Syngenta has recently confirmed the presence of resistance to thiamethoxam in populations of tobacco thrips collected from the Mid South. Thiamethoxam is the active ingredient used for thrips control on cotton seed treated with Cruiser, Cruiser Avicta, and Acceleron N.  It is also the active ingredient used as Cruiser in soybean and corn. This discovery comes as no surprise in Tennessee as thrips control failures on Cruiser treated cotton seed have become more and more common during the past few years.

Unfortunately, tobacco thrips is the primary thrips species that occurs in cotton. We’ve already observed field control failures during the past few years, so it appears evident that there is enough resistance out there to matter. The good news is that thrips, including tobacco thrips, are much less likely to cause economic damage in soybean or corn. Also, only tobacco thrips are known to have developed resistance to thiamethoxam. Early indications are that thiamethoxam resistant populations of tobacco thrips were not resistant to imidacloprid. According to Syngenta, this problem appears to be confined to the Mid South at this time. However, a much larger screening program will be done in 2014.

As seed orders are being made, I felt it was important to get the word out now. The next challenge will be developing a plan for dealing with thiamethoxam resistant tobacco thrips in cotton. This will be a topic of discussion at county meetings and Cotton Focus during the winter months.  My colleague, Dr. Gus Lorenz at the University of Arkansas, has already made some suggestions in the following article:
http://www.arkansas-crops.com/2013/11/08/cruiser-thiamethoxam-seed-treatment-may-be-ineffective-on-tobacco-thrips-in-cotton/.

Thanks to Syngenta for sharing the above information!