International Journal of Advanced Engineering Research and Science (IJAERS) ISSN: 2349-6495(P) | 2456-1908(O) Vol-8, Issue-4; Apr, 2021 Journal Home Page Available: https://ijaers.com/ Journal DOI: 10.22161/ijaers Article DOI: https://dx.doi.org/10.22161/ijaers.84.26 www.ijaers.com Page | 217 Efficiency and response of corn cultivars to nitrogen, associated or not with Azospirillum brasilense Vanderlan Carneiro Dias 1 , Joênes Mucci Peluzio 1 , Flávio Sérgio Afférri 1 , Maria Dilma de Lima 1 , Domingos Bonfim Ribeiro dos Santos 1 , Guilherme Benko 1 , Weder Ferreira dos Santos 2* , Layanni Ferreira Sodré Santos 2 , Adriano Silveira Barbosa 2 , Lucas Alves de Faria 2 1 Federal University of Tocantins, Palmas, Tocantins, Brazil. 2 Federal University of Tocantins, Gurupi, Tocantins, Brazil. *Corresponding Author Received: 09 Jan 2021; Received in revised form: 06 Mar 2021; Accepted: 26 Mar 2021; Available online: 26 Apr 2021 ©2021 The Author(s). Published by AI Publication. This is an open access article under the CC BY license (https://creativecommons.org/licenses/by/4.0/). Keywords— Zea mays, natural fixation, nitrogen. Abstract— Green corn is an economic and social alternative for small and medium-sized farmers. However, the high cost of the insums, especially in relation to the use of nitrogen, has advanced studies with nitrogen-fixing bacteria. This study evaluated commercial maize cultivars for the production of green ears, responsive and efficient to nitrogen use, with and without application in Azospirillum brasilense seeds. Two trials were installed in the agricultural years 2019/20 and 2020/21 in soweds carried out on 12/04/2019 and 10/12/2020 in this order, at the Federal University of Tocantins, Palmas-TO. In each trial, the experimental design was randomized blocks, with three replications, being the treatments arranged in subdivided plots, where the treatments involving the processes with inoculation of seeds with the bacterium Azospirillum (C Az) and without inoculation of seeds (S Az) were allocated in the plots, two doses of nitrogen (30 and 120 kg ha -1 N, considered as low and high N, respectively) and in the subplots eight corn cultivars were allocated in the subplots. Joint variance analysis was performed for each of the seed inoculation processes (C Az and S Az) and then the efficiency and response of corn cultivars were studied for the use of N for each process. The inoculation of seeds with the bacterium promoted changes in the efficiency and response of cultivars regarding the use of nitrogen. The cultivar BRS-3046 was the most important for the cultivation of green ears, since it was efficient and responsive to the use of nitrogen with Azospirillum brasilense. I. INTRODUCTION The production of green corn (Zea mays) is a source of income and food, both for human and animal feed, being used by the consumer market in grain or in natura "green ears" and in the canned industry [1]. In Brazilian cuisine, it is marketed in free fairs, grocery stores and supermarket chains and even on the borders of highways in the forms of roasting, cooked etc. [2]. In the Northern region of Brazil, specifically in the state of Tocantins, the low productivity of corn occurs, among other factors, due to the presence of high temperatures, low technological level, scarcity of