Invasive Species Compendium

Detailed coverage of invasive species threatening livelihoods and the environment worldwide

Abstract

Evaluation of the daily rate of sex pheromone release by the females of two mealybug species (Homoptera Coccoidea Pseudococcidae).

Abstract

Since the females of many insect species show a daily rhythm of sex pheromone release that is influenced by light or temperature, and since males of Pseudococcus calceolariae (Mask.) showed 2 daily activity peaks that were thought to correspond with possible female peaks of pheromone release [see RAE/A 65, 6785], females of P. calceolariae and Planococcus citri (Risso) were tested in the laboratory in Portici, Italy, by using unmated conspecific males to evaluate their rate of pheromone release. Apparatus made of glass is described by which pheromone released by 1540 females of each species, kept in controlled environmental conditions, was collected every 2 h during a period of 24 h. The responses of males to the extracted fractions showed that virgin females of both species had no circadian rhythm of sexual activity but emitted the pheromone consistently and continuously throughout the day until mated.