Rainfall influences performance of insecticides on the codling moth (Lepidoptera: Tortricidae) in apples

2016 ◽  
Vol 149 (1) ◽  
pp. 118-128 ◽  
Author(s):  
John C. Wise ◽  
Daniel Hulbert ◽  
Christine Vandervoort
Keyword(s):  
Pest Management ◽  
Untreated Control ◽  
Codling Moth ◽  
Field Studies ◽  
Simulated Rainfall ◽  
Negative Effects ◽  
Rainfall Events ◽  
Apple Leaves ◽  
Compound Plant ◽  
Rainfall Level

AbstractSemi-field studies were used to evaluate the effects of rainfall and field ageing on the performance of insecticides from six different chemical classes used to control the codling moth (Lepidoptera: Tortricidae). All insecticides were significantly more toxic to codling moth larvae than the untreated control, although seven-day field ageing reduced control for several compounds. Simulated rainfall events of 2.54 and 12.7 mm did not have negative effects on the performance of the insecticides. Simulated rainfall events of 50.8 mm of rainfall resulted in significant reductions of efficacy for thiacloprid and spinetoram. Residue profiles of apple leaves and fruit provided evidence for wash-off ranging from 13% to 93%, with patterns varying by compound, plant substrate, and rainfall level. This study will help apple growers make informed decisions on when reapplications of insecticides are needed in the field with the aim of improving integrated pest management.

Foliar Penetration and Phytotoxicity of Paraquat as Influenced by Peanut Cultivar1

1991 ◽  
Vol 18 (2) ◽  
pp. 67-71 ◽  
Author(s):  
G. Wehtje ◽  
J. W. Wilcut ◽  
J. A. McGuire ◽  
T. V. Hicks
Keyword(s):  
Arachis Hypogaea ◽  
Untreated Control ◽  
Field Studies ◽  
Yield Potential ◽  
Laboratory Studies ◽  
Foliar Absorption ◽  
Arachis Hypogaea L ◽  
Herbicide Treatments ◽  
Peanut Cultivars

Abstract Field studies were conducted over a three year period to examine the sensitivity of four peanut (Arachis hypogaea L.) cultivars (Florunner, Sunrunner, Southern runner, and NC 7) to foliar applications of paraquat (1, 1′-dimethyl-4, 4′-bipyridinium ion). Treatments included an untreated control and four herbicide treatments: paraquat applied alone at 0.14 and 0.28 kg/ha, or tank mixed with alachlor [2-chloro-N-(2, 6-diethylphenyl)-N-(methoxymethyl)acetamide] at 4.40 kg/ha. Weeds were hand-removed so that only herbicidal treatments were variables. Paraquat phytotoxicity did not differ between cultivars. No cultivar evaluated was abnormally sensitive nor tolerant to any paraquat-containing treatment. Laboratory studies utilizing radio labelled paraquat revealed that foliar absorption and translocation of paraquat did not vary between peanut cultivars. Yield differences were attributed to differences in yield potential between cultivars.

EFFECTS OF RESIDUES OF CHITIN-SYNTHESIS INHIBITORS ON EGG HATCH AND SUBSEQUENT LARVAL ENTRY OF THE CODLING MOTH, CYDIA POMONELLA (LEPIDOPTERA: OLETHREUTIDAE)

1984 ◽  
Vol 116 (8) ◽  
pp. 1057-1062 ◽  
Author(s):  
H. R. Moffitt ◽  
K. D. Mantey ◽  
G. Tamaki
Keyword(s):  
Cydia Pomonella ◽  
Residual Activity ◽  
Codling Moth ◽  
Field Studies ◽  
Ring Stage ◽  
Chitin Synthesis ◽  
Egg Hatch ◽  
Chitin Synthesis Inhibitors ◽  
Stage Of Development ◽  
Previously Treated

AbstractIn laboratory and field studies with the codling moth, Cydia pomonella (L.), TH 6043 and TH 6044, experimental benzoylphenyl urea chitin-synthesis inhibitors, were as effective as diflubenzuron in reducing egg hatch and subsequent larval entry when eggs were deposited on previously treated fruits or foliage. All three compounds exhibited extended residual activity, with significant reductions in egg hatch occurring over a 19-week period. TH 6045 exhibited little activity against codling moth. All compounds tested were relatively ineffective in reducing egg hatch or subsequent larval entry when they were applied topically to deposited eggs, except for the red ring stage of development which was slightly affected.

