Efectos de diferentes prácticas de manejo en la nodulación y en el rendimiento del cultivo de soja

this study examines the effect of crop sequence, inoculation and fertilization on the behavior of nodulation and soybean yield in extensive farming systems of the central area of cordoba. the experience was developed during two campaigns with different hydric stress levels, in fields under no-tillage systems, both in the soybean-soybean and corn-soybean sequences. the effect of the application of no nitrogen fertilizers and inoculate were analyzed. during the r5 soybean growth stage the number and fresh weight of nodules in main and secondary roots and the percentage of functional nodules were measured; grain yield and root morphology were also evaluated. the average weight of the main root nodules was the most sensitive variable to the different cultural practices. the corn-soybean rotation was the main factor that favored the nodular system. the effect of fertilization and inoculation was not significant for most of the variables measured. the weight of main root nodules during the wetter campaign, was double that in the dry campaign. grain yields did not show differences between the treatments considered nor were they correlated with nodulation patterns. the greatest nodulation appeared in fields with less nitrogen availability.