Antioxidant activity and induction of mechanisms of resistance to stresses related to the inoculation with Azospirillum brasilense.
Arch Microbiol
; 200(8): 1191-1203, 2018 Oct.
Article
in En
| MEDLINE
| ID: mdl-29881875
ABSTRACT
We investigated the effects of Azospirillum brasilense strains Ab-V5 and Ab-V6 in the induction of mechanisms of systemic acquired resistance (SAR) and induced system resistance (ISR) on maize (Zea mays L.) plants. Under normal growth conditions, the treatments consisted of the standard inoculation of cells at sowing, and leaf spray of cells or their metabolites at the V2.5 growth stage; under saline stress (170 mM NaCl), the treatment consisted of standard single and co-inoculation of A. brasilense and Rhizobium tropici. The main compounds in the Azospirillum metabolites were identified as indole-3-acetic acid (IAA) and salicylic acid (SA). Under normal conditions, A. brasilense cells applied at sowing or by leaf spray increased the activities of catalase (CAT), superoxide dismutase (SOD), and malondialdehyde (MDA) in leaves, and of ascorbate peroxidase (APX) in roots; however, interestingly, in general the highest activities were observed by leaf spray of metabolites. Under normal conditions, the highest levels of salicylic acid (SA) and jasmonic acid (JA) were achieved in leaves by leaf spray of metabolites, of SA in roots by leaf spray of cells, and of JA in roots by standard inoculation and leaf spray of metabolites. Under saline stress, plant protection occurred via SA and abscisic acid (ABA), but not JA. In general, inoculation resulted in further increases in SA in leaves and roots, and ABA in leaves. We hypothesize that A. brasilense confers protection to maize plants by simultaneous induction of JA and SA pathways, and, under saline stressing conditions, by SA and ABA pathways.
Key words
Full text:
1
Collection:
01-internacional
Database:
MEDLINE
Main subject:
Azospirillum brasilense
/
Zea mays
/
Antioxidants
Country/Region as subject:
America do sul
/
Brasil
Language:
En
Journal:
Arch Microbiol
Year:
2018
Document type:
Article
Affiliation country:
Brazil
Publication country:
ALEMANHA
/
ALEMANIA
/
DE
/
DEUSTCHLAND
/
GERMANY