Additive negative effects of Philornis nest parasitism on small and declining Neotropical bird populations

2018 ◽  
Vol 29 (03) ◽  
pp. 339-360 ◽  
Author(s):  
MARIANA BULGARELLA ◽  
MARTÍN A. QUIROGA ◽  
GEORGE E. HEIMPEL
Keyword(s):  
Bird Species ◽  
Field Studies ◽  
Habitat Destruction ◽  
Biological Information ◽  
Mortality Factor ◽  
Healthy Population ◽  
Small Populations ◽  
Negative Effects ◽  
Nest Parasitism ◽  
Bird Populations

SummaryThe declining-population paradigm holds that small populations are particularly vulnerable to anthropogenic influences such as habitat destruction, pollution and species introductions. While the effects of particular stressors, such as parasitism, may be unimportant in a large, healthy population, they can be serious and even devastating in situations characterised by a restricted geographic range, or by fragmented or reduced population sizes. We apply this idea to nest parasitism of threatened Neotropical bird species that exist in small populations, focusing on dipteran nest parasites in the genusPhilornis. We review the literature onPhilornisparasitism exerting negative pressure on bird populations that have become small and isolated due to human actions and present a new case ofPhilornisparasitism of a threatened hummingbird species. Our aim is to raise awareness about the exacerbating effect that nest parasites can have on small and declining bird populations; especially when biological information is scarce. The five reviewed cases involve two species of Darwin’s Finches in the Galápagos Islands attacked by the invasiveP. downsi, two species of hawks on islands in the Caribbean attacked by the nativeP. piciandP. obscura, and the Yellow CardinalGubernatrix cristatain southern South America attacked by an unknownPhilornisspecies. We also present new documentation of parasitism of a threatened hummingbird species in mainland Ecuador by an unidentifiedPhilornisspecies. We recommend more field studies to determine the presence of nest parasites in bird populations worldwide to improve understanding how nest parasites affect bird fitness and population viability and to allow time to act in advance if needed. Parasitism byPhilornismay represent a severe mortality factor in most already threatened bird species, putting them at greater risk of extinction. Therefore, parasitism management should be included in all threatened species recovery plans.

Uncovering the Mitigating Psychological Response to Monitoring Technologies: Police Body Cameras Not Only Constrain but Also Depolarize

2021 ◽  
Author(s):  
Shefali V. Patil ◽  
Ethan S. Bernstein
Keyword(s):  
Law Enforcement ◽  
Strong Support ◽  
Field Studies ◽  
Negative Effects ◽  
Technological Advances ◽  
Ideological Divergence ◽  
Monitoring Technologies ◽  
Ideological Tensions ◽  
Shed Light ◽  
Psychological Benefit

Despite organizational psychologists’ long-standing caution against monitoring (citing its reduction in employee autonomy and thus effectiveness), many organizations continue to use it, often with no detriment to performance and with strong support, not protest, from employees. We argue that a critical step to resolving this anomaly is revisiting researchers’ fundamental assumptions about access to gathered data. Whereas previous research assumes that access resides nearly exclusively with supervisors and other evaluators, technological advances have enabled employee access. We hypothesize that with employee access, the psychological effects of monitoring may be far more complex than previously acknowledged. Whereas multiparty access may still decrease employee autonomy, it may also trigger an important psychological benefit: alleviating employees’ perceptions of polarization—the increasing social and ideological divergence between themselves and their evaluators. Access gives employees unprecedented opportunities to use the “objective” footage to show others their perspective, address evaluators’ erroneous assumptions and stereotypes, and otherwise defuse ideological tensions. Lower perceived polarization, in turn, attenuates the negative effects that low autonomy would otherwise have on employee effectiveness. We find support for these hypotheses across three field studies conducted in the law enforcement context, which has been a trailblazer in using technological advances to grant broad access to multiple parties, including employees. Overall, our studies shed light on the conflicting (and ultimately more innocuous) impact of monitoring and encourage scholars to break from prior approaches to account for its increasing egalitarianism.

