The use of PGPR as biocontrol agents is relatively low (Cook,
2000), representing about 1% of agricultural chemical sales (Lidert,
2001) while fungicides represent approximately 15% (http://
www.epa.gov). Biocontrol agents can be used in situations in
which there is no available chemical control, when conventional
pesticides cannot be used due to residue concerns, or for certified
organic production. However, the main reason for the development
of biocontrol agents is the ability of pathogens to develop
resistance to fungicides (Wilson, 1997). The different mechanisms
of action use by the biocontrol agents in biopesticides represent a
great advantage over chemicals which work on a single target.
Therefore, biopesticides can be used in rotation with pesticides
resulting in lowering the chances of pathogens to develop
resistance. In addition, biocontrol agents can also be used in
combination with reduced doses of pesticides. We do not know
what challenges may arise in the future, and it seems prudent to
develop a variety of options for disease control.
The aim of this work was to study the capacity of two bacterial
strains, individually or in combinations, to protect rice against
natural blast disease incidence under field conditions. In addition,
the effect of these strains on rice production was evaluated
determining production (tonnes per hectare) and quality (weight
of 1000 seeds and percentage of intact grains after milling).