TOBACCO TRANSPLANT TREATMENTS CRITICAL IN CONTROLLING TSWV
Tobacco growers have seen a sharp decline in tomato spotted wilt virus (TSWV) over the past few years and have wondered if they could get by without the greenhouse treatments of Actigard and imidacloprid. The answer to that question is a resounding NO! Dr. Paul Bertrand, retired University of Georgia Extension pathologist, has set out numerous tobacco plots in 2012 comparing untreated transplants with Actigard and imidacloprid transplants (and a few with just imidacloprid). In one location in Coffee County, we had some wind damage and lost about 50% of the stand on the Actigard+imidacloprid transplants compared to almost a 100% stand on the untreated (see photo below). The grower said he sure wished we could quit using Actigard since he had to replant that field. We have long seen that the greenhouse applications, especially Actiguard, have an adverse effect on the transplants’ liveability in adverse conditions. Growers would like to avoid these applications but recent TSWV ratings from Dr. Bertrand (below) show how critical Actigard and imidacloprid still are in reducing TSWV. Dr. Bertrand’s recent ratings had almost four times the TSWV in the untreated plots (13.45%) compared to the Actigard+imidacloprid plots (3.6%).