If you are experiencing problems downloading PDF or HTML fulltext, our helpdesk recommend clearing your browser cache and trying again. If you need help in clearing your cache, please click here . Still need help? Email email@example.com
Effeeticeness of a nuclear polyhedrosis virus and Bacil- Ius thuringiensis Berliner for control of the corn ear- worm, Heliothis zea (Boddie), was investigated on successive sweet corn plantings in southern California in 1965, 1966 and 1967. Effeetiveess of the treatments was determined by using the classification "marketable ears" (less than 25% of the car from the tip injured by larval feeding) as delined in the Agricultural Code of California in the sections pertaining to marketing stan- dards for green corn. In 1965 , 4 applications of a 2.5 larval unit (LU) virus dust formulation at 3-day inter- vals, using the individual-ear. brush-dust method, resulted in an average of 35.8% increase in marketable ears and 42% ears free of larval injury. The virus dust was more effective than a Blacillus dust or a combination of the, two when applied to the silk. In 1966. 4 applications of a virus spray to the silk at 3-day intervals at the rate of 228 LU per acre resulted in a significant increase (27%) in marketable ears and a lower number of live larvae present at harvest. Virus sprays applied to the tassels were ineffective in reducing the larval population thereon, and a tassel + silk treatment was not significant. ly better than a silk treatment alone for control of the larvae affecting the cars. The 228 LU virus Tate per acre was consistently better than 114 LU per acre. Similar applications of a virus spray at 194 LU per acre in 1967 resulted in a significant increase (24%) in marketable cars and a lower number of live larvae at harvest. Ef- fectiveness of the virus treatment was not increased sig- nificantly by the addition of mineral oil, emulsifier, or wetting agent. From 36 to 70.6% of the larvae, collected from cars in the control plots and reared individually in the laboratory, were killed by virus transmitted by ovipositing adults, moving from treated to untreated silk. During the 3-year study, 77 to 87% marketable ears were obtained with virus sprays and 91 to 100% with virus dust applications.
Document Type: Research Article
Publication date: April 1, 1970
More about this publication?
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.