Symptoms

Red clover vein mosaic virus (RCVMV) generally causes vein mosaic, mosaic streaking and stunting in various legumes. RCVMV causes a characteristic chlorosis of leaf veins, veinlets and tissue, and reduces its yield by reducing the foliage growth, decreasing persistance and increasing susceptibility to root rots.
The first report of RCVMV in pulses was of a disease called Wisconsin pea stunt which was characterised by severe plant stunting, tight apical resetting, leaves of reduced size, often wrinkled and folded upward showing marked vein clearing. In most pea cultivars, the first symptoms of systemic infection were usually systemic vein clearing and lead curling although some cultivars developed necrotic stem streaking sometimes followed by irregular yellowing and premature plant death.

Organism

Carlavirus flexiviridae

Host range

Pulses and lucerne.

Method of spread

The virus is spread non-persistently by a range of aphids (Acyrthosiphon pisum, Cavariella aegopodii, Myzus persicae and Therioaphis maculata). Seed transmission is also possible (but not common) in red clover, peas and faba bean. Mechanical transmission has also been reported.

Aphid vectors currently in Australia

Acyrthosiphon pisum = pea aphid
Cavariella aegopodii = Carrot willow aphid
Myzus persicae = Green peach aphid
Therioaphis maculata = Spotted alfalfa aphid

Confused with?

Other viruses and plant nutritional deficiencies.

Where?

Europe, India, South Africa and USA.