Phylogenetic analysis of nucleotide data from small subunit ribosomal DNA (SSU rDNA) sequences (ca. 1685 bp.) was performed on 19 taxa of the Onygenales and three related mitosporic fungi. Phylogenetic trees were constructed by the neighbor-joining method with the sequence data of related taxa obtained from DNA databases. The species in the Onygenales form two clusters and seven subclusters, and the tree topology reflects the traditional classification by Currah (1985) with some exceptions. The Myxotrichaceae is placed in the different lineage, separate from other plectomycetous taxa and among the Leotiales and the Erysiphales. Furthermore, two separate lineages in the Myxotrichaceae were found. Tree topology suggested the Onygenaceae is polyphyletic and composed of three subgroups; 1) most members of Onygenaceae, 2) Spiromastix warcupii, and 3) pathogenic dimorphic fungi classified in Ajellomyces. Key WordsOnygenales; phylogeny; small subunit rDNA.The Onygenales is an order of Ascomycota that produces gymnothecial or cleistothecial ascomata. In "Dictionary of the Fungi" (Hawksworth et al., 1995), 90 species of 36 genera are included in the order. The diagnostic characteristics of the family are as follows: 1 ) peridia are various in morphology, such as undifferentiated hyphae surrounding asci loosely or tightly, peridia with meshlike, disarticulating wall, and membranous wall or cleistothecia formed in stipitate stroma; 2) asci are spherical, thin-walled, deliquescent, and formed freely on the mycelium or within peridia; 3) ascospores are small, single-celled and hyaline or pale in color with various surface ornamentations; 4) anamorph is aleurio-or arthroconidia that seceding rhexolytically; 5) several taxa degrade keratin and are associated with animals or their products including dung, feathers and bones. In classifying of the Onygenales, ascoma structure was traditionally emphasized to circumscribe the taxa (Benjamin, 1956;Kuehn, 1958Kuehn, , 1959Apinis, 1964;Benny and Kimbrough, 1980). Currah (1985) revised this order based on a large number of collections and pointed out that the resemblance of peridial structure does not reflect the phylogenetic lineage because many of them might result from convergent evolution. He introduced physiological characteristics in addition to morphological differences of ascospore and conidia for the higher classification in the Onygenales, and established four families in this order, viz., Arthrodermataceae, Gymnoascaceae, Myxotrichaceae, and Onygenaceae. His system has been widely accepted among mycologists, though von Arx (1987) proposed another system based mainly on the morphology of ascospores. Yon Arx placed the onygenalean taxa into the Eurotiales, dividing the order among four families, i.e., the Amauroascaceae, Eurotiaceae, Gymnoascaceae and Onygenaceae.After Currah's monograph, new taxa or new combinations have been proposed, and physiological, ecological and molecular data related to the order have been accumulated. Based on new information about the order, reconsi...

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Hairy roots were induced from leaf segments of Crotalaria spectabilis, which is used as a green manure crop antagonistic to nematodes, by infection with a mikimopine type wild strain of Agrobacterium rhizogenes A13 (MAFF02-10266). For initial proliferation of hairy roots after induction, addition of gibberellin A 3 to the medium was indispensable. These roots exhibited vigorous growth and abundant lateral branching on half-strength Murashige and Skoog (1/2MS) medium without plant growth regulators. The adventitious shoots were induced from 24% of root segments 2 months after transfer onto B5 medium containing 5 mg l −1 6-benzyladenine. The axillary buds excised from these shoots produced roots 1 month after transfer onto 0.4% (wv −1 ) gellan gum-solidified 1/2MS medium containing 30 mM fructose without plant growth regulators. Regenerated plants were successfully grown under greenhouse conditions. Infection of hairy roots of C. spectabilis with root-knot nematodes Meloidogyne hapla and M. incognita led to the growth inhibition of these nematodes.

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