The objective of the project was to implement in France a classical biological program against the chestnut gall wasp, Dryocosmus kuriphilus (Dk), using releases of the exotic parasitoid Torymus sinensis. The expected outcome of this project were (i) the permanent establishment of the parasitoid and (ii) an efficient and long-term control of the pest.
A method is resented to reduce the severity of cankers caused by chestnut blight, Cryphonectria parasitica. This pathogenic fungus penetrates and necroses cortical tissues, which provoke mortality of adult trees aerial parts and failure of grafting.
In the 1970s, French researchers developed a biological control method using hypovirulent strains of the fungus. Since then, a research programme at INRA conducted with several organisations (Chambers of Agriculture, Union of Chestnut production Associations, the Forest Health Department) aims at clarifying and improving thecontrol methods.
The chestnut gall wasp in the Portuguese region of Terra Fria Transmontana: Three years of biological control
The Dryocosmus kuriphilus insect, chestnut gall wasp, introduced in Portugal in 2014, represents a serious threat to the national production of chestnuts. Over the years, various pest outbreaks have been identified, which is currently present in much of the Terra Fria Transmontana region, with levels of severe infestation levels. The official reports state, “We are currently witnessing a large and rapid dispersion of the insect and the alarm of the populations, given the damage it is already causing, so, an intensification of the parasitoid releases for these regions should be considered from 2020”.