Evaluation of the residual nitrogen effect liberated by the soybean straw on the maize yield in the second crop

Abstract

The objective of this study was to evaluate the effect of Nitrogen (N) liberated by the early\xa0soybean straw, inoculated in function of dosage and application means of the inoculant, over the\xa0vegetative growth and grain yield of second crop corn, in succession. The hybrid corn Land® was\xa0sowed in January 1st, 2017 over the soybean straw from a former experiment in Sinop (MT). The trial\xa0design used was randomized blocks (DBC) with four replications and ten treatments. For the soybean\xa0treatments: witness without N application (only inoculated with Bradyrhizobium japonicum and B.\xa0elkanii); for the other treatments, it has been applied the dosage of 10 kg ha-1 of N in different phenological\xa0stages and ways of application (by haul at sowing; in V2 by haul and leaf fertilization; in V4\xa0by haul and leaf fertilization; in R1 by haul and leaf fertilization; in R2 by haul and leaf fertilization).\xa0Plant height, stalk diameter, total chlorophyll and grain yield were evaluated. The N mineralization\xa0from the soybean straw is not enough to fulfill the corn N demand. Even though there were no significant\xa0differences among the treatments, the N application in V2 and R1 stages, by topdressing on\xa0former soybean, provided the highest grain yield of corn.