Application methods of Azospirillum brasilense in first- and second-crop corn

Abstract

This study investigated whether inoculation of Azospirillum brasilense in the seeds or sowing furrow could reduce the need for nitrogen fertilizer application in the corn grown in the first and second crop harvest. The experiments were conducted, in the municipality of Chapadão do Sul, MS, Brazil, in the first crop harvest (2014/2015) and in the second crop harvest (2016). The early maturity hybrids CD 384 HX and P3132H were used in the first and in the second harvest corn, respectively. In both experiments, the experimental design was the randomized blocks with eight treatments and three repetitions. At the silking (R1 stage), the leaf N concentration, relative chlorophyll index and nitrate reductase activity were measured, at the physiological maturity (R6 stage), the plant height, first ear insertion height, one hundred grain mass, grain yield and grain N concentration were measured. In the first crop harvest, the application of Azospirillum brasilense at the sowing furrow resulted in higher N concentration and relative chlorophyll index in corn leaves, while the inoculation of A. brasilense in the seeds provided higher N concentration in the grains. The nitrate reductase activity in corn leaves was lower when inoculation was performed. In the second crop harvest, the inoculation did not affected the N concentration in the leaves and in the grains, the relative chlorophyll index and the growth of corn plants. Inoculation in the sowing furrow associated with the application of 20 kg N ha-1 at sowing and 120 kg N ha-1 at topdressing resulted in lower nitrate reductase activity.

Особливості Управління Врожайністю Кукурудзи В Умовах Нестійкого Зволоження

“…Застосування стимуляторів росту також стало важливим компонентом управління врожайністю. Інокуляція насіння кукурудзи чи внесення у ґрунт азотфіксуючих бактерій Azospirillum brasilense призвело до збільшення концентрації азоту в листках рослин та концентрацію хлорофілу й може істотно зменшити необхідність використання азотних добрив [2], збільшити врожайність кукурудзи на 24…30 % чи залежно від умов проведення досліджень на 4…7 ц/га [6,12]. Комплекс органічних, мінеральних добрив, хімічних меліорантів та гумінових речовин може збільшити врожайність зерна до 15 % [3], хоча можуть призвести й до негативних наслідків для проростання [15].…”

Nitrogênio e formas de aplicação de Azospirillum brasilense em milho cultivado em solo arenoso

“…graças às respostas metabólicas, dentre elas o maior desenvolvimento das raízes, permitindo uma maior recuperação do N que foi utilizado na adubação. O aumento nas raízes ocorre devido a uma maior atividade hormonal, principalmente de auxina (Alvarez et al, 2019).…”

Milho para silagem em sucessão a plantas de cobertura e Azospirillum brasilense em solo arenoso

“…Esse favorecimento ocorre devido às respostas metabólicas, dentre elas o maior desenvolvimento das raízes, permitindo uma maior recuperação do N que foi utilizado na adubação. Esse melhor desenvolvimento das raízes ocorre devido a uma maior atividade hormonal, principalmente de auxina (Alvarez et al, 2019).…”