Axenic culture of Puccinia species collected in Canada

Abstract

Twenty-eight of 29 cultures of Puccinia graminis tritici, 2 of P. graminis avenae. 1 of P. graminis secalis, 2 of P. coronata avenue, and 2 of P. recondita that originated in Canada grew on peptone medium. Three of the 36 strains investigated grew when subcultured. One grew for three subculturings, another grew for 1 year when subcultured at 2- to 4-week intervals, and a third ‘vegetative’ culture has produced fluffy, white mycelial colonies through numerous subculturings over 2½ years. The ‘vegetative’ culture was pathogenic at first but later appeared to become nonpathogenic. Uredial cultures established from it varied in urediospore color and virulence. Electron microscope studies showed that the culture is dikaryotic and apparently haploid.