Exobasidium vexans

Exobasidium vexans on tea leaves

Exobasidium vexans is a Brandpilzart from the family of Nacktbasidienverwandten ( Exobasidiaceae ). She lives as endoparasite on tea (Camellia sinensis). Symptoms of infestation by the fungus are red, strongly swollen leaf galls, which eventually burst. The species is found throughout Southeast Asia, where tea grows.

Features

Macroscopic characteristics

Exobasidium vexans is with the naked eye at first not to recognize. Initial symptoms of infestation are visible on the leaves: The leaves of infected tea plants form red spots, then more red bubbles. Later the chalk-white mycelium of the fungus breaks through and overgrown the bubbles that break out soon.

Microscopic characteristics

The mycelium of Exobasidium vexans grows and forms intercellular Saugfäden that grow in the storage tissues of the host. The four-to fünfsporigen, 30-35 × 5-6 microns large basidia are long, unseptiert and schmalkeulig. The elliptical spores are hyaline, 13-27 × 4.5-6.5 microns tall and thin-walled. First, they are unseptiert, ripe, they have a septum.

Dissemination

The Artareal of Exobasidum vexans coincides with the tea and covers large parts of Southeast Asia. In Africa, where also tea is grown, the species has not been found.

Ecology

Exobasidium vexans exclusively attacks young leaves of the tea plant. The fungus feeds on the present in storage tissues of the plant nutrients, its basidia later break through the stomata on the underside of leaves and put spurs free. The fungus is considered one of the most important diseases of tea and plantation economy and thus as a threat.

Swell

• C. Booth: Exobasidium vexans. In: CMI Descriptions of Pathogenic Fungi and Bacteria 779, 1983.

• Nacktbasidien
• Exobasidium
• Pflanzenmykose