Fusarium root and crown rot disease of Turfgrass

Turfgrasses have been recognized for their importance to our quality of life for many years. Today, they are cultured as a main component of cool-season grasses in the landscape and sport fields in Iran. Turfgrasses are susceptible to Fusarium species. To study the role of Fusarium species as the causal agents of foliar blight, crown and root rot of turfgrass, samples were collected from infected turfgrass plants from different areas in landscapes of Tehran, Ardebil, Khorasan and Khoozestan provinces during 2009 - 2010. Based on morphological and physiological characteristics and the diagnostic keys a total of 101 isolates seven species of Fusarium recovered. These include: F. solani (33%), F. chlamydosporum (8%), F. proliferatum (2%), F. graminarum (13%), F. oxysporum (8%), F. subglutinans (9%) and F. compactum (28%). Fusarium isolates were found pathogenic using their conidial suspensions in the soil of the one month- old turfgrass seedlings used in Iran as Baronburg trade mark which is mixed of Lolium perenne, Festuca rubra and Poa pratensis seeds in the greenhouse conditions. Based on the more pathogenic effect, the order of Fusarium species were: F. solani, F. subglutinan, F. chlamydosporum, F. oxysporum, F. compactum, F. graminearum, F. poliferatum, respectively. Pathogenicity test for above Fusarium isolates against five major genera of turfgrasses including: Poa pratensis (Kentucky bluegrass), F. rubra (Fescue), Agrostis stolonifera (Bentgrass), Lolium perenne (Rye grass) and Cynodon dactylon (Bermudagrass)– were also performed under greenhouse conditions. The results showed that Rye grass, Fescue, Kentucky bluegrass Bermuda grass and Bentgrass were more resistant to isolates of tested Fusarium species, respectively Pathogenicity test for any of five turfgrasses against above Fusarium species was performed on one month- old seedlings under greenhouse conditions. The virulence of the fungal isolates was evaluated.