Polymorphism in warning coloration is puzzling because positive frequency-dependent selection by predators is expected to promote monomorphic warning signals in defended prey. We studied predation on the warning-coloured wood tiger moth (Parasemia plantaginis) by using artificial prey resembling white and yellow male colour morphs in five separate populations with different naturally occurring ...

Powdery mildew-infected rainforest spinach (Elatostema reticulatum) plants were found in Queensland, Australia. Based on morphology and nrDNA ITS sequence analyses, the pathogen was identified as Podosphaera xanthii, a powdery mildew species with worldwide distribution broad host range. This is first record of P. xanthii infecting E. reticulatum, infection recorded for this native Australian pl...

The major cause of powdery mildew in melons (Cucumis melo L.) is the fungus Sphaerotheca fuliginea. There are several cultivar- and season-specific races of this fungus. In order to control powdery mildew, it is important to introduce resistance to fungal infection into new cultivars during melon breeding. Haploid breeding is a powerful tool for the production of pure lines. In this study, it w...

Verticillium lecanii has been found growing in pustu'les of the uredial stage of a number of rust fungi (GAMS 1971, SCHROEDER and HAssEBRAuK 1957, CASPER and MENDGEN 1979, SPENCER 1'980), and in some insects (HALL 1980). SCHROEDER and HASSEBRi\UK (1957) observed that this fungus is able to penetrate the urediospores of Puccinia striiformis. It remains to be shown, however, whether Verticillium ...