The infection process of Rhizoctonia solani in Zoysia japonica

Abstract:

[Objective] In order to figure out the infection relationship between Rhizoctonia solani AG1 IA and Zoysia japonica, and provide a theoretical basis for further research on pathological infection mechanism, as well as molecular breeding for disease resistance of turfgrass. [Methods] Z. japonica was infected by R. solani AG1 IA through root inoculation, the disease incidence of leaves and plants, disease index were analyzed. Meanwhile, the infection process and methods was studied using histological staining transparent technology and paraffin sections. [Results] The hyphae of R. solani AG1 IA hyphae firstly adsorbed, and then grew directionally along the surface of the tissue, followed by the formation of infection cushion. The hyphae penetrated the tissues through intercellular spaces and invaded the cortical cells, and gradually extended inward the vascular system except xylem vessels. The underground and ground part of Z. japonica showed disparate host response against R. solani AG1 IA. [Conclusion] Infection process of R. solani include adsorption, directional growth, penetration, colonization. The infection of R. solani mainly cause Z. japonica leaves lesions. There are no direct correlation between Z. japonica lesions and infecting hyphae. This might indicate that R. solani has the complex mechanism of pathogenicity.