<i>Eutypa armeniacae</i> Hansf. &amp; Carter, sp. nov., an airborne vascular pathogen of <i>Prunus armeniaca</i> L. in southern Australia

Abstract

A newly described Ascomycete, Eutypa armeniacae Hansf. &amp; Carter, is shown to give the symptoms associated with "gummosis" disease of Prunus armeniaca L. (common apricot) in southern Australia. Experimental evidence is produced to substantiate the hypothesis that E. armeniacae is the ascigerous stage of an imperfect Cytosporina sp, which has long been recognized as the causal organism of "gummosis", and that airborne ascospores of E. armeniacae are the only source of inoculum. Ascospores of this species are shown to be well suited to aerial dissemination over long distances.