Bacillus amilolyquefaciens ISOLADO E EM MISTURAS COM QUÍMICOS NO CONTROLE DE Scutigerella immaculata: NOVA PRAGA NA SOJA, REGIÃO MAPITOPA

Abstract

Scutigerella immaculata (Symphyla: Scutigerellidae) feeds on plant roots, which has caused problems in soybean production areas in the MAPITOPA region (Maranhão-Piauí-Tocantins-Pará): one of the last agricultural frontiers in Brazil. The objective was to evaluate the efficiency of seed treatment (ST) in soybean (Glycine max L.) for the control of Scutigerella immaculata, with the biological organism Bacillus amyloliquefaciens isolated and in mixtures with other chemical molecules, as well as to record phytotechnical parameters of soybean plants depending on the treatments. Soybean seeds were treated on the day of planting in Açailândia, Maranhão state, Brazil. The procedure for the treatment of seeds took place through plastic bags (3 liters each) and the quantity of seeds per treatment was 100 kg. A DIC experimental design with 9 treatments and 4 replications was adopted, under field conditions. The treatments were T1 (absolute control), T2 (pyrazole), T3 (imidacloprid + neonicotinoid), T4 (neonicotinoid), T5 (Bacillus amyloliquefaciens), T6 (neonicotinoid + pyrazole), T7 (neonicotinoid + lambdacyhalothrin), T8 (neonicotinoid + pyrazole + B. amyloliquefaciens) and T9 (anthraniamide + lambdacyhalothrin + avermectin). Baits with potatoes in the soil or evaluations through direct counting on the roots were the sampling types for the pest in question at 20, 30, 44, 60 and 90 DAP (days after planting). The parameters plant height, seedling emergence, seed germination, root and shoot fresh mass were significantly different. Sampling through evaluations of plant roots to count the pest Scutigerella immaculata represented a greater number of individuals compared to the baits. For sampling through direct counting in the roots, the T7 (neonicotinoid + lambdacyhalothrin) was the one that resulted in the lowest mean number of Scutigerella immaculata. The population increase of the pest was more pronounced from the interval between 60 and 90 DAP, compared to samples taken at 20, 30 or 45 DAP. Further considerations about the positioning of the evaluated biological product, as well as how the TS can help to control this new pest are demonstrated.