kvalitet

Chaenomeles japonica and Cotoneaster horizontalis 93
nitrofurantion, kanamycin and amykacin, and streptomycin and eritromycin were
30-35 mm and 25-30 mm, respectively.
DISCUSSION
Bacterial fireblight is very serious problem in Serbia. Few years after its first
recording on apple, pear and quince in Serbia (Arsenijević, 1990), the causer
agent (E.amylovora) was isolated from from spontaneous and ornamental plants:
– Pyracantha coccinea (Gavrilovic and Arsenijevic, 1998), C. japonica and C.
horisontalis (Balaž Jelica, 2000; Balaž Jelica et al., 2004). The disease occurrence
on C. japonica and C. horisontalis in 2000 was favored by high temperatures
during flowering period of apple in the nearby oarches.
Morphological, cultural, biochemical, physiological and serological
characteristics and sensitivity to antibiotics showed that our strains obtained
from C. japonica and C. horizontals were identical to referent NCPPB 595
and JK strains from apple. Bacteriological characteristics of our strains were in
accordance to the results of other researches who studied numerous E. amylovora
strains of pomaceous fruits from different geographic area of Europe and USA.
Further investigations on molecular level or by enrichment serological methods,
would perhaps show some differences between strains.
All our strains were sensitive to aplied antibiotics except to vancomycin.
Morgan and Goodman (1955) found aureomycin, neomycin, streptomycin,
polymyxin, streptotrichin, viomycin and chloromycetin to be effective to
E.amylovora in laboratory conditions. Penicillin didn’t inhibite growth of
E.amylovora in vitro according to Billing et al. (1961). On the other hand,
Rudolph (1946) found penicillin to inhibit pathogen in vitro, but its control of
Fire blight failed in the field experiments. Martinec and Kocur (1964) found
that all 49 tested strains of E.amylovora were sensitive to chloramphenicol,
erytromycin, neomycin, streptomycin and teracycline, while 24 were sensitive to
chlorotetrcycline.
Although many antibiotics inhibit growth of E.amylovora in vitro, only a few
have practical value for the field application (mainly streptomycin and sporadicly
oxytetracycline and kasugamycin were used).