GRADUATE STUDIES BULLETIN
ANNOUNCEMENT
Doctoral Proposal Seminar
Developing Useful Molecular Genetic Markers in
Tropical Trees
by
Useful molecular genetic markers are length or sequence
DNA polymorphisms. Molecular genetic
markers are utilized in breeding programs of numerous crops for selecting
desirable agronomic traits. This is known
either as marker assisted breeding or marker assisted selection. Markers cosegregating with the phenotype of
interest can be used for screening material for breeding.
Theobroma
cacao L. is the sole source of
cocoa, the raw material for producing chocolate. It is also one of the most economically important crops in the
tropics. Currently, there is an
international effort in improving disease resistance in T. cacao L.
through a marker assisted breeding program.
This project proposes to develop molecular genetic markers in T.
cacao L. using a candidate gene approach.
The
candidate gene approach identifies genes potentially involved in the expression
of a phenotype and assesses whether they can serve as useful markers for this
phenotype. This project will focus upon
WRKY transcriptional factors associated with the regulation of development and
defense responses in plants. Degenerate
PCR primers have been designed from conserved regions of WRKY genes and used
successfully to amplify 16 different target sequences. Ten of these sequences have been evaluated
within an F2 population segregating for resistance to Witches’ Broom
Disease caused by Crinipellis perniciosa. Three are polymorphic when assayed by Single Strand
Conformational Polymorphism (SSCP) capillary electrophoresis. Further research will be to assess the
remaining six isolated sequences for their utility as molecular markers within
the F2 population and assess the utility of all isolated sequences
among other F1 populations of T. cacao.
Date: February 7, 2002 Department: Biology
Time: 3:30 pm Major Professor: Dr. David N. Kuhn
Place: University Park, Wertheim Conservatory