Gastrodia elata was collected from July to August 1992 in Hokkaido forests. A total of 22 diploid isolates were paired with haploid testers of the biological Armillaria species reported in Hokkaido. One isolate was identified as A. ostoyae, 10 as /I. gallica, three as A. jezoensis, three as A. sinapina, and five as A. singula. These isolates were compatible with the respective Hokkaido testers of these species. With the exception of A. ostoyae, these species are known as saprophytes, which form abundant rhizomorphs in soil.Clear isozyme profiles of esterases were obtained with all isolates except one. Interspecific variations were more important than intraspeeifie variations. The esterase profiles could be used for identification of the Armillaria species in Hokk.^ido as a useful complement to the mating-type method.U. S.

To determine the phylogenetie positions of two new speeies, Armillaria jezoensis and Armillaria singula, and one new subspecies, Armillaria mellea suhsp. nipponica, the nueleotide sequetices ot the intergenic spacers (IGS) ot their ribosomal DNA were investigated, and compared with those of tour other Armillaria species trom Japan, and those of nine Armillaria speeies from Europe and North Ameriea. We conclude that Armillaria jezoensis, and Armillaria singula belong to the Armillaria galliea cluster :is Armillaria cepistipes, Armillaria gaUica An<\ Armitlaria sinapina i\-om]i\p.\n.'Xwo\so\s.x.c^ oi Armillaria ostoyae front Japan were placed witliin the Armillaria ostoyae duster. Armillaria mellea stibsp. nipponiea had an IGS sequence as long as the IGS ot Armillaria mellea trom Europe and North Ameriea. However, the IGS sequences oi Armillaria mellea subsp. nipponiea, whose basidium base laeks a elamp conneetion eould not be satisfaetorily aligned with the IGS sequenees of other speeies possessing this morphological teature.