The new IRAC leaflet has been designed in conjunction with CropLife International providing growers with essential information on insect resistance management and the significant benefits for growers. The leaflet is in English at the moment but an editable version will be available shortly so that it can be translated into the local languages and targeted for specific countries and sectors.
The IRAC Methods Team have produced another video in their series of test method videos. This video shows how to carry out Method No.030 evaluating the susceptibility of stinkbugs to insecticides from mode of action groups, 1A (carbamates), 1B (organophosphates), 3A (pyerethroids), and 4A (neonicotinoids). The method has been validated for Euschistus heros and can be used for susceptibility baseline testing and resistance monitoring.
The MoA Classification has been updated by the IRAC MoA Team and the updates approved by the IRAC Executive. The latest version of the Classification Scheme can be downloaded from the IRAC website. The English version of the IRAC Chemical Structures Poster and the small IRAC MoA Booklet have also been update and can be downloaded from the website.
The paper reports on the sensitivity monitoring executed by DuPont and collaborators in Italy, Spain, Greece since 2009 in order to detect possible sensitivity shifts of T. absoluta from baseline sensitivity to the diamide insecticide chlorantraniliprole (MoA group 28). The results of the 2014 bioassays revealed the first cases of T. absoluta resistance to diamide insecticides in South-East Sicily. The potential integrated control strategies are discussed, aiming to prevent further directional selection of resistance alleles via the adoption of stringent IPM strategies inclusive of reasoned IRM/MoA alternation programmes.
- The Insecticide Resistance Management recommendations have been developed by IRAC Brazil & IRAC International and in consultation with leading local experts on Brazilian agriculture and resistance management.
- The recommendations are based on resistance management principles, whilst also considering the need to provide economical pest control. They are intended to provide the basis for developing an effective pest management program that minimizes the risk of insecticide resistance evolution.
- Although the recommendations provides the basis for developing a pest management strategy, local variations in agronomic practice, pest spectrum, crop growth dynamics, pest susceptibility…..etc, mean that adaptation to local conditions is necessary.
Urgent research to understand the nature and extent of insecticide resistance in an increasingly damaging pest of peas and beans is underway at Rothamsted Research. The work is in response to reports of failure to control the pea and bean weevil (Sitona lineatus) with pyrethroid sprays, which are a special chemical class of active ingredients found in many modern insecticides used by growers. For further information see the resistance alert on the Rothamsted Research website
In this issue we focus on mode of action (MoA) and its importance in insecticide resistance management (IRM). We present a review paper on IRM and the IRAC MoA Classification and summarize the changes that have been made to the latest version of the classification scheme.
Download a copy of the newsletter for full details of these articles and find out more about MoA using the links below.
Summary of findings:
- In the majority of countries surveyed, pyrethroid resistant populations of pollen beetle dominate (> 60% are resistant).
- From the countries surveyed, it is only in Switzerland that susceptible populations dominate but sample size was considered too small to be representative of the overall country situation.
- During 2014, only 11% of pollen beetle populations surveyed in Europe could be classified as pyrethroid susceptible.
- After an initial decline in the number of susceptible pollen beetle populations observed in Europe since the IRAC survey began in 2007, only small variations in the percentage of pyrethroid susceptible and resistant beetle populations have been observed since 2010.
- The majority of populations tested across Europe remained susceptible to neonicotinoid insecticides, however the percentage of populations with a lower sensitivity increased to 30% (21% in 2012 & 2013).
- There is currently no evidence to suggest that the lower sensitivity observed in the survey correlates with a reduced performance of neonicotinoid containing insecticide products which are used under field conditions, however resistance management practice should be implemented to avoid further susceptibility decline.
- There was no evidence of changes in organophosphate or indoxacarb susceptibility observed in the European countries surveyed.
The cotton aphid (Aphis gossypii) is a highly polyphagous pest, which has a host range which includes many commercially grown agricultural and horticultural plant species. Insecticide Resistance has been recorded in cotton aphids since the mid-1960‘s, when organophosphate, carbamate and cyclodiene organochlorines were utilised to control this aphid in a wide range of crops. There have been reports of resistance to pyrethroids and a small number of reports of resistance to nicotinic acetylcholine receptor agonist insecticides in cotton (e.g. Australia, China & USA) and cucurbits & vegetables (e.g. Japan & Korea).