Original scientific paper
Effect of presowing treatment of seeds with insecticides on parameters related to nodulation and nitrate reduction in soybean [Glycine max (L.) Merr.]
2014, 15 (2) p. 23-32
Effect of presowing treatment of seeds with insecticides on parameters related to nodulation and nitrate reduction in soybean was studied in pot trial at the Institute of Forage Crops, Pleven, Bulgaria (2003-2004). It was found that insecticides Gaucho 600 FS (imidacloprid), Carbodan 35 ST (carbofuran) applied for presowing treatment of seeds at the doses of 1, 2 and 3 L/100 kg seeds, and Promet 400 CS (furathiocarb) (standard) at the dose of 3 L/100 kg seeds, had no suppressive effect on the root length, dry root mass and specific nodulating ability of plants. When used Gaucho 600 FS at the dose of 1 L/100 kg seeds, root mass was most developed, the largest number of nodules was formed, and specific nodulating ability was highest. The common tendency for decrease of nitrate reductase activity in leaves and significant increase in stems was found. Nitrate reductase activity increased in leaves, stems and roots in treatment with Carbodan 35 ST applied at the dose of 3 L/100 kg seeds. Chlorophylls а+b/carotenoids ratio exceeded this of the control only in treatment with Gaucho 600 FS at the dose of 1 L/100 kg seeds. However the analysis of the plant biomass did not include the amount of possible undegraded traces after using the insecticides tested.