Effect of Florpyrauxifen-benzyl Formulation and Rate for Waterhyacinth Control in a Mesocosm Setting

2021 ◽  
pp. 1-17
Author(s):  
Christopher R. Mudge ◽  
Gray Turnage ◽  
Michael D. Netherland

Abstract Waterhyacinth (Eichhornia crassipes) has been the focus of national legislation efforts and has been listed as noxious, invasive, potentially invasive, or prohibited by at least seven U.S. states. Auxinic herbicides are one of the most effective control methods labeled for use in aquatic sites. In the U.S., florpyrauxifen-benzyl, a synthetic auxin, was recently (2018) registered for use in aquatic sites, but limited information has been published on efficacy, especially differences between the two formulations. Therefore, the purpose of this work was to evaluate two formulations of florpyrauxifen-benzyl – suspension concentrate (SC) and emulsifiable concentrate (EC) – at three rates each (5.9, 11.8, and 23.6 g a.i. ha-1) for control of waterhyacinth under outdoor and greenhouse conditions. All rates of each florpyrauxifen-benzyl formulation reduced waterhyacinth biomass by 90 to 100% when compared to non-treated plants at five weeks after treatment (WAT). Based on plant recovery in the outdoor trial, there was some evidence that the lowest rate (5.9 g a.i. ha-1) of florpyrauxifen-benzyl SC and EC may not be as efficacious at reducing waterhyacinth biomass as the SC and EC formulations when applied at 11.8 and 23.6 g a.i. ha-1. Future work should evaluate the florpyrauxifen-benzyl rates tested in this research against waterhyacinth in field trials and/or an operational setting to confirm findings.

2013 ◽  
Vol 30 (3) ◽  
pp. 223-232 ◽  
Author(s):  
A. Cirujeda ◽  
J. Aibar ◽  
M.M. Moreno ◽  
C. Zaragoza

AbstractOpen-air crops are important in Spanish horticulture. The limited number of herbicide active ingredients in minor crops, the waste problem of polyethylene (PE) plastic mulch and the high prices of biodegradable plastics leave hand-weeding and mechanical weed control as the most viable weed control methods. Different tools have been tested in northern European countries but their performance remains unknown in the edaphoclimatic situation of southern Europe. The objective of this work was to test novel physical weed control methods on processing tomato in northeastern Spain compared with other effective control methods, i.e., plastic and paper mulches. A first sequence of field trials was established from 2005 to 2008 at Zaragoza (Spain) to select the best physical control methods out of flamer, torsion weeder, finger weeder, flex-tine harrow and brush hoe used alone or in combination. The best method was the brush hoe which was then compared from 2009 to 2011 with PE mulch, biodegradable plastic mulch and paper mulch. Flamer, flex-tine harrow, torsion weeder and finger weeder performed quite irregularly due to crusty soil conditions and needed additional tools or repeated treatments to increase weed control efficacy. The brush hoe performed best in this soil situation working at about 5 cm depth. Weed biomass reduction was higher than 80% in 6 out of 7 years and similar yield was obtained in the brushed plots compared to the yield obtained with PE, biodegradable plastic and paper mulch. The brush hoe is thus a suitable option for weed control in processing tomato while the other tools were too weak to control aggressive summer weeds in the tested conditions.


Insects ◽  
2021 ◽  
Vol 12 (6) ◽  
pp. 550
Author(s):  
Ameya D. Gondhalekar ◽  
Arthur G. Appel ◽  
Gretchen M. Thomas ◽  
Alvaro Romero

Effective control of domestic and peridomestic cockroaches requires integrated approaches that emphasize concurrent use of chemicals with alternative control tactics. An integrated pest management (IPM) approach is particularly justified in environments where satisfactory cockroach control cannot be achieved due to multiple factors including development of insecticide aversion and resistance in some cockroach species, and poor sanitation or structural issues that foster infestations. While a flurry of research effort has been devoted to study alternative tactics for cockroach control, only a few of them have been evaluated in the context of IPM programs. This review focuses on examining studies on alternative tactics that are proven efficacious, economical, and logistically feasible for their inclusion in IPM programs for important domestic and peridomestic cockroaches in the USA. Management programs that educate the public on cockroach biology, behavior, and the importance of sanitation; use of traps to monitor infestation levels; apply targeted low impact insecticides such as baits, have demonstrated a greater success for effective and sustainable control of cockroaches when compared to an insecticide-only approach. Incorporation of other alternative control methods to IPM programs will require more applied research that validates their use in real-world scenarios and demonstrates their cost-effectiveness.


