|Smith, Lincoln - Link|
Submitted to: Biological Control
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 11/8/2005
Publication Date: 1/21/2006
Citation: Smith, L., Hayat, R., Christofaro, M., Tronci, C., Tozlu, G., Lecce, F. 2006. Assessment of risk of attack to safflower by ceratapion basicorne, a prospective biological control agent of yellow starthistle. Biological Control. 36(3):337-344. Interpretive Summary: Yellow starthistle is an alien weed that has invaded about 20 million acres in the western U.S. It is especially abundant in Pacific western states. The spiny plant interferes with grazing livestock and outdoors recreation, it is fatally poisonous to horses, and it outcompetes desirable vegetation. Six species of insects have been introduced as biological control agents, but they are not providing sufficient control. Foreign exploration in the Mediterranean Basin indicates that the weevil, Ceratapion basicorne, could be an important biological control agent. Previous laboratory experiments showed that the insect can sometimes develop on safflower. We conducted field studies in eastern Turkey, where the insect is native, to determine if this insect poses a risk to safflower
Technical Abstract: Ceratapion basicorne (Coleoptera: Apionidae) is a prospective biological control agent of yellow starthistle (Centaurea solstitialis, Asteraceae: Cardueae), which is an important invasive alien weed in the western United States. Previous studies have shown that it is possible for this insect to oviposit on and complete development on safflower (Carthamus tinctorius). Field experiments were conducted at 3 sites in eastern Turkey during 3 years to evaluate the risk of attack on safflower by this insect in its native range. At two sites where C. basicorne was the only apionid observed, no safflower plants were attacked despite high attack rates on yellow starthistle (48 to 98% of plants infested). At a third site, where C. basicorne, C. scalptum and C. orientale were present, 8 to 34% of safflower plants were infested, but none of the identifiable insects reared from safflower during 3 years were C. basicorne. Other authors have reported rearing C. basicorne only from Ce. solstitialis, Ce. cyanus, Ce. depressa, and Ce. [=Cnicus] benedictus. Our results indicate that C. basicorne does not attack safflower under field conditions and that its introduction would not pose a risk to this crop.