مطالعه ميكروسكوپي تعامل پاتوژن -ميزبان در نارون چتري مايه زني شده با قارچ Ophiostoma novo - ulmi

Microscopic study on host-pathogen interaction in Ulmus carpinifolia var. umbraculifera Rehd. inoculated by Ophiostoma novo-ulmi

Introduction: Duch elm disease caused by Ophiostoma novo-ulmi is one of the most important vascular diseases in last some decades. Aim: However, it is necessary to survey its different aspects such as distribution, biology, pathogenicity, management and histopathology. In order to investigate host-pathogen interaction, this research was carried out with title mocroscopic study on host-pathogen interaction in Ulmus Carpinifolia Var. Umbraculifera Rehd. Inculated by Ophiostoma novo- ulmi. Materials and methods: When withered and dieback symptoms were occurred 8 weeks after inoculation by Ophiostoma novo-ulmi against seedlings, transversal section were prepared from lower parts of withered and dried folige. Then. Very thin transversal section were prepared and after different stages of staining, microscopic slids were prepared. Result: The results of microscopic investigations showed that the causal agent of disease has caused disordered in physiology and flowing of vascular sap through spreading into vessels, obstruction of xylem vessels and their destruction. The results also showed that seedlings with tylose production caused obstruction of vessels and prevented spreading of pathogen. Conclusion: Pathogeneses and defensive mechanisms associated with host-pathogen interaction and their roles at susceptibility rate of seedling Ulmus Carpinifolia Var. Umbraculifera Rehd to this disease were discussed in this paper.