The Effect of Cultural Conditions on Molecular Variation in Phytophthora infestans. Baines, L.C.D. and J.M. Bradeen
Phytophthora
Molecular Genetics
Observations that the long–term in vitro storage of Phytophthora infestans causes a reduction in pathogenicity
have been made over many years. It is not understood if this is a physiological
or genetic change. It is the aim of this
study to use molecular techniques now available to identify DNA mutations
brought about by post-collection storage. Isolates of P. infestans representing clonal
lineages US-1, US-6, US-7, US-8 and US-11 have been selected and amplified fragment-length
polymorphism fingerprints (AFLP) will be determined. Isolates will then be
maintained under various cultural conditions representative of normal storage
and experimentation, as well as conditions to induce changes in AFLP profiles. The
cultural conditions will include both in
vitro and in planta
storage using a variety of media and potato genotypes. Several AFLP pairs will
be examined and more than 300 markers are expected, providing broad
genome-coverage and enhancing the likelihood of detecting polymorphisms. This is a long-term study that will evaluate AFLP
as a marker system to complement other neutral-marker systems and phenotypic
markers currently used in population studies. Additionally, we will determine the
number of AFLP markers required to provide refined representation of natural P. infestans populations. To this end, we
welcome contribution of naturally-occurring P.
infestans samples collected within the