Adubação nitrogenada associada à inoculação com <i>Azospirillum brasilense</i> na cultura do milho

Abstract

Resumo -A adubação nitrogenada por fertilizantes minerais é um dos principais manejos utilizados pelos produtores como forma de suprir as necessidades das plantas com esse nutriente. O objetivo foi avaliar o efeito da adubação nitrogenada sobre o crescimento de plantas híbridas de milho associadas com bactérias diazotróficas endofíticas. O experimento foi conduzido em casa de vegetação, por um período de 90 dias, com substrato natural. O delineamento experimental utilizado foi em blocos casualizados, sendo que os tratamentos foram dispostos no esquema fatorial 2 x 4, com quatro repetições e constituídos, pela inoculação e não com o produto comercial a base de Azospirillum brasilense combinados com quatro diferentes doses de nitrogênio (0; 0,0714; 0,1428 e 0,2142 g kg -1 ). Foram avaliados os dados relativos à altura, diâmetro do colmo, área foliar, teor de clorofila, massa seca das folhas, colmo e raiz das plantas de milho, cultivadas em condições de casa de vegetação. As plantas de milho BM 3061 inoculadas com Azospirillum brasilense respondeu positivamente as doses de nitrogênio. Porém a dose que 0,1428 g kg -1 de N foi a que apresentou melhor comportamento, podendo ser indicada para adubação do milho.Palavras-chave: Sulfato de Amônio; Zea mays L.; Fixação Biológica do Nitrogênio; Bactéria Diazotrófica. Nitrogenated fertilizer associated with inoculation with Azospirillum brasilense in maize cultureAbstract -Nitrogen fertilization by mineral fertilizers is one of the main managements used by producers as a way to supply the needs of plants with this nutrient. The objective was to evaluate the effect of nitrogen fertilization on the growth of hybrid maize plants associated with endophytic diazotrophic bacteria. The experiment was conducted in a greenhouse for a period of 90 days, with natural substrate. The experimental design was a randomized complete block design, and the treatments were arranged in a 2 x 4 factorial scheme, with four replications, and inoculated with the commercial product based on Azospirillum brasilense, combined with four different doses of nitrogen (0; 0.0714; 0.1428 and 0.2142 g kg -1). Data on height, stem diameter, leaf area, chlorophyll content, leaf dry matter, stem and root of maize plants, were evaluated under greenhouse conditions. The BM 3061 maize plants inoculated with Azospirillum brasilense responded positively to the nitrogen doses. However, the dose that 0.1428 g kg -1 of N was the one that presented the best behavior and could be indicated for fertilization of maize.

Technical efficiency of forage production from residues of green corn (Zea mays L.) in Sergipe, Brazil

“…30, 2.35, and 2.46 m, respectively (Table 1). This increase in height specificallyrelates to the effects that nitrogen promotes on cell division, plant metabolism, and photosynthetic processes (Morais et al, 2017).…”

“…The DM content is usually related to the age of the plant, therefore older plants will produce high DM content with low digestibility such as lignin, cellulose, hemicellulose, and other nutritional components (Burin, 2018). In an experiment carried out by Morais et al (2017), it was observed that DM of leaves and stems had a significant effect with N fertilization in corn, unlike the combination of N with inoculation, with no statistic effect. There was also no statistically significant effect of inoculation via seed, sowing furrow, and leaf on the total dry matter of corn (Andrade et al, 2019).…”

“…biomass production, plant height, and corn yield (Skonieski et al, 2017) through root development, promoting greater nutrient uptake and consequently acting on crop development. Nevertheless, the sole use of the bacteria does not completely replace N fertilization in the plant (Morais et al, 2017).…”

Azospirilla and Nitrogen Fertilization to Promote Maize Seed Development and Yield

“…However, inoculation benefits were higher (+21%) at yields lower than 3000 kg ha -1 and at lower N rates (≤ 50 kg ha -1 , +8%). Such differences in response to maize inoculation can also be attributed to factors such as the number of viable cells per seed, the cell viability, the plant genotype, the Azospirillum genus, the inoculant physical placement, the biochemical characteristics and competition with other microorganisms native to the soil [30,31].…”