Abstract
dc:description.abstractTobacco mosaic virus (TMV) infects all classes of tobacco (Nicotiana tabacum L.) and causes losses worldwide. The N gene is the most effective means of controlling TMV; however, this gene is associated with reduced yield and quality in flue-cured tobacco. The mode of inheritance of TMV resistance was determined in two tobacco introductions (TI) from N. tabacum germplasm, both of which produced a hypersensitive response when inoculated with TMV. Inheritance studies with TI 1504 and TI 1473 indicate that a single dominant gene controls resistance. The gene governing resistance in TI 1504 is allelic to the N gene in NC 567. The gene providing resistance in TI 1473 is not allelic to the N gene, providing a potentially new source of resistance. Currently, plant breeders must rely on the N gene. The N gene is used in the heterozygous state to help overcome poor agronomic effects associated with homozygous resistance; however, systemic movement of TMV is occasionally seen in resistant plants. A TMV susceptible inbred (K 326), a resistant inbred (NC 567), and three resistant hybrids (NC 297, RGH4, and Speight H2O) were inoculated with TMV at transplanting, layby, and topping using different inoculation methods. Plant parts were tested for viral presence and biological activity. Viral movement into all plant parts was observed in K 326. No systemic movement was evident in the plant parts of NC 567, while virus did move into the corollas, pistils, late season sucker growth, and roots of the resistant hybrids showing systemic necrosis.
Degree
thesis:*- Name thesis:degree_name
- Master of Science
- Level thesis:degree_level
- masters
- Discipline thesis:degree_discipline
- Crop and Soil Environmental Sciences
- Department dc:contributor.department
- Crop and Soil Environmental Sciences
- Grantor dc:publisher
- Virginia Tech
- Year dc:date.issued
- 2001
Author and committee
dc:creator, dc:contributor.*- Author dc:creator
-
- Bagley, Christopher A.
- Chair dc:contributor.committeechair
-
- Wilkinson, Carol A.
- Committee members dc:contributor.committeemember
-
- Buss, Glenn R.
- Tolin, Sue A.
- Johnson, Charles S.
Subjects
dc:subject × 3Rights
dc:rights- Statement dc:rights
-
- In Copyright
- Licence dc:rights.uri
Identifiers
dc:identifier.*- Dc Identifier Other
- etd-01122002-113631
- OAI identifier oai:identifier
- oai:vtechworks.lib.vt.edu:10919/30911