Keywords :
Actinomycetes,
Chitin degrading enzymes,
Biological control,
Plant pathogens,
Strain improvement
บทคัดย่อ :
Two hundred isolates of actinomycetes isolated from soil samples in Sakaerat Biosphere Reserve
and Suwanvajokkasikit Field Corps Research Station were tested for the ability of chitinase production
and growth inhibition of three phytopathogenic fungi; Fusarium sporotrichiodes, Rhizoctonia solani
and Sclerotium rolfsii. The result showed that SG4 and SG5 strains gave the consistent inhibitory effect
against all three fungal pathogens inoculating preculture for 0, 5 and 10 days. It was found that inoculating
preculture for 10 days showed the most antagonist effect and nine isolates of actinomycetes showed the
highest inhibition of the tested strains, while only seven strains remained when the strain was meanwhile
cultures in the plates with and without chitin. To increase the ability on antifungal activity, the selected
isolates were irradiated with gamma radiation. Thirty five out of 173 isolates showed higher inhibitory
effect on three phytophatogenic fungi tested than the wild type strains. Three isolates of mutant strains,
SJ9I-15, SG4I-17 and SG4I-38 and two isolates of wild type strains, SJ9 and SG4, were selected for
controlling phytopathogenic fungi in the greenhouse.
เอกสารอ้างอิง :
Rugthaworn, P., Dilokkunanant, U., Sangchote, S., Piadang, N., & Kitpreechavanich, V. (2007). A search and improvement of actinomycete strains for biological control of plant pathogens. Agriculture and Natural Resources, 41(5), 248-254.
