Moth, sunflower

The banded sunflower moth (Cochylis hospes Wlshm. also cited as Phalonia hospes Wlshm. (Schulz, 1978)) is a relatively minor pest of sunflower that attacks the flower heads and causes seed destruction. However, damage has increased in North Dakota in recent years (Charlet et al., 1995). While the insect is also found on Jerusalem artichoke (Beregovoy and Riemann, 1987), its activity is of no economic consequence. The banded sunflower moth is found from the East Coast of the U.S. to the Dakotas, and south into Kansas, Arkansas, and Texas, as well as in Saskatchewan and Manitoba in Canada (Westdal, 1949). 

The sunflower moth (Homoeosoma electellum Hulst) is a serious pest of sunflower and has been reported on Jerusalem artichoke (Satterthwait and Swain, 1946). The damage, however, is almost exclusively to the seed head and, as a consequence, of no importance to Jerusalem artichoke production. 

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Varieties of sunflower (Helianthus annums, Asteraceae) that are resistant to attack by larvae of the sunflower moth (Homeosoma electellum) contain high concentrations of trachyloban-19-oic acid and (-)-16-kauren-19-oic acid in their florets (84,132). 

Banded sunflower moth [Lepidoptera Tortricidae] Cochylis hospes Walsingham... 

Sunflower moth [Lepidoptera Pyrlidae] Homoeosoma electellum Hulst... 

Beregovoy, V.H. and Riemann, J.G., Infestation phenology of sunflowers by the banded sunflower moth, Cochylis hospes (Cochylidae Lepidoptera) in the North Plains, J. Kan. Entomol. Soc., 60, 517-527, 1987. 

Charlet, L.D., Glogoza, P.A., and Brewer, G.J., Banded sunflower moth, N.D. State Univ. Coop. Ext. Serv. Bull., E-832, 1995. 

In this chapter, we first review the terpenoid constituents isolated from resistant wild species of Helianthus and present the results of some insect bioassays with these compounds. Then we discuss the evidence which implicates terpenoids in the resistance to the sunflower moth (Homoeosoma electellum), the most destructive insect pest of cultivated sunflower in the United States (4), and describe how this information might be exploited in reducing insect damage to cultivated sunflower. 

Homoeosoma electellum (Lepidoptera Pyralidae) - the sunflower moth. In contrast to L eridania and II. sanguinipes, H. electellum is a specialist which feeds on the inflorescences of a few species of the Asteraceae (4,. 51). Since sesquiterpene lactones are found in several parts of the infloresences of Helianthus species which are considered to be resistant to the sunflower moth (52). it was thought that these compounds might serve to limit the damage caused by this insect. 

Possible role of sesquiterpene lactones in resistance to the sunflower moth. 

Banded sunflower moth Asana XL, Baythroid, Furadan 4F, Lorsban 4E, Scout X-TRA, Warrior... 

Despite the usual antifeedant or toxic effects observed with other insects, larvae of the sunflower moth Homoesoma electellum, Lepidoptera Pyralidae), a specialist on species of sunflower (Helianthus), are able to feed on flower parts that contain appreciable amounts of sesquiterpene lactones (Gershenzon and Croteau, 1991). 

Varieties of sunflower (Helianthus annms, Asteraceae) that are resistant to attack by larvae of the sunflower moth... 

Homeosoma electellum) contain high concentrations of tra-chyloban-19-oic acid (70) and ( —)-16-kauren-19-oic acid (71) in their florets. As sunflower florets that contain only small amounts of these compounds are a major portion of the diet of first instar larvae of this insect, it is likely that these acids serve as feeding inhibitors. At the 1% level, both kaurenoic and trachylobanoic acids decreased the growth of sunflower moth larvae and tobacco budworm (Heliothis virescens) by about 50%. At the 0.5% level, both reduced larval growth of the cotton bollworm and the pink bollworm to less than 5% (Fig. 22.23) (Mabry and Gill, 1979). The Z-and -isomers of (- )-ozic acid (72) have been isolated from Helianthus occidentalis and may be associated with resistance to insect attack (Stipanovic et al., 1979). 

Waiss, A.C., B.G. Chan, C.A. Elliger, V.H. Garrett, E.C. Carlson, and B. Beard Larvicidal factors contributing to host-plant resistance against sunflower moth. Naturwissenschaften 64, 341 (1977). 

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