Armillaria luteobubalina

Armillaria luteobubalina

Armillaria luteobubalina, commonly known as the Australian honey fungus, is a species of mushroom in the family Physalacriaceae. It is responsible for a disease known as Armillaria root rot, a primary cause of Eucalyptus tree death and forest dieback. Fruit bodies have cream- to tan-coloured caps that grow up to 10 cm in diameter.

About Armillaria luteobubalina in brief

Summary Armillaria luteobubalinaArmillaria luteobubalina, commonly known as the Australian honey fungus, is a species of mushroom in the family Physalacriaceae. It is responsible for a disease known as Armillaria root rot, a primary cause of Eucalyptus tree death and forest dieback. Fruit bodies have cream- to tan-coloured caps that grow up to 10 cm in diameter and stems that measure up to 20 cm long by 1. 5 cm thick. The fruit bodies, which appear at the base of infected trees and other woody plants in autumn, are edible, but require cooking to remove the bitter taste. The fungus is dispersed through spores produced on gills on the underside of the caps, and also by growing vegetatively through the root systems of host trees. The ability of the fungus to spread vegetatively is facilitated by an aerating system that allows it to efficiently diffuse oxygen through rhizomorphs—rootlike structures made of dense masses of hyphae. It may take years for infected trees to show signs of disease, leading to an underestimation of disease prevalence. Studies show that the spread of disease in eucalyptic forests is associated with infected stumps left following logging operations. Although several methods have been suggested to control the spread, they are largely economically or environmentally unfeasible. The distribution of A.  luteobUBalina suggests that it is an ancient species that originated before the separation of the precursor supercontinent Gondwana.

The species is in a lineage that includes A.montagnei and A.paulensis, both of which are sister to a lineage containing a single species in São Paulo, Brazil. A phylogenetic study of South American species concluded that A. Luteobubsalina is the most pathogenic and widespread of the six species found in Australia. It was first described in 1978 by mycologists Roy Watling and Glen Kile, who studied its effects on a fast-growing plantation ofEucalyPTus regnans near Traralgon, Victoria. It has also been collected in Argentina and Chile. The specific epithet is derived from the Latin lutea, which means yellow and yellow was chosen to highlight an important characteristic: strong yellow colour of the cap and lack reddish or brown tones in the typical stem of the other species in other regions of the world. A. luteobsalina was first discovered in 1978, after having been discovered several years earlier growing in a Eucallyptus plantation in southeastern Australia. A cluster of dead and dying trees discovered in 1973 suggested attack by a virulent primary pathogen, that is, one capable of infecting a host before invasion by other, secondary pathogens. The disease spread by the growth of underground mycelia in root systems, expanding outward from the initial infected stump at an average of 2.5 m per year. In Europe and North America in fact consisted of five and ten distinct “biological species”, respectively.