Magnaporthe oryzae is a fungus that causes blast, which can lower the yield
for as much as 30%. Fortunately, naturally-occurring
<[isaaa.us5.list-manage1.com]
d=fd38c0f973&e=3f99440571> rice soil bacteria may provide a sustainable
solution to reduce the damage of blast disease. Rhizospheric microbiomes,
with their interactions with the plant roots, can modulate both growth
promotion and disease suppression. This study evaluates the capacity of
naturally-occurring bacteria in reducing M. oryzae infections.

Rhizospheric bacteria isolates were obtained from field grown rice plants.
These were tested for biocontrol activity against M. oryzae pathovar 70-15.
The Pseudomonas isolate EA105 displayed antibiosis with 90% reduction of M.
oryzae appressoria formation in vitro. Although hydrogen cyanide (HCN) is
associated with biocontrol pseudomonads, the biocontrol activity of EA105
seems to be independent of HCN production. In the field test, EA105 reduced
the number of blast lesions formed by 33%. Another bacteria, the Pantoea
agglomerans isolate EA106, reduced lesions by 46%. Both isolates triggered
jasmonic acid (JA) and ethylene (ET) dependent induced systemic resistance
(ISR) response in rice.

EA105 was the most effective isolate in inhibiting the growth and
appressoria formation of M. oryzae independent of cyanide production. The
application of native bacteria as biocontrol agents in combination with
current disease protection strategies could aid in global food security.


<[isaaa.us5.list-manage.com]
=0be18ecfda&e=3f99440571>
[www.biomedcentral.com]