Given the lack of effective tools to control cabbage whitefly , the Ministry of Agriculture, Fisheries and Food (Spain) has granted exceptional authorization for the marketing and use of plant protection products formulated with 12% [SC] w/v sulfoxaflor for the control of cabbage whitefly (Aleyrodes proletella) in broccoli crops. The decision is based upon the uncontrolled increase in populations of this insect due to rising temperatures, as well as the direct and indirect damage it causes to brassica crops.
The whitefly, whose life cycle develops mainly on the underside of leaves, hinders the effectiveness of non-systemic contact insecticides. The damage it causes includes weakening plants due to its sap-sucking action and the appearance of fungi associated with the honeydew it secretes.
The authorization, initially granted for Castilla-La Mancha, has subsequently been extended to the Region of Murcia, the Valencian Community, Navarre, and La Rioja; in all cases, the authorized period runs from October 30 to December 31. Use of the product is limited to a single application, at BBCH stage 20-49, with a dose of 0.2 L/ha and a spray volume between 200 and 1,000 L/ha. The pre-harvest interval is seven days.
In the resolution, the Ministry establishes specific risk mitigation measures for both operators and the environment. These include the wearing of gloves and protective clothing during mixing and application, avoiding contact with wet foliage, and maintaining five-meter buffer zones to protect aquatic organisms and non-target arthropods. Also, the resolution emphasizes the product's hazard to bees and prohibits the use of sulfoxaflor during flowering or in the presence of active pollinators.
The cabbage whitefly is considered one of the main pests attacking brassica crops. This year, a study by the Valencian Institute of Agricultural Research (IVIA) and the Canary Islands Institute of Agricultural Research (ICIA) was published in Phytoma, aiming to lay the groundwork for a future integrated pest management program for A. proletella. The study, conducted on two plots located in the province of Castellón, revealed that biological control has great potential for development and that current problems with the whitefly result from a combination of factors: the increase in growing seasons throughout the year, which prevents interruption of the pest's life cycle; the development of agricultural landscapes with cabbage monoculture, where the whitefly finds unlimited resources; the pressure of phytosanitary treatments across the growing area on the pest's main natural enemy, Encarsia tricolor; and the lack of refuge areas and alternative food sources for these parasitoids in the crop and in adjacent areas.
The authors of this work propose to develop new management strategies for A. proletella that minimize the use of insecticides and takes advantage of the potential benefits of implementing biological control.
