Introduction
There are many molecular techniques that are now available to assist plant breeders in
producing disease resistant crops. These resistant crops would negate the need for the use of
chemicals and other expensive disease preventative methods. Many pathogens have become
problems world wide due to the efficiency and speed of modern day travel, such as airplanes.
Tomatoes are one such crop that has been ravaged world wide by a large variety of pathogens,
such as Fusarium oxysporum f. sp. lycopersici. Among tomatoes there are wild species that have
genes that confer resistance to many of the problematic diseases, but their fruits are not
marketable. To assist plant breeders, techniques such as PCR (Polymerase Chain Reaction) are
being used to identify and track specific disease resistance genes through generations of breeding
lines. This allows for a more rapid production of disease resistant progeny at any locus of
interest by allowing plant breeders to select only the resistant progeny for the next generation of
breeding. This thesis discusses the uses of PCR and PCR primers that will enable researchers to
follow disease resistance genes at a multiple loci, allowing for the rapid identification of a plants
resistance or susceptibility to a pathogen.
This research was completed in the Department of Plant Pathology under the supervision
of Professor Emeritus Douglas P. Maxwell. It was supported by grants from CDR/USAID and
MERC/USAID to D. P. Maxwell.