Response of Johnsongrass (Sorghum halepense) and Imidazolinone-Resistant Corn (Zea mays) to AC 263,222

1999 ◽  
Vol 13 (3) ◽  
pp. 484-488 ◽  
Author(s):  
John W. Wilcut ◽  
John S. Richburg ◽  
F. Robert Walls
Keyword(s):  
Zea Mays ◽  
Weed Control ◽  
Untreated Control ◽  
Field Studies ◽  
Sorghum Halepense ◽  
Corn Yield ◽  
Redroot Pigweed ◽  
Herbicide Treatments ◽  
Ac 263,222 ◽  
Large Crabgrass

Field studies were conducted in 1992 and 1993 to evaluate AC 263,222 applied postemergence (POST) alone and as a mixture with atrazine or bentazon for weed control in imidazolinone-resistant corn. Nicosulfuron alone and nicosulfuron plus atrazine were also evaluated. Herbicide treatments were applied following surface-banded applications of two insecticides, carbofuran or terbufos at planting. Crop sensitivity to POST herbicides, corn yield, and weed control was not affected by insecticide treatments. AC 263,222 at 36 and 72 g ai/ha controlled rhizomatous johnsongrass 88 and 99%, respectively, which was equivalent to nicosulfuron applied alone or with atrazine. AC 263,222 at 72 g/ha controlled large crabgrass 99% and redroot pigweed 100%, and this level of control exceeded that obtained with nicosulfuron alone. AC 263,222 at 72 g/ha controlled sicklepod and morningglory species 99 and 98%, respectively. Nicosulfuron alone or with atrazine controlled these two species less than AC 263,222 at 72 g/ha. Addition of bentazon or atrazine to AC 263,222 did not improve control of any species compared with the higher rate of AC 263,222 at 72 g/ha applied alone. Corn yield increased over the untreated control when POST herbicide(s) were applied, but there were no differences in yield among herbicide treatments.

scholarly journals Fungicides for Control of Downy Mildew on Pickling Cucumber in Michigan

2019 ◽  
Vol 20 (3) ◽  
pp. 165-169 ◽  
Author(s):  
Katelyn E. Goldenhar ◽  
Mary K. Hausbeck
Keyword(s):  
Downy Mildew ◽  
Untreated Control ◽  
Field Studies ◽  
Pseudoperonospora Cubensis ◽  
Relative Area ◽  
Disease Progress Curve ◽  
Cucurbit Downy Mildew ◽  
Disease Progress ◽  
Pickling Cucumber ◽  
Progress Curve

Michigan growers rely on fungicides to limit cucurbit downy mildew (CDM), incited by Pseudoperonospora cubensis; resistance of the pathogen to fungicides is a concern. We evaluated fungicides against CDM in Michigan field studies from 2015 to 2017. According to the relative area under the disease progress curve (rAUDPC), in 2015, mandipropamid, propamocarb, fluxapyroxad/pyraclostrobin, copper octanoate, and dimethomorph resulted in disease levels similar to the control. These treatments, along with cymoxanil, were similar to the control in 2016. Fungicides that were ineffective during 2015 and 2016 did not limit CDM in 2017. Famoxadone/cymoxanil and fluopicolide did not limit CDM in 2017. Each year, the following treatments were similar for disease based on rAUDPC data: oxathiapiprolin applied alone or premixed with chlorothalonil or mandipropamid, ametoctradin/dimethomorph, fluazinam, mancozeb/zoxamide, cyazofamid, and ethaboxam. An exception occurred in 2017, when ethaboxam was less effective than fluazinam, oxathiapiprolin/chlorothalonil, and oxathiapiprolin/mandipropamid. Mancozeb and chlorothalonil treatments were similar in 2015 and 2017, according to rAUDPC data. In 2017, yields were increased for oxathiapiprolin/chlorothalonil, oxathiapiprolin/mandipropamid, mancozeb, ametoctradin/dimethomorph, mancozeb/zoxamide, ethaboxam, cyazofamid, chlorothalonil, and fluazinam compared with the untreated control.

