Pathogenicity Of Gaeumannomyces Graminis (Sacc.) Arx & Oliver To Turf-grass & Identification Of Root Disease Pathogen On Turf In Central Shasnxi

Take-all disease of turf-grass, infected by Gaeumannomyces graminis, is one of important root disease in turf. G. graminis var.avenae is widely distributed in Europe and America, but does not occur in China. G. graminis var.tritici was the serious pathogen in part area of China. Recently the demands of turf-grass are enhanced, turf-grass are imported from overseas mainly. The pathogenicity of Ggt (Chinese isolates) to turf-grass is needed to evaluate. Pathogenicity of Ggt, Gga (Finland isolates), Ggg and Ggm to turf-grasses, was tested by seedling-inoculation method. The following results are obtained1. Chinese isolates of Ggt have pathogenicity to turf-grasses, including Lolium perenne .,Festuca arundinacea, Lolium multiflorum, Festuca ovina, Poa pratensis, Poa. nemoralis, Agrostis tennis, Agrostis palstriss, Cynodon dactylom. Agrostis tennis, Agrostis palstriss, Cynodon dactylom. were the most susceptible, and the same to some cultivars of Poa pratensis and Lolium perenne., Festuca arundinacea, Lolium multiflorum, Festuca ovina, Poa nemoralis, were middling susceptible. The typical symptom, rhizome, crown, the first leaf sheath discolored and extensively rotted, the upper leaves became yellowing and the height of diseased plants remarkably reducing are very evident, even the diseased plants perished. Pathogenicity of Ggt ( Chinese isolates ) was equal to that of Gga, reported latter, and even higher.2. Finland isolates of Gga have the pathogenicity to turf-grasses, including Lolium perenne.,Festuca arundinacea, Lolium multiflorum, Festuca ovina, Poa pratensis, Poa nemoralis, Agrostis tennis, Agrostis palstriss, Cynodon dactylom. Agrostis tenuis, Agrostis palstriss, Cynodon dactylom. were the most susceptible, and the same to some cultivars of Poa nemoralis, Lolium perenne. Festuca arundinacea, Lolium multiflorum, Festuca ovina, , Poa pratensis were middling susceptible. The typical symptom, rhizome, crown, the first leaf sheath discolored and extensively rotted, the upper leaves became yellowing and the height of diseased plants remarkably reducing are very evident, even the diseased plants perished.3. The pathogen, caused take-all disease of wheat, Ggt, have pathogenicity to turf-grass, which have been potential dangerous to the turf-grass No reports on take-all of turf can be found in our country, Therefore we have much work to do in order to prevent the pathogen from coming into the turf. Gga has high pathogenicity to the turf-grasses, which is utilized extensively at present, and did not occurred in China yet. The strictly quarantine is necessary.4. Pathogenicity of Gaeumannomyces graminis, including Gga, Ggt, Gg var.graminis and Gg.var.maydis, to gramineous forage, including Dactylis glomerata, Bromus inermis, Clinelmyus dahuricus, Festuca arundinacea, Agropyrum cristatum, was evaluated by seedling-inoculation. Ggt and Gga had middling pathogenicity to gramineous forage. Ggg has poor pathogenicity to the gramineous forage, embodied in the field of poor severity to the roots and leaf sheath, as well as little reducing on height. And the same to Ggm.5. Some species and cultivars, having better resistance to Ggt and Gga, were found and should be popularized for turf. The species and cultivars, including Lolium perenne ( Delaware. PH.D, Lowgrow ), Festuca arundinacea ( Pride, Vegas ), Poa pratensis ( Alpine, Barlin, Bluemoon, Conni ) have better resistance to Ggt, and Lolium perenne ( Delaware, Topgun, Accent, Taya, PH.D, Lowgrow), Festuca arundinacea ( Pride, Triple A, Mranglell, Vegas ), Poa pratensis ( Alpine, Conni) had the better resistance to Gga.6. We surveyed the occurrence of the root, crown and leaf sheath disease, and nine pathogens had been identificated. The results were following: Colletotrichum graminicola(Ces.) Wilson, Drechslerapoae (Baudys) Shoem. Drechslera dictyoides (Drechsler) Shoem. (=D.dictyoides Drechslera f. sp. Dictyoides Shoem), dictyoides (Drechsler) Shoem. Drechslera andersenii Lam.[= D. dictyoides...