Mixtures between Beauveria bassiana and potassium silicate to manage thrips in tomato plants for industrial processing

Resumo

Thysanoptera species can transmit irreversible virus to Solanaceae family vegetables, including tomato plants for industrial processing, causing the disease known as Tomato Spotted Wilt Virus (TSWV). Thrips resistance to insecticides indicate the urgent need of techniques adequate to Integrate Pest Management practices. The objective was to evaluate the control efficiency (CE%) to Frankliniella schultzei (Trybom) (Thysanoptera: Thripidae) with the fungus Beauveria bassiana (Bb), the resistance inducer potassium silicate (KSil) and the chemical insecticide (Profenofos + Cypermethrin) (PC) isolated, or in binary mixtures, in Goiás state, Brazil. The treatments were foliar spraying of tomato plants with Bb (T1), KSil (T2) and PC (T3) isolated or in mixtures of Bb + KSil (T4), PC + KSil (T5) and Bb + PC (T6). Thrips were sampled with white plastic trays at 0, 1, 7, 14 and 21 days after the product application (daa). The CE% of each product (isolated or in mixtures) differed at all time intervals. The Bb + KSil treatment had highest CE% from 24 hours of application, until the end of the experiment, ranging from 95.00 % (1 daa) to 41.50 % (21 daa). But CE% decreased in all treatments with a quadratic behavior, throughout time. PC insecticide, isolated, showed a decreased CE% through a linear regression. Grouping analyzes indicated the Bb + KSil effect was more heterogeneous than the order evaluated treatments. Synergism between Bb and KSil, in mixture, indicate its potential for Integrated Pest Management programs of F. schultzei in tomato for industrial processing plants.