Record Details
Some cytological aspects of streak mottle virus in Lilium speciosum Thunberg
ScholarsArchive at Oregon State University
| Field | Value |
|---|---|
| Title | Some cytological aspects of streak mottle virus in Lilium speciosum Thunberg |
| Names |
Elser, John Elmore
(creator) Allen, T. C. (advisor) |
| Date Issued | 1968-05-10 (iso8601) |
| Note | Graduation date: 1968 |
| Abstract | Cultivated lilies include many garden varieties in addition to the Easter lily, Lilium longiflorum Thunb. A popular member of the garden group is Lilium speciosum Thunb., whose leaves can be discolored by a virus symptom described as streak mottle. This disorder is characterized by dashes of chlorotic tissue interspersed with green. In order to gain further insight about the nature of the virus inciting streak mottle on L. speciosum, leaf pieces of approximately 0.5 mm square were immersed in buffered glutaraldehyde fixative, treated with osmium tetroxide, dehydrated, and embedded in epoxy resin. After thin sectioning and staining, the specimens were examined with an electron microscope. Configurations described as pinwheels and bundles, characteristic of 750 mμ flexuous rod viruses, were seen in abundance within leaf mesophyll cells, epidermal cells, and to a lesser extent, in xylem cells. In agreement with previous workers, the pinwheel and bundle inclusions were found to be different views of the same body. This intracellular body associated with streak mottle can be described as a cylindrical inclusion with curved plates emanating from a central hollow core. While some viruses appear to occur along the inner curvature of the plates, at least one has been reported as separate from the pinwheel-bundle figure. It appears that streak mottle virus is also one of the latter. L. speciosum mesophyll cells were found to contain crystals, and these were observed in both diseased and healthy tissue. Diseased tissue displayed an additional crystalline body, which occurred in clusters and was often seen in close proximity to pinwheel-bundle figures. These bodies seem to be homologous to those found within nuclei of tobacco leaf mesophyll cells infected with tobacco etch virus, also a flexuous 750 mμ rod. The chloroplasts of both infected and healthy mesophyll cells showed large vacuoles of unknown significance. A smaller peripheral vesicle that occurs between the two layered plastid-limiting membrane seemed to occur more frequently in diseased cells than in healthy. Depletion of a chloroplast substance is suggested by the presence of these vesicles. The remainder of the organelles, namely, dictyosomes, nuclei, and mitochondria, appeared to be similar in both healthy and diseased cells. On the basis of preliminary findings further work may establish that streak mottle virus induces premature degeneration of host cells. |
| Genre | Thesis/Dissertation |
| Topic | Lilies |
| Identifier | http://hdl.handle.net/1957/47004 |
