Integrated Effect of Plastic Mulches and Biorational Insecticides in Managing Tomato Chlorotic Spot Virus (TCSV) and Its Vector Thrips in Tomatoes

SIMPLE SUMMARY: Thrips transmitted tomato chlorotic spot virus (TCSV) is one of the limiting factors of tomato production in South Florida. After invading in 2012, growers are mostly dependent on conventional and broad-spectrum insecticides to face this challenge. Insecticide alone is inadequate to manage this pest-borne disease. A combined effect of cultural and chemical control strategy can be a potential management approach for this pest without imposing any environmental stress. The present study was conducted to determine the effect of four different plastic mulches and four biorational insecticides on the abundance of thrips population, marketable yield, and presence of TCSV-infected tomatoes. Reflective plastic mulches, especially silver on black (S/B) and Entrust(®)SC, among the biorational insecticides used, were the most effective in managing the thrips population while increasing the marketable yield and reducing the TCSV-infected tomatoes. ABSTRACT: In the USA, tomato chlorotic spot virus (TCSV) was first identified in Miami-Dade County of Florida in 2012. This viral disease is transmitted by thrips (Thysanoptera: Thripidae) of different species, imposing a serious threat to the entire tomato production in the state. Both cultural and chemical control techniques could be essential tools to combat this vector-borne disease. In the present two-year-long study, we determined the effect of different types of plastic mulches and biorational insecticides on managing thrips and TCSV. Results from the leaf and flower samples showed a significantly lower adult thrips population in Entrust(®)SC treated tomatoes than in other treated and untreated tomatoes in 2018. Silver on black and silver on white reflective plastic mulches significantly reduced the adult thrips population in 2018. In both study years, marketable yield was significantly higher in tomatoes treated with Entrust(®)SC and reflective plastic mulches than in other treatments. The incidence of TCSV was significantly reduced in tomatoes treated with Entrust(®)SC and reflective plastic mulches than the untreated control in 2018. Marketable yield was negatively correlated with the thrips population, as observed from the Pearson correlation coefficient analysis. This research describes a potentially viable management program for thrips and thrips-transmitted TCSV.