate ion channels in the carotid body, and how this impacts carotid body function.

scholarly journals The Influence of Nozzle Type on Peanut Weed Control Programs

2017 ◽  
Vol 44 (2) ◽  
pp. 93-99 ◽  
Author(s):  
O.W. Carter ◽  
E.P. Prostko ◽  
J.W. Davis
Keyword(s):  
Weed Control ◽  
Palmer Amaranth ◽  
Annual Grass ◽  
Weed Species ◽  
Target Movement ◽  
Herbicide Resistant ◽  
Control Programs ◽  
The Past ◽  
Auxin Herbicides ◽  
Nozzle Type

ABSTRACT The increase in herbicide-resistant weeds over the past decade has led to the introduction of crops that are resistant to auxin herbicides. Strict application procedures are required for the use of auxin herbicides in auxin-resistant crops to minimize off-target movement. One requirement for application is the use of nozzles that will minimize drift by producing coarse droplets. Generally, an increase in droplet size can lead to a reduction in coverage and efficacy depending upon the herbicide and weed species. In studies conducted in 2015 and 2016, two of the potential required auxin nozzle types [(AIXR11002 (coarse) and TTI11002 (ultra-coarse)] were compared to a conventional flat-fan drift guard nozzles [DG11002 (medium)] for weed control in peanut herbicide systems. Nozzle type did not influence annual grass or Palmer amaranth control in non-crop tests. Results from in-crop tests indicated that annual grass control was 5% to 6% lower when herbicides were applied with the TTI nozzle when compared to the AIXR or DG nozzles. However, Palmer amaranth control and peanut yield was not influenced by coarse-droplet nozzles. Peanut growers using the coarse-droplet nozzles need to be aware of potential reduced grass control.

Magnetoconvection and the Solar Dynamo

2000 ◽  
Vol 179 ◽  
pp. 307-313
Author(s):  
Å. Nordlund ◽  
S. B. F. Dorch ◽  
R. F. Stein
Keyword(s):  
Magnetic Fields ◽  
Numerical Simulations ◽  
Convection Zone ◽  
Current Understanding ◽  
Solar Dynamo ◽  
Stable Layer ◽  
Strong Magnetic Fields ◽  
Stellar Convection ◽  
Convective Motions ◽  
Review Current

AbstractWe review current understanding of the interaction of magnetic fields with convective motions in stellar convection zones. Among the most exciting recent results is the discovery that magnetic fields need not primarily be confined to the stable layer below the convection zone; numerical simulations have shown that surprisingly, strong magnetic fields can be maintained in the interior of the convection zone.

Effect of Environmental Factors on Germination and Emergence of Aryloxyphenoxy Propanoate Herbicide-Resistant and -Susceptible Asia Minor Bluegrass (Polypogon fugax)

Weed Science ◽  
2015 ◽  
Vol 63 (3) ◽  
pp. 669-675 ◽  
Author(s):  
Wei Tang ◽  
Xiaoyan Xu ◽  
Guoqiang Shen ◽  
Jie Chen
Keyword(s):  
Environmental Factors ◽  
Ph Value ◽  
Germination Percentage ◽  
Asia Minor ◽  
Burial Depth ◽  
Effective Management ◽  
Herbicide Resistant ◽  
Nacl Concentration ◽  
Emergence Percentage ◽  
Alternating Temperature

The influence of environmental factors on germination and emergence of aryloxyphenoxy propanoate herbicide-resistant (AR) and -susceptible (AS) Asia Minor bluegrass were studied in laboratory and greenhouse experiments. Seeds were collected from AR and AS plants cultivated in separate greenhouses under the same environmental conditions. The results revealed that optimum temperatures for the germination of AS biotype were 10 to 25 C or alternating temperature of 15/5 to 30/20 C and light was not necessary. However, maximum germination occurred at 10 C or 15/5 C, and no germination occurred above 15 C or 25/15 C for the AR biotype. The AS Asia Minor bluegrass was consistently more tolerant to environmental stress, as evidenced by their greater germination at same pH value, osmotic potential, and NaCl concentration at 15/5 C compared to the AR biotype. Higher emergence rates were obtained when seeds were sown on the surface of soil for both biotypes. Emergence percentage of the AR biotype was below 14% when buried, whereas the AS biotype had 20% emergence at 2.5 cm burial depth. It is concluded that several environmental factors affect the germination of Asia Minor bluegrass, and the AS biotype showed higher germination percentage and a wider adaptive range under same treatments compared with the AR biotype. Due to the reduced emergence at depth, deep tillage could be an effective management to reduce AR Asia Minor bluegrass infestation in the following crop.

scholarly journals The Galactic Population and Birth Rate of Radio Pulsars

2004 ◽  
Vol 218 ◽  
pp. 105-112 ◽  
Author(s):  
D. R. Lorimer
Keyword(s):  
Preliminary Analysis ◽  
Birth Rate ◽  
Current Understanding ◽  
Selection Effects ◽  
Radio Pulsars ◽  
Galactic Population ◽  
Review Current

We review current understanding of the underlying, as opposed to the observed, pulsar population. The observed sample is heavily biased by selection effects, so that surveys see less than 10% of all potentially observable pulsars. We compare various techniques used to correct the sample for these biases. By far the most significant recent development has been the discovery of over 700 pulsars in the Parkes Multibeam (PM) survey. This new sample is far less affected by selection effects and we use it to make a preliminary analysis of the Galactic pulsar distribution, finding further evidence for a deficit of pulsars in the inner Galaxy.

Identification of environmental factors that influence the likelihood of off‐target movement of dicamba

2020 ◽  
Vol 76 (9) ◽  
pp. 3282-3291 ◽  
Author(s):  
Eric Oseland ◽  
Mandy Bish ◽  
Larry Steckel ◽  
Kevin Bradley
Keyword(s):  
Environmental Factors ◽  
Target Movement

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
Keyword(s):  
Mail Survey ◽  
Further Education ◽  
Herbicide Application ◽  
Target Movement ◽  
Pesticide Applicator ◽  
Synthetic Auxin ◽  
Survey Results ◽  
Auxin Herbicides ◽  
Pesticide Applicators ◽  
Temperature Inversions

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.

Photosynthesis and productivity.

2021 ◽  
pp. 223-248
Author(s):  
Vinod K. Singh ◽  
Manoj K. Soni
Keyword(s):  
Environmental Factors ◽  
Fruit Quality ◽  
Environmental Conditions ◽  
Water Availability ◽  
Growth Yield ◽  
Current Understanding ◽  
Future Research ◽  
Maximum Productivity ◽  
Temperature Water

Abstract Knowledge on the responses of guava to environmental factors such as light, temperature, water availability and CO2 concentration is essential to determine the effect of suboptimal environmental conditions and to manage the crop for maximum productivity. This chapter aims to highlight the current understanding and the possible effects of environmental factors on the whole physiology of guava trees as expressed by growth, yield, fruit quality and photosynthetic features. Possible areas of future research are also suggested.

Sign in / Sign up

Export Citation Format

Share Document