Can silicon applied to correct soil acidity in combination with Azospirillum brasilense inoculation improve nitrogen use efficiency in maize?

Author(s)

Galindo, Fernando Shintate ^[1] ; Pagliari, Paulo Humberto ^[2] ; Buzetti, Salatier ^[1] ; Rodrigues, Willian Lima ^[1] ; Kondo Santini, Jose Mateus ^[3] ; Marcandalli Boleta, Eduardo Henrique ^[1] ; Leonel Rosa, Poliana Aparecida ^[1] ; Rodrigues Nogueira, Thiago Assis ^[1] ; Lazarini, Edson ^[1] ; Minhoto Teixeira Filho, Marcelo Carvalho ^[1]

Affiliation

^[1] Sao Paulo State Univ, Dept Plant Hlth Rural Engn & Soils, Ilha Solteira, SP - Brazil

^[2] Univ Minnesota, Southwest Res & Outreach Ctr, Dept Soil Water & Climate, Lamberton, MN - USA

^[3] Coll Objet, Higher Educ Inst Rio Verde, Rio Verde, Go - Brazil

• Document type: Journal article
• Source: PLoS One; v. 15, n. 4 APR 8 2020.
• Web of Science Citations: 0

Abstract

Alternative management practices are needed to minimize the need for chemical fertilizer use in non-leguminous cropping systems. The use of biological agents that can fix atmospheric N has shown potential to improve nutrient availability in grass crops. This research was developed to investigate if inoculation with Azospirillum brasilense in combination with silicon (Si) can enhance N use efficiency (NUE) in maize. The study was set up in a Rhodic Hapludox under a no-till system, in a completely randomized block design with four replicates. Treatments were tested in a full factorial design and included: i) five side dress N rates (0 to 200 kg ha(-1)); ii) two liming sources (Ca and Mg silicate and dolomitic limestone); and iii) with and without seed inoculation with A. brasilense. Inoculation with A. brasilense was found to increase grain yield by 15% when N was omitted and up to 10% when N was applied. Inoculation also increased N accumulation in plant tissue. Inoculation and limestone application were found to increase leaf chlorophyll index, number of grains per ear, harvest index, and NUE. Inoculation increased harvest index and NUE by 9.5 and 19.3%, respectively, compared with non-inoculated plots. Silicon application increased leaf chlorophyll index and N-leaf concentration. The combination of Si and inoculation provided greater Si-shoot accumulation. This study showed positive improvements in maize growth production parameters as a result of inoculation, but the potential benefits of Si use were less evident. Further research should be conducted under growing conditions that provide some level of biotic or abiotic stress to study the true potential of Si application. (AU)

• FAPESP's process: 17/06002-6 - Inoculation with Azospirillum brasilense associated with the use of silicon and nitrogen doses in corn and wheat crops
• Grantee: Fernando Shintate Galindo
• Support type: Scholarships in Brazil - Doctorate