Susceptibility of sunflower to Ophraella communa LeSage (Coleoptera: Chrysomelidae), a candidate for the biological control of common ragweed (Ambrosia artemisiifolia L.).

摘要

The suitability of sunflower (Heliantus annuus L.) as a host of Ophraella communa Le Sage (Coleoptera: Chrysomelidae) was evaluated under greenhouse and field conditions. Population dynamics of O. communa on sunflower and on ragweed (Ambrosia artemisiifolia L.) were determined using a life table approach. Sixty percent of O. communa females died during the first 30 days on sunflower while only 14% died on ragweed plants. Only 20% of fertile females laid eggs on sunflower plants as compared with 100% on ragweed plants. Fecundity, life duration, egg viability, and other biological parameters were significantly higher on ragweed plants than on sunflower plants. Ragweed is the main host plant for O. communa. Nevertheless, in specific situations (no-choice) adults and larvae of O. communa can damage sunflower plants. However, O. communa cannot complete its life cycle or increase its population on sunflower plants.