The Role of Resin Acids in the Relationship Between Scots Pine and the Sawfly, Diprion pini (Hymenoptera: Diprionidae). I.—Resin Acids in the Needles

Abstract

Throughout the northern hemisphere, there are many sawflies of the family Diprionidae which defoliate conifers and sometimes cause significant damage during their outbreaks. For example, in North America, the pine sawflies: Neodiprion swainei, Neodiprion rugifrons, Neodiprion dubiosus and Neodiprion lecontei are important pests on jack pine, Pinus banksiana. In Europe, Neodiprion sertifer. Microdiprion pallipes. and Diprion pini cause widespread damage to Scots pine, Pinus svlvestris. In France, Scots pine is usually preferred by D. pini, but when Scots pine is unavailable, this insect also feeds on the black pines, Pinus nigra ssp. laricio and austriaca. or on introduced species such as Pinus radiata and Pinus contorta.