Development of a formulation and application technique of hypovirulent Cryphonectria parasitica - strains usable in practice for biological control of chestnut blight in Austria

摘要

More than ten years chestnut blight is threatening the native chestnut tree in Austria Castanea sativa. Entire stands in otherwise dense deciduous woods of Southern Styria and Burgenland have died because of this disease. In the framework of these studies a formulation - the "Pilzkleister" (= fungal goo) - has been developed. Fungal mycelia of hypovirulent strains of Cryphonectria parasitica are embedded in a starch-based matrix and are simple usable for treatments of chestnut blight. The "Pilzkleister" is using the principle of transmissible hypovirulence of C. parasitica for causing healing reactions. Highly successful direct treatments of necroses get possible with the "Pilzkleister". The direct treatment with hypovirulent fungal strains of Cryphonectria parasitica makes artificial dissemination of hypovirulence in Austria possible at the same time. Natural occurrence of hypovirulence has not been observed in Austrial until now. The "Pilzkleister" is storable for one year and well-applicable in practice.