2020 ◽  
Vol 10 (1) ◽  
Author(s):  
Michelle T. Fountain ◽  
Amir Badiee ◽  
Sebastian Hemer ◽  
Alvaro Delgado ◽  
Michael Mangan ◽  
...  

Abstract Spotted wing drosophila, Drosophila suzukii, is a serious invasive pest impacting the production of multiple fruit crops, including soft and stone fruits such as strawberries, raspberries and cherries. Effective control is challenging and reliant on integrated pest management which includes the use of an ever decreasing number of approved insecticides. New means to reduce the impact of this pest that can be integrated into control strategies are urgently required. In many production regions, including the UK, soft fruit are typically grown inside tunnels clad with polyethylene based materials. These can be modified to filter specific wavebands of light. We investigated whether targeted spectral modifications to cladding materials that disrupt insect vision could reduce the incidence of D. suzukii. We present a novel approach that starts from a neuroscientific investigation of insect sensory systems and ends with infield testing of new cladding materials inspired by the biological data. We show D. suzukii are predominantly sensitive to wavelengths below 405 nm (ultraviolet) and above 565 nm (orange & red) and that targeted blocking of lower wavebands (up to 430 nm) using light restricting materials reduces pest populations up to 73% in field trials.


2019 ◽  
Vol 109 (4) ◽  
pp. 571-581 ◽  
Author(s):  
Xingkai Cheng ◽  
Xiaoxue Ji ◽  
Yanzhen Ge ◽  
Jingjing Li ◽  
Wenzhe Qi ◽  
...  

Stalk rot is one of the most serious and widespread diseases in maize, and effective control measures are currently lacking. Therefore, this study aimed to develop a new biological agent to manage this disease. An antagonistic bacterial strain, TA-1, was isolated from rhizosphere soil and identified as Bacillus methylotrophicus based on morphological and biochemical characterization and 16S ribosomal RNA and gyrB gene sequence analyses. TA-1 exhibited a strong antifungal effect on the growth of Fusarium graminearum mycelium, with 86.3% inhibition at a concentration of 108 CFU per ml. Transmission electron microscopy showed that TA-1 could disrupt the cellular structure of the fungus, induce necrosis, and degrade the cell wall. Greenhouse and field trials were performed to evaluate the biocontrol efficacy of TA-1 on maize stalk rot, and the results of greenhouse experiment revealed that the bacterium significantly reduced disease incidence and disease index. Seeds treated with a 108 CFU ml−1 cell suspension had the highest disease suppression at 86.8%. Results of field trials show that seed bacterization with TA-1 could not only reduce maize stalk rot incidence but also increase maize height, stem diameter, and grain yield. The lipopeptide antibiotics were isolated from the culture supernatants of TA-1 and identified as surfactins and iturins. Consequently, B. methylotrophicus TA-1 is a potential biocontrol agent against maize stalk rot.


2008 ◽  
Vol 48 (12) ◽  
pp. 1506 ◽  
Author(s):  
T. J. Ridsdill-Smith ◽  
A. A. Hoffmann ◽  
G. P. Mangano ◽  
J. M. Gower ◽  
C. C. Pavri ◽  
...  