Evaluation of the push-pull tactic against the mountain pine beetle using verbenone and non-host volatiles in combination with pheromone-baited trees

2006 ◽  
Vol 82 (4) ◽  
pp. 579-590 ◽  
Author(s):  
John H Borden ◽  
Anna L Birmingham ◽  
Jennifer S Burleigh
Keyword(s):  
Pest Management ◽  
Untreated Control ◽  
Pinus Contorta ◽  
Mountain Pine Beetle ◽  
Dendroctonus Ponderosae ◽  
Wide Band ◽  
Mountain Pine ◽  
Pine Beetle ◽  
The Mean ◽  
Lodgepole Pines

Experiments were conducted near Williams Lake and Quesnel, BC in 2003 to evaluate the effectiveness of the anti-aggregation pheromone verbenone and a three-component non-host volatile (NHV) blend (E-2- and Z-3-hexen-1-ol and benzyl alcohol) in deterring attack of lodgepole pines, Pinus contorta var. latifolia Engelmann, by the mountain pine beetle, Dendroctonus ponderosae Hopkins. In 0.16-ha square plots, with a pheromone-baited tree in the centre and 16 release points at 10-m centres, either verbenone (in a polyurethane gel inside plastic membrane pouches, released at ca. 100 mg/day) or the NHVs (released from separate bubble caps at ca. 1.2 mg/day) deterred attack, but efficacy was not increased by combining them. When deployed from 25 release points at 10-m centres in 0.25-ha square plots, verbenone plus NHVs were effective in deterring attack in some (but not all) cases, when compared to attack in a 25-m wide band around the treated zone. In a test of the push-pull tactic, verbenone plus the NHV blend were tested in a 10-replicate experiment with 100, 44.4 or 25 release points/ha at 10-, 15- or 20-m centres, respectively, in a 1-ha square central zone surrounded by a 3-ha, 50-m-wide band containing 12 pheromone-baited lodgepole pines 50 m apart. Other treatments were pheromonebaited trees alone, and an untreated control. In the three push-pull treatments (but not the bait only or control treatments), 28 of 30 replicates had significantly more mass-attacked trees in the pheromone-baited outer 3 ha than in the inner ha treated with verbenone plus NHVs. The percentage of available trees ≥ 17.5 cm diameter at breast height (dbh) that were mass-attacked was < 10% in 5, 4 and 3 of 10 replicates when verbenone plus NHVs were deployed at 10-, 15- and 20-m centres, respectively, and was < 10% in two each of the bait only and control replicates. The mean ratios of newly-attacked green trees in 2003 to red trees killed in 2002 were significantly lower in the inner ha of the 10-m and 15-m centre treatments (2.6 and 2.7, respectively) than 5.9 in the untreated control. Also the pooled percentages of attacked trees that were not mass-attacked were significantly higher in the inner ha of the treatments with centres at 15 m (24.7%) and 10 m (17.6%) than in the other three treatments (all between 12% and 13%). Despite the apparent efficacy in 10-m and 15-m centre treatments, some replicates failed spectacularly. Failure was not significantly related to the incidence of red trees, but was negatively related to density/ha of available trees and positively related to mean dbh. We recommend operational implementation of the push-pull tactic at 10-m or 15-m centres when the density of available lodgepole pines is > 400/ha, the mean dbh is ≤ 25 cm, current attack is ≤ 15%, and the tactic is part of an integrated pest management program that includes sanitation harvesting. Using verbenone alone at 15-m centres would cost $380/ha (CAD), excluding labour. Key words: mountain pine beetle, Dendroctonus ponderosae, lodgepole pine, Pinus contorta var. latifolia, pheromones, semiochemicals, pest management

scholarly journals A New Phytosanitary Method to Reduce the Ascospore Potential of Venturia inaequalis

Plant Disease ◽  
2017 ◽  
Vol 101 (3) ◽  
pp. 414-420 ◽  
Author(s):  
Franziska M. Porsche ◽  
Barbara Pfeiffer ◽  
Andreas Kollar
Keyword(s):  
Leaf Litter ◽  
Yeast Extract ◽  
Untreated Control ◽  
Venturia Inaequalis ◽  
Apple Scab ◽  
Nutrient Media ◽  
Apple Leaves ◽  
Litter Decay ◽  
Ascospore Discharge ◽  
Infection Pressure

