نوع مقاله : پژوهشی- فارسی
نویسندگان
1 گروه زیست شناسی، دانشکده علوم پایه، واحد تهران مرکزی، دانشگاه آزاد اسلامی، تهران، ایران
2 بخش بیوتکنولوژی میکروبی، پژوهشگاه بیوتکنولوژی کشاورزی ایران (ABRII)، سازمان تحقیقات، آموزش و ترویج کشاورزی (AREEO)، کرج، ایران
3 بخش بیماریهای گیاهی، موسسه تحقیقات گیاهپزشکی کشور، سازمان تحقیقات، آموزش و ترویج کشاورزی (AREEO)، کرج، ایران
4 بخش بیوتکنولوژی میکروبی، پژوهشگاه بیوتکنولوژی کشاورزی ایران (ABRII)، سازمان تحقیقات، آموزش و ترویج کشاورزی (AREEO)، کرج، ایران گروه
چکیده
کلیدواژهها
موضوعات
عنوان مقاله [English]
نویسندگان [English]
Despite Capsicum annuum L. being one of the most valuable greenhouse crops, soil-borne diseases, especially root rot caused by Rhizoctonia solani, are significant limitations to its productivity. In this study, the ability of 13 selected actinomycete strains to inhibit the growth of R. solani mycelia in vitro and to control the disease in a greenhouse setup was evaluated in comparison with the chemical fungicide tebuconazole on three commercial bell pepper cultivars (Scarlet, Lomus, and Semer). Results of dual culture assays revealed that all strains significantly suppressed fungal growth, with the highest suppression recorded for strains 603 (80%) and 3513 (70%). In the greenhouse experiments, strain 603 significantly increased the root dry weight and decreased disease severity in the Semer cultivar from 60% in the infected control to less than 30%. In the Scarlet cultivar, the maximum protective index was recorded for strain 3513, while in the Lomus cultivar, both strains outperformed the fungicide treatment. In addition, seedling mortality due to the disease was reduced to zero in plants treated with either bacterial strain. Both strains demonstrated iron-chelating activity and were non-hemolytic. Results of molecular analysis indicated that strain 603 has the potential to induce plant defense responses through upregulation of the GST gene. In conclusion, the results of this study clearly showed that strains 603 and 3513 significantly reduced (p < 0.05) disease severity and disease-induced mortality while improving plant growth parameters, thus establishing their excellent potential as biocontrol agents for the effective management of Rhizoctonia damping-off in bell pepper.
کلیدواژهها [English]