著者

KATO Hajime YAMAMOTO Masaaki YAMAGUCHI-OZAKI Tomona KADOUCHI Hiroyuki IWAMOTO Yutaka NAKAYASHIKI Hitoshi TOSA Yukio MAYAMA Shigeyuki MORI Naoki

出版者

日本植物病理学会

雑誌

Journal of general plant pathology : JGPP (ISSN:13452630)

巻号頁・発行日

vol.66, no.1, pp.30-47, 2000-02-25

被引用文献数

14

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Eighty-five Pyricularia isolates were collected from 29 host species of Gramineae, Bambusideae and Zingiberaceae plants sampled in Brazil, Uganda, Ivory Coast, India, Nepal, China, Indonesia and Japan.These isolates were compared on the basis of pathogenicity, mating ability and restriction fragment length polymorphisms with single-copy DNA probes.Based on the pathogenicity to eight differential gramineous plants, these isolates were classified into seven pathotypes:finger millet type, foxtail millet type, common millet type, rice type, crabgrass type, Italian ryegrass / weeping lovegrass type, and non-cereal / grass type.Genetic variation among these isolates was assessed by RFLP analysis with two restriction enzymes and nine single-copy DNA probes isolated from a finger millet strain.An UPGMA dendrogram based on the RFLPs revealed that the 85 isolates could be classified into seven major groups.Isolates from cereal crops(finger millet, foxtail millet, common millet, wheat and rice)and a grass, Brachiaria plantaginea, were clustered into a single group.They were further divided into six subgroups corresponding to the pathotypes.Among cereal crop isolates only an isolate from pearl millet was located into a different group.The remaining isolates were clustered into five groups designated as the crabgrass group, the buffelgrass and jungle rice group, the rice cutgrass, knotroot bristlegrass and Setaria tomentosa group, the bamboo and bamboo grass group and the Zingiber mioga group.The isolates from cereal crops were generally capable of mating with finger millet strains and constituted a closed mating compatibility group.These results suggested that the isolates from cereal crops from a single group with a common ancestor although they are pathogenic to taxonomically diverse plants.A combined analysis of the pathogenicity and genetic similarity suggested that the transmission of M.grisea isolates occurs in natural agroecosystems between finger millet and Eleusine africana, goosegrass or Bambusa arundinacea, between foxtail millet and green bristlegrass, and between rice and tail fescue, Italian ryegrass, sweet vernalgrass, reed canarygrass or Oryza longistaminata.

著者

MAJUMDER Parimal SHIOIRI Hidenari NOZUE Masayuki KOJIMA Mineo

出版者

日本植物病理学会

雑誌

Journal of general plant pathology : JGPP (ISSN:13452630)

巻号頁・発行日

vol.67, no.2, pp.124-133, 2001-05-25

被引用文献数

4

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A mutant (M-1) was isolated by transposon (Tn5) insertion mutagenesis of Agrobacterium tumefaciens (strain A-208, C58 chromosome, nopaline type T37 pTi, virulent). The M-1 mutant exhibited a complete avirulent phenotype on Kalanchoe daigremontiana leaf and Kalanchoe pinnata stem but a very attenuated virulent phenotype on root of Daucus carota. The mutant had one insertion of Tn5 in pTi. A wild-type target segment (2.3 kb) that included the site of Tn5 insertion in M-1 mutant was cloned. Introducing the 2.3 kb segment into M-1 complemented completely the avirulent phenotype, producing galls as big as strain A-208. The 2.3 kb segment was sequenced, identifying three open reading frames, ORF 1 (354 bp), ORF 2 (261 bp) and ORF 3 (801 bp) in the segment. A Tn5 was inserted between the third and fourth nucleotide of ORF 1 in M-1. The ORF i had no homology to any reported genes and thus was named the abvA gene. The ORF 3 had the high homology (identities 44%, positive 68%) to the gene of the safcosine oxidase β subunit (accession no. sp/P40875). Introduction of the DNA segment (743 bp) containing the abvA gene and its promoter region into M-1 partially complemented the avirulent phenotype of the mutant, producing galls smaller than strain A-208. The abvA gene was distributed not only on nopaline-type pTi (T37) but also on octopine-type pTi (A6NC) and chromosome (C58) of A. tume」aciens. M-1, being avirulent on K. daigremontiana and K. pinnata, had a Tn5 insertion only in the abvA gene on pTi but not in the abvA gene on the chromosome, implying that the abvA gene on the chromosome in strain A-208 is not functional. A binary vector, pIG121-Hm, containing the β-glucuronidase (GUS) gene with an intron was introduced into M-1, which was then applied to leaves of K. daigremontiana to assay GUS activity for monitoring T-DNA transfer to the host nucleus. High GUS activity comparable to that in strain A-208 was detected in M-1 in spite of its inability to induce galls, suggesting that M-1 can transfer T-DNA into the host nucleus, but cannot integrate it into the chromosome. (Received October 25, 2000 ; Accepted December 28, 2000)