Ascospores of Venturia inaequalis, released from pseudothecia in overwintered, infected apple leaves, serve as the primary inoculum for apple scab. In this study, we tested a new sanitation strategy to reduce ascospore inoculum under orchard conditions over three overwintering periods. After leaf fall, nutrient media containing different concentrations of degraded casein or a yeast extract from Saccharomyces cerivisiae were applied to leaf litter infected with apple scab. The application of 30 and 60% yeast extract showed the greatest efficacy, and significantly reduced ascospore discharge by 99% (P < 0.01) in 2013 and 2014. The efficacy of the treatments did not differ from treatment with 5% urea (P > 0.05). Leaf litter decay was accelerated in the plots treated with yeast extract compared with untreated control plots. Moreover, apple leaves treated with yeast extract had completely decayed due to earthworm activity before ascospore maturity. In comparison, up to 26% of the leaves in untreated control plots had not decayed. These results suggest that the treatment of leaf litter with yeast extract can almost completely eliminate apple scab inoculum in the course of the whole primary season. These sanitation practices may be beneficial for both organic and conventional cultivation. The reduced infection pressure may allow growers the usage of fungicides with lower efficacy or to reduce the number of applications needed to manage apple scab in spring.

‘Olathe’ Pinto Bean (Phaseolus vulgaris) Response to Postemergence Imazethapyr and Bentazon

Weed Science ◽  
1995 ◽  
Vol 43 (2) ◽  
pp. 276-282 ◽  
Author(s):  
Troy A. Bauer ◽  
Karen A. Renner ◽  
Donald Penner
Keyword(s):  
Untreated Control ◽  
Quantitative Measure ◽  
Field Studies ◽  
Dry Bean ◽  
Physiological Maturity ◽  
Pinto Bean ◽  
Treated Leaf ◽  
Dry Edible Bean ◽  
Seed Yields ◽  
Petroleum Oil

Dry bean producers have limited postemergence broadleaf weed control options. The purpose of this research was to determine whether bentazon increased dry edible bean tolerance to postemergence imazethapyr applications. Imazethapyr and bentazon were applied with a petroleum oil adjuvant to ‘Olathe’ pinto bean in the field and greenhouse. Imazethapyr injured pinto bean 7 DAT in the field and greenhouse. Chlorophyllacontent, a quantitative measure of bean chlorosis, decreased compared to the untreated control following imazethapyr application. When 840 g ha−1of bentazon was tank-mixed with 53 g ha−1of imazethapyr, bean injury decreased and chlorophyllaincreased compared to imazethapyr alone. Fifty three g ha−1of imazethapyr delayed physiological maturity by 8 and 15 d compared to the untreated control in 1991 and 1992, respectively. Pinto bean seed yields were not reduced compared to the untreated control. When 840 g ha−1of bentazon was tank-mixed with 53 g ha−1of imazethapyr, maturity was not delayed.14C-Imazethapyr absorption decreased by more than 40% and translocation of14C from the treated leaf decreased by more than 50% when14C-imazethapyr was tank-mixed with bentazon compared to14C-imazethapyr alone. The addition of 20 mM Na-acetate inhibited absorption of14C-imazethapyr, but did not inhibit translocation of14C. The decreased absorption and translocation of imazethapyr when tank-mixed with bentazon likely accounts for the safening effect observed in greenhouse and field studies.

Foliar and Root Absorption of Atrazine Applied Postemergence to Giant Foxtail

Weed Science ◽  
1969 ◽  
Vol 17 (2) ◽  
pp. 251-256 ◽  
Author(s):  
Lafayette Thompson ◽  
F. W. Slife
Keyword(s):  
Field Experiments ◽  
Soil Surface ◽  
Dry Weight ◽  
Field Studies ◽  
Simulated Rainfall ◽  
Root Absorption ◽  
Giant Foxtail ◽  
Setaria Faberii ◽  
Chamber Studies ◽  
Growth Chamber Studies

In growth chamber studies, high relative humidity and rewetting crystalline spray deposits of 2-chloro-4-ethylamino-6-isopropylamino-s-triazine (atrazine) increased absorption by and phytotoxicity to giant foxtail (Setaria faberii Herrm.), but phytotoxicity was restricted to expanded (unrolled) leaves unless some atrazine was absorbed by the roots. Though phytotoxicity was increased by simulated rainfall when root absorption was prevented, an appreciable number of the plants were killed only when atrazine residues were washed into the soil. In field studies, atrazine applied to a wet soil surface was as effective as the same rate of atrazine foliarly applied. In other field experiments, atrazine applied to giant foxtail on a wet soil and followed by simulated rainfall reduced stand and dry weight, but on a dry soil and not followed by simulated rainfall, atrazine reduced dry weight less and did not reduce stand. These results are due to root absorption of atrazine from wet soil. Spray additives increased phytotoxicity.

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