Impact of Drift Rates of Imazethapyr and Low Carrier Volume on Non-Clearfield Rice

2012 ◽  
Vol 26 (2) ◽  
pp. 236-242 ◽  
Author(s):  
Justin B. Hensley ◽  
Eric P. Webster ◽  
David C. Blouin ◽  
Dustin L. Harrell ◽  
Jason A. Bond
Keyword(s):  
Plant Height ◽  
Crop Yield ◽  
Field Studies ◽  
Ratoon Crop ◽  
Clearfield Rice ◽  
Spray Volume ◽  
The One ◽  
Carrier Volume ◽  
Herbicide Drift ◽  
Crop Maturity

Field studies were conducted near Crowley, LA, in 2005 through 2007 to evaluate the effects of simulated herbicide drift on ‘Cocodrie’ rice. Each application was made with the spray volume varying proportionally to herbicide dosage based on a constant spray volume of 234 L ha−1and an imazethapyr rate of 70 g ai ha−1. The 6.3%, 4.4 g ha−1, herbicide rate was applied at a spray volume of 15 L ha−1and the 12.5%, 8.7 g ha−1, herbicide rate was applied at a spray volume of 29 L ha−1. An application of imazethapyr at one-tiller, panicle differentiation (PD), and boot resulted in increased crop injury compared with the nontreated rice. The most injury observed occurred on rice treated at the one-tiller timing. Imazethapyr at one-tiller, PD, and boot reduced plant height at harvest and primary and total (primary plus ratoon) crop yield, with the greatest reduction in primary crop yield resulting from imazethapyr applied at boot. Imazethapyr did not affect rice treated at primary crop maturity.

Response of Rice to Drift Rates of Glyphosate Applied at Low Carrier Volumes

2013 ◽  
Vol 27 (2) ◽  
pp. 257-262 ◽  
Author(s):  
Justin B. Hensley ◽  
Eric P. Webster ◽  
David C. Blouin ◽  
Dustin L. Harrell ◽  
Jason A. Bond
Keyword(s):  
Plant Height ◽  
Crop Yield ◽  
Field Studies ◽  
Crop Injury ◽  
Total Crop ◽  
Spray Volume ◽  
The One ◽  
Herbicide Drift ◽  
Crop Maturity

Field studies were conducted near Crowley, LA in 2005 through 2007 to evaluate the effects of simulated herbicide drift on ‘Cocodrie' rice. Each application was made with the spray volume varying proportionally to herbicide dosage based on a constant spray volume of 234 L ha−1 and a glyphosate rate of 863 g ae ha−1. The 6.3%, 54–g ha−1, herbicide rate was applied at a spray volume of 15 L ha−1, and the 12.5%, 108–g ha−1, herbicide rate was applied at a spray volume of 29 L ha−1. Compared with the nontreated, glyphosate applied at one tiller, panicle differentiation (PD), and boot resulted in increased crop injury. The greatest injury was observed on rice treated at the one-tiller timing. Applications of glyphosate at one tiller, PD, and boot reduced plant height at harvest and primary and total crop yield. Rice treated at primary crop maturity was not affected by glyphosate applications.

Rice Crop Response to Simulated Drift of Imazamox

2016 ◽  
Vol 30 (1) ◽  
pp. 99-105 ◽  
Author(s):  
Eric P. Webster ◽  
Justin B. Hensley ◽  
David C. Blouin ◽  
Dustin L. Harrell ◽  
Jason A. Bond
Keyword(s):  
Plant Height ◽  
Crop Yield ◽  
Field Studies ◽  
Growth Stages ◽  
Ratoon Crop ◽  
Physiological Maturity ◽  
Yield Increase ◽  
Spray Volume ◽  
The One ◽  
Herbicide Drift

