ANTIFUNGAL ACTIVITY OF ENDOPHYTIC BACTERIA FROM SOYBEAN M.Z. Alimova 1 , V.V. Shurigin 2 1) National University of Uzbekistan, Tashkent, 100174, Uzbekistan 2) Institute of Microbiology of the ASc RUz, Tashkent, 100128, Uzbekistan Plant diseases are one of the major barriers to high yields, but they can potentially be
biologically controlled with PGPR and endophytic bacteria. Some of the mechanisms
that PGPR and endophytic bacteria use to counteract the harmful effects of
phytopathogens include: production of fungal cell walls degrading enzymes such as
lipase, β-1,3-glucanase, chitinase, and protease; synthesis of hydrogen cyanide, which
inhibits cytochrome C oxidase, as well as other important metalloenzymes; synthesis of
siderophores, which can prevent or reduce the proliferation of pathogens by reducing
the amount of iron available to pathogens, etc.
The aim of our research was to isolate endophytic bacteria from soybean (
Glycine max ), screen them for antifungal activity, and study the biocontrol properties of isolated
bacteria.
In total 20 isolates (SOEN-1 - SOEN-20) of endophytic bacteria were isolated from
the roots and stems of soybean. The isolated isolates were tested for their ability to
inhibit the growth of phytopathogenic fungi
Fusarium oxysporum and
Fusarium solani (Figure). The isolates SOEN-2, SOEN-9, SOEN-11, SOEN-15, and SOEN-20 inhibited
phytopathogenic fungi more effectively than other bacterial isolates and therefore were
selected for further study.
Fig. Growth inhibition of phytopathogenic fungi by endophytic bacteria from soybean
(on Petri dishes)
Selected bacteria were tested for their antifungal properties. It was revealed that all 5
isolates had certain antifungal properties. The isolate SOEN-2, which previously
showed the highest antifungal activity, was able to produce lipase, protease, glucanase,
chitinase, and HCN. The isolate SOEN-9 produced lipase, protease, chitinase, and
siderophores, while SOEN-15 produced protease, glucanase, chitinase, and HCN. The
isolates SOEN-11 and SOEN-20 had only 3 out of 6 tested antifungal properties.