Isthmiella faullii. [Descriptions of Fungi and Bacteria].
Abstract A description is provided for Isthmiella faullii. Information is included on the disease caused by the organism, its transmission, geographical distribution, and hosts. HOSTS: Apparently confined to Abies balsamea. DISEASE: Causes a needle blight of Abies balsamea. According to Darker (1932), it 'is the commonest and most destructive of the Hypodermataceae on Abies balsamea in eastern North America'. It is particularly damaging to seedlings and juvenile plants. In northern Ontario, from where the disease was originally identified, infection occurs during the summer, but signs of the disease do not appear until the following spring, when needles become brown and conidiomata develop, conidia being discharged in July, and shortly after this ascomata begin to form, maturing in July of the following year. GEOGRAPHICAL DISTRIBUTION: Reported from Canada: Nova Scotia, Ontario, Quebec and USA: Michigan and New Hampshire. TRANSMISSION: Through air dispersal of ascospores, which directly infect the leaves (Darker, 1932).