Cases of Insecticide resistance associated with the cotton aphid (Aphis gossypii) have been reported since the mid-1960‘s. Resistance to organophosphate, carbamate, cyclodiene organochlorine and pyrethroid insecticides are considered as globally widespread.
More recently there have been substantive reports of resistance to the nicotinic acetylcholine receptor competitive modulators (IRAC group 4). This group of chemistries has provided effective control of the cotton aphid for many years, but now reports of resistance are increasing.
This module is designed to introduce the basic concepts behind the development and management of insecticide resistance in agricultural and horticultural crops. The presentation is targeted to those that may be being exposed to the concept of insecticide resistance for the first time or simply wishing to refresh their knowledge. More detailed information on the factors which influence resistance development and its management will be provided in future modules produced by IRAC International.
In South Africa, it will be critically important to have a harmonised approach to IRM for FAW across the industry and across technologies. This approach should combine a clear and simple structured refuge policy which does not confuse growers between the requirements for FAW and maize stalk borers in South Africa, and which enables a high grower compliance. There are several commercialised Bt-products in South Africa which are very similar. This approach is in the best interests of the seed industry, growers and South African consumers. The new guidelines have now been published on the IRAC website.
Conclusions from the program:
Growers in Canada can get ahead of insecticide resistance with the help of new resources on ManageResistanceNow.ca. The website, which compiles the most up-to-date knowledge on pesticide resistance in Canadian agriculture, now includes best practices for managing insecticide resistance.
“More than one-third of Canadian growers are concerned about the rise of insecticide resistance in the next few years,” says Pierre Petelle, president and CEO of CropLife Canada. “It’s critical to adopt best practices to manage resistance, both to protect crop yield today and to ensure sustainable production for the future.”
Insecticide resistance is not as common as herbicide resistance in weeds but with that comes a unique set of challenges. For example, because many Canadian growers have yet to see evidence of insecticide resistance in their fields, they may not appreciate the need to manage for the problem now. The new resources highlight the need for proactivity and encourage growers to use a combination of physical, cultural, biological and chemical control measures to keep ahead of the issue.
The IRAC Mode of Action Working Group have developed a set of 74 slides as a MoA tutorial outlining the major mechanisms of insecticide resistance and, explaining with graphics, MoA by the targeted physiology affected using the broad categories of: Nerve and Muscle, Growth and Development, Respiration, Midgut and Unknown or Non-specific target sites or functions. This is now available in Japanese as well as English
IRAC España ha emitido una alerta sobre resistencias de Ceratitis capitata en cítricos. Desde hace varios años están descritos casos de resistencias de Ceratitis capitata a piretroides (MdA nº 3A), básicos en la estrategia de control de la mosca de la fruta en cítricos, tanto en trampas de captura masiva y/o técnicas de “atracción y muerte” como en cebo durante el periodo de cambio de color de la fruta. La colocación de trampas a inicio de campaña implica que la plaga está expuesta varios meses a un mismo MdA, siendo necesario una alternancia en el MdA de los tratamientos posteriores en maduración.
IRAC España ha emitido una alerta sobre riesgo de resistencias de Bactrocera oleae en olivo. La mosca del olivo (Bactrocera oleae) es junto a Prays oleae la plaga más importante del cultivo. Existen un limitado número de productos autorizados en el control de mosca del olivo, y gran parte de la superficie está en sistemas de Producción Integrada, limitando aún más las herramientas. Tanto en organofosforados como piretroides, principales herramientas de control en la actualidad, ya se han identificado mecanismos de resistencia en poblaciones de campo de mosca del olivo del área Mediterránea.
The IRAC Nematode Working Group is the most recently established IRAC team. The initial objectives of the team were to investigate the resistance risk of nematicides and to develop a mode of action classification scheme similar to that available for insecticides and acaricides.
Both these objectives have now been completed with the publication of the Nematicide Resistance Risk Statement at the end of 2018 and more recently the release of the Nematicide MoA Classification and corresponding MoA poster in September 2019
CropLife formally confirmed the UPL membership of IRAC International on the 23rd August 2019. With the mergers and acquisitions of various crop protection companies, along with the joining of UPL, this brings the number of IRAC International company members to 11. Good representation across the industry enables IRAC to continue providing a global coordinated response to insect resistance management strategies.