Main content area

Sugarcane Productivity as a Function of Nitrogen Fertilization and Inoculation with Diazotrophic Plant Growth-Promoting Bacteria

Pereira, Willian, Sousa, Jailson Silva, Schultz, Nivaldo, Reis, Veronica Massena
Sugar tech 2019 v.21 no.1 pp. 71-82
absorption, costs and returns, crop yield, experimental design, fertilizer application, growth promotion, nitrogen, nitrogen fertilizers, nitrogen-fixing bacteria, plant growth-promoting rhizobacteria, root growth, sugarcane, sugars, Brazil
Sugarcane ratoons respond to nitrogen fertilizer application, but the N efficiency is low. Diazotrophs applied as a growth promoter bacterium can influence crop yield by several mechanisms, including a greater root growth and higher N absorption. The objective of the present work was to evaluate the stalk and sugar yields, and the economic index of sugarcane as a function of nitrogen fertilization and inoculation with diazotrophic plant growth-promoting bacteria (DPGPB). Two experiments were implemented in areas of two sugarcane mills in the state of São Paulo, Brazil: one in the Diamante Mill and one in the Santa Helena Mill. The experimental design was a randomized complete block with four N-fertilizer doses (0, 50, 100 and 150 kg ha⁻¹), with or without DPGPB inoculation using five replicates. The application of the inoculant promoted a productivity increase in the Diamante Mill for all treatments with N, even in the absence of N-fertilization, while at the Santa Helena Mill that occurred with the 50 kg ha⁻¹ dosage. The inoculation with DPGPB, together with the application of the 50 kg N ha⁻¹ dose, achieved the highest economic return at both mills. The application of the inoculant associated with a low dose of N-fertilizer was profitable and proven feasible for field application. The results evidenced the viability of the technology for sugarcane production, with gains in productivity and a possible reduction in nitrogen fertilization.