Invasive Species Compendium

Detailed coverage of invasive species threatening livelihoods and the environment worldwide

Abstract

The life history of the Texas root rot fungus, Ozonium omnivorum Shear.

Abstract

The author has found what he believes to be the perfect stage of Phymatotrlchum (Ozonium) omnivorum, the cause of the Texas root rot of cotton [see this Review, iii, p. 134].
In a cotton field near Paris (Tex.), where the crop had suffered severe losses from attacks of P. omnivoro in, a shoot of the osage orange (Maclura aurantiaca) growing in the vicinity showed the characteristic symptoms of the wilt produced by Osonium. On examination, the typical mycelial strands of this fungus were observed extending up the lower part of the stem, but at a height of several inches above soil level they changed into a subiculum which surrounded the stem and formed a hymenium with the typical spines of a Hydnum. Attempts to grow the Ozonimn stage from the Hydnum failed. It is pointed out that conidial forms similar to Phymatotrichum are known in the Hymenomycetes, and the sterile mycelium is somewhat like Persoon's genus Fibrillaria which includes some hymenomycetous mycelia.
The fungus is named H. omnivorum n. sp. and an English diagnosis is given.