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In a survey of fungi associated with blight of lily seedlings
grown incentral Taiwan, 151 isolates including Fusarium
proliferatum, F.oxysporum, F. solani, F. ventricosum, Pythium
spp. and Rhizoctoniasolani were obtained. F. proliferatum was
consistently isolated fromdiseased seedlings with 80.1%
frequency of appearing on 2% water agaras well as Nash PCNB
medium. Pathogenicity of F. proliferatum wasdetermined on
lily seedlings(cv. Casablanca). The bulblets of lilywere
dipped in the spore suspension(1.3 × 106 CFU/ml) of the
fungusfor 1 min. and planted in a sterilized medium. Damping-
off, yellowingand wilting symptoms of lily seedlings were
observed three weeks afterinoculation. The fungus was
reisolated from diseased tissues ofinoculated plants. Koch''s
postulates were completed and indicated thatthe tested fungus
was the causal agent. Temperature was able tosignificantly
affect the occurrence of lily seedling blight. In
growthchambers, the disease severity was markedly increased
with incrementof temperatures from 24 to 36 ℃. Lily bulblet
scales were used tobait F. proliferatum from eight culture
media. Approximately 80% ofscales buried in FF-007C, FF-007G
and TSS-01 media and 20-30% ofscales in TSC-102, TSC-103
and FF-006 media were colonized by F.proliferatum. However,
the fungus was not recovered from TSC-101 andTSS-02 media.
Six fungicides were evaluated for their effect oncontrol
of lily seedling blight caused by F. proliferatum.
Amongthose, prochloraz at 400 ug/ml, sporgon at 250 ug/ml, and
prochlorazat 400 ug/ml mixed with benomyl at 500 ug/ml were
the most effectiveto reduce the disease severity of lily
seedling blight by 58-92% andbulblet rot by 81-88% as compared
with none treatment as a control ingreenhouse tests. The same
effectiveness of prochloraz and sporgon onthe disease control
was also observed in the field tests at TaiwanSeed Improvement
Propagation Station in Central Taiwan. Antagonists ofF.
proliferatum were isolated from culture media, healthy
lilyseedlings and seeds of alfafa and radish. Nonpathogenic F.
oxysporumisolates FO-401 & FO-403, Streptomyces spp. isolates
PMS-101, 104 &106, S. griseoviridis isolates PMS-109, Bacillus
spp. isolates PMB-101, 102 & 103, B. thermoglucosidasius
isolate PMB-106 and florescentPseudomonads isolates PMP-001,
002 & 004 were able to significantlyreduce lily seedling
blight caused by the pathogen in the greenhouseand screenhouse.
Bulblets of lily were pre-treatment with sporgon anda sporgon-
tolerant anagonist PMS-101 or PMB-106 and planted in
themedium infested with F. proliferatum in the greenhouse.
After sevenweeks, the combination method was able to protect
20-50% of lilyseedlings from infection by F. proliferatum. A
field test indicatedthat bulblets treated with sporgon at
400 ppm and planted in theinfested medium pre-inoculated with
B. thermoglucosidasius PMB-106showed 20% reduction of lily
seedling blight and promoted growth ofthe seedlings.
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