Abstract
BACKGROUNDAn evaluation was made of the effects of seven neurotoxic insecticides (esfenvalerate, indoxacarb, clothianidin, thiacloprid, azinphosmethyl, phosmet and imidacloprid), one insect growth regulator (novaluron) and two fungicides (myclobutanin and mancozeb), with water as the control, on the horizontal mobility of plum curculios exposed to dried pesticide residues. Mobility was recorded over a 2 h period using ethological tracking software. Mortality was recorded immediately after horizontal mobility experiments and 24 h later.RESULTSEsfenvalerate had the greatest impact on mobility. Immediately after exposure to this compound, plum curculios moved significantly greater distances and for a significantly longer period of time compared with all other compounds. After 24 h, esfenvalerate also led to high mortality rates (>86.0%). Exposure to azinphosmethyl and phosmet also led to high rates of mortality, although the impact on mobility was less pronounced. Exposure to indoxacarb, thiacloprid, imidacloprid, novaluron, myclobutanin and mancozeb had no impact on mobility and resulted in little to no mortality. Clothianidin affected mobility after a 2 h exposure period, and high mortality (60%) was recorded after 24 h.CONCLUSIONSThe results indicate that, in the context of a treated orchard, plum curculios exposed to dried pesticide residues may be capable of foraging before succumbing to toxicant exposure, while exposure to pesticides such as esfenvalerate may rapidly incapacitate adult plum curculios.
Highlights
The plum curculio, Conotrachelus nenuphar Herbst (Curculionidae), is an extremely destructive key pest of stone and pome fruit in commercial orchards in eastern North America.[1,2,3] As damage from plum curculio can exceed 85% if mitigating management procedures are not taken,[4,5] this insect is considered to be a major obstacle to ecological and sustainable pest management programs in tree fruit orchards
The application of these newer insecticides in tree fruit orchards could lead to differences in results obtained from trap-based monitoring procedures,[11,12] for a perimeter row spray management strategy[13,14] or for the trap tree-based management strategy.[15]
These procedures were developed on the basis of programs using organophosphates such as azinphosmethyl, which has higher acute toxicity and shorter lethal exposure times against adults compared with other newer insecticides,[10] and has demonstrated curative activity against eggs and larvae in fruit such as tart cherry.[16]
Summary
The plum curculio, Conotrachelus nenuphar Herbst (Curculionidae), is an extremely destructive key pest of stone and pome fruit in commercial orchards in eastern North America.[1,2,3] As damage from plum curculio can exceed 85% if mitigating management procedures are not taken,[4,5] this insect is considered to be a major obstacle to ecological and sustainable pest management programs in tree fruit orchards. For the past 40 years, conventional fruit growers have relied essentially on broad-spectrum insecticides, in particular the organophosphates, to provide commercially acceptable pest control. This typically requires three whole-orchard insecticide treatments to manage plum curculio adults in northeastern apple orchards.[6,7] In all cases, growers are forced to apply insecticides to their entire orchard plots, because plum curculio adults move into[8] and disperse throughout commercial plots in response to broadly available stimuli and resources.[3]. Mortality was recorded immediately after horizontal mobility experiments and 24 h later
Sign-in/Register to view highlights & summary Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
