Title: Ovigeny in Selected Generalist Predators Authors
|Legaspi, Benjamin -|
Submitted to: Meeting Abstract
Publication Type: Proceedings
Publication Acceptance Date: April 30, 2009
Publication Date: June 10, 2009
Citation: Legaspi, J.C., Legaspi, B. 2009. OVIGENY IN SELECTED GENERALIST PREDATORS. 3rd International Symposium on Biological Control of Arthropods. Meeting Abstract. Technical Abstract: “Ovigeny” refers to the process of egg production in adult insects. “Pro-ovigenic” adult insects emerge with a fixed complement of mature eggs; whereas, “synovigenic” species continuously produce and develop eggs throughout adulthood. Very little work has been done on ovigeny in insect predators. We studied four predators such as Podisus maculiventris (Heteroptera: Pentatomidae), Orius insidiosus (Hemiptera: Anthocoridae), Delphastus catalinae (Coleoptera: Coccinellidae), and Geocoris punctipes (Heteroptera: Lygaeidae). We examined egg load at regular intervals (dependent on lifespan). Numbers of eggs laid were also recorded. In P. maculiventris, numbers of immature eggs increased with predator age whereas numbers of mature eggs declined providing clear indication of continuous egg production. Similar results were found in G. punctipes. In other predators, egg loads tended to increase with time, except in D. catalinae. However, numbers of eggs laid all increased with time. These findings suggest that egg production occurs during the adult stage in all these predators and that all predators studied were synovigenic to varying degrees.