سال انتشار: ۱۳۸۴

محل انتشار: چهارمین همایش ملی بیوتکنولوژی ایران

تعداد صفحات: ۳

نویسنده(ها):

S Aghighi – Department of Plant Pathology, College of Agricultural Sciences, Bahonar University of Kerman.
G.H Shahidi Bonjar – Department of Plant Pathology, College of Agricultural Sciences, Bahonar University of Kerman.
P Rashid Farrokhi – Department of Agronomy and Plant Breeding, College of Agricultural Sciences, Bahonar University of Kerman.
A Ayatollahi Moosavi – Department of Mycology and Parasitology, College of Medicine, Medical University of Kerman, Kerman.

چکیده:

Soil Actinomycetes, particularly (Streptomyces spp.), are valuable tools in biotechnology by providing special genes in development of transgenic plants resistant to phytopathogens. Actinomycetes microflora of the Iranian soils has not been very well explored in searching for biofungicides or use of their antifungal genes for genetic engineering of crops. In our survey, among 156 soil inhabitant Actinomycete isolates, strain 101 revealed strong antagonistic and chitinolytic activities. Antifungal activity of this strain against (Alternaria solani, Alternaria alternata, Fusarium solani) and four phytopathogenic isolates (Pistachio, Cotton, Olive and Potato) of (Verticillium dahliae) was assayed. Strain 101 was able to growth on chitin minimal medium agar and utilized chitin as sole source of carbon and nitrogen and was physiologically identified as a new strain of (Streptomyces plicatus) from Kerman, Iran. It was propagated in fed-batch-cultures and active crude was prepared upon which some biological characterizations performed. The active metabolite (s) was polar, soluble in H2O and methanol but insoluble in non polar solvents. Antifungal activity composed of two types, mycelial inhibition, inhibition of microsclerotia and melanin biosynthesis. Thermal inactivation points of active phases were 70°C and 90°C. Antifungal (chitinase) gene from (S. plicatus) was evaluated a useful candidate for development of recombinant DNAs in genetic engineering of agriculturally important crop plants for increased tolerance against phytopathogenic fungi.