POLLEN AS A MARKER FOR MIGRATION OF HELICOVERPA-ARMIGERA AND HELIOTHIS-PUNCTIGERA (LEPIDOPTERA, NOCTUIDAE) FROM WESTERN QUEENSLAND

Pollen carried on the probosces of Helicoverpa punctigera (Wallengren) and H. armigera (Hubner) trapped in western Queensland and in croppin g areas of eastern Australia in September 1989 and 1990 was identified by scanning electron microscopy. Ninety-five per cent of moths carrie d pollen. A total of 19 'morphological pollen species', representing 1 4 plant families, was found. Up to six pollen species were found on in dividual moths, and 61% carried more than one. Pollen from plants unsu itable for larval survival was common. Pollen loads generally reflecte d the abundance of locally flowering plants, but there were exceptions which suggested migration. Pollen of Ptilotus (Amaranthaceae), Vellei a (Goodeniaceae) and Eremophila (Myoporaceae), and the Asteraceae (Tub uliflorae) were found on moths trapped in the east. These plants eithe r did not occur in the areas where the moths were caught, or did not f lower there at the time the moths were caught. However, they were abun dant in possible source areas such as western Queensland. Among moths caught in eastern regions, 30% of H. punctigera and 18% of H. armigera carried pollen from such plants. The value and limitations of moth-bo rne pollen as a marker for migration are discussed.