Biology Reference
In-Depth Information
Iris Yellow Spot Tospovirus
Lettuce Big Vein Varicosavirus
On
Allium
sp. Including
A. cepa
.
Transmitted by a vector-fungus,
Olpidium
brassicae
. Vein clearing followed by enlarging
and bleaching.
Impatiens Latent Potexvirus
Lettuce Infectious Yellows
Closterovirus
Symptomless virus transmitted only by mechan-
ical inoculation.
Virus infected lettuce, sugarbeets, cantaloupe,
watermelons, melons, squash, and carrots. Main
symptoms included chlorosis,
Impatiens Necrotic Spot Tospovirus
reddening and
Previously called strain of Tomato Spotted Wilt
Tospovirus. It is the most common and most
damaging virus in the greenhouse industry. The
virus has an extremely broad host range and its
vector, the western flower thrips,
Frankliniella
occidentalis
, are widespread and difficult to con-
trol. Symptoms caused by virus were variable but
generally occurred as brown or black necrotic
spots, blotch, necrotic rings on leaves and flower
distortion. Often the center leaves collapse.
Infected plants are stunted and die prematurely.
The control of vector is essential in greenhouses.
brittle leaves; plants stunted.
Lettuce Speckles Mottle Umbravirus
Virus in mixed infection is encapsidated in coat
protein of Beet Western Yellows Luteovirus.
Lettuce Mosaic Potyvirus
Widespread on lettuce. Leaves mottled, deformed,
yellowed, browned; plants stunted or dead. Trans-
mission is by peach and root aphids and in seed.
Control vectors, use virus-free seed;
Ixia Mosaic
rogue
seedbeds.
Perhaps iris mosaic.
Lilac Mottle Carlavirus
Johnsongrass Mosaic Potyvirus
Caused leaf chlorosis and mottling on
Syringa
spp.
Known also as Maize Dwarf Mosaic Virus strains
0 and Kansas and as Sugarcane Mosaic Virus. On
Johnsongrass virus caused systemic mosaics.
Lilac Ring Spot Carlavirus
Kalanchoe Top-Spotting Badnavirus
Pale green to yellow spots, lines, broad diffuse
rings, and bands on lilac leaves, often with dis-
tortion and holes in tissue.
Kalanchoe blosfeldiana
plants showed sunken
yellow spots and sometimes leaf deformation.
Lilac Witches' Broom Phytoplasma
Laburnum Mosaic
On lilac, privet in Maryland. Brooming symp-
toms; lateral buds produce two to six slender
shoots, which branch freely, with very small
Infectious variegation. Bright mottling of foliage,
often with veins picked out in yellow.
