Cultivated potato is an autotetraploid (2n=4x=48), i.e., it has four complete sets of chromosomes. Tetraploids can harbor considerable heterozygosity (Jacobs, 1985) since there are potentially four possible alleles per locus. Reducing the ploidy level of potato from the tetraploid to the dihaploid level (2n=2x=24) and then the monoploid (2n=1x-12), or reducing diploid potato spp. to the monoploid level is a way of developing pure homozygous lines by doubling the monoploid genome.
Homozygous breeding lines are important since potato is a highly cross pollinated crop and inbreds are absent. The reduction of the ploidy level can be realised through anther and microspore culture. This method bears a great deal of significance in that it provides a selection against lethal recessive genes. Monoploids carry only a single set of chromosomes and every locus carries only one allele. So the surviving monoploids are devoid of lethal alleles due to the effect of the "monoploid sieve"
Protoplasts are plant cells, the cell walls of which have been digested by a combination of pectinase and cellulase enzymes. If the protoplasts are cultured in a suitable medium, they can resynthesize the cell walls, divide and regenerate complete plantlets. But if a successful fusion of protoplasts from sexually incompatible parents is achieved, the resulting somatic hybrid carries the genome contributed by both parents.
This study aims to apply the molecular tool of RAPD mapping as an efficient agent of plant (potato) genetic characterization of anther-derived monoploids and putative hybrids of a somatic fusion of two monoploids. / Master of Science
| Identifer | oai:union.ndltd.org:VTETD/oai:vtechworks.lib.vt.edu:10919/45455 |
| Date | 07 November 2008 |
| Creators | Ravichandran, Vidya |
| Contributors | Horticulture |
| Publisher | Virginia Tech |
| Source Sets | Virginia Tech Theses and Dissertation |
| Language | English |
| Detected Language | English |
| Type | Thesis, Text |
| Format | ix, 77 leaves, BTD, application/pdf, application/pdf |
| Rights | In Copyright, http://rightsstatements.org/vocab/InC/1.0/ |
| Relation | OCLC# 34937007, LD5655.V855_1996.R385.pdf |
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