| Tilletia contraversa as the organism causing dwarf bunt of winter wheat, is a destructive fungi to wheat, it became an important international quarantine object because it was extreme-ly difficult to control and survival in a bad environment. Because TCK plays an important part in international food commerce, so lots of scholars at home and abroad do a lot of work in identification and treating of TCK. It’s difficult to make a distinction between TCK, TCT and TFL only by morphology, traditional methods to distinct TCK from other species of Tilletia are mostly based on symptom of infected plants、morphological characteristics of teliospores、 spontaneous fluorescence microscopy features、germination physiology and biochemistry of TCK. These methods not only waste time and energy but also dispute easily in the trade, so it is necessary to construction rapid and fast molecular methods of identification of TCK. Irradi-ation、pharmacy fumigation, thermal sterilization are TCK sterilisation process nowdays, irradiation were not widely used because it was influenced by the electron beam penetration ability. pharmacy fumigation has a certain impact on the environment, Studies have reported that teliospores of TCK under the conditions of dry heat sterilization at100℃for10min, the germination rate was not affected, and it is difficult to treat large amounts of wheat with these three methods. So look for an economic, convenient, environmentally-friendly methods to treat with TCK infected wheat has a significance to prevent spread of TCK.China has the appropriate climatic factor and susceptible host of TCK, once the fungi was introduced into China, it will bring huge economic losses. Our quarantine personnel have ofen acquired teliospores of TCK in import of wheat before. Host of TCK is widely, so it will most likely introduced into China with the other hosts. Thus, this article analysis the risk of hosts of TCK by FAO pest risk analysis criteria, after assessment, winter wheat was considered as very high risk level, barley was considered as high risk level, rye and grasses were consider-ed as medium risk level.The effects of different pretreatment, substrate and preservation time on the germination of teliospore of Tilletia contraversa was studied in this article. The results showed that the teliospores which were not sterilized, spreaded onto soil-extract agar and fresh obtained the highest germination percentage. Mycelium of T. contraversa originated from germinating was transferred to PSA、T-19、PDA medium. The result indicated that dwarf bunt fungus grew well on the T-19medium, some hyphae was monokaryon and others was dikaryon, mycelia which became dominated by a monokaryon if it was incubated at20℃, and stable dikaryons if incubated at16℃, but the capacity of the dikaryon hyphae of T. controversa to produce teliospores was gradually lost in subcultures of the parent colonies.General primer and Taqman Probe have been syntheticed according to the special sequences of TCK which have been published on articles. The results show that only DNA of TCK appeared specific band and amplification curve. TCK has been detected by using normal PCR and Real-time fluoreseent PCR. Wheat was inoculated with Tilletia contraversa to determine the effect of composting on teliospores survival. The germination rate of teliospore-s became lower and lower as the composting process, after ten days, teliospores lost germinat-ion ability completely. |
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