Impact of seed reducing natural enemies on weediness of thistles

A.W. Sheppard, CSIRO Division of Entomology, Co-operative Research Centre for Weed Management Systems, GPO Box 1700, Canberra, ACT 2601, Australia.


The impact of biological control agents introduced around the world to control thistles has resulted in some success with seed-reducing agents contributing to this process. This short paper reviews the knowledge on seed-losses to endophagous insects for Australian thistles in an attempt to suggest where such insects may have a role in future biological control programs. It also illustrates how, in addition to direct seed losses, natural enemies can affect the spread and long-term viability of seeds that escape destruction, thereby reducing regrowth potential of declining thistle infestations.


Plant Protection Quarterly (1996) 11 (Supplement 2) 243-245.