The redlegged earth mite, Halotydeus destructor, continues to be an intractable pest causing damage to most crop and pasture species in southern Australia. H. destructor feed on all stages of plants, but particularly damage seedlings in autumn. Research has aimed to develop new controls based on a better understanding of the biology and ecology of this pest. Chemicals remain the key tool to control H. destructor, despite the recent appearance of resistance to synthetic pyrethroids. A control package, Timerite, has been developed by which a single well-timed spray in spring can prevent H. destructor from developing diapause eggs. Field trials show this strategy provides effective control of H. destructor the following autumn, and protects plant seedlings, although mite populations build up again during winter. Non-chemical control strategies include grazing, the use of tolerant plants such as cereals, resistant legume cultivars and avoiding rotations where favourable host plants are available in the year before growing susceptible crops such as canola. Natural enemies can assist in mite control, and their numbers can be enhanced by methods including increasing landscape features like shelterbelts. Interspecific competition can occur between H. destructor and other pest mites, but the extent to which these interactions influence the structure of pest communities under different management regimes remains to be investigated.


2019 ◽  
Vol 3 (1) ◽  
pp. 44-52
Author(s):  
Eti Setyaningsih ◽  
Ari Sunandar ◽  
Anandita Eka Setiadi

ABSTRACT. Based on the results of interviews with biology teachers of SMA Muhammadiyah 1 Pontianak, that not implemented yet local potential based learning is because of limited information. This research aims to develop local potential of West Kalimantan based booklet media on biodiversity material in Grade X of SMA Muhammadiyah 1 Pontianak.. Media development of this booklet used the Brog&Gall model development method, with stages:(1) Research and data collection,(2) planning,(3) Initial product development,(4) Initial field trials,(5) initial product repairs, and (6) field trials. The results research phase (1) that the book and worksheets teacher have not shown local potential, stage (2) the designed booklet contains core competencies, basic competencies, indicators, objectives, contents, evaluations, and bibliography, stage (3) shows the validity booklets on language aspects 85.3% (very valid), material aspects 95.3% (very valid) and media aspects 90.6% (very valid), stage (4) student responses was 85,7% (very positive) and the teacher's response was 88.7% (very positive). Then stage (5) and stage (6), student responses 90.0% (very positive) and teachers 90.4% (very positive), it concluded that developed booklet media valid and received very positive response from students and teachers.


2019 ◽  
Vol 14 (01) ◽  
pp. 3-25 ◽  
Author(s):  
Anton Bekkerman ◽  
Gary W. Brester

AbstractFor many purchases, consumers often possess only limited information about product quality. Thus, observable product characteristics are used to determine expected quality levels when making purchase decisions. We use more than 1 million weekly scanner-level observations from grocery stores across ten U.S. markets between September 2009 and August 2012 to examine how consumers value a wine bottle's closure type (i.e., cork or screw cap). We focus on lower-priced wines—those with sale prices less than $30 per 750 milliliter bottle—to more accurately evaluate decisions of consumers for whom seeking additional information about wine quality is likely more costly than the benefits derived from that information. Using both pooled ordinary least squares and quantile regressions to estimate price premiums for bottles with corks or screw caps, we find that U.S. consumers are willing to pay, on average, approximately 8% more (about $1.00) for a bottle of wine that has a cork closure. In addition, we show that the size of this premium increases as wine prices decline. (JEL Classifications: D81, M31, Q11)


2015 ◽  
Vol 8 (10) ◽  
pp. 4075-4082 ◽  
Author(s):  
K. Malowany ◽  
J. Stix ◽  
A. Van Pelt ◽  
G. Lucic

