Responses and host specificity of Phrydiuchus sp. and P. topiarius (Germar) were studied to determine the suitability of these weevils for use in biological control of Salvia aethiopis L., an introduced biennial range weed of Western North America. Phrydiuchus weevils are recorded only from biennial or perennial Salvia species, characterized by having basal leaf rosettes. Adult feeding and ovipositional activity are synchronized with vegetative growth phases of the host plant. In the laboratory weevils fed and oviposited regularly on plants and bouquets of S. aethiopis, S. argentea L., S. sclarea L., S. verbenacea L., and bouquets of Melissa officinalis L., and Lycopus europaeus L. The weevils fed to a degree on other plants but did not oviposit normally because these plants lack some nutritive elements necessary for oocyte development and ovipositional stimuli. In nature the weevils appear to search at random for their host, concentrating and feeding on the basal Salvia leaves in response to chemical stimuli. They prefer basal leaves for oviposition and feeding. Larval development occurred only on Salvia rosettes; stems of these plants and stems and rosettes of other plants are unsuited for tunneling and probably for food.
Document Type: Research Article
Publication date: February 1, 1966
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Journal of Economic Entomology is published bimonthly in February, April, June, August, October, and December. The journal publishes articles on the economic significance of insects and is divided into the following sections: apiculture & social insects; arthropods in relation to plant disease; forum; insecticide resistance and resistance management; ecotoxicology; biological and microbial control; ecology and behavior; sampling and biostatistics; household and structural insects; medical entomology; molecular entomology; veterinary entomology; forest entomology; horticultural entomology; field and forage crops, and small grains; stored-product; commodity treatment and quarantine entomology; and plant resistance. In addition to research papers, Journal of Economic Entomology publishes Letters to the Editor, interpretive articles in a Forum section, Short Communications, Rapid Communications, and Book Reviews.