Belgrade : University of Belgrade, Institute of Botany and Botanical Garden Jevremovac
Abstract
Plant diseases caused by fungal pathogens can lead to major
economic losses in agriculture. Th e genus Alternaria includes
saprobic, endophytic and pathogenic species that may cause
various plant diseases such as blight disease. Symptoms of
Alternaria blight include the presence of irregular, oft en circular, brown to dark brown coloured leaf spots. Alternaria
spp. also cause collar rots, stem lesions, tuber and fruit rots
of their respective hosts. In addition, bacteria are one of the
most frequently biocontrol agents used to protect plants from
diseases. Bacillus species control disease through a variety of
mechanisms. Bacterial antagonists might act as inhibitors of
growth, development and reproduction of pathogen, or as inducers of host resistance in plant. Th e objective of this study
was to examine in vitro antifungal activity of ten antagonistic
Bacillus strains from collection of Department for Microbiology of Institute of Field and Vegetable Crops, Novi Sad. Strains
were originally isolated from the soil samples collected from
several localities of Vojvodina Province. Antifungal activity of
Bacillus strains against Alternaria padwickii, A. dauci and A.
linicola, obtained from rice, carrot and linseed, respectively
was tested using a dual plate assay. Th e results confi rmed that
all tested Bacillus strains showed antifungal acivity against Alternaria spp. Th e highest antagonistic activity was exhibited
by B. pumilus B11 (45.71% to 51.25%), B. subtilis B13 (45.71%
to 49.37%) and B. subtilis B32 (45.71% to 52.08%), while B.
pumilus B23 had the weakest antifungal activity. B. safensis B2
(35.24% to 48.33%), B. pumilus B21 (40.95% to 48.75%) and
B. pumilus B22 (33.50% to 49.17%) also demonstrated good
antifungal potential. A. dauci was the most sensitive fungus,
while the most resistant was A. linicola. Obtained results indicate the possibility of usage of the most eff ective Bacillus
strains as potential biocontrol agents of plant diseases caused
by Alternaria sp
