Inoculation of Wheat With Azospirillum spp.: A Comparison Between Foliar and In-furrow Applications

The present work aimed to evaluate the agronomic performance of wheat grown under no-tillage system and submitted to different doses and methods of inoculation with Azospirillum spp. Eight treatments were tested: 1) control; 2) half N dose; 3) full dose of N; 4) half N dose + standarded inoculation by seeds (200 mL ha-1); 5) half N dose + in-furrow inoculation (200 mL ha-1); 6) half N dose + in furrow inoculation (300 mL ha-1); 7) half N dose + inoculation by foliar spraying (200 m ha-1) and 8) half N dose + inoculation by foliar spraying (300 mL ha-1). The following parameters were evaluated: number of tillers per plant, number of grains per spike, shoot dry biomass, weight of thousand seed mass, hectoliter weight, nitrogen content in grains, nitrogen content in shoot dry matter as well as crop yield. Our results showed that the supply of the half dose of mineral N associated to foliar inoculation with Azospirillum at the dose of 300 mL ha-1 provided positive results on wheat yield, confirming the bacterial ability to fix N. However, only the full mineral N fertilization stood out as the best N fertilization management.