Field studies were conducted near Crowley, LA, to evaluate the effects of simulated herbicide drift on ‘Cocodrie' rice. Each treatment was made with the spray volume varying proportionally to herbicide dosage based on a spray volume of 234 L ha−1and an imazamox rate of 44 g ai ha−1. The 6.3%, 2.7-g ha−1, herbicide rate was applied at a spray volume of 15 L ha−1and the 12.5%, 5.5-g ha−1, herbicide rate was applied at a spray volume of 29 L ha−1. Rice was treated at the one-tiller, panicle differentiation, boot, and physiological maturity growth stages. Injury was observed with imazamox applied at the one-tiller timing. Injury was not observed until 21 and 28 d after treatment (DAT) when imazamox was applied at the panicle differentiation and boot timings. The greatest reduction in plant height resulted from applications at the one-tiller timing at 7 and 14 DAT; however, when evaluated at harvest, plant height was reduced no more than 10%. Imazamox, averaged over rate, applied to rice at the boot timing reduced primary crop yield 66% compared with the nontreated. Applications at the boot timing resulted in an increased ratoon crop yield; however, the yield increase did not compensate for the loss in the primary crop yield.

Impact of Off-Site Deposition of Glufosinate to Non-Clearfield Rice

2015 ◽  
Vol 29 (2) ◽  
pp. 207-216 ◽  
Author(s):  
Eric P. Webster ◽  
Justin B. Hensley ◽  
David C. Blouin ◽  
Dustin L. Harrell ◽  
Jason A. Bond
Keyword(s):  
Growth Stage ◽  
Rice Yield ◽  
Field Studies ◽  
Seedling Vigor ◽  
Ratoon Crop ◽  
Boot Stage ◽  
Crop Injury ◽  
Clearfield Rice ◽  
Spray Volume ◽  
Herbicide Drift

Field studies were conducted near Crowley, LA to evaluate the effects of simulated herbicide drift on ‘Cocodrie' rice. Each treatment was made with the spray volume varying proportionally to herbicide dosage based on a spray volume of 234 L ha−1and a glufosinate rate of 493 g ai ha−1. The 6.3%, 31 g ha−1, herbicide rate was applied at a spray volume of 15 L ha−1and the 12.5%, 62 g ha−1, herbicide rate was applied at a spray volume of 29 L ha−1. Glufosinate applied at one-tiller, panicle differentiation (PD) growth stage, and boot resulted in crop injury at 7 and 14 d after treatment. At 21 and 28 d after treatment, crop injury was still evident but was less than 10%. Glufosinate applied at one-tiller resulted in plant height reductions of 4 to 6%; however, at harvest, height reductions were 1% or less. Glufosinate applied to rice in the boot stage had lower rice yield in the primary crop, but no difference was observed in the ratoon crop. Harvested seed from the primary crop germinated 7 to 11% less than the nontreated when rice was treated with 31 and 62 g ha−1of glufosinate. Seedling vigor was reduced when treated with 31 and 62 g ha−1of glufosinate.

scholarly journals Carrier Volume and Nozzle Effect on 2,4-D and Glufosinate Performances in Hazelnut Sucker Control

HortScience ◽  
2020 ◽  
Vol 55 (11) ◽  
pp. 1848-1852
Author(s):  
Larissa Larocca de Souza ◽  
Marcelo L. Moretti
Keyword(s):  
Dry Weight ◽  
Field Studies ◽  
Corylus Avellana ◽  
Spray Drift ◽  
Spray Nozzle ◽  
Drift Field ◽  
Spray Volume ◽  
Carrier Volume ◽  
Nozzle Type ◽  
Flat Fan Nozzle

Hazelnut (Corylus avellana L.) basal sprouts, or suckers, are removed to train trees as a single trunk, facilitating mechanization. Suckers are routinely controlled with herbicides, often by using nozzles that generate fine droplets and spray volumes as high as 934 L·ha−1, making spray drift a concern. Spray nozzle type and carrier volume can impact herbicide efficacy and drift. Field studies compared the efficacy of 2,4-D and glufosinate in controlling suckers when applied with a flat-fan nozzle, producing fine droplets, to a TeeJet air-induction nozzle, producing ultra-coarse droplets. These nozzles were evaluated at 187 and 374 L·ha−1. Nozzle and carrier volume did not affect the efficacy of 2,4-D based on control, sucker height, or dry weight. The efficacy of glufosinate was unaffected by nozzle type or spray volume in most evaluations. These results indicate that hazelnut suckers can be effectively controlled using drift-reduction nozzles with lower carrier volumes (187 L·ha−1). Drift-reduction nozzles, coupled with lower spray volume, can maintain herbicide efficacy, minimize drift risk, and reduce cost.

