RESTRICTION-FRAGMENT-LENGTH-POLYMORPHISMS IN COLLETOTRICHUM-GLOEOSPORIOIDES INFECTING STYLOSANTHES-SPP IN AUSTRALIA

Restriction fragment length polymorphisms (RFLPs) have been used to estimate the relationship between four isolates of each of the Type A and B forms of Colletotrichum gloeosporioides which cause anthracnose on Stylosanthes spp. They were distinguished by polymorphisms in ribosomal DNA repeats and after hybridization with both low and high copy random genomic probes. The nucleotide sequence divergence estimate confirmed the existence of two distinct pathogen populations in Australia. Two high copy probes indicated that genetic diversity was low within the Type B population. One diagnostic high copy probe could be used to distinguish a teleomorphic isolate and isolates from the tropical legumes Centrosema pubescens and Aeschynomene falcata, from the Type A and B isolates. RFLPs are, therefore, extremely useful for determining genetic relationships within C. gloeosporioides.