Attract-and-kill: a new strategy for the management of the potato tuber moths Phthorimaea operculella (Zeller) and Symmetrischema tangolias (Gyen) in potato: laboratory experiments towards optimising pheromone and insecticide concentration.
BACKGROUND
Sex pheromones of the potato tuber moths Phthorimaea operculella (Zeller) and Symmetrischema tangolias (Gyen) are ideal tools to monitor pest flight activity but are not used as means of control. The aim of the present study was to test the suitability of an attract-and-kill strategy consisting of pure pheromones and the contact insecticide cyfluthrin as the active ingredient, formulated with plant oils and ultraviolet absorbers, and applied in droplet sizes of 100 microL.


RESULTS
Cyfluthrin at a concentration of 5 g L(-1) resulted in the highest and fastest killing of males after 48 h, with a 100% mortality after 3-4 days. In contrast, control males survived for 13 days. In olfactometer experiments, the pheromone concentration of 0.5 g L(-1) was significantly most attractive against eight virgin females. At controlled conditions (20 degrees C), no reduction in efficacy of the attract-and-kill formulation was observed for a minimum period of 36 days, whereas under natural environmental conditions the efficacy reduced gradually after day 6 of exposure. The longer the droplet was exposed, the longer was the time to reach 100% mortality of males.


CONCLUSIONS
Compared with attract-and-kill studies for other pest species, the results are promising as a means of achieving highly effective control of potato tuber moths under field conditions.
Kroschel
Jürgen
J
International Potato Center (CIP), Apartado 1558, Lima 12, Peru. j.kroschel@cgiar.org
Zegarra
Octavio
O
D000818:Animals; D001681:Biological Assay; D002626:Chemistry, Pharmaceutical; D004355:Drug Stability; D005260:Female; D007300:Insect Control / Q000379:methods*; D007306:Insecticides / Q000008:administration & dosage / Q000737:chemistry; D007753:Laboratories; D008297:Male; D009036:Moths / Q000187:drug effects*; D009570:Nitriles / Q000737:chemistry; D035281:Plant Tubers; D011722:Pyrethrins / Q000737:chemistry; D012724:Sex Attractants / Q000008:administration & dosage / Q000737:chemistry / Q000494:pharmacology*; D011198:Solanum tuberosum
D007306:Insecticides; D009570:Nitriles; D011722:Pyrethrins; D012724:Sex Attractants; C052570:cyfluthrin