Aphid-Transmitted Potyvirus
Found in many Asian countries
Symptoms
Leaf mottle and dark green vein-banding are the most
characteristic symptoms. Leaves of some cultivars are
smaller and distorted. Symptoms are most obvious on
the younger, smaller leaves.
Plants infected when young become stunted and
have dark-green streaks on their stems and branches.
Most of their flowers drop before fruit formation. A few
mottled, distorted fruit may be produced. Such
symptoms contribute to significant yield losses.
Conditions for Disease Development
Chilli veinal mottle virus (ChiVMV) is transmitted by
several species of aphids: green peach aphid, Myzus
persicae; cotton melon aphid, Aphis gossypii; cowpea
aphid, Aphis craccivora; green citrus or spirea aphid,
Aphis spiraecola; corn leaf aphid, Rhopalosiphum
maidis; citrus brown aphid, Toxoptera citrida; and rusty
plum aphid, Hysteroneura setariae.
An aphid gets the virus by feeding on an infected
plant for only a few seconds. The aphid can then transmit
the virus immediately the next time it bites into a plant,
then losing the virus. The virus is generally retained by
the aphid for no more than one hour. Winged aphids of
the above species are the most likely to spread the
virus to other pepper plants and are the most difficult to
control. The virus is also transmitted mechanically and
by grafting, but not by seed.
Control
Resistant/tolerant plant material is available from
– The World Vegetable Center, Taiwan.
Grow transplants in a nethouse or cover seedbeds
with a 32-mesh or finer mesh net to prevent introduction
of aphids. Use yellow sticky traps to monitor and to
reduce aphid populations.
Avoid touching or handling pepper plants prior to
setting them in the field. Remove any diseased
seedlings that show symptoms of the disease and place
them in a refuse pile away from pepper production fields.
1 comment:
Very helpful presentation for the identification and management of this virus by the field workers and extension agents. Effort is highly appreciated.
Vinod shrei
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