Effect of storage on the physiological quality of soybean seeds treated with insecticides

Abstract

The use of insecticides for seed treatment is one of the most effective of modern pest control concepts. Therefore, the influence of these products on the physiological quality of treated seeds should be known. This study aimed to evaluate the physiological quality of insecticide-treated soybean seeds stored for four different periods (0, 15, 30 and 45 days after treatment). The experimental design was completely randomized in a 4 x 7 factorial design with four replications. Seeds of M-SOY 6101 were treated with thiamethoxam (Cruiser 700 WS) at a dosage of 250 mL commercial product (c.p.)/ 100 kg of seeds; fipronil (Standak) at a dosageof 150 mL/100 kg of seeds, imidacloprid (Gaucho FS) at a dosage of 150 mL/100 kg of seeds; [imidacloprid + thiodicarb] (Cropstar FS) at a dosage of 0.3 L. ha-1; carbofuran (Furadan 350 TS) at a dosage of 1.5 L/100 kg of seeds, acephate (Orthene 750 BR) at a dosage of 1 kg/100 kg of seeds and an untreated control. The variables analyzed were: germination, speed of emergence, root and seedling length and percentage of normal seedlings after accelerated ageing. The application of the insecticides acephate and carbofuran is harmful to the seed quality of the soybean cultivar M-SOY 6101, for a storage period of 45 days. The reduction in seed quality caused by insecticides intensifies with the prolonged storage of treated seed and, therefore, it is recommended that the insecticide seed treatment be done close to sowing.