A Preliminary Investigation Of Turfgrass Diseases In Beijing And Hainan Golf Courses And A Taxonomic Study Of Pathogenic Fungi

Turfgrass is an important part of the golf course.The occurrence of lawn disease will not only seriously reduce the useful and ornamental value of the lawn,but also bring huge economic losses to the stadium.Fungal diseases are the main types of diseases of plant diseases in golf courses.But there is little research on them in China.In the study period from 2017 to 2018,the golf course in Beijing and Hainan Province represented the grassland of Poa pratensis,Agrostis stolonifera and Paspalum vaginatum.The fungal diseases of grass were investigated and some pathogenic fungi were classified by morphological and molecular systematic methods.The main results obtained are as follows:1.During the investigation,the survey conducted the investigation on the occurrence and distribution of diseases in 8 golf clubs in Beijing and 6 golf courses in Hainan.A total of 130 disease samples were collected,and 603 strains were isolated and purified by single spore separation method,tissue separation method and soil suspension separation method.Preliminary identification based on morphology and ITS showed that all strains belonged to 40 genera.Among them,452 strains of fungi can cause turf diseases,belonging to 16 genera.The main pathogenic fungi include Curvularia,Fusarium,Microdochium,Leptosphaerulina,Myrothecium,Phoma,Colletotrichum,Rhizoctonia and so on.2.There are differences in the main pathogens of golf courses built by cold-season grasses represented by Beijing and warm-season-built golf courses represented by Hainan.Among them,the most widespread and most abundant pathogens in Beijing golf course lawns It belongs to the genus Curvularia,followed by Myrothecium and Leptosphaerulina.The most widely distributed and most abundant pathogens in the lawns of Hainan Golf Course belong to Fusarium,and Curvularia,Microdochium.In addition,the diversity of pathogenic fungi in greens and fairways is higher than in tees and high grass areas,which may be related to the higher frequency of greening and trimming of the fairways and fairways.3.A leaf spot disease ocuured in cold-season Poa pratensis and Agrostis stolonifera was found and named as Microdochium leaf spot.The pathogen is a new fungus species: Microdochium poae.sp.nov.identified by morphology and phylogeny.The pathogenicity test found that the onset time(35 days)of the infected scutellariae was higher than that of the bluegrass(45 days).4.It was first reported that Myrothecium-like fungi can cause lawn leaf blight and root rot.A taxonomic study was performed on 84 Myrothecium-like strains obtained in this study.Using ITS,tub2,rpb2 and cmd A to construct a phylogenetic tree of Myrothecium-like strains and reference strains,combined with morphology,showed that 14 strains were identified as 4 known species(Albifimbria verrucaria,Alb.terrestris,Striaticonidium brachysporum and Paramyrothecium nigrum).The remaining strains were divided into five evolutionary branches with high support rate,which were described as five new species by morphological alignment,Alfaria humicola,Alf.poae,Dimorphiseta acuta,D.obtusa and Paramyrothecium sinense.5.Four Phoma-like strains were isolated from the rhizosphere soil of the bluegrass grassland and the high grass area.The phylogenetic tree was constructed with ITS,LSU,tub2 and rpb2 and the reference strain.It is shown that these four strains form independent branches in the genus Pyrenochaetopsis.These strains can produce sclerotia,which is different from all known species of this genus.It is described as a new species of Pyrenochaetopsis sinensis.sp.nov..