Mating-type loci segregate aberrantly in Phytophthora infestans but normally in Phytophthora parasitica: implications for models of mating-type determination.
In the oomycete, Phytophthora infestans, mating type is determined by a locus that segregates in a non-Mendelian manner consistent with its linkage to a system of balanced lethals. The significance of this unusual phenomenon was addressed by studying the segregation patterns of DNA markers linked to mating type in the related species, P. parasitica. This was done using loci identified by either RAPD analysis of P. parasitica crosses or by cross-hybridization with RFLP markers linked to mating type in P. infestans. The resulting data revealed that, unlike P. infestans, mating type in P. parasitica was regulated by a locus displaying Mendelian segregation. An improved model for mating-type determination in Phytophthora is presented.
Fabritius
A L
AL
Department of Plant Pathology, University of California, Riverside 92521, USA.
Judelson
H S
HS
D002874:Chromosome Mapping; D003433:Crosses, Genetic; D004271:DNA, Fungal / Q000235:genetics*; D005819:Genetic Markers; D010838:Phytophthora / Q000235:genetics / Q000502:physiology*; D012150:Polymorphism, Restriction Fragment Length; D019105:Random Amplified Polymorphic DNA Technique; D012098:Reproduction / Q000235:genetics
D004271:DNA, Fungal; D005819:Genetic Markers