Abstract:
Studies on determination of the effec
t of herbicides on survivability of Plant Growth
Promoting Bacteria have a strategic usefulness in determination of plant health and the
fate of applied agrochemicals in agroecosystem. Antimicrobial potential was assessed
using estimation of a minimum inhi
bitory concentration of the Roundup 360 SL against
Pseudomonas
sp. A quantitative analysis of bacteria was performed, and the tendency of
physicochemical changes in the mineral medium was evaluated during long
-
term
exposure to the herbicide. Furthermore, t
he antagonism of the SP0113 strain against F.
culmorum and F. oxysporum under stress conditions caused by Roundup® 360 SL was
verified. It was demonstrated that use of the undiluted and 2.6
-
fold diluted product
resulted in the inhibition of growth of the i
nvestigated strain.
Pseudomonas
sp. SP0113
showed survivability and resistance to near recommended dose concentration of
Roundup® 360 SL. The possibility of bacterial development on the
Tryptic Soy Agar
(
TSA) medium at contact concentrations of 14.4 and 5.
4 mg mL
-
1
, as per the diluents
quantity declared by the producer, indicates the role of cofactors such as: adiuvant or pH,
redox potential (
mV) or salinity.
They comprise pH change, oxidation and salinity that
may be due to the reaction of the active subst
ance of the herbicide with mineral nutrient
ingredients.
The high salinity of environment, as a result of the reactions with the
ingredients contained in the medium, is characteristic for concentrations higher than
those recommended in practice. Furthermor
e, it was found that glyphosate limits the
growth of fungi of the
Fusarium
genus, which support plant protection using strain
SP0113.
Keywords
: Biocontrol, Glyphosate, Plant growth promotion bacteria
,
PGPB
.
