DISPERSAL AND MATING IN THE FIELD BY MALE PINK BOLLWORM, PECTINOPHORA GOSSYPIELLA, LABELED WITH ³²P

Abstract

Radioactive phosphorus was fed to laboratory‐reared male pink bollworms, Pectinophora gossypiella (Saunders), for studies of dispersal and mating in the field. Released moths either irradiated with 20 Krad or unirradiated, were found predominantly within a few hundred meters of the release points. Prior to formation of a plant canopy, daytime‐resting places of moths were soil crevices at the bases of the plants. Later, when a protective plant canopy had formed, about half of the moths took resting places in the lower canopy, many in withered blooms. Little mating occurred between released males and native females, probably due to the great preponderance of native males in the test area. The technique of autoradiography of native females to determine mating with released labeled males was simple and effective. Zusammenfassung AUSBREITUNG UND PAARUNG IM FELD BEI MÄNNCHEN DES ROTEN BAUMWOLLKAPSELWURMS, PECTINOPHORA GOSSYPIELLA, NACH MARKIERUNG MIT32P Im Labor gezogene Männchen von P. gossypiella wurden mit 32P gefüttert, um Ausbreitung und Paarung im Baumwollfeld zu studieren. Freigelassene Falter, teils bestrahlt mit 20 Krad, teils unbestrahlt, wurden vorwiegend innerhalb von 100 m von der Freilassungsstelle gefunden. Vor Bildung eines geschlossenen Bestandes waren die Tagesruheplätze der Falter Bodenspalten an der Basis der Pflanzen. Später, wenn ein schützender, dichter Pflanzenbestand gebildet war, hatten die Falter ihre Ruheplätze etwa zur Hälfte in dem unteren Bereich des Pflanzenbestandes, davon viele in verwelkten Blüten. Zwischen freigelassenen Männchen und Freilandweibchen kam es nur zu wenig Paarungen, wahrscheinlich wegen des zahlenmässigen Übergewichts der Freilandmännchen im Gebiet. Die Technik der Autoradiographie von Freilandweibchen zur Erkennung einer Paarung mit freigelassenen, markierten Männchen war einfach und wirkungsvoll.

Behaviour of pink bollworm males near high‐dose, point sources of pheromone in field wind tunnels: insights into mechanisms of mating disruption

“…Moreover, during the day pink bollworm moths descend into crevices in the soil, sometimes settling at many centimetres below the soil's surface, where they remain until their normal time of sexual activity (Flint et al, 1975). Some males, particularly those sitting on the foliage, may be exposed continually to pheromone emanating from the disruptant formulation.…”

An alternative to conventional insect marking procedures: detection of a protein mark on pink bollworm by ELISA*

“…Studies to measure the dispersal characteristics of pink bollworm, Pectinophora gossypiella (Saunders) (Lepidoptera: Gelechiidae) frequently are conducted to determine dispersal patterns and behaviors (Flint et al, 1975;Van Steenwyk et al, 1978;Flint & Merkle, 1981;Bartlett, 1982;Raulston et al, 1996;Tabashnik et al, 1999). A wide variety of markers currently are available for marking pink bollworm and other lepidopterous pests prior to their release so that they can be distinguished from their native counterparts upon recapture (Hagler & Jackson, 2001).…”

Population structure and introduction history of the pink bollworm, Pectinophora gossypiella, in China

“…One explanation is that the limited active dispersal ability could generate population subdivisions in P. gossypiella . Many studies suggest that P. gossypiella adults typically remain within the current habitat (Flint et al., 1975; Wu et al., 2006), although some investigations have indicated that P. gossypiella can be caught at altitudes up to 1 000 m (McDonald & Loftin, 1935; Bariola et al., 1973). Another explanation is that transgenic cotton that produces toxins from Bacillus thuringiensis (Bt) have high levels of insecticidal efficacy against larvae of P. gossypiella and other lepidopteran pests (Flint & Park, 1999); thus, creating population bottlenecks in different regions of the world that could increase the rate of genetic divergence among these populations due to a founder effect and subsequent genetic drift.…”