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Industrial seed treatment of soybean [Glycine max (L.) Merr.] has increased over the last years. New technologies have been developed to allow the inoculation procedure, which is traditionally done at the day of sowing, to be performed with the industrial treatment days or even weeks before sowing. Since little is known about the compatibility of agrochemicals and pre-inoculation, the objective of this study was to determine whether the storage period and the combination of fungicides and insecticides could negatively affect the physiological quality and yield of soybean seeds that were pre-inoculated. Soybean seeds received fourteen seed treatments that consisted of different fungicides and insecticides and were pre-inoculated with Bradyrhizobium elkanii. The seeds were treated and stored for 51 days until it was sown in the field. Every 17 days the physiological quality of the seed was assessed. The results shown that pre-inoculation did not affect the physiological quality of seeds. However, some combinations of agrochemicals, as well as storage period reduced seed vigor and seed germination, while increased abnormal seedlings. The findings of this study indicated that some combinations of fungicides and insecticides can have adverse effect on the physiological quality of seed that is stored for up to 51 days before sowing, but none of them jeopardized the nodulation and soybean yield under field conditions. Key words: Biological nitrogen fixation, Bradyrhizobium, compatibility, fungicide, Glycine max, HiCoat, industrial seed treatment, insecticide, polymer.

The development of practices that maintain or increases soybean yield can increase the profitability of this crop. In this context, the use of microorganism-based products in crops has been extensively studied. Among the species, Bacillus amyloliquefaciens has shown significant potential for agronomic use due to its ability to control phytoparasitic microorganisms and its effects in promoting plant growth. The aim of this study is to evaluate the effects of B. amyloliquefaciens application on soybean. Fields experiments were conducted at four sites. The experimental design used was randomized block design, with six treatments and four replications. The treatments consisted of seed treatment with B. amyloliquefaciens strain MBI600 (Integral II SC)-based product at 2.5, 5, 10, 15 and 20 mL c.p. 100 kg-1 of seeds, plus a control without treatment. The variables evaluated were plant stand, phytotoxicity, plant height, root and shoot dry mass, number of nodules and crop yield. Increasing doses of the B. amyloliquefaciens-based product promote an increase in all variables related to crop development. All doses of the B. amyloliquefaciens-based product provided an increase in soybean yield compared to the control. The dose that produces the maximum agronomic efficiency was 15 mL c.p. 100 kg-1 of seeds. Key words: Biological control, Bacillus subtilis, Glycine max, growth promoters, seed treatment.

Pre-inoculation of soybean seeds with Bradyrhizobium spp. associated with polymers could be an alternative to the conventional inoculation performed at the day of sowing. The objectives of this study were i) to determine whether the HiCoat® technology (peat inoculant + liquid inoculant + polymer) allows the survival of B. elkanii after storage of the inoculated seeds, and ii) to evaluate whether the pre-inoculation and seed treatment reduces the physiological quality of seed and soybean yield. Soybean seeds were treated with different fungicides and insecticides associated with pre-inoculation using HiCoat® and the seeds were stored at room temperature. The survival of B. elkanii was reduced over time with standard inoculation, however there was above 2 x 106 colony-forming units of B. elkanii per seed at 60 days after inoculation with HiCoat®. Seed germination, number of nodules per plant, mass of nodules, yield, number of grains per plant and number of pods per plants were not significantly affected by the pre-inoculation and seed treatments. Our findings indicated that the fungicide and insecticide associated with HiCoat® can be used to treat and to pre-inoculate seeds that can be stored for up to 71 days without compromising the nodulation of plants and soybean yield. Key words: Industrial seed treatment, biological nitrogen fixation, storage period, fungicide, insecticide, polymer, HiCoat, Glycine max.