Abstract. Cavity ring-down spectrometers (CRDSs) have the capacity to make isotopic measurements of CO2 where concentrations range from atmospheric (~ 400 ppm) to 6000 ppm. Following field trials, it has come to light that the spectrographic lines used for CO2 have an interference with elevated (higher than ambient) amounts of hydrogen sulfide (H2S), which causes significant depletions in the δ13C measurement by the CRDSs. In order to deploy this instrument in environments with elevated H2S concentrations (i.e., active volcanoes), we require a robust method for eliminating this interference. Controlled experiments using a Picarro G1101-i optical spectrometer were done to characterize the H2S interference at varying CO2 and H2S concentrations. The addition of H2S to a CO2 standard gas reveals an increase in the 12CO2 concentration and a more significant decrease in the 13CO2 concentration, resulting in a depleted δ13C value. Reacting gas samples containing H2S with copper prior to analysis can eliminate this effect. Models post-dating the G1101-i carbon isotope analyzer have maintained the same spectral lines for CO2 and are likely to have a similar H2S response at elevated H2S concentrations. It is important for future work with CRDS, particularly in volcanic regions where H2S is abundant, to be aware of the H2S interference on the CO2 spectroscopic lines and to remove all H2S prior to analysis. We suggest employing a scrub composed of copper to remove H2S from all gas samples that have concentrations in excess of 1 ppb.


2015 ◽  
Vol 55 (3) ◽  
pp. 294-300 ◽  
Author(s):  
Tarek Abd El-Ghafar El-Shahawy

AbstractLife cannot exist without water. Appropriate management of water, from the water’s source to its utilization, is necessary to sustain life. Aquatic weeds pose a serious threat to aquatic environments and related eco-environments. Short- and long-term planning to control aquatic weeds is extremely important. Water hyacinth,Eichhornia crassipes(Mart.) Solms, is one of the world’s worst pests with a bad reputation as an invasive weed. In this study we are seeking the possibility of using certain chemicals with a natural background, for controlling water hyacinth since there is a delicate balance that needs to be taken into account when using herbicides in water. Five compounds, namely: acetic acid, citric acid, formic acid, and propionic acid, in three concentrations (10, 15, and 20%) were applied (i.e. as a foliar application under wire-house conditions) and compared with the use of the herbicide glyphosate (1.8 kg ∙ ha−1). All of the five compounds performed well in the control of the water hyacinth. As expected, the efficacy increased as the concentration was increased from 10 to 20%. With formic and propionic acids, the plants died earlier than when the other acids or the herbicide glyphosate, were used. Acetic acid came after formic and propionic acids in terms of efficacy. Citric acid ranked last. Formic acid/propionic acid mixtures showed superior activity in suppressing water hyacinth growth especially at the rate of (8 : 2) at the different examined concentrations (3 or 5 or 10%) compared to the formic acid/acetic acid mixtures. Using the formic acid/propionic acid mixture (8 : 2; at 3%) in the open field, provided good control and confirmed the viability of these chemicals in the effective control of water hyacinth. Eventually, these chemical treatments could be used on water for controlling water hyacinth. In the future, these chemicals could probably replace the traditional herbicides widely used in this regard. These chemicals are perceived as environmentally benign for their rapid degradation to carbon dioxide and water. For maximum efficiency thorough coverage especially in bright sunlight is essential.


Author(s):  
S. A. Savelle ◽  
G. D. Garrard

The T55-L-712 turboshaft engine, used in the U.S. Army CH-47D Chinook helicopter, has been simulated using version 3.0 of the Advanced Turbine Engine Simulation Technique (ATEST) and version 1.0 of the Aerodynamic Turbine Engine Code (ATEC). The models simulate transient and dynamic engine operation from idle to maximum power and run on an IBM-compatible personal computer. ATEST is a modular one-dimensional component-level transient turbine engine simulation. The simulation is tailored to a specific engine using engine-specific component maps and an engine-specific supervisory subroutine that defines component interrelationships. ATEC is a one-dimensional, time-dependent, dynamic turbine engine simulation. ATEC simulates the operation of a gas turbine by solving the one-dimensional, time dependent Euler equations with turbomachinery source terms. The simulation uses elemental control volumes at the sub-component level (e.g. compressor stage). The paper discusses how limited information from a variety of sources was adapted for use in the T55 simulations and how commonality between the models allowed reuse of the same material. The first application of a new turbine engine model, ATEC, to a specific engine is also discussed. Calibration and operational verification of the simulations will be discussed, along with the status of the simulations.


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