scholarly journals Damage to lemon tree caused by simulated drift of herbicides

2020 ◽  
Vol 19 (3) ◽  
pp. 319-328
Author(s):  
Leandro Galon ◽  
Clevison Luis Giacobbo ◽  
André Ricardo Zeist ◽  
Marlon Ouriques Bastiani ◽  
Doralice Lobato de Oliveira Fischer ◽  
...  
Keyword(s):  
Experimental Design ◽  
Plant Height ◽  
Commercial Product ◽  
Sensitive Species ◽  
Trunk Diameter ◽  
Crown Volume ◽  
The One ◽  
Herbicide Drift ◽  
Lemon Tree

The use of herbicides, in particular clomazone and glyphosate, applied in isolation or in a tank mix, is very common in rice, soybeans, corn and sugarcane fields and the drift of these herbicides can cause damage in sensitive species grown nearby. The purpose of this work was to evaluate the effects of the simulated drift of clomazone and glyphosate applied in an isolated way or mixed in a spray on lemon tree plants. The experiment was installed in a greenhouse in pots with a capacity of 15 L containing sieved soil and an experimental design of randomized blocks was adopted, arranged in a 3 x 5 factorial scheme, with four replications. Plants with two years of development were used. The treatments tested were, clomazone, glyphosate and both mixed, and the decreasing doses of the recommended commercial product: 100, 75, 50, 25 and 0% to simulate herbicide drift. Was evaluated variables, phytotoxicity at 14, 28, 46 and 100 days after application of treatments; plant height, crown volume, the trunk diameter of the rootstock, trunk diameter of the graft and trunk diameter at the grafting point at 0 and 100 days after application of treatments; and liquid assimilation of CO2 at 10 and 60 days after application of treatments. Among the tested herbicides, the one that presented the highest phytotoxicity and the lowest liquid assimilation of CO2 in lemon tree plants was the glyphosate + clomazone mixture. Increases in trunk diameter of the rootstock, grafting point, graft and crown volume did not show significant effects with simulated drift. The plant height presented a greater reduction with the increase of the herbicide doses, mainly glyphosate. That there are considerable losses in lemon tree plants when herbicide drift occurs, mainly by glyphosate and its mixture with clomazone.

Snap Bean Tolerance to Herbicides in Ontario

2004 ◽  
Vol 18 (4) ◽  
pp. 962-967 ◽  
Author(s):  
Kristen E. McNaughton ◽  
Peter H. Sikkema ◽  
Darren E. Robinson
Keyword(s):  
Plant Height ◽  
Crop Yield ◽  
Weed Management ◽  
Yield Loss ◽  
Treatment Plant ◽  
Field Studies ◽  
Management Tools ◽  
Snap Bean ◽  
Bean Yield

Snap bean was evaluated for sensitivity to a number of herbicides in field studies conducted during a 2-yr period in Exeter, ON. Preemergence (PRE) applications of metolachlor (1,600 and 3,200 g ai/ha), imazethapyr (75 and 150 g ai/ha), and clomazone plus metobromuron (840 + 1,000 g ai/ha and 1,680 + 2,000 g/ha) were evaluated for visual injury at 7, 14, and 28 d after emergence. Postemergence (POST) applications of imazamox plus fomesafen (25 + 200 g ai/ha and 50 + 400 g/ha), quizalofop-P (72 and 144 g ai/ha), and clethodim (90 and 180 g ai/ha) also were evaluated for visual injury 7, 14, and 28 d after treatment. Plant height and crop yield were assessed for all treatments. Visual injury, stunting, and yield loss were not observed in the metolachlor treatments. Imazethapyr (150 g/ha) caused stunting and reduced snap bean yield in both study years. Clomazone plus metobromuron (1,680 + 2,000 g/ha) injured and stunted snap bean in both years of the study and reduced yield in 2000. Imazamox plus fomesafen (50 + 400 g/ha) injured snap bean in both years but only reduced yield in 2000. Quizalofop-P injured snap bean but did not reduce plant height or yield. Clethodim did not injure, stunt, or reduce yield of snap bean. Metolachlor (PRE), imazamox plus fomesafen (POST), quizalofop-P (POST), and clethodim (POST) have excellent potential as weed management tools in snap bean in Ontario.

