Thrips Species Present in Mississippi Cotton

By now everyone is fully aware that we have been and still are experiencing extremely high levels of thrips in cotton.  To date, many fields have been treated with foliar insecticides and several have required repeat applications due to extremely high numbers and frequent re-infestations.  On May 19^th we made trips across the north and south delta collecting cotton samples from random fields to get an idea of the species composition present.  Ordinarily, tobacco thrips are the most common species we deal with in seedling cotton; however, on occasion western flower thrips infest seedling cotton in MS.  It is important to note that western flower thrips are extremely difficult to control with the current products we have available.  Typically it takes high rates of acephate 0.5 -1.0 lb and results can still be marginal.  From the survey, we can see that in several fields we already have reproduction occurring on cotyledon cotton.  There are various degrees of western flower thrips mixed in these populations, but they are present in most fields.  In most cases if you see winged adult dark color or black thrips in MS cotton chances are they are tobacco thrips which have been easy to control.  If you see winged adult larger yellow/orange thrips it is likely western flower thrips.  There are several other yellow or orange color adult thrips that are not western flower thrips but based on samples identified by Dr. Don Cook, this year they are mainly western flower thrips.  After you make one foliar application it is highly likely that you will select for western flower thrips and they may be the predominant thrips species present in your field.  If you have made one application already and are left with yellow/orange winged adult thrips I would consider trying to live with them rather than trying to control western flower thrips in seedling cotton and flaring spider mites or aphids with high rates of acephate unless populations are just too high to try and outrun.  As always call with any questions.