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INTRODUCTION: One of the limitations of liquid inoculation with rhizobia in the planting furrow in the dry bean crop is the small number of research studies involving this type of inoculation and the establishment of application rates suitable for good performance of biological nitrogen fixation (BNF). Thus, the aims of this study were to evaluate the viability of liquid inoculation in the planting furrow in dry bean BRS Estilo and certify if the increase in the inoculation rate benefits its symbiosis with Rhizobium sp. MATERIALS AND METHODS: A field experiment was carried out in a no-till planting system in the 2014/2015 crop season in a Latossolo Vermelho distrófico in the south of Minas Gerais, Brazil, at 986 m altitude, 21º58’S latitude and 45º20’W longitude. The experimental design was randomized blocks with three replications and eight treatments, involving five application rates of liquid inoculant in the planting furrow, seed inoculation, and two controls without inoculation, one without N and the other fertilized with 80 kg ha-1 of mineral N.

INTRODUCTION: No publications were found regarding liquid inoculation in the planting furrow of dry bean, which indicates a demand for investigations to assist the producer in deciding which method of inoculation to adopt. Thus, the aim of this study was to evaluate the viability of liquid inoculation in the planting furrow and determine the best application rate of inoculant, using the dry bean cultivar IAC Alvorada. MATERIALS AND METHODS: A field experiment was conducted in a no-till planting system in the 2014/2015 crop season in a Latossolo Vermelho distrófico in the municipality of Lambari, MG, Brazil. The experimental design was randomized blocks with three replications and eight treatments, involving five application rates of liquid inoculant in the planting furrow (0, 120, 240, 480, and 720 mL ha-1), liquid seed inoculation (40 mL kg-1), and two controls without inoculation: one with N-urea (80 kg ha-1 N, ½ at sowing and ½ in topdressing, between the V3 and V4 stages of the crop cycle) and another without mineral N. The experimental unit (14.4 m2) consisted of six four-meter-length rows, spaced at 0.6 m, and the area effectively used was the four central rows. All the plots received base fertilization of 110 kg ha-1 of P2O5 (simple superphosphate) and 40 kg ha-1 of K2O (potassium chloride), mechanically applied during furrowing. In addition, all levels of inoculation received 20 kg Nurea ha-1, so as to meet the recommendations of Soares et al. (2016). Sowing was manual at the density of 15 seeds per meter and the cultivar used was IAC Alvorada, of semi-upright plant architecture and moderate resistance to anthracnose (Carbonell et al., 2008).

INTRODUCTION: Fungicide seed treatment is an important strategy for plant pathogen control in the dry bean crop. However, there are reports that it may hinder biological nitrogen fixation (BNF). The present study was carried out for the purpose of verifying the compatibility of fungicide treatment and BNF, so as to assist producers in making decisions in regard to selection of products with the least impact on biological processes and, consequently, on yield. MATERIALS AND METHODS: A field experiment was carried out in the 2014 dry season in a Latossolo Vermelho distroférrico típico in the municipality of Lavras, MG, Brazil. There was no record of inoculation prior to the dry bean crop in the area, and the population of native rhizobia capable of nodulating dry bean was approximately 103 colony forming units per gram of soil. The statistical design used was randomized blocks with three replications and a (5×3) + 1 factorial arrangement, involving five fungicides in seed treatment (Captan, Carboxin + Thiram, Difenoconazole, Fluazinam + Thiophanate-methyl, and Fludioxonil + Metalaxyl-M, all at application rates recommended by the manufacturers) and three levels of inoculation (without inoculation, seed inoculation, and inoculation in the planting furrow), plus an additional treatment with 80 kg ha-1 of N (40 kg ha-1 N at sowing + 40 kg ha-1 N at topdressin inoculant containing ±109 viable cells of the strain CIAT 899 (Rhizobium tropici) per mL was applied at the rates of 40 mL kg-1 on seeds or 300 mL ha-1 in the planting furrow. Seed inoculation occurred one hour before sowing. Sowing was manual, at a density of 15 seeds per meter. The cultivar BRSMG Madrepérola was used, with high yield potential and good level of resistance to the main diseases that occur in Minas Gerais. Plants are prostrate, of type III growth habit, with low tolerance to lodging (CARNEIRO et al., 2012). Distribution of the inoculant in the furrow was performed after sowing with the aid of a manua