General practitioners and clinical pharmacology

1989 ◽  
Vol 4 (4) ◽  
pp. 241-244
Author(s):  
P. Lemoine
Keyword(s):  
Clinical Pharmacology ◽  
General Practitioners ◽  
Field Studies ◽  
Discussion Group ◽  
Group Method ◽  
Study Group ◽  
Test Drug ◽  
Monthly Basis ◽  
One Year ◽  
The One

SummaryIt is difficult to undertake field studies with non marketed psychotropic drugs because of two apparently contradictory conditions : on the one hand, the methodology has to be rigorously controlled, and on the other hand, such studies have to be carried out in their future environment by general practitioners (GPs). Bearing in mind the lack of training and experience regarding this kind of approach, the author adopted a discussion group method according to the techniques developed by M. Balint. The study group comprised five GPs, a clinical pharmacology expert and a doctor from the pharmaceutical laboratory which had developed the test drug. These persons met on a monthly basis over a one year period. In the present paper, the author indicates the benefits of such a methodology, based on six years’ experience and several trials, with special emphasis placed on the pedagogical aspects.

scholarly journals Reproduction and biomarker responses of Eisenia fetida after exposure to imidacloprid in biochar-amended soil

Biochar ◽  
2021 ◽  
Author(s):  
Ngitheni Winnie-Kate Nyoka ◽  
Ozekeke Ogbeide ◽  
Patricks Voua Otomo
Keyword(s):  
Eisenia Fetida ◽  
Field Studies ◽  
Application Rate ◽  
Land Application ◽  
Acetylcholinesterase Inhibition ◽  
Beneficial Effects ◽  
Pesticide Pollution ◽  
The One ◽  
The Impact ◽  
Amended Soil

AbstractTerrestrial and aquatic ecosystems are increasingly threatened by pesticide pollution resulting from extensive use of pesticides, and due to the lack of regulatory measures in the developing world, there is a need for affordable means to lessen environmental effects. This study aimed to investigate the impact of biochar amendment on the toxicity of imidacloprid to life-cycle parameters and biomarker responses of the earthworm Eisenia fetida. E. fetida was exposed to 10% biochar-amended and non-amended OECD artificial soils spiked with 0, 0.75, 1.5, 2.25 and 3 mg imidacloprid/kg for 28 days. An LC50 of 2.7 mg/kg was only computed in the non-amended soil but not in the biochar-amended soil due to insignificant mortality. The EC50 calculated in the non-amended soil (0.92 mg/kg) for reproduction (fertility) was lower than the one computed in the biochar amended (0.98 mg/kg), indicating a decrease in toxicity in the biochar-amended substrate. Significant weight loss was observed at the two highest imidacloprid treatments in the non-amended soil and only at the highest treatment in the biochar-amended substrate, further highlighting the beneficial effects of biochar. Catalase activity decreased significantly at the two highest concentrations of non-amended soil. Yet, in the amended soil, the activity remained high, especially in the highest concentration, where it was significantly higher than the controls. This indicated more severe oxidative stress in the absence of biochar. In all non-amended treatments, there was a significant acetylcholinesterase inhibition, while lower inhibition percentages were observed in the biochar-amended soil. In most endpoints, the addition of biochar alleviated the toxic effects of imidacloprid, which shows that biochar has the potential to be useful in soil remediation. However, there is still a need for field studies to identify the most effective application rate of biochar for land application.

scholarly journals A methodology to conduct wind damage field surveys for high-impact weather events of convective origin

