FIELD CAGE PERFORMANCE OF 2 TACHINID PARASITOIDS OF THE TOMATO FRUITWORM ON INSECT RESISTANT AND SUSCEPTIBLE TOMATO LINES

Rates of parasitism of Helicoverpa (= Heliothis) zea (Boddie) (Lepidop tera: Noctuidae) by two tachinid parasitoid species differing in larvi position habits were measured in field cages on tomato plant lines wit h or without methyl-ketone (2-tridecanone and 2-undecanone)-mediated i nsect resistance. Hosts were placed on resistant or susceptible plants , exposed to parasitoids for 24-48 b, then held on artificial diet for parasitoid emergence. Rates of parasitism by Archytas marmoratus (Tow nsend) (Diptera: Tachinidae), which larviposits on its host's food pla nt, were significantly reduced on the resistant plants, relative to th ose on the susceptible plants. Parasitism by another Tachinid, Eucelat oria bryani Sabrosky, which larviposits directly into its host and doe s not directly contact the foliage of its hosts, food plant as a small larva, was not affected by the methyl-ketone mediated resistance.