Componentes do rendimento e qualidade de sementes de feijão submetidas a co-inoculação com rhizobium tropici e azospirillum brasilense

Abstract

The present study aimed to evaluate the yield components, physiological quality and physical characteristics of common bean seeds of the IPR Urutau cultivar, subjected to co-inoculation with Rhizobium tropici and Azospirillum brasilense. The experiment was conducted in Erechim/RS, in a randomized block experimental design. The following treatments were tested: T1: Control; T2: Mineral nitrogen (N); T3: Seed treatment (TS) with Rhizobium tropici; T4: TS with Azospirillum brasilense; T5: TS with Rhizobium tropici and Azospirillum brasilense; T6: TS with Rhizobium tropici + mineral N; T7: TS with Azospirillum brasilense + mineral N; T8: TS with Rhizobium tropici and Azospirillum brasilense + mineral N; T9: TS with Rhizobium tropici and Azospirillum brasilense + mineral N + Azospirillum brasilense foliar. The variables analyzed in the experiment were: yield components, productivity, number of pods per plant, number of seeds per plant, weight of 1000 seeds, physiological quality, germination, accelerated aging and electrical conductivity, physical quality length, thickness and width of the grain. Productivity ranged from 1,990.3 kg per hectare in the control to 2,624.1 kg per hectare in the treatment with TS, Azospirillum and mineral N, representing an increase, however, this difference was not statistically significant. Regarding physiological quality, electrical conductivity showed an important difference (p ≤ 0.05), being lower in treatments that combined mineral N with inoculation. In the accelerated aging test, seeds from the treatment with Rhizobium, Azospirillum, mineral N and foliar application of Azospirillum showed a high rate of normal seedlings, higher than those from the treatment with Azospirillum alone. Regarding the physical characteristics of the grains, length, width and thickness, there were no significant differences between the treatments. Thus, even though the yield components were not statistically influenced, the seeds produced with the combination of coinoculation and nitrogen fertilization showed greater physiological vigor.