2020 ◽  
Vol 20 (5) ◽  
pp. 1513-1531 ◽  
Author(s):  
Oriol Rodríguez ◽  
Joan Bech ◽  
Juan de Dios Soriano ◽  
Delia Gutiérrez ◽  
Salvador Castán
Keyword(s):  
Field Studies ◽  
High Impact ◽  
Strong Wind ◽  
Field Surveys ◽  
Weather Events ◽  
Straight Line ◽  
High Impact Weather ◽  
Strong Winds ◽  
Wind Events ◽  
The One

Abstract. Post-event damage assessments are of paramount importance to document the effects of high-impact weather-related events such as floods or strong wind events. Moreover, evaluating the damage and characterizing its extent and intensity can be essential for further analysis such as completing a diagnostic meteorological case study. This paper presents a methodology to perform field surveys of damage caused by strong winds of convective origin (i.e. tornado, downburst and straight-line winds). It is based on previous studies and also on 136 field studies performed by the authors in Spain between 2004 and 2018. The methodology includes the collection of pictures and records of damage to human-made structures and on vegetation during the in situ visit to the affected area, as well as of available automatic weather station data, witness reports and images of the phenomenon, such as funnel cloud pictures, taken by casual observers. To synthesize the gathered data, three final deliverables are proposed: (i) a standardized text report of the analysed event, (ii) a table consisting of detailed geolocated information about each damage point and other relevant data and (iii) a map or a KML (Keyhole Markup Language) file containing the previous information ready for graphical display and further analysis. This methodology has been applied by the authors in the past, sometimes only a few hours after the event occurrence and, on many occasions, when the type of convective phenomenon was uncertain. In those uncertain cases, the information resulting from this methodology contributed effectively to discern the phenomenon type thanks to the damage pattern analysis, particularly if no witness reports were available. The application of methodologies such as the one presented here is necessary in order to build homogeneous and robust databases of severe weather cases and high-impact weather events.

Soybean Sensitivity to Florpyrauxifen-benzyl during Reproductive Growth and the Impact on Subsequent Progeny

2017 ◽  
Vol 32 (2) ◽  
pp. 135-140 ◽  
Author(s):  
M. Ryan Miller ◽  
Jason K. Norsworthy
Keyword(s):  
Plant Height ◽  
Field Studies ◽  
Yield Reduction ◽  
Growth Stages ◽  
Soybean Plant ◽  
Reproductive Growth ◽  
Similar Reduction ◽  
Structural Class ◽  
Soybean Plants ◽  
The Impact

AbstractTo address recent concerns related to auxin herbicide drift onto soybean, a study was developed to understand the susceptibility of the reproductive stage of soybean to a new auxin herbicide compared with dicamba. Florpyrauxifen-benzyl is under development as the second herbicide in a new structural class of synthetic auxins, the arylpicolinates. Field studies were conducted to (1) evaluate and compare reproductive soybean injury and yield following applications of florpyrauxifen-benzyl or dicamba across various concentrations and reproductive growth stages and (2) determine whether low-rate applications of florpyrauxifen-benzyl or dicamba to soybean in reproductive stages would have similar effect on the progeny of the affected plants. Soybean were treated with 0, 1/20, or 1/160, of the 1X rate of florpyrauxifen-benzyl (30 g ai ha−1) or dicamba (560 g ae ha−1) at R1, R2, R3, R4, or R5 growth stage. Soybean plant height and yield was reduced from 1/20X dicamba across all reproductive stages. High drift rates (1/20X) of florpyrauxifen-benzyl also reduced soybean plant height >25% and yield across R1 to R4 stages. Germination, stand, plant height, and yield of the offspring of soybean plants treated with dicamba and florpyrauxifen-benzyl were significantly affected. Dicamba applied at a rate of 1/20X at R4 and R5 resulted in 20% and 35% yield reduction for the offspring, respectively. A similar reduction occurred from florpyrauxifen-benzyl applied at R4 and R5 at the 1/20X rate, resulting in 15% to 24% yield reduction for the offspring, respectively. Based on these findings, it is suggested that growers use caution when applying these herbicides in the vicinity of reproductive soybean.

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