Peppermint, Mentha piperita 'Black Mitcham' was established as a host for tomato
spotted wilt virus-impatiens serotype (TSWV-I). TSWV-I infection of peppermint,
initially observed in a research greenhouse (Corvallis, OR), included stunting and
downward curling of leaves accompanied by bronzing, and occasionally tip necrosis.
Young leaves appeared either symptomless, deformed, or pale even under high nitrogen
conditions. Older leaves had sunken, brownish-grey lesions. Bright yellow mottling was
observed on newly mature deep green leaves. A begonia isolate of TSWV-I was
transmitted to peppermint both mechanically and by western flower thrips, Frankliniella
occidentalis (Pergande). Symptoms of TSWV-I infection were similar although only a
faint yellow mottling was produced and only under cool temperatures (15°C). ELISA
detection of virus distribution throughout the plant indicated infection was systemic.
Bulked groups of thrips (5 thrips/sample) also tested positive for TSWV-I using ELISA.
Transmission efficiency of 4, 6, 8, and 10 day old thrips adults given acquisition sources
during the entire nymphal stage varied from 0-40% for thrips tested in pairs and 0-20%
for single thrips (based on a 12 hour access feeding period). Adults 2 days old failed to
transmit the virus. Western flower thrips exposed to TSWV-I had reduced survival and
reproductive potential and slower development rates than unexposed thrips. Virusexposed
thrips were 1.4 times as likely to die than unexposed thrips on a given day. Both
individual and population reproductive potentials were significantly lower. Preoviposition
period was extended in virus-exposed thrips. Development time from second instar to
adult was 15% longer for virus-exposed thrips. This is the first report of altered
population parameters in western flower thrips exposed to TSWV-I. / Graduation date: 1992
| Identifer | oai:union.ndltd.org:ORGSU/oai:ir.library.oregonstate.edu:1957/36670 |
| Date | 10 September 1991 |
| Creators | Sether, Diane M. |
| Contributors | DeAngelis, Jack, Rossignol, Phil |
| Source Sets | Oregon State University |
| Language | en_US |
| Detected Language | English |
| Type | Thesis/Dissertation |
Page generated